Sample records for background malaria control
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Health, human rights, and malaria control: historical background and current challenges.
Brentlinger, Paula E
2006-01-01
Malaria, a parasitic infection, causes hundreds of millions of disease episodes and more than a million deaths every year, nearly all of them occurring in the poorer and more vulnerable sectors of the world's developing countries. In spite of the great burden of suffering caused by malaria, the human rights implications of this disease have not been well described. This article summarizes important associations between the spread of malaria and human rights abuses (such as those associated with slavery and armed conflict) and between poverty, socio-economic inequity, and access to malaria-control measures. The author concludes that malaria control merits inclusion as a core element in global strategies to achieve progressive realization of the right to health.
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Progress towards malaria control targets in relation to national malaria programme funding
2013-01-01
Background Malaria control has been dramatically scaled up the past decade, mainly thanks to increasing international donor financing since 2003. This study assessed progress up to 2010 towards global malaria impact targets, in relation to Global Fund, other donor and domestic malaria programme financing over 2003 to 2009. Methods Assessments used domestic malaria financing reported by national programmes, and Global Fund/OECD data on donor financing for 90 endemic low- and middle-income countries, WHO estimates of households owning one or more insecticide-treated mosquito net (ITN) for countries in sub-Saharan Africa, and WHO-estimated malaria case incidence and deaths in countries outside sub-Saharan Africa. Results Global Fund and other donor funding is concentrated in a subset of the highest endemic African countries. Outside Africa, donor funding is concentrated in those countries with highest malaria mortality and case incidence rates over the years 2000 to 2003. ITN coverage in 2010 in Africa, and declines in case and death rates per person at risk over 2004 to 2010 outside Africa, were greatest in countries with highest donor funding per person at risk, and smallest in countries with lowest donor malaria funding per person at risk. Outside Africa, all-source malaria programme funding over 2003 to 2009 per case averted ($56-5,749) or per death averted ($58,000-3,900,000) over 2004 to 2010 tended to be lower (more favourable) in countries with higher donor malaria funding per person at risk. Conclusions Increases in malaria programme funding are associated with accelerated progress towards malaria control targets. Associations between programme funding per person at risk and ITN coverage increases and declines in case and death rates suggest opportunities to maximize the impact of donor funding, by strategic re-allocation to countries with highest continued need. PMID:23317000
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Strengthening the policy setting process for global malaria control and elimination.
D'Souza, Bianca J; Newman, Robert D
2012-01-27
The scale-up of malaria control efforts in recent years, coupled with major investments in malaria research, has produced impressive public health impact in a number of countries and has led to the development of new tools and strategies aimed at further consolidating malaria control goals. As a result, there is a growing need for the malaria policy setting process to rapidly review increasing amounts of evidence. The World Health Organization Global Malaria Programme, in keeping with its mandate to set evidence-informed policies for malaria control, has convened the Malaria Policy Advisory Committee as a mechanism to increase the timeliness, transparency, independence and relevance of its recommendations to World Health Organization member states in relation to malaria control and elimination. The Malaria Policy Advisory Committee, composed of 15 world-renowned malaria experts, will meet in full twice a year, with the inaugural meeting scheduled for 31 January to 2 February 2012 in Geneva. Policy recommendations, and the evidence to support them, will be published within two months of every meeting as part of an open access Malaria Journal thematic series. This article is a prelude to that series and provides the global malaria community with the background and overview of the Committee and its terms of reference.
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Malaria control: achievements, problems and strategies.
Nájera, J A
2001-06-01
Even if history has not always been the Magistra vitae, Cicero expected it to be, it should provide, as Baas said, a mirror in which to observe and compare the past and present in order to draw therefrom well-grounded conclusions for the future. Based on this belief, this paper aims to provide an overview of the foundations and development of malaria control policies during the XX century. It presents an analysis of the conflicting tendencies which shaped the development of these policies and which appear to have oscillated between calls for frontal attack in an all-out campaign and calls for sustainable gains, even if slow. It discusses the various approaches to the control of malaria, their achievements and their limitations, not only to serve as a background to understand better the foundations of current policies, but also to prevent that simplistic generalisations may again lead to exaggerated expectations and disillusion. The first part of the paper is devoted to the development of malaria control during the first half of the century, characterised by the ups and downs in the reliance on mosquito control as the control measure applicable everywhere. The proliferation of "man-made-malaria", which accompanied the push for economic development in most of the endemic countries, spurred the need for control interventions and, while great successes were obtained in many specific projects, the general campaigns proposed by the enthusiasts of vector control faced increasing difficulties in their practical implementation in the field. Important events, which may be considered representative of this period are, on the campaign approach, the success of Gorgas in the Panama Canal, but also the failure of the Mian Mir project in India; while on the developmental approach, the Italian and Dutch schools of malariology, the Tennessee Valley and the development of malaria sanitation, included the so called species sanitation. The projection of these developments to a global
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Application of loop analysis for evaluation of malaria control interventions
2014-01-01
Background Despite continuous efforts and recent rapid expansion in the financing and implementation of malaria control interventions, malaria still remains one of the most devastating global health issues. Even in countries that have been successful in reducing the incidence of malaria, malaria control is becoming more challenging because of the changing epidemiology of malaria and waning community participation in control interventions. In order to improve the effectiveness of interventions and to promote community understanding of the necessity of continued control efforts, there is an urgent need to develop new methodologies that examine the mechanisms by which community-based malaria interventions could reduce local malaria incidence. Methods This study demonstrated how the impact of community-based malaria control interventions on malaria incidence can be examined in complex systems by qualitative analysis combined with an extensive review of literature. First, sign digraphs were developed through loop analysis to analyse seven interventions: source reduction, insecticide/larvicide use, biological control, treatment with anti-malarials, insecticide-treated mosquito net/long-lasting insecticidal net, non-chemical personal protection measures, and educational intervention. Then, for each intervention, the sign digraphs and literature review were combined to analyse a variety of pathways through which the intervention can influence local malaria incidence as well as interactions between variables involved in the system. Through loop analysis it is possible to see whether increases in one variable qualitatively increases or decreases other variables or leaves them unchanged and the net effect of multiple, interacting variables. Results Qualitative analysis, specifically loop analysis, can be a useful tool to examine the impact of community-based malaria control interventions. Without relying on numerical data, the analysis was able to describe pathways through
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[Global trends in malaria control. Progress and topical tasks in malaria control programs].
Kondrashin, A V; Baranova, A M; Morozova, L F; Stepanova, E V
2011-01-01
This communication is the first in the series consisting of two publications describing the present state of malaria control and elimination in the world. The global malaria situation in 2009-2010 demonstrated a considerable situation as compared to the previous years. This improvement is associated with a considerable global increase of investments made by both national governments and world society to the malaria control programs. Spectacular progress has been achieved even in the areas of the most infection-affected African countries situated to the south of the Sahara Desert. It has been estimated that malaria cases in the world declined from 233, 000,000 in 2000 to 225,000,000 in 2009. Malaria mortality decreased from 985,000 in 2000 to 781,000 in 2009. To maintain the results achieved and to further reduce the problem of malaria worldwide, it is necessary to ensure a long-term political and financial support for malaria control programs at the national and international levels.
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Funding for malaria control 2006–2010: A comprehensive global assessment
2012-01-01
Background The last decade has seen a dramatic increase in international and domestic funding for malaria control, coupled with important declines in malaria incidence and mortality in some regions of the world. As the ongoing climate of financial uncertainty places strains on investment in global health, there is an increasing need to audit the origin, recipients and geographical distribution of funding for malaria control relative to populations at risk of the disease. Methods A comprehensive review of malaria control funding from international donors, bilateral sources and national governments was undertaken to reconstruct total funding by country for each year 2006 to 2010. Regions at risk from Plasmodium falciparum and/or Plasmodium vivax transmission were identified using global risk maps for 2010 and funding was assessed relative to populations at risk. Those nations with unequal funding relative to a regional average were identified and potential explanations highlighted, such as differences in national policies, government inaction or donor neglect. Results US$8.9 billion was disbursed for malaria control and elimination programmes over the study period. Africa had the largest levels of funding per capita-at-risk, with most nations supported primarily by international aid. Countries of the Americas, in contrast, were supported typically through national government funding. Disbursements and government funding in Asia were far lower with a large variation in funding patterns. Nations with relatively high and low levels of funding are discussed. Conclusions Global funding for malaria control is substantially less than required. Inequity in funding is pronounced in some regions particularly when considering the distinct goals of malaria control and malaria elimination. Efforts to sustain and increase international investment in malaria control should be informed by evidence-based assessment of funding equity. PMID:22839432
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Integrated vector management for malaria control
Beier, John C; Keating, Joseph; Githure, John I; Macdonald, Michael B; Impoinvil, Daniel E; Novak, Robert J
2008-01-01
Integrated vector management (IVM) is defined as "a rational decision-making process for the optimal use of resources for vector control" and includes five key elements: 1) evidence-based decision-making, 2) integrated approaches 3), collaboration within the health sector and with other sectors, 4) advocacy, social mobilization, and legislation, and 5) capacity-building. In 2004, the WHO adopted IVM globally for the control of all vector-borne diseases. Important recent progress has been made in developing and promoting IVM for national malaria control programmes in Africa at a time when successful malaria control programmes are scaling-up with insecticide-treated nets (ITN) and/or indoor residual spraying (IRS) coverage. While interventions using only ITNs and/or IRS successfully reduce transmission intensity and the burden of malaria in many situations, it is not clear if these interventions alone will achieve those critical low levels that result in malaria elimination. Despite the successful employment of comprehensive integrated malaria control programmes, further strengthening of vector control components through IVM is relevant, especially during the "end-game" where control is successful and further efforts are required to go from low transmission situations to sustained local and country-wide malaria elimination. To meet this need and to ensure sustainability of control efforts, malaria control programmes should strengthen their capacity to use data for decision-making with respect to evaluation of current vector control programmes, employment of additional vector control tools in conjunction with ITN/IRS tactics, case-detection and treatment strategies, and determine how much and what types of vector control and interdisciplinary input are required to achieve malaria elimination. Similarly, on a global scale, there is a need for continued research to identify and evaluate new tools for vector control that can be integrated with existing biomedical
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Malaria control in South Sudan, 2006–2013: strategies, progress and challenges
2013-01-01
Background South Sudan has borne the brunt of years of chronic warfare and probably has the highest malaria burden in sub-Saharan Africa. However, effective malaria control in post-conflict settings is hampered by a multiplicity of challenges. This manuscript reports on the strategies, progress and challenges of malaria control in South Sudan and serves as an example epitome for programmes operating in similar environments and provides a window for leveraging resources. Case description To evaluate progress and challenges of the national malaria control programme an in-depth appraisal was undertaken according to the World Health Organization standard procedures for malaria programme performance review. Methodical analysis of published and unpublished documents on malaria control in South Sudan was conducted. To ensure completeness, findings of internal thematic desk assessments were triangulated in the field and updated by external review teams. Discussion and evaluation South Sudan has strived to make progress in implementing the WHO recommended malaria control interventions as set out in the 2006–2013 National Malaria Strategic Plan. The country has faced enormous programmatic constraints including infrastructure, human and financial resource and a weak health system compounded by an increasing number of refugees, returnees and internally displaced people. The findings present a platform on which to tailor an evidence-based 2014–2018 national malaria strategic plan for the country and a unique opportunity for providing a model for countries in a post-conflict situation. Conclusions The prospects for effective malaria control and elimination are huge in South Sudan. Nevertheless, strengthened coordination, infrastructure and human resource capacity, monitoring and evaluation are required. To achieve all this, allocation of adequate local funding would be critical. PMID:24160336
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How well are malaria maps used to design and finance malaria control in Africa?
Omumbo, Judy A; Noor, Abdisalan M; Fall, Ibrahima S; Snow, Robert W
2013-01-01
Rational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed. An audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated. 91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control. The way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be necessary to guide appropriate financing for malaria
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Ranking malaria risk factors to guide malaria control efforts in African highlands.
Protopopoff, Natacha; Van Bortel, Wim; Speybroeck, Niko; Van Geertruyden, Jean-Pierre; Baza, Dismas; D'Alessandro, Umberto; Coosemans, Marc
2009-11-25
Malaria is re-emerging in most of the African highlands exposing the non immune population to deadly epidemics. A better understanding of the factors impacting transmission in the highlands is crucial to improve well targeted malaria control strategies. A conceptual model of potential malaria risk factors in the highlands was built based on the available literature. Furthermore, the relative importance of these factors on malaria can be estimated through "classification and regression trees", an unexploited statistical method in the malaria field. This CART method was used to analyse the malaria risk factors in the Burundi highlands. The results showed that Anopheles density was the best predictor for high malaria prevalence. Then lower rainfall, no vector control, higher minimum temperature and houses near breeding sites were associated by order of importance to higher Anopheles density. In Burundi highlands monitoring Anopheles densities when rainfall is low may be able to predict epidemics. The conceptual model combined with the CART analysis is a decision support tool that could provide an important contribution toward the prevention and control of malaria by identifying major risk factors.
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Ethical aspects of malaria control and research.
Jamrozik, Euzebiusz; de la Fuente-Núñez, Vânia; Reis, Andreas; Ringwald, Pascal; Selgelid, Michael J
2015-12-22
Malaria currently causes more harm to human beings than any other parasitic disease, and disproportionally affects low-income populations. The ethical issues raised by efforts to control or eliminate malaria have received little explicit analysis, in comparison with other major diseases of poverty. While some ethical issues associated with malaria are similar to those that have been the subject of debate in the context of other infectious diseases, malaria also raises distinct ethical issues in virtue of its unique history, epidemiology, and biology. This paper provides preliminary ethical analyses of the especially salient issues of: (i) global health justice, (ii) universal access to malaria control initiatives, (iii) multidrug resistance, including artemisinin-based combination therapy (ACT) resistance, (iv) mandatory screening, (v) mass drug administration, (vi) benefits and risks of primaquine, and (vii) malaria in the context of blood donation and transfusion. Several ethical issues are also raised by past, present and future malaria research initiatives, in particular: (i) controlled infection studies, (ii) human landing catches, (iii) transmission-blocking vaccines, and (iv) genetically-modified mosquitoes. This article maps the terrain of these major ethical issues surrounding malaria control and elimination. Its objective is to motivate further research and discussion of ethical issues associated with malaria--and to assist health workers, researchers, and policy makers in pursuit of ethically sound malaria control practice and policy.
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Optimal control for Malaria disease through vaccination
NASA Astrophysics Data System (ADS)
Munzir, Said; Nasir, Muhammad; Ramli, Marwan
2018-01-01
Malaria is a disease caused by an amoeba (single-celled animal) type of plasmodium where anopheles mosquito serves as the carrier. This study examines the optimal control problem of malaria disease spread based on Aron and May (1982) SIR type models and seeks the optimal solution by minimizing the prevention of the spreading of malaria by vaccine. The aim is to investigate optimal control strategies on preventing the spread of malaria by vaccination. The problem in this research is solved using analytical approach. The analytical method uses the Pontryagin Minimum Principle with the symbolic help of MATLAB software to obtain optimal control result and to analyse the spread of malaria with vaccination control.
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Sustainable malaria control: transdisciplinary approaches for translational applications
2012-01-01
With the adoption of the Global Malaria Action Plan, several countries are moving from malaria control towards elimination and eradication. However, the sustainability of some of the approaches taken may be questionable. Here, an overview of malaria control and elimination strategies is provided and the sustainability of each in context of vector- and parasite control is assessed. From this, it can be concluded that transdisciplinary approaches are essential for sustained malaria control and elimination in malaria-endemic communities. PMID:23268712
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A historical perspective on malaria control in Brazil
Griffing, Sean Michael; Tauil, Pedro Luiz; Udhayakumar, Venkatachalam; Silva-Flannery, Luciana
2015-01-01
Malaria has always been an important public health problem in Brazil. The early history of Brazilian malaria and its control was powered by colonisation by Europeans and the forced relocation of Africans as slaves. Internal migration brought malaria to many regions in Brazil where, given suitableAnopheles mosquito vectors, it thrived. Almost from the start, officials recognised the problem malaria presented to economic development, but early control efforts were hampered by still developing public health control and ignorance of the underlying biology and ecology of malaria. Multiple regional and national malaria control efforts have been attempted with varying success. At present, the Amazon Basin accounts for 99% of Brazil’s reported malaria cases with regional increases in incidence often associated with large scale public works or migration. Here, we provide an exhaustive summary of primary literature in English, Spanish and Portuguese regarding Brazilian malaria control. Our goal was not to interpret the history of Brazilian malaria control from a particular political or theoretical perspective, but rather to provide a straightforward, chronological narrative of the events that have transpired in Brazil over the past 200 years and identify common themes. PMID:26517649
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William, Timothy; Rahman, Hasan A.; Jelip, Jenarun; Ibrahim, Mohammad Y.; Menon, Jayaram; Grigg, Matthew J.; Yeo, Tsin W.; Anstey, Nicholas M.; Barber, Bridget E.
2013-01-01
Background The simian parasite Plasmodium knowlesi is a common cause of human malaria in Malaysian Borneo and threatens the prospect of malaria elimination. However, little is known about the emergence of P. knowlesi, particularly in Sabah. We reviewed Sabah Department of Health records to investigate the trend of each malaria species over time. Methods Reporting of microscopy-diagnosed malaria cases in Sabah is mandatory. We reviewed all available Department of Health malaria notification records from 1992–2011. Notifications of P. malariae and P. knowlesi were considered as a single group due to microscopic near-identity. Results From 1992–2011 total malaria notifications decreased dramatically, with P. falciparum peaking at 33,153 in 1994 and decreasing 55-fold to 605 in 2011, and P. vivax peaking at 15,857 in 1995 and decreasing 25-fold to 628 in 2011. Notifications of P. malariae/P. knowlesi also demonstrated a peak in the mid-1990s (614 in 1994) before decreasing to ≈100/year in the late 1990s/early 2000s. However, P. malariae/P. knowlesi notifications increased >10-fold between 2004 (n = 59) and 2011 (n = 703). In 1992 P. falciparum, P. vivax and P. malariae/P. knowlesi monoinfections accounted for 70%, 24% and 1% respectively of malaria notifications, compared to 30%, 31% and 35% in 2011. The increase in P. malariae/P. knowlesi notifications occurred state-wide, appearing to have begun in the southwest and progressed north-easterly. Conclusions A significant recent increase has occurred in P. knowlesi notifications following reduced transmission of the human Plasmodium species, and this trend threatens malaria elimination. Determination of transmission dynamics and risk factors for knowlesi malaria is required to guide measures to control this rising incidence. PMID:23359830
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2010-01-01
Background Despite Vietnam's success in reducing malaria mortality and morbidity over the last decade, malaria persists in the forested and mountainous areas of the central and southern provinces, where more than 50% of the clinical cases and 90% of severe cases and malaria deaths occur. Methods Between July 2005 and September 2006, a multi-method study, triangulating a malariometric cross-sectional survey and qualitative data from focused ethnography, was carried out among the Ra-glai ethnic minority in the hilly forested areas of south-central Vietnam. Results Despite the relatively high malaria burden among the Ra-glai and their general awareness that mosquitoes can transmit an unspecific kind of fever (84.2%), the use of bed nets, distributed free of charge by the national malaria control programme, remains low at the farmers' forest fields where the malaria risk is the highest. However, to meet work requirements during the labour intensive malaria transmission and rainy season, Ra-glai farmers combine living in government supported villages along the road with a second home or shelter at their slash and burn fields located in the forest. Bed net use was 84.6% in the villages but only 52.9% at the forest fields; 20.6% of the respondents slept unprotected in both places. Such low use may be explained by the low perception of the risk for malaria, decreasing the perceived need to sleep protected. Several reasons may account for this: (1) only 15.6% acknowledged the higher risk of contracting malaria in the forest than in the village; (2) perceived mosquito biting times only partially coincided with Anopheles dirus ss and Anopheles minimus A true biting times; (3) the disease locally identified as 'malaria' was hardly perceived as having an impact on forest farmers' daily lives as they were unaware of the specific kind of fevers from which they had suffered even after being diagnosed with malaria at the health centre (20.9%). Conclusions The progressive
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Changing strategy in malaria control
Pampana, E. J.
1954-01-01
Residual-insecticide spraying methods may lead to the eradication of malaria from a country or from an area of it, and therefore to the possibility that the spraying campaign may eventually be discontinued. This is the final target to be aimed at in planning national malaria-control campaigns. As it is now known that some anopheline vector species may develop resistance to insecticides, a plea is made that control programmes should be planned to cover such large areas and with such criteria of efficiency as to eradicate malaria and to enable the campaign to be discontinued before resistance may have developed. PMID:13209311
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From malaria control to eradication: The WHO perspective.
Mendis, Kamini; Rietveld, Aafje; Warsame, Marian; Bosman, Andrea; Greenwood, Brian; Wernsdorfer, Walther H
2009-07-01
Efforts to control malaria have been boosted in the past few years with increased international funding and greater political commitment. Consequently, the reported malaria burden is being reduced in a number of countries throughout the world, including in some countries in tropical Africa where the burden of malaria is greatest. These achievements have raised new hopes of eradicating malaria. This paper summarizes the outcomes of a World Health Organization's expert meeting on the feasibility of such a goal. Given the hindsight and experience of the Global Malaria Eradication Programme of the 1950s and 1960s, and current knowledge of the effectiveness of antimalarial tools and interventions, it would be feasible to effectively control malaria in all parts of the world and greatly reduce the enormous morbidity and mortality of malaria. It would also be entirely feasible to eliminate malaria from countries and regions where the intensity of transmission is low to moderate, and where health systems are strong. Elimination of malaria requires a re-orientation of control activity, moving away from a population-based coverage of interventions, to one based on a programme of effective surveillance and response. Sustained efforts will be required to prevent the resurgence of malaria from where it is eliminated. Eliminating malaria from countries where the intensity of transmission is high and stable such as in tropical Africa will require more potent tools and stronger health systems than are available today. When such countries have effectively reduced the burden of malaria, the achievements will need to be consolidated before a programme re-orientation towards malaria elimination is contemplated. Malaria control and elimination are under the constant threat of the parasite and vector mosquito developing resistance to medicines and insecticides, which are the cornerstones of current antimalarial interventions. The prospects of malaria eradication, therefore, rest heavily
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Mosquito larval source management for controlling malaria
Tusting, Lucy S; Thwing, Julie; Sinclair, David; Fillinger, Ulrike; Gimnig, John; Bonner, Kimberly E; Bottomley, Christian; Lindsay, Steven W
2015-01-01
Background Malaria is an important cause of illness and death in people living in many parts of the world, especially sub-Saharan Africa. Long-lasting insecticide treated bed nets (LLINs) and indoor residual spraying (IRS) reduce malaria transmission by targeting the adult mosquito vector and are key components of malaria control programmes. However, mosquito numbers may also be reduced by larval source management (LSM), which targets mosquito larvae as they mature in aquatic habitats. This is conducted by permanently or temporarily reducing the availability of larval habitats (habitat modification and habitat manipulation), or by adding substances to standing water that either kill or inhibit the development of larvae (larviciding). Objectives To evaluate the effectiveness of mosquito LSM for preventing malaria. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; CABS Abstracts; and LILACS up to 24 October 2012. We handsearched the Tropical Diseases Bulletin from 1900 to 2010, the archives of the World Health Organization (up to 11 February 2011), and the literature database of the Armed Forces Pest Management Board (up to 2 March 2011). We also contacted colleagues in the field for relevant articles. Selection criteria We included cluster randomized controlled trials (cluster-RCTs), controlled before-and-after trials with at least one year of baseline data, and randomized cross-over trials that compared LSM with no LSM for malaria control. We excluded trials that evaluated biological control of anopheline mosquitoes with larvivorous fish. Data collection and analysis At least two authors assessed each trial for eligibility. We extracted data and at least two authors independently determined the risk of bias in the included studies. We resolved all disagreements through discussion with a third author. We analyzed the data using Review Manager 5 software
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EMIRA: Ecologic Malaria Reduction for Africa--innovative tools for integrated malaria control.
Dambach, Peter; Traoré, Issouf; Becker, Norbert; Kaiser, Achim; Sié, Ali; Sauerborn, Rainer
2014-01-01
Malaria control is based on early treatment of cases and on vector control. The current measures for malaria vector control in Africa are mainly based on long-lasting insecticide treated nets (LLINs) and to a much smaller extent on indoor residual spraying (IRS). A third pillar in the fight against the malaria vector, larval source management (LSM), has virtually not been used in Africa since the ban of DDT in the 1960s. Within the light of recent WHO recommendations for Bacillus thuringiensis israelensis (Bti) use against malaria and other vector species, larval source management could see a revival in the upcoming years. In this project we analyze the ecologic and health impacts as well as the cost effectiveness of larval source management under different larviciding scenarios in a health district in Burkina Faso. The project is designed as prospective intervention study with duration of three years (2013-2015). Its spatial scale includes three arms of interventions and control, comprising a total of 127 villages and the district capital Nouna in the extended HDSS (Health Demographic Surveillance System) of the Kossi province. Baseline data on mosquito abundance, parasitemia in U5 children, and malaria related morbidity and mortality are gathered over the project duration. Besides the outcome on ecologic and health parameters, the economic costs are seized and valued against the achieved health benefits. Risk map based, guided larvicide application might be a possibility to further decrease economic cost of LSM and facilitate its faster incorporation to integrated malaria control programs. Given the limited resources in many malaria endemic countries, it is of utmost importance to relate the costs of novel strategies for malaria prevention to their effect on the burden of the disease. Occurring costs and the impact on the health situation will be made comparable to other, existing intervention strategies, allowing stakeholders and policymakers decision making.
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Revisiting the Basic Reproductive Number for Malaria and Its Implications for Malaria Control
Smith, David L; McKenzie, F. Ellis; Snow, Robert W; Hay, Simon I
2007-01-01
The prospects for the success of malaria control depend, in part, on the basic reproductive number for malaria, R 0. Here, we estimate R 0 in a novel way for 121 African populations, and thereby increase the number of R 0 estimates for malaria by an order of magnitude. The estimates range from around one to more than 3,000. We also consider malaria transmission and control in finite human populations, of size H. We show that classic formulas approximate the expected number of mosquitoes that could trace infection back to one mosquito after one parasite generation, Z 0(H), but they overestimate the expected number of infected humans per infected human, R 0(H). Heterogeneous biting increases R 0 and, as we show, Z 0(H), but we also show that it sometimes reduces R 0(H); those who are bitten most both infect many vectors and absorb infectious bites. The large range of R 0 estimates strongly supports the long-held notion that malaria control presents variable challenges across its transmission spectrum. In populations where R 0 is highest, malaria control will require multiple, integrated methods that target those who are bitten most. Therefore, strategic planning for malaria control should consider R 0, the spatial scale of transmission, human population density, and heterogeneous biting. PMID:17311470
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Re-imagining malaria--a platform for reflections to widen horizons in malaria control.
Hausmann-Muela, Susanna; Eckl, Julian
2015-04-24
Ongoing political-economic discussions that take stock of social and societal determinants of health present an opportunity for productive dialogue on why current approaches to malaria control and elimination need to be broadened, and how this may be accomplished. They invite us, for example, to look beyond malaria as a disease, to appreciate the experiences of malaria-afflicted populations, to transcend techno-centric approaches, to investigate social conflicts around malaria, to give voice to the communities engaged in bottom-up approaches, and to revisit lessons learned in the past. While contributions from all disciplines are invited to this discussion, social scientists are particularly encouraged to participate. They have struggled in the past to find an appropriate platform within the malaria community that provides them the opportunity to address researchers from other disciplines, malaria practitioners, and policy makers. The Malaria Journal's new thematic series on 're-imagining malaria' offers them this opportunity. The goal of the series is to encourage transdisciplinary thinking, to stimulate discussion, to promote constructive criticism, and to gather overlooked experiences that help to reflect on implicit assumptions. Overall it aims at widening horizons in malaria control.
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Radar Monitoring of Wetlands for Malaria Control
NASA Technical Reports Server (NTRS)
Pope, Kevin O.
1997-01-01
Malaria is perhaps the most serious human disease problem. It inflicts millions worldwide and is on the rise in many countries where it was once under control. This rise is in part due to the high costs, both economic and environmental, of current control programs. The search for more cost-effective means to combat malaria has focussed attention on new technologies, one of which is remote sensing. Remote sensing has become an important tool in the effort to control a variety of diseases worldwide and malaria is perhaps one of the most promising. This study is part of the malaria control effort in the Central American country of Belize, which has experienced a resurgence of malaria in the last two decades. The proposed project is a feasibility study of the use of Radarsat (and other similar radar systems) to monitor seasonal changes in the breeding sites of the anopheline mosquito, which is responsible for malaria transmission. We propose that spatial and temporal changes in anopheline mosquito production can be predicted by sensing where and when their breeding sites are flooded. Timely knowledge of anopheline mosquito production is a key factor in control efforts. Such knowledge can be used by local control agencies to direct their limited resources to selected areas and time periods when the human population is at greatest risk. Radar is a key sensor in this application because frequent cloud cover during the peak periods of malaria transmission precludes the use of optical sensors.
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Integrated Approach to Malaria Control
Shiff, Clive
2002-01-01
Malaria draws global attention in a cyclic manner, with interest and associated financing waxing and waning according to political and humanitarian concerns. Currently we are on an upswing, which should be carefully developed. Malaria parasites have been eliminated from Europe and North America through the use of residual insecticides and manipulation of environmental and ecological characteristics; however, in many tropical and some temperate areas the incidence of disease is increasing dramatically. Much of this increase results from a breakdown of effective control methods developed and implemented in the 1960s, but it has also occurred because of a lack of trained scientists and control specialists who live and work in the areas of endemic infection. Add to this the widespread resistance to the most effective antimalarial drug, chloroquine, developing resistance to other first-line drugs such as sulfadoxine-pyrimethamine, and resistance of certain vector species of mosquito to some of the previously effective insecticides and we have a crisis situation. Vaccine research has proceeded for over 30 years, but as yet there is no effective product, although research continues in many promising areas. A global strategy for malaria control has been accepted, but there are critics who suggest that the single strategy cannot confront the wide range of conditions in which malaria exists and that reliance on chemotherapy without proper control of drug usage and diagnosis will select for drug resistant parasites, thus exacerbating the problem. An integrated approach to control using vector control strategies based on the biology of the mosquito, the epidemiology of the parasite, and human behavior patterns is needed to prevent continued upsurge in malaria in the endemic areas. PMID:11932233
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Nonvignon, Justice; Aryeetey, Genevieve Cecilia; Malm, Keziah L; Agyemang, Samuel Agyei; Aubyn, Vivian N A; Peprah, Nana Yaw; Bart-Plange, Constance N; Aikins, Moses
2016-09-06
Despite the significant gains made globally in reducing the burden of malaria, the disease remains a major public health challenge, especially in sub-Saharan Africa (SSA) including Ghana. There is a significant gap in financing malaria control globally. The private sector could become a significant source of financing malaria control. To get the private sector to appreciate the need to invest in malaria control, it is important to provide evidence of the economic burden of malaria on businesses. The objective of this study, therefore, was to estimate the economic burden on malaria on businesses in Ghana, so as to stimulate the sector's investment in malaria control. Data covering 2012-2014 were collected from 62 businesses sampled from Greater Accra, Ashanti and Western Regions of Ghana, which have the highest concentration of businesses in the country. Data on the cost of businesses' spending on treatment and prevention of malaria in staff and their dependants as well as staff absenteeism due to malaria and expenditure on other health-related activities were collected. Views of business leaders on the effect of malaria on their businesses were also compiled. The analysis was extrapolated to cover 5828 businesses across the country. The results show that businesses in Ghana lost about US$6.58 million to malaria in 2014, 90 % of which were direct costs. A total of 3913 workdays were lost due to malaria in firms in the study sample during the period 2012-2014. Businesses in the study sample spent an average of 0.5 % of the annual corporate returns on treatment of malaria in employees and their dependants, 0.3 % on malaria prevention, and 0.5 % on other health-related corporate social responsibilities. Again business leaders affirmed that malaria affects their businesses' efficiency, employee attendance and productivity and expenses. Finally, about 93 % of business leaders expressed the need private sector investment in malaria control. The economic burden of
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Recht, Judith; Siqueira, André M; Monteiro, Wuelton M; Herrera, Sonia M; Herrera, Sócrates; Lacerda, Marcus V G
2017-07-04
In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.
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The use of a GIS-based malaria information system for malaria research and control in South Africa.
Martin, Carrin; Curtis, Bronwyn; Fraser, Colleen; Sharp, Brian
2002-12-01
The paper aims to outline the innovative development and application of a Geographical Information System based Malaria Information System for malaria research and control in South Africa. This system is a product of collaboration between the Malaria Control Programmes and the Malaria Research Programme of the Medical Research Council of South Africa. The ability of such a system to process data timeously into a usable format is discussed, as well as its relevance to malaria research, appropriate malaria control measures, tourism, and social and economic development.
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Assan, Abraham; Takian, Amirhossein; Hanafi-Bojd, Ahmad Ali; Rahimiforoushani, Abbas; Nematolahi, Shahrzad
2017-11-01
Despite continuing international attention to malaria prevention, the disease remains a global public health problem. We investigated socio-demographic factors influencing knowledge, attitudes, and practices about malaria in rural Ghana. Our survey looked at 354 households. Mean knowledge score was higher among individuals with a history of volunteers having visited their households to educate them about malaria; families with 4-6 members; and males. Households with at least one under-five-aged child also had significantly higher knowledge scores. Households with at least one pregnant woman evinced a positive attitude towards malaria prevention. National malaria control strategies have achieved positive results in the fight against malaria. Nonetheless, multipronged community-based health strategies that integrate malaria programs and population growth control initiatives may be able to reach by 2030 the sustainable development goal of eliminating malaria.
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Urbanization in sub-saharan Africa and implication for malaria control.
Keiser, Jennifer; Utzinger, Jurg; Caldas de Castro, Marcia; Smith, Thomas A; Tanner, Marcel; Singer, Burton H
2004-08-01
Malaria not only remains a leading cause of morbidity and mortality, but it also impedes socioeconomic development, particularly in sub-Saharan Africa. Rapid and unprecedented urbanization, going hand-in-hand with often declining economies, might have profound implications for the epidemiology and control of malaria, as the relative disease burden increases among urban dwellers. Reviewing the literature and using a modeling approach, we find that entomologic inoculation rates in cities range from 0 to 54 per year, depending on the degree of urbanization, the spatial location within a city, and overall living conditions. Using the latest United Nations figures on urbanization prospects, nighttime light remotely sensed images, and the "Mapping Malaria Risk in Africa" results on climate suitability for stable malaria transmission, we estimate that 200 million people (24.6% of the total African population) currently live in urban settings where they are at risk of contracting the disease. Importantly, the estimated total surface area covered by these urban settings is only approximately 1.1-1.6% of the total African surface. Considering different plausible scenarios, we estimate an annual incidence of 24.8-103.2 million cases of clinical malaria attacks among urban dwellers in Africa. These figures translate to 6-28% of the estimated global annual disease incidence. Against this background, basic health care delivery systems providing early diagnosis and early treatment and preventive actions through mother and child health programs and the promotion of insecticide-treated bed nets for the rapidly growing numbers of the urban poor must be improved alongside well-tailored and integrated malaria control strategies. We propose environmental management and larviciding within well-specified productive sites as a main feature for such an integrated control approach. Mitigation of the current burden of malaria in urban African settings, in turn, is a necessity for stimulating
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The Biological Control of the Malaria Vector
Kamareddine, Layla
2012-01-01
The call for malaria control, over the last century, marked a new epoch in the history of this disease. Many control strategies targeting either the Plasmodium parasite or the Anopheles vector were shown to be effective. Yet, the emergence of drug resistant parasites and insecticide resistant mosquito strains, along with numerous health, environmental, and ecological side effects of many chemical agents, highlighted the need to develop alternative tools that either complement or substitute conventional malaria control approaches. The use of biological means is considered a fundamental part of the recently launched malaria eradication program and has so far shown promising results, although this approach is still in its infancy. This review presents an overview of the most promising biological control tools for malaria eradication, namely fungi, bacteria, larvivorous fish, parasites, viruses and nematodes. PMID:23105979
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Global investment targets for malaria control and elimination between 2016 and 2030
Patouillard, Edith; Griffin, Jamie; Bhatt, Samir; Ghani, Azra; Cibulskis, Richard
2017-01-01
Background Access to malaria control interventions falls short of universal health coverage. The Global Technical Strategy for malaria targets at least 90% reduction in case incidence and mortality rates, and elimination in 35 countries by 2030. The potential to reach these targets will be determined in part by investments in malaria. This study estimates the financing required for malaria control and elimination over the 2016–2030 period. Methods A mathematical transmission model was used to explore the impact of increasing intervention coverage on burden and costs. The cost analysis took a public provider perspective covering all 97 malaria endemic countries and territories in 2015. All control interventions currently recommended by the WHO were considered. Cost data were sourced from procurement databases, the peer-reviewed literature, national malaria strategic plans, the WHO-CHOICE project and key informant interviews. Results Annual investments of $6.4 billion (95% uncertainty interval (UI $4.5–$9.0 billion)) by 2020, $7.7 billion (95% UI $5.4–$10.9 billion) by 2025 and $8.7 billion (95% UI $6.0–$12.3 billion) by 2030 will be required to reach the targets set in the Global Technical Strategy. These are equivalent to annual investment per person at risk of malaria of US$3.90 by 2020, US$4.30 by 2025 and US$4.40 by 2030, compared with US$2.30 if interventions were sustained at current coverage levels. The 20 countries with the highest burden in 2015 will require 88% of the total investment. Conclusions Given the challenges in increasing domestic and international funding, the efficient use of currently available resources should be a priority. PMID:29242750
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Mharakurwa, Sungano; Mutambu, Susan L; Mberikunashe, Joseph; Thuma, Philip E; Moss, William J; Mason, Peter R
2013-07-01
To better understand trends in the burden of malaria and their temporal relationship to control activities, a survey was conducted to assess reported cases of malaria and malaria control activities in Mutasa District, Zimbabwe. Data on reported malaria cases were abstracted from available records at all three district hospitals, three rural hospitals and 25 rural health clinics in Mutasa District from 2003 to 2011. Malaria control interventions were scaled up through the support of the Roll Back Malaria Partnership, the Global Fund to Fight AIDS, Tuberculosis and Malaria, and The President's Malaria Initiative. The recommended first-line treatment regimen changed from chloroquine or a combination of chloroquine plus sulphadoxine/pyrimethamine to artemisinin-based combination therapy, the latter adopted by 70%, 95% and 100% of health clinics by 2008, 2009 and 2010, respectively. Diagnostic capacity improved, with rapid diagnostic tests (RDTs) available in all health clinics by 2008. Vector control consisted of indoor residual spraying and distribution of long-lasting insecticidal nets. The number of reported malaria cases initially increased from levels in 2003 to a peak in 2008 but then declined 39% from 2008 to 2010. The proportion of suspected cases of malaria in older children and adults remained high, ranging from 75% to 80%. From 2008 to 2010, the number of RDT positive cases of malaria decreased 35% but the decrease was greater for children younger than five years of age (60%) compared to older children and adults (26%). The burden of malaria in Mutasa District decreased following the scale up of malaria control interventions. However, the persistent high number of cases in older children and adults highlights the need for strategies to identify locally effective control measures that target all age groups.
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Malaria Distribution, Prevalence, Drug Resistance and Control in Indonesia
Elyazar, Iqbal R.F.; Hay, Simon I.; Baird, J. Kevin
2011-01-01
Approximately 230 million people live in Indonesia. The country is also home to over 20 anopheline vectors of malaria which transmit all four of the species of Plasmodium that routinely infect humans. A complex mosaic of risk of infection across this 5000-km-long archipelago of thousands of islands and distinctive habitats seriously challenges efforts to control malaria. Social, economic and political dimensions contribute to these complexities. This chapter examines malaria and its control in Indonesia, from the earliest efforts by malariologists of the colonial Netherlands East Indies, through the Global Malaria Eradication Campaign of the 1950s, the tumult following the coup d’état of 1965, the global resurgence of malaria through the 1980s and 1990s and finally through to the decentralization of government authority following the fall of the authoritarian Soeharto regime in 1998. We detail important methods of control and their impact in the context of the political systems that supported them. We examine prospects for malaria control in contemporary decentralized and democratized Indonesia with multidrug-resistant malaria and greatly diminished capacities for integrated malaria control management programs. PMID:21295677
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2010-01-01
Background In Vietnam, malaria is becoming progressively restricted to specific foci where human and vector characteristics alter the known malaria epidemiology, urging for alternative or adapted control strategies. Long-lasting insecticidal hammocks (LLIH) were designed and introduced in Ninh Thuan province, south-central Vietnam, to control malaria in the specific context of forest malaria. An entomological study in this specific forested environment was conducted to assess the behavioural patterns of forest and village vectors and to assess the spatio-temporal risk factors of malaria transmission in the province. Methods Five entomological surveys were conducted in three villages in Ma Noi commune and in five villages in Phuoc Binh commune in Ninh Thuan Province, south-central Vietnam. Collections were made inside the village, at the plot near the slash-and-burn fields in the forest and on the way to the forest. All collected mosquito species were subjected to enzyme-linked immunosorbent assay (ELISA) to detect Plasmodium in the head-thoracic portion of individual mosquitoes after morphological identification. Collection data were analysed by use of correspondence and multivariate analyses. Results The mosquito density in the study area was low with on average 3.7 anopheline bites per man-night and 17.4 culicine bites per man-night. Plasmodium-infected mosquitoes were only found in the forest and on the way to the forest. Malaria transmission in the forested malaria foci was spread over the entire night, from dusk to dawn, but was most intense in the early evening as nine of the 13 Plasmodium positive bites occurred before 21H. The annual entomological inoculation rate of Plasmodium falciparum was 2.2 infective bites per person-year to which Anopheles dirus s.s. and Anopheles minimus s.s. contributed. The Plasmodium vivax annual entomological inoculation rate was 2.5 infective bites per person-year with Anopheles sawadwongporni, Anopheles dirus s.s. and
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Obiero, Joshua M.; Shekalaghe, Seif; Hermsen, Cornelus C.; Mpina, Maxmillian; Bijker, Else M.; Roestenberg, Meta; Teelen, Karina; Billingsley, Peter F.; Sim, B. Kim Lee; James, Eric R.; Daubenberger, Claudia A.; Hoffman, Stephen L.; Abdulla, Salim
2015-01-01
To understand the effect of previous malaria exposure on antiparasite immune responses is important for developing successful immunization strategies. Controlled human malaria infections (CHMIs) using cryopreserved Plasmodium falciparum sporozoites provide a unique opportunity to study differences in acquisition or recall of antimalaria immune responses in individuals from different transmission settings and genetic backgrounds. In this study, we compared antiparasite humoral and cellular immune responses in two cohorts of malaria-naive Dutch volunteers and Tanzanians from an area of low malarial endemicity, who were subjected to the identical CHMI protocol by intradermal injection of P. falciparum sporozoites. Samples from both trials were analyzed in parallel in a single center to ensure direct comparability of immunological outcomes. Within the Tanzanian cohort, we distinguished one group with moderate levels of preexisting antibodies to asexual P. falciparum lysate and another that, based on P. falciparum serology, resembled the malaria-naive Dutch cohort. Positive P. falciparum serology at baseline was associated with a lower parasite density at first detection by quantitative PCR (qPCR) after CHMI than that for Tanzanian volunteers with negative serology. Post-CHMI, both Tanzanian groups showed a stronger increase in anti-P. falciparum antibody titers than Dutch volunteers, indicating similar levels of B-cell memory independent of serology. In contrast to the Dutch, Tanzanians failed to increase P. falciparum-specific in vitro recall gamma interferon (IFN-γ) production after CHMI, and innate IFN-γ responses were lower in P. falciparum lysate-seropositive individuals than in seronegative individuals. In conclusion, positive P. falciparum lysate serology can be used to identify individuals with better parasite control but weaker IFN-γ responses in circulating lymphocytes, which may help to stratify volunteers in future CHMI trials in areas where malaria is
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Modelling malaria control by introduction of larvivorous fish.
Lou, Yijun; Zhao, Xiao-Qiang
2011-10-01
Malaria creates serious health and economic problems which call for integrated management strategies to disrupt interactions among mosquitoes, the parasite and humans. In order to reduce the intensity of malaria transmission, malaria vector control may be implemented to protect individuals against infective mosquito bites. As a sustainable larval control method, the use of larvivorous fish is promoted in some circumstances. To evaluate the potential impacts of this biological control measure on malaria transmission, we propose and investigate a mathematical model describing the linked dynamics between the host-vector interaction and the predator-prey interaction. The model, which consists of five ordinary differential equations, is rigorously analysed via theories and methods of dynamical systems. We derive four biologically plausible and insightful quantities (reproduction numbers) that completely determine the community composition. Our results suggest that the introduction of larvivorous fish can, in principle, have important consequences for malaria dynamics, but also indicate that this would require strong predators on larval mosquitoes. Integrated strategies of malaria control are analysed to demonstrate the biological application of our developed theory.
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Costs and cost-effectiveness of malaria control interventions - a systematic review
2011-01-01
Background The control and elimination of malaria requires expanded coverage of and access to effective malaria control interventions such as insecticide-treated nets (ITNs), indoor residual spraying (IRS), intermittent preventive treatment (IPT), diagnostic testing and appropriate treatment. Decisions on how to scale up the coverage of these interventions need to be based on evidence of programme effectiveness, equity and cost-effectiveness. Methods A systematic review of the published literature on the costs and cost-effectiveness of malaria interventions was undertaken. All costs and cost-effectiveness ratios were inflated to 2009 USD to allow comparison of the costs and benefits of several different interventions through various delivery channels, across different geographical regions and from varying costing perspectives. Results Fifty-five studies of the costs and forty three studies of the cost-effectiveness of malaria interventions were identified, 78% of which were undertaken in sub-Saharan Africa, 18% in Asia and 4% in South America. The median financial cost of protecting one person for one year was $2.20 (range $0.88-$9.54) for ITNs, $6.70 (range $2.22-$12.85) for IRS, $0.60 (range $0.48-$1.08) for IPT in infants, $4.03 (range $1.25-$11.80) for IPT in children, and $2.06 (range $0.47-$3.36) for IPT in pregnant women. The median financial cost of diagnosing a case of malaria was $4.32 (range $0.34-$9.34). The median financial cost of treating an episode of uncomplicated malaria was $5.84 (range $2.36-$23.65) and the median financial cost of treating an episode of severe malaria was $30.26 (range $15.64-$137.87). Economies of scale were observed in the implementation of ITNs, IRS and IPT, with lower unit costs reported in studies with larger numbers of beneficiaries. From a provider perspective, the median incremental cost effectiveness ratio per disability adjusted life year averted was $27 (range $8.15-$110) for ITNs, $143 (range $135-$150) for IRS, and
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Present status of malaria control in Asia
Dy, F. J.
1954-01-01
The author summarizes the information given by 13 governments—Afghanistan, Burma, Ceylon, China, India, Indonesia, Malaya, Netherlands New Guinea, Philippines, Portuguese India, Sarawak, Thailand, and Viet Nam—on their existing and proposed malaria-control programmes in response to a questionnaire prepared by WHO for discussion at the First Asian Malaria Conference, which was held in Bangkok in September 1953. Although in late 1953 nearly 46.5 million of the 271 million people living in malarious regions were protected against the disease, more than 224 million others were still unprotected. It is noted that residual-insecticide spraying—the basis of most campaigns—has significantly reduced spleen- and parasite-rates; that the minor opposition to spraying initially encountered in some places quickly disappeared as the benefits became apparent; that malaria control has resulted in general improvements in public health and has promoted socio-economic development; that anopheline resistance to the insecticides used has not been observed; that ten governments voiced the need for indoctrination of public officials concerning malaria control; and that there is a trend among governments to make financial provision for long-term malaria-control schemes. PMID:13209318
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History of malaria control in Tajikistan and rapid malaria appraisal in an agro-ecological setting.
Matthys, Barbara; Sherkanov, Tohir; Karimov, Saifudin S; Khabirov, Zamonidin; Mostowlansky, Till; Utzinger, Jürg; Wyss, Kaspar
2008-10-26
Reported malaria cases in rice growing areas in western Tajikistan were at the root of a rapid appraisal of the local malaria situation in a selected agro-ecological setting where only scarce information was available. The rapid appraisal was complemented by a review of the epidemiology and control of malaria in Tajikistan and Central Asia from 1920 until today. Following a resurgence in the 1990s, malaria transmission has been reduced considerably in Tajikistan as a result of concerted efforts by the government and international agencies. The goal for 2015 is transmission interruption, with control interventions and surveillance currently concentrated in the South, where foci of Plasmodium vivax and Plasmodium falciparum persist. The rapid malaria appraisal was carried out in six communities of irrigated rice cultivation during the peak of malaria transmission (August/September 2007) in western Tajikistan. In a cross-sectional survey, blood samples were taken from 363 schoolchildren and examined for Plasmodium under a light microscope. A total of 56 farmers were interviewed about agricultural activities and malaria. Potential Anopheles breeding sites were characterized using standardized procedures. A literature review on the epidemiology and control of malaria in Tajikistan was conducted. One case of P. vivax was detected among the 363 schoolchildren examined (0.28%). The interviewees reported to protect themselves against mosquito bites and used their own concepts on fever conditions, which do not distinguish between malaria and other diseases. Three potential malaria vectors were identified, i.e. Anopheles superpictus, Anopheles pulcherrimus and Anopheles hyrcanus in 58 of the 73 breeding sites examined (79.5%). Rice paddies, natural creeks and man-made ponds were the most important Anopheles habitats. The presence of malaria vectors and parasite reservoirs, low awareness of, and protection against malaria in the face of population movements and inadequate
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New treatment policy of malaria as a part of malaria control program in Indonesia.
Kusriastuti, Rita; Surya, Asik
2012-07-01
Malaria control program is one of the oldest program in the Ministry of Health (MoH) Republic of Indonesia. Started with effort to eradicate malaria in 1959 through Malaria Eradication Command well known as KOPEM (Komando Pembasmian Malaria) then it evolves to Malaria Control Program, Roll Back Malaria Program, and the current Malaria Elimination Program. In terms of diagnostic and treatment, the policy has formulated by strictly follow evidence-based principles as well as technical guided from World Health Organization (WHO). In 2004, based on numerous researches conducted in Indonesia the use of chloroquine was stopped and artemisinin-based combination therapy (ACT) was then initiated. For severe cases the use of intravenous (iv) Artesunate for cases treated in hospitals and intramuscular (im) Arthemeter for cases treated in the primary care setting were also introduced. ACT, Artesunate iv, and Artemether im, all are provided nationwide through the procurement system. For radical treatment, the recommendation in Indonesia is to add primaquine (PQ) to ACT for Plasmodium vivax and Plasmodium ovale infections to prevent relapses and for Plasmodium Falciparum infection to kill the gametocytes. These recommendations put hope to reduce malaria mortality to zero and eventually with other interventions will eliminate malaria from the country by 2030. The dissemination of this information is important for the policy to apply in practice across the country.
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Radar Monitoring of Wetlands for Malaria Control
NASA Technical Reports Server (NTRS)
Pope, Kevin O.
1997-01-01
Malaria is the most important vector-borne tropical disease (Collins and Paskewitz, 1995) and there is no simple and universally applicable form of vector control. While new methods such as malaria vaccine or genetic manipulation of mosquitoes are being explored in the laboratories, the need for more field research on malaria transmission remains very strong. For the foreseeable future many malaria programs must focus on controlling the vector, the anopheline mosquito, often under the specter of shrinking budgets. Therefore information on which human populations are at the greatest risk is especially valuable when allocating scarce resources. The goal of the Radar Monitoring of Wetlands for Malaria Control Project is to demonstrate the feasibility of using Radarsat or other comparable satellite radar imaging systems to determine where and when human populations are at greatest risk for contracting malaria. The study area is northern Belize, a region with abundant wetlands and a potentially serious malaria problem. A key aspect of this study is the analysis of multi-temporal satellite imagery to track seasonal flooding of anopheline mosquito breeding sites. Radarsat images of the test site in Belize have been acquired one to three times a month over the last year, however,, to date only one processed image has been received from the Alaska SAR Facility for analysis. Therefore analysis at this stage is focussed on determining the radar backscatter characteristics of known anopheline breeding sites, with future work to be dedicated toward seasonal changes.
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Current vector control challenges in the fight against malaria.
Benelli, Giovanni; Beier, John C
2017-10-01
The effective and eco-friendly control of Anopheles vectors plays a key role in any malaria management program. Integrated Vector Management (IVM) suggests making use of the full range of vector control tools available. The strategies for IVM require novel technologies to control outdoor transmission of malaria. Despite the wide number of promising control tools tested against mosquitoes, current strategies for malaria vector control used in most African countries are not sufficient to achieve successful malaria control. The majority of National Malaria Control Programs in Africa still rely on indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). These methods reduce malaria incidence but generally have little impact on malaria prevalence. In addition to outdoor transmission, growing levels of insecticide resistance in targeted vectors threaten the efficacy of LLINs and IRS. Larvicidal treatments can be useful, but are not recommended for rural areas. The research needed to improve the quality and delivery of mosquito vector control should focus on (i) optimization of processes and methods for vector control delivery; (ii) monitoring of vector populations and biting activity with reliable techniques; (iii) the development of effective and eco-friendly tools to reduce the burden or locally eliminate malaria and other mosquito-borne diseases; (iv) the careful evaluation of field suitability and efficacy of new mosquito control tools to prove their epidemiological impact; (v) the continuous monitoring of environmental changes which potentially affect malaria vector populations; (vi) the cooperation among different disciplines, with main emphasis on parasitology, tropical medicine, ecology, entomology, and ecotoxicology. A better understanding of behavioral ecology of malaria vectors is required. Key ecological obstacles that limit the effectiveness of vector control include the variation in mosquito behavior, development of insecticide resistance
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Cost effective malaria risk control using remote sensing and environmental data
NASA Astrophysics Data System (ADS)
Rahman, Md. Z.; Roytman, Leonid; Kadik, Abdel Hamid
2012-06-01
Malaria transmission in many part of the world specifically in Bangladesh and southern African countries is unstable and epidemic. An estimate of over a million cases is reported annually. Malaria is heterogeneous, potentially due to variations in ecological settings, socio-economic status, land cover, and agricultural practices. Malaria control only relies on treatment and supply of bed networks. Drug resistance to these diseases is widespread. Vector control is minimal. Malaria control in those countries faces many formidable challenges such as inadequate accessibility to effective treatment, lack of trained manpower, inaccessibility of endemic areas, poverty, lack of education, poor health infrastructure and low health budgets. Health facilities for malaria management are limited, surveillance is inadequate, and vector control is insufficient. Control can only be successful if the right methods are used at the right time in the right place. This paper aims to improve malaria control by developing malaria risk maps and risk models using satellite remote sensing data by identifying, assessing, and mapping determinants of malaria associated with environmental, socio-economic, malaria control, and agricultural factors.
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The economics of malaria control and elimination: a systematic review.
Shretta, Rima; Avanceña, Anton L V; Hatefi, Arian
2016-12-12
Declining donor funding and competing health priorities threaten the sustainability of malaria programmes. Elucidating the cost and benefits of continued investments in malaria could encourage sustained political and financial commitments. The evidence, although available, remains disparate. This paper reviews the existing literature on the economic and financial cost and return of malaria control, elimination and eradication. A review of articles that were published on or before September 2014 on the cost and benefits of malaria control and elimination was performed. Studies were classified based on their scope and were analysed according to two major categories: cost of malaria control and elimination to a health system, and cost-benefit studies. Only studies involving more than two control or elimination interventions were included. Outcomes of interest were total programmatic cost, cost per capita, and benefit-cost ratios (BCRs). All costs were converted to 2013 US$ for standardization. Of the 6425 articles identified, 54 studies were included in this review. Twenty-two were focused on elimination or eradication while 32 focused on intensive control. Forty-eight per cent of studies included in this review were published on or after 2000. Overall, the annual per capita cost of malaria control to a health system ranged from $0.11 to $39.06 (median: $2.21) while that for malaria elimination ranged from $0.18 to $27 (median: $3.00). BCRs of investing in malaria control and elimination ranged from 2.4 to over 145. Overall, investments needed for malaria control and elimination varied greatly amongst the various countries and contexts. In most cases, the cost of elimination was greater than the cost of control. At the same time, the benefits of investing in malaria greatly outweighed the costs. While the cost of elimination in most cases was greater than the cost of control, the benefits greatly outweighed the cost. Information from this review provides guidance to
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Application of loop analysis for evaluation of malaria control interventions.
Yasuoka, Junko; Jimba, Masamine; Levins, Richard
2014-04-09
Despite continuous efforts and recent rapid expansion in the financing and implementation of malaria control interventions, malaria still remains one of the most devastating global health issues. Even in countries that have been successful in reducing the incidence of malaria, malaria control is becoming more challenging because of the changing epidemiology of malaria and waning community participation in control interventions. In order to improve the effectiveness of interventions and to promote community understanding of the necessity of continued control efforts, there is an urgent need to develop new methodologies that examine the mechanisms by which community-based malaria interventions could reduce local malaria incidence. This study demonstrated how the impact of community-based malaria control interventions on malaria incidence can be examined in complex systems by qualitative analysis combined with an extensive review of literature. First, sign digraphs were developed through loop analysis to analyse seven interventions: source reduction, insecticide/larvicide use, biological control, treatment with anti-malarials, insecticide-treated mosquito net/long-lasting insecticidal net, non-chemical personal protection measures, and educational intervention. Then, for each intervention, the sign digraphs and literature review were combined to analyse a variety of pathways through which the intervention can influence local malaria incidence as well as interactions between variables involved in the system. Through loop analysis it is possible to see whether increases in one variable qualitatively increases or decreases other variables or leaves them unchanged and the net effect of multiple, interacting variables. Qualitative analysis, specifically loop analysis, can be a useful tool to examine the impact of community-based malaria control interventions. Without relying on numerical data, the analysis was able to describe pathways through which each intervention could
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Hydrological and geomorphological controls of malaria transmission
NASA Astrophysics Data System (ADS)
Smith, M. W.; Macklin, M. G.; Thomas, C. J.
2013-01-01
Malaria risk is linked inextricably to the hydrological and geomorphological processes that form vector breeding sites. Yet environmental controls of malaria transmission are often represented by temperature and rainfall amounts, ignoring hydrological and geomorphological influences altogether. Continental-scale studies incorporate hydrology implicitly through simple minimum rainfall thresholds, while community-scale coupled hydrological and entomological models do not represent the actual diversity of the mosquito vector breeding sites. The greatest range of malaria transmission responses to environmental factors is observed at the catchment scale where seemingly contradictory associations between rainfall and malaria risk can be explained by hydrological and geomorphological processes that govern surface water body formation and persistence. This paper extends recent efforts to incorporate ecological factors into malaria-risk models, proposing that the same detailed representation be afforded to hydrological and, at longer timescales relevant for predictions of climate change impacts, geomorphological processes. We review existing representations of environmental controls of malaria and identify a range of hydrologically distinct vector breeding sites from existing literature. We illustrate the potential complexity of interactions among hydrology, geomorphology and vector breeding sites by classifying a range of water bodies observed in a catchment in East Africa. Crucially, the mechanisms driving surface water body formation and destruction must be considered explicitly if we are to produce dynamic spatial models of malaria risk at catchment scales.
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Controlled Human Malaria Infection: Applications, Advances, and Challenges.
Stanisic, Danielle I; McCarthy, James S; Good, Michael F
2018-01-01
Controlled human malaria infection (CHMI) entails deliberate infection with malaria parasites either by mosquito bite or by direct injection of sporozoites or parasitized erythrocytes. When required, the resulting blood-stage infection is curtailed by the administration of antimalarial drugs. Inducing a malaria infection via inoculation with infected blood was first used as a treatment (malariotherapy) for neurosyphilis in Europe and the United States in the early 1900s. More recently, CHMI has been applied to the fields of malaria vaccine and drug development, where it is used to evaluate products in well-controlled early-phase proof-of-concept clinical studies, thus facilitating progression of only the most promising candidates for further evaluation in areas where malaria is endemic. Controlled infections have also been used to immunize against malaria infection. Historically, CHMI studies have been restricted by the need for access to insectaries housing infected mosquitoes or suitable malaria-infected individuals. Evaluation of vaccine and drug candidates has been constrained in these studies by the availability of a limited number of Plasmodium falciparum isolates. Recent advances have included cryopreservation of sporozoites, the manufacture of well-characterized and genetically distinct cultured malaria cell banks for blood-stage infection, and the availability of Plasmodium vivax -specific reagents. These advances will help to accelerate malaria vaccine and drug development by making the reagents for CHMI more widely accessible and also enabling a more rigorous evaluation with multiple parasite strains and species. Here we discuss the different applications of CHMI, recent advances in the use of CHMI, and ongoing challenges for consideration. Copyright © 2017 American Society for Microbiology.
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Human movement data for malaria control and elimination strategic planning.
Pindolia, Deepa K; Garcia, Andres J; Wesolowski, Amy; Smith, David L; Buckee, Caroline O; Noor, Abdisalan M; Snow, Robert W; Tatem, Andrew J
2012-06-18
Recent increases in funding for malaria control have led to the reduction in transmission in many malaria endemic countries, prompting the national control programmes of 36 malaria endemic countries to set elimination targets. Accounting for human population movement (HPM) in planning for control, elimination and post-elimination surveillance is important, as evidenced by previous elimination attempts that were undermined by the reintroduction of malaria through HPM. Strategic control and elimination planning, therefore, requires quantitative information on HPM patterns and the translation of these into parasite dispersion. HPM patterns and the risk of malaria vary substantially across spatial and temporal scales, demographic and socioeconomic sub-groups, and motivation for travel, so multiple data sets are likely required for quantification of movement. While existing studies based on mobile phone call record data combined with malaria transmission maps have begun to address within-country HPM patterns, other aspects remain poorly quantified despite their importance in accurately gauging malaria movement patterns and building control and detection strategies, such as cross-border HPM, demographic and socioeconomic stratification of HPM patterns, forms of transport, personal malaria protection and other factors that modify malaria risk. A wealth of data exist to aid filling these gaps, which, when combined with spatial data on transport infrastructure, traffic and malaria transmission, can answer relevant questions to guide strategic planning. This review aims to (i) discuss relevant types of HPM across spatial and temporal scales, (ii) document where datasets exist to quantify HPM, (iii) highlight where data gaps remain and (iv) briefly put forward methods for integrating these datasets in a Geographic Information System (GIS) framework for analysing and modelling human population and Plasmodium falciparum malaria infection movements.
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Human movement data for malaria control and elimination strategic planning
2012-01-01
Recent increases in funding for malaria control have led to the reduction in transmission in many malaria endemic countries, prompting the national control programmes of 36 malaria endemic countries to set elimination targets. Accounting for human population movement (HPM) in planning for control, elimination and post-elimination surveillance is important, as evidenced by previous elimination attempts that were undermined by the reintroduction of malaria through HPM. Strategic control and elimination planning, therefore, requires quantitative information on HPM patterns and the translation of these into parasite dispersion. HPM patterns and the risk of malaria vary substantially across spatial and temporal scales, demographic and socioeconomic sub-groups, and motivation for travel, so multiple data sets are likely required for quantification of movement. While existing studies based on mobile phone call record data combined with malaria transmission maps have begun to address within-country HPM patterns, other aspects remain poorly quantified despite their importance in accurately gauging malaria movement patterns and building control and detection strategies, such as cross-border HPM, demographic and socioeconomic stratification of HPM patterns, forms of transport, personal malaria protection and other factors that modify malaria risk. A wealth of data exist to aid filling these gaps, which, when combined with spatial data on transport infrastructure, traffic and malaria transmission, can answer relevant questions to guide strategic planning. This review aims to (i) discuss relevant types of HPM across spatial and temporal scales, (ii) document where datasets exist to quantify HPM, (iii) highlight where data gaps remain and (iv) briefly put forward methods for integrating these datasets in a Geographic Information System (GIS) framework for analysing and modelling human population and Plasmodium falciparum malaria infection movements. PMID:22703541
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Malaria in South Asia: Prevalence and control
Kumar, Ashwani; Chery, Laura; Biswas, Chinmoy; Dubhashi, Nagesh; Dutta, Prafulla; Dua, Virendra Kumar; Kacchap, Mridula; Kakati, Sanjeeb; Khandeparkar, Anar; Kour, Dalip; Mahajanj, Satish N.; Maji, Ardhendu; Majumder, Partha; Mohanta, Jagadish; Mohapatra, Pradyumna K.; Narayanasamy, Krishnamoorthy; Roy, Krishnangshu; Shastri, Jayanthi; Valecha, Neena; Vikash, Rana; Wani, Reena; White, John; Rathod, Pradipsinh K
2013-01-01
The “Malaria Evolution in South Asia” (MESA) program project is an International Center of Excellence for Malaria Research (ICEMR) sponsored by the US National Institutes of Health. This US–India collaborative program will study the origin of genetic diversity of malaria parasites and their selection on the Indian subcontinent. This knowledge should contribute to a better understanding of unexpected disease outbreaks and unpredictable disease presentations from Plasmodium falciparum and Plasmodium vivax infections. In this first of two reviews, we highlight malaria prevalence in India. In particular, we draw attention to variations in distribution of different human-parasites and different vectors, variation in drug resistance traits, and multiple forms of clinical presentations. Uneven malaria severity in India is often attributed to large discrepancies in health care accessibility as well as human migrations within the country and across neighboring borders. Poor access to health care goes hand in hand with poor reporting from some of the same areas, combining to possibly distort disease prevalence and death from malaria in some parts of India. Corrections are underway in the form of increased resources for disease control, greater engagement of village-level health workers for early diagnosis and treatment, and possibly new public–private partnerships activities accompanying traditional national malaria control programs in the most severely affected areas. A second accompanying review raises the possibility that, beyond uneven health care, evolutionary pressures may alter malaria parasites in ways that contribute to severe disease in India, particularly in the NE corridor of India bordering Myanmar Narayanasamy et al., 2012. PMID:22248528
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Ecologists can enable communities to implement malaria vector control in Africa
Mukabana, W Richard; Kannady, Khadija; Kiama, G Michael; Ijumba, Jasper N; Mathenge, Evan M; Kiche, Ibrahim; Nkwengulila, Gamba; Mboera, Leonard; Mtasiwa, Deo; Yamagata, Yoichi; van Schayk, Ingeborg; Knols, Bart GJ; Lindsay, Steven W; de Castro, Marcia Caldas; Mshinda, Hassan; Tanner, Marcel; Fillinger, Ulrike; Killeen, Gerry F
2006-01-01
Background Integrated vector management (IVM) for malaria control requires ecological skills that are very scarce and rarely applied in Africa today. Partnerships between communities and academic ecologists can address this capacity deficit, modernize the evidence base for such approaches and enable future scale up. Methods Community-based IVM programmes were initiated in two contrasting settings. On Rusinga Island, Western Kenya, community outreach to a marginalized rural community was achieved by University of Nairobi through a community-based organization. In Dar es Salaam, Tanzania, Ilala Municipality established an IVM programme at grassroots level, which was subsequently upgraded and expanded into a pilot scale Urban Malaria Control Programme with support from national academic institutes. Results Both programmes now access relevant expertise, funding and policy makers while the academic partners benefit from direct experience of community-based implementation and operational research opportunities. The communities now access up-to-date malaria-related knowledge and skills for translation into local action. Similarly, the academic partners have acquired better understanding of community needs and how to address them. Conclusion Until sufficient evidence is provided, community-based IVM remains an operational research activity. Researchers can never directly support every community in Africa so community-based IVM strategies and tactics will need to be incorporated into undergraduate teaching programmes to generate sufficient numbers of practitioners for national scale programmes. Academic ecologists at African institutions are uniquely positioned to enable the application of practical environmental and entomological skills for malaria control by communities at grassroots level and should be supported to fulfil this neglected role. PMID:16457724
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McCollum, Jeffrey T; Hanna, Refaat; Halbach, Alaina C; Cummings, James F
2015-01-01
From April 24 to 26, 2013, the Armed Forces Health Surveillance Center and the U.S. Africa Command cosponsored the inaugural meeting of the West Africa Malaria Task Force in Accra, Ghana. The meeting's purpose was to identify common challenges, explore regional and transcontinental collaborations, and to share knowledge about best practices in the fight against malaria in West Africa. Military representatives from Benin, Burkina Faso, Ghana, Liberia, Niger, Nigeria, Senegal, and Togo participated in the Task Force; various U.S. Government agencies were also represented, including the Department of Defense, the Centers for Disease Control and Prevention, and the Agency for International Development. African nation participants presented brief overviews of their military's malaria prevention and control measures, surveillance programs, diagnostic capabilities, and treatment regimens emphasizing gaps within existing programs. Representatives from U.S. agencies discussed activities and capabilities relevant for the region, challenges and lessons learned regarding malaria, and highlighted opportunities for enhanced partnerships to counter malaria in West Africa. This article summarizes the major conclusions of the Task Force meeting, identifies relevant focus areas for future Task Force activities, and outlines opportunities for further inclusion of West African militaries to improve regional malaria surveillance and control efforts. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.
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The history of 20th century malaria control in Peru
2013-01-01
Malaria has been part of Peruvian life since at least the 1500s. While Peru gave the world quinine, one of the first treatments for malaria, its history is pockmarked with endemic malaria and occasional epidemics. In this review, major increases in Peruvian malaria incidence over the past hundred years are described, as well as the human factors that have facilitated these events, and concerted private and governmental efforts to control malaria. Political support for malaria control has varied and unexpected events like vector and parasite resistance have adversely impacted morbidity and mortality. Though the ready availability of novel insecticides like DDT and efficacious medications reduced malaria to very low levels for a decade after the post eradication era, malaria reemerged as an important modern day challenge to Peruvian public health. Its reemergence sparked collaboration between domestic and international partners towards the elimination of malaria in Peru. PMID:24001096
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Garfield, R
1999-07-31
Throughout Central America, a traditional malaria control strategy (depending on heavy use of organic pesticides) became less effective during the 1970s. In Nicaragua, an alternative strategy, based on frequent local epidemiological assessments and community participation, was developed in the 1980s. Despite war-related social instability, and continuing vector resistance, this approach was highly successful. By the end of the contra war, there finally existed organisational and ecological conditions that favoured improved malaria control. Yet the expected improvements did not occur. In the 1990s, Nicaragua experienced its worst recorded malaria epidemics. This situation was partly caused by the country's macroeconomic structural adjustment programme. Volunteers now take fewer slides and provide less treatment, malaria control workers are less motivated by the spirit of public service, and some malaria control stations charge for diagnosis or treatment. To "roll back malaria", in Nicaragua at least, will require the roll-back of some erroneous aspects of structural adjustment.
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2010-01-01
Background In 2005, a nationwide survey estimated that 6.5% of households in Ethiopia owned an insecticide-treated net (ITN), 17% of households had been sprayed with insecticide, and 4% of children under five years of age with a fever were taking an anti-malarial drug. Similar to other sub-Saharan African countries scaling-up malaria interventions, the Government of Ethiopia set an ambitious national goal in 2005 to (i) provide 100% ITN coverage in malarious areas, with a mean of two ITNs per household; (ii) to scale-up indoor residual spraying of households with insecticide (IRS) to cover 30% of households targeted for IRS; and (iii) scale-up the provision of case management with rapid diagnostic tests (RDTs) and artemisinin-based combination therapy (ACT), particularly at the peripheral level. Methods A nationally representative malaria indicator survey (MIS) was conducted in Ethiopia between September and December 2007 to determine parasite and anaemia prevalence in the population at risk and to assess coverage, use and access to scaled-up malaria prevention and control interventions. The survey used a two-stage random cluster sample of 7,621 households in 319 census enumeration areas. A total of 32,380 people participated in the survey. Data was collected using standardized Roll Back Malaria Monitoring and Evaluation Reference Group MIS household and women's questionnaires, which were adapted to the local context. Results Data presented is for households in malarious areas, which according to the Ethiopian Federal Ministry of Health are defined as being located <2,000 m altitude. Of 5,083 surveyed households, 3,282 (65.6%) owned at least one ITN. In ITN-owning households, 53.2% of all persons had slept under an ITN the prior night, including 1,564/2,496 (60.1%) children <5 years of age, 1,891/3,009 (60.9%) of women 15 - 49 years of age, and 166/266 (65.7%) of pregnant women. Overall, 906 (20.0%) households reported to have had IRS in the past 12 months. Of 747
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Malaria Control and Elimination,1 Venezuela, 1800s–1970s
Villegas, Leopoldo; Udhayakumar, Venkatachalam
2014-01-01
Venezuela had the highest number of human malaria cases in Latin American before 1936. During 1891–1920, malaria was endemic to >600,000 km2 of this country; malaria death rates led to major population decreases during 1891–1920. No pathogen, including the influenza virus that caused the 1918 pandemic, caused more deaths than malaria during 1905–1945. Early reports of malaria eradication in Venezuela helped spark the world’s interest in global eradication. We describe early approaches to malaria epidemiology in Venezuela and how this country developed an efficient control program and an approach to eradication. Arnoldo Gabaldón was a key policy maker during this development process. He directed malaria control in Venezuela from the late 1930s to the end of the 1970s and contributed to malaria program planning of the World Health Organization. We discuss how his efforts helped reduce the incidence of malaria in Venezuela and how his approach diverged from World Health Organization guidelines.
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Malaria control and elimination, Venezuela, 1800s –1970s.
Griffing, Sean M; Villegas, Leopoldo; Udhayakumar, Venkatachalam
2014-10-01
Venezuela had the highest number of human malaria cases in Latin American before 1936. During 1891–1920,malaria was endemic to >600,000 km2 of this country; malaria death rates led to major population decreases during 1891–1920. No pathogen, including the influenza virus that caused the 1918 pandemic, caused more deaths than malaria during 1905–1945. Early reports of malaria eradication in Venezuela helped spark the world's interest in global eradication. We describe early approaches to malaria epidemiology in Venezuela and how this country developed an efficient control program and an approach to eradication.Arnoldo Gabaldón was a key policy maker during this development process. He directed malaria control in Venezuela from the late 1930s to the end of the 1970s and contributed to malaria program planning of the World Health Organization.We discuss how his efforts helped reduce the incidence of malaria in Venezuela and how his approach diverged from World Health Organization guidelines.
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Malaria in South Asia: prevalence and control.
Kumar, Ashwani; Chery, Laura; Biswas, Chinmoy; Dubhashi, Nagesh; Dutta, Prafulla; Dua, Virendra Kumar; Kacchap, Mridula; Kakati, Sanjeeb; Khandeparkar, Anar; Kour, Dalip; Mahajan, Satish N; Maji, Ardhendu; Majumder, Partha; Mohanta, Jagadish; Mohapatra, Pradyumna K; Narayanasamy, Krishnamoorthy; Roy, Krishnangshu; Shastri, Jayanthi; Valecha, Neena; Vikash, Rana; Wani, Reena; White, John; Rathod, Pradipsinh K
2012-03-01
The "Malaria Evolution in South Asia" (MESA) program project is an International Center of Excellence for Malaria Research (ICEMR) sponsored by the US National Institutes of Health. This US-India collaborative program will study the origin of genetic diversity of malaria parasites and their selection on the Indian subcontinent. This knowledge should contribute to a better understanding of unexpected disease outbreaks and unpredictable disease presentations from Plasmodium falciparum and Plasmodium vivax infections. In this first of two reviews, we highlight malaria prevalence in India. In particular, we draw attention to variations in distribution of different human-parasites and different vectors, variation in drug resistance traits, and multiple forms of clinical presentations. Uneven malaria severity in India is often attributed to large discrepancies in health care accessibility as well as human migrations within the country and across neighboring borders. Poor access to health care goes hand in hand with poor reporting from some of the same areas, combining to possibly distort disease prevalence and death from malaria in some parts of India. Corrections are underway in the form of increased resources for disease control, greater engagement of village-level health workers for early diagnosis and treatment, and possibly new public-private partnerships activities accompanying traditional national malaria control programs in the most severely affected areas. A second accompanying review raises the possibility that, beyond uneven health care, evolutionary pressures may alter malaria parasites in ways that contribute to severe disease in India, particularly in the NE corridor of India bordering Myanmar Narayanasamy et al., 2012. Copyright © 2012 Elsevier B.V. All rights reserved.
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Funding for malaria control 2006-2010: a comprehensive global assessment.
Pigott, David M; Atun, Rifat; Moyes, Catherine L; Hay, Simon I; Gething, Peter W
2012-07-28
The last decade has seen a dramatic increase in international and domestic funding for malaria control, coupled with important declines in malaria incidence and mortality in some regions of the world. As the ongoing climate of financial uncertainty places strains on investment in global health, there is an increasing need to audit the origin, recipients and geographical distribution of funding for malaria control relative to populations at risk of the disease. A comprehensive review of malaria control funding from international donors, bilateral sources and national governments was undertaken to reconstruct total funding by country for each year 2006 to 2010. Regions at risk from Plasmodium falciparum and/or Plasmodium vivax transmission were identified using global risk maps for 2010 and funding was assessed relative to populations at risk. Those nations with unequal funding relative to a regional average were identified and potential explanations highlighted, such as differences in national policies, government inaction or donor neglect. US$8.9 billion was disbursed for malaria control and elimination programmes over the study period. Africa had the largest levels of funding per capita-at-risk, with most nations supported primarily by international aid. Countries of the Americas, in contrast, were supported typically through national government funding. Disbursements and government funding in Asia were far lower with a large variation in funding patterns. Nations with relatively high and low levels of funding are discussed. Global funding for malaria control is substantially less than required. Inequity in funding is pronounced in some regions particularly when considering the distinct goals of malaria control and malaria elimination. Efforts to sustain and increase international investment in malaria control should be informed by evidence-based assessment of funding equity.
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Molecular entomology and prospects for malaria control.
Collins, F. H.; Kamau, L.; Ranson, H. A.; Vulule, J. M.
2000-01-01
During the past decade, the techniques of molecular and cell biology have been embraced by many scientists doing research on anopheline vectors of malaria parasites. Some of the most important research advances in molecular entomology have concerned the development of sophisticated molecular tools for procedures such as genetic and physical mapping and germ line transformation. Major advances have also been made in the study of specific biological processes such as insect defence against pathogens and the manner in which malaria parasites and their anopheline hosts interact during sporogony. One of the most important highlights of this research trend has been the emergence during the past year of a formal international Anopheles gambiae genome project, which at present includes investigators in several laboratories in Europe and the USA. Although much of this molecular research is directed towards the development of malaria control strategies that are probably many years from implementation, there are some important areas of molecular entomology that may have a more near-term impact on malaria control. We highlight developments over the past decade in three such areas that we believe can make important contributions to the development of near-term malaria control strategies. These areas are anopheline species identification, the detection and monitoring of insecticide susceptibility/resistance in wild anopheline populations and the determination of the genetic structure of anopheline populations. PMID:11196488
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Earth observation in support of malaria control and epidemiology: MALAREO monitoring approaches.
Franke, Jonas; Gebreslasie, Michael; Bauwens, Ides; Deleu, Julie; Siegert, Florian
2015-06-03
Malaria affects about half of the world's population, with the vast majority of cases occuring in Africa. National malaria control programmes aim to reduce the burden of malaria and its negative, socioeconomic effects by using various control strategies (e.g. vector control, environmental management and case tracking). Vector control is the most effective transmission prevention strategy, while environmental factors are the key parameters affecting transmission. Geographic information systems (GIS), earth observation (EO) and spatial modelling are increasingly being recognised as valuable tools for effective management and malaria vector control. Issues previously inhibiting the use of EO in epidemiology and malaria control such as poor satellite sensor performance, high costs and long turnaround times, have since been resolved through modern technology. The core goal of this study was to develop and implement the capabilities of EO data for national malaria control programmes in South Africa, Swaziland and Mozambique. High- and very high resolution (HR and VHR) land cover and wetland maps were generated for the identification of potential vector habitats and human activities, as well as geoinformation on distance to wetlands for malaria risk modelling, population density maps, habitat foci maps and VHR household maps. These products were further used for modelling malaria incidence and the analysis of environmental factors that favour vector breeding. Geoproducts were also transferred to the staff of national malaria control programmes in seven African countries to demonstrate how EO data and GIS can support vector control strategy planning and monitoring. The transferred EO products support better epidemiological understanding of environmental factors related to malaria transmission, and allow for spatio-temporal targeting of malaria control interventions, thereby improving the cost-effectiveness of interventions.
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Smithson, Paul; Florey, Lia; Salgado, S. Rene; Hershey, Christine L.; Masanja, Honorati; Bhattarai, Achuyt; Mwita, Alex; McElroy, Peter D.
2015-01-01
Background Mainland Tanzania scaled up multiple malaria control interventions between 1999 and 2010. We evaluated whether, and to what extent, reductions in all-cause under-five child mortality (U5CM) tracked with malaria control intensification during this period. Methods Four nationally representative household surveys permitted trend analysis for malaria intervention coverage, severe anemia (hemoglobin <8 g/dL) prevalence (SAP) among children 6–59 months, and U5CM rates stratified by background characteristics, age, and malaria endemicity. Prevalence of contextual factors (e.g., vaccination, nutrition) likely to influence U5CM were also assessed. Population attributable risk percentage (PAR%) estimates for malaria interventions and contextual factors that changed over time were used to estimate magnitude of impact on U5CM. Results Household ownership of insecticide-treated nets (ITNs) rose from near zero in 1999 to 64% (95% CI, 61.7–65.2) in 2010. Intermittent preventive treatment of malaria in pregnancy reached 26% (95% CI, 23.6–28.0) by 2010. Sulfadoxine-pyrimethamine replaced chloroquine in 2002 and artemisinin-based combination therapy was introduced in 2007. SAP among children 6–59 months declined 50% between 2005 (11.1%; 95% CI, 10.0–12.3%) and 2010 (5.5%; 95% CI, 4.7–6.4%) and U5CM declined by 45% between baseline (1995–9) and endpoint (2005–9), from 148 to 81 deaths/1000 live births, respectively. Mortality declined 55% among children 1–23 months of age in higher malaria endemicity areas. A large reduction in U5CM was attributable to ITNs (PAR% = 11) with other malaria interventions adding further gains. Multiple contextual factors also contributed to survival gains. Conclusion Marked declines in U5CM occurred in Tanzania between 1999 and 2010 with high impact from ITNs and ACTs. High-risk children (1–24 months of age in high malaria endemicity) experienced the greatest declines in mortality and SAP. Malaria control should remain a
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Xu, Jian-Wei; Liu, Hui; Zhang, Yu; Guo, Xiang-Rui; Wang, Jia-Zhi
2015-01-01
A retrospective case-control study was conducted to identify risk factors for border malaria in a malaria elimination setting of Yunnan Province, China. The study comprised 214 cases and 428 controls. The controls were individually matched to the cases on the basis of residence, age, and gender. In addition, statistical associations are based on matched analyses. The frequencies of imported, male, adult, and vivax malaria cases were respectively 201 (93.9%), 194 (90.7%), 210 (98.1%), and 176 (82.2%). Overnight stay in Myanmar within the prior month was independently associated with malaria infection (odds ratio [OR] 159.5, 95% confidence interval [CI] 75.1–338.9). In particular, stays in lowland and foothill (OR 5.5, 95% CI 2.5–11.8) or mid-hill (OR 42.8, 95% CI 5.1–319.8) areas, or near streamlets (OR 15.3, 95% CI 4.3–55.2) or paddy field or pools (OR10.1, 95% CI 4.4–55.8) were found to be independently associated with malaria. Neither forest exposure nor use of vector control measures was associated with malaria. In conclusion, travel to lowland and foothill or mid-hill hyperendemic areas, especially along the waterside in Myanmar, was found to be the highest risk factor for malaria. In considering the limitations of the study, further investigations are needed to identify the major determinants of malaria risk and develop new strategies for malaria elimination on China-Myanmar border. PMID:25601994
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yhdego, M.; Majura, P.
A review of the malaria control programs and the problem encountered in the United Republic of Tanzania since 1945 to the year 1986 is discussed. Buguruni, one of the squatter areas in the city of Dar es Salaam, is chosen as a case study in order to evaluate the economic advantage of engineering methods for the control of malaria infection. Although the initial capital cost of engineering methods may be high, the cost effectiveness requires a much lower financial burden of only about Tshs. 3 million compared with the conventional methods of larviciding and insecticiding which requires more than Tshs.more » 10 million. Finally, recommendations for the adoption of engineering methods are made concerning the upgrading of existing roads and footpaths in general with particular emphasis on drainage of large pools of water which serve as breeding sites for mosquitoes.« less
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DDT, global strategies, and a malaria control crisis in South America.
Roberts, D R; Laughlin, L L; Hsheih, P; Legters, L J
1997-01-01
Malaria is reemerging in endemic-disease countries of South America. We examined the rate of real growth in annual parasite indexes (API) by adjusting APIs for all years to the annual blood examination rate of 1965 for each country. The standardized APIs calculated for Brazil, Peru, Guyana, and for 18 other malaria-endemic countries of the Americas presented a consistent pattern of low rates up through the late 1970s, followed by geometric growth in malaria incidence in subsequent years. True growth in malaria incidence corresponds temporally with changes in global strategies for malaria control. Underlying the concordance of these events is a causal link between decreased spraying of homes with DDT and increased malaria; two regression models defining this link showed statistically significant negative relationships between APIs and house-spray rates. Separate analyses of data from 1993 to 1995 showed that countries that have recently discontinued their spray programs are reporting large increases in malaria incidence. Ecuador, which has increased use of DDT since 1993, is the only country reporting a large reduction (61%) in malaria rates since 1993. DDT use for malaria control and application of the Global Malaria Control Strategy to the Americas should be subjects of urgent national and international debate. We discuss the recent actions to ban DDT, the health costs of such a ban, perspectives on DDT use in agriculture versus malaria control, and costs versus benefits of DDT and alternative insecticides.
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DDT, global strategies, and a malaria control crisis in South America.
Roberts, D. R.; Laughlin, L. L.; Hsheih, P.; Legters, L. J.
1997-01-01
Malaria is reemerging in endemic-disease countries of South America. We examined the rate of real growth in annual parasite indexes (API) by adjusting APIs for all years to the annual blood examination rate of 1965 for each country. The standardized APIs calculated for Brazil, Peru, Guyana, and for 18 other malaria-endemic countries of the Americas presented a consistent pattern of low rates up through the late 1970s, followed by geometric growth in malaria incidence in subsequent years. True growth in malaria incidence corresponds temporally with changes in global strategies for malaria control. Underlying the concordance of these events is a causal link between decreased spraying of homes with DDT and increased malaria; two regression models defining this link showed statistically significant negative relationships between APIs and house-spray rates. Separate analyses of data from 1993 to 1995 showed that countries that have recently discontinued their spray programs are reporting large increases in malaria incidence. Ecuador, which has increased use of DDT since 1993, is the only country reporting a large reduction (61%) in malaria rates since 1993. DDT use for malaria control and application of the Global Malaria Control Strategy to the Americas should be subjects of urgent national and international debate. We discuss the recent actions to ban DDT, the health costs of such a ban, perspectives on DDT use in agriculture versus malaria control, and costs versus benefits of DDT and alternative insecticides. PMID:9284373
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Using Decision Analysis to Improve Malaria Control Policy Making
Kramer, Randall; Dickinson, Katherine L.; Anderson, Richard M.; Fowler, Vance G.; Miranda, Marie Lynn; Mutero, Clifford M.; Saterson, Kathryn A.; Wiener, Jonathan B.
2013-01-01
Malaria and other vector-borne diseases represent a significant and growing burden in many tropical countries. Successfully addressing these threats will require policies that expand access to and use of existing control methods, such as insecticide-treated bed nets and artemesinin combination therapies for malaria, while weighing the costs and benefits of alternative approaches over time. This paper argues that decision analysis provides a valuable framework for formulating such policies and combating the emergence and re-emergence of malaria and other diseases. We outline five challenges that policy makers and practitioners face in the struggle against malaria, and demonstrate how decision analysis can help to address and overcome these challenges. A prototype decision analysis framework for malaria control in Tanzania is presented, highlighting the key components that a decision support tool should include. Developing and applying such a framework can promote stronger and more effective linkages between research and policy, ultimately helping to reduce the burden of malaria and other vector-borne diseases. PMID:19356821
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Yeka, Adoke; Gasasira, Anne; Mpimbaza, Arthur; Achan, Jane; Nankabirwa, Joaniter; Nsobya, Sam; Staedke, Sarah G.; Donnelly, Martin J.; Wabwire-Mangen, Fred; Talisuna, Ambrose; Dorsey, Grant; Kamya, Moses R.; Rosenthal, Philip J.
2011-01-01
Malaria remains one of the leading health problems of the developing world, and Uganda bears a particularly large burden from the disease. Our understanding is limited by a lack of reliable data, but it is clear that the prevalence of malaria infection, incidence of disease, and mortality from severe malaria all remain very high. Uganda has made progress in implementing key malaria control measures, in particular distribution of insecticide impregnated bednets, indoor residual spraying of insecticides, utilization of artemisinin-based combination therapy to treat uncomplicated malaria, and provision of intermittent preventive therapy for pregnant women. However, despite enthusiasm regarding the potential for the elimination of malaria in other areas, there is no convincing evidence that the burden of malaria has decreased in Uganda in recent years. Major challenges to malaria control in Uganda include very high malaria transmission intensity, inadequate health care resources, a weak health system, inadequate understanding of malaria epidemiology and the impact of control interventions, increasing resistance of parasites to drugs and of mosquitoes to insecticides, inappropriate case management, inadequate utilization of drugs to prevent malaria, and inadequate epidemic preparedness and response. Despite these challenges, prospects for the control of malaria have improved, and with attention to underlying challenges, progress toward the control of malaria in Uganda can be expected. PMID:21420377
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[Contribution of remote sensing to malaria control].
Machault, V; Pages, F; Rogier, C
2009-04-01
Despite national and international efforts, malaria remains a major public health problem and the fight to control the disease is confronted by numerous hurdles. Study of space and time dynamics of malaria is necessary as a basis for making appropriate decision and prioritizing intervention including in areas where field data are rare and sanitary information systems are inadequate. Evaluation of malarial risk should also help anticipate the risk of epidemics as a basis for early warning systems. Since 1960-70 civilian satellites launched for earth observation have been providing information for the measuring or evaluating geo-climatic and anthropogenic factors related to malaria transmission and burden. Remotely sensed data gathered for several civilian or military studies have allowed setup of entomological, parasitological, and epidemiological risk models and maps for rural and urban areas. Mapping of human populations at risk has also benefited from remotely sensing. The results of the published studies show that remote sensing is a suitable tool for optimizing planning, efficacy and efficiency of malaria control.
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Hasegawa, Aya; Yasuoka, Junko; Ly, Po; Nguon, Chea; Jimba, Masamine
2013-08-23
Malaria and other communicable diseases remain major threats in developing countries. In Cambodia, village malaria workers (VMWs) have been providing malaria control services in remote villages to cope with the disease threats. In 2009, the VMW project integrated child health services into the original malaria control services. However, little has been studied about the utilization of VMWs' child health services. This study aimed to identify determinants of caregivers' VMW service utilization for childhood illness and caregivers' knowledge of malaria management. A cross-sectional study was conducted in 36 VMW villages of Kampot and Kampong Thom provinces in July-September 2012. An equal number of VMW villages with malaria control services only (M) and those with malaria control plus child health services (M+C) were selected from each province. Using structured questionnaires, 800 caregivers of children under five and 36 VMWs, one of the two VMWs who was providing VMW services in each study village were interviewed. Among the caregivers, 23% in M villages and 52% in M+C villages utilized VMW services for childhood illnesses. Determinants of caregivers' utilization of VMWs in M villages included their VMWs' length of experience (AOR = 11.80, 95% confidence interval [CI] = 4.46-31.19) and VMWs' service quality (AOR = 2.04, CI = 1.01-4.11). In M+C villages, VMWs' length of experience (AOR = 2.44, CI = 1.52-3.94) and caregivers' wealth index (AOR = 0.35, CI = 0.18-0.68) were associated with VMW service utilization. Meanwhile, better service quality of VMWs (AOR = 3.21, CI = 1.34-7.66) and caregivers' literacy (AOR = 9.91, CI = 4.66-21.05) were positively associated with caregivers' knowledge of malaria management. VMWs' service quality and length of experience are important determinants of caregivers' utilization of VMWs' child health services and their knowledge of malaria management. Caregivers are seeking VMWs' support for childhood illnesses even if they are
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Factors influencing malaria control policy-making in Kenya, Uganda and Tanzania.
Mutero, Clifford M; Kramer, Randall A; Paul, Christopher; Lesser, Adriane; Miranda, Marie Lynn; Mboera, Leonard E G; Kiptui, Rebecca; Kabatereine, Narcis; Ameneshewa, Birkinesh
2014-08-08
Policy decisions for malaria control are often difficult to make as decision-makers have to carefully consider an array of options and respond to the needs of a large number of stakeholders. This study assessed the factors and specific objectives that influence malaria control policy decisions, as a crucial first step towards developing an inclusive malaria decision analysis support tool (MDAST). Country-specific stakeholder engagement activities using structured questionnaires were carried out in Kenya, Uganda and Tanzania. The survey respondents were drawn from a non-random purposeful sample of stakeholders, targeting individuals in ministries and non-governmental organizations whose policy decisions and actions are likely to have an impact on the status of malaria. Summary statistics across the three countries are presented in aggregate. Important findings aggregated across countries included a belief that donor preferences and agendas were exerting too much influence on malaria policies in the countries. Respondents on average also thought that some relevant objectives such as engaging members of parliament by the agency responsible for malaria control in a particular country were not being given enough consideration in malaria decision-making. Factors found to influence decisions regarding specific malaria control strategies included donor agendas, costs, effectiveness of interventions, health and environmental impacts, compliance and/acceptance, financial sustainability, and vector resistance to insecticides. Malaria control decision-makers in Kenya, Uganda and Tanzania take into account health and environmental impacts as well as cost implications of different intervention strategies. Further engagement of government legislators and other policy makers is needed in order to increase funding from domestic sources, reduce donor dependence, sustain interventions and consolidate current gains in malaria.
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Malaria survey and malaria control detachments in the South-West Pacific Area in World War 2.
Crocker, Denton W
2009-01-01
Malaria among troops in the South-West Pacific Area (SWPA) in World War 2 affected the military effort to the degree that special units were formed to combat it. These malaria survey detachments (MSDs) and malaria control detachments (MCDs) were self-contained and so could move quickly to wherever their services were needed. In SWPA by 25 September 1944 there were 32 MSDs and 65 MCDs. Tables of organization called for 11 enlisted men in MSDs and MCDs, two officers in MSDs and one in MCDs. Detachments served throughout the SWPA. Detailed records of the 31st MSD show that in addition to antimalarial efforts it worked at control of scrub typhus, dengue and venereal disease, at reduction of rat populations and in experimental work involving DDT and schistosomiasis. Specific locations of the 31st MSD were New Guinea (3 sites), Morotai, Leyte, Mindoro, Okinawa and Japan. The detachment served overseas for 21 months. Experience in combating malaria in SWPA in World War 2 points to the need for better and continuous training of both medical and line officers in malaria prevention and control.
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Averting a malaria disaster: will insecticide resistance derail malaria control?
Hemingway, Janet; Ranson, Hilary; Magill, Alan; Kolaczinski, Jan; Fornadel, Christen; Gimnig, John; Coetzee, Maureen; Simard, Frederic; Roch, Dabiré K; Hinzoumbe, Clément Kerah; Pickett, John; Schellenberg, David; Gething, Peter; Hoppé, Mark; Hamon, Nicholas
2016-04-23
World Malaria Day 2015 highlighted the progress made in the development of new methods of prevention (vaccines and insecticides) and treatment (single dose drugs) of the disease. However, increasing drug and insecticide resistance threatens the successes made with existing methods. Insecticide resistance has decreased the efficacy of the most commonly used insecticide class of pyrethroids. This decreased efficacy has increased mosquito survival, which is a prelude to rising incidence of malaria and fatalities. Despite intensive research efforts, new insecticides will not reach the market for at least 5 years. Elimination of malaria is not possible without effective mosquito control. Therefore, to combat the threat of resistance, key stakeholders need to rapidly embrace a multifaceted approach including a reduction in the cost of bringing new resistance management methods to market and the streamlining of associated development, policy, and implementation pathways to counter this looming public health catastrophe. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Bijker, Else M; Sauerwein, Robert W; Bijker, Wiebe E
2016-02-01
Controlled human malaria infections are clinical trials in which healthy volunteers are deliberately infected with malaria under controlled conditions. Controlled human malaria infections are complex clinical trials: many different groups and institutions are involved, and several complex technologies are required to function together. This functioning together of technologies, people, and institutions is under special pressure because of potential risks to the volunteers. In this article, the authors use controlled human malaria infections as a strategic research site to study the use of control, the role of trust, and the interactions between trust and control in the construction of scientific knowledge. The authors argue that tandems of trust and control play a central role in the successful execution of clinical trials and the construction of scientific knowledge. More specifically, two aspects of tandems of trust and control will be highlighted: tandems are sites where trust and control coproduce each other, and tandems link the personal, the technical, and the institutional domains. Understanding tandems of trust and control results in setting some agendas for both clinical trial research and science and technology studies.
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Microsporidians as evolution-proof agents of malaria control?
Koella, Jacob C; Lorenz, Lena; Bargielowski, Irka
2009-01-01
Despite our efforts at malaria control, malaria remains one of our most serious and deadly diseases. The failure of control stems in part from the parasite's intense transmission in many areas and from the emergence and spread of resistance of the malaria parasites and their mosquito vectors against most of the chemicals used to attack them. New methods for control are desperately needed. However, new methods will be useful only if they are effective (i.e., decrease transmission substantially) and evolutionarily sustainable (i.e., evolution-proof, in that they prevent evolution from eroding efficacy). We suggest microsporidian parasites that infect mosquitoes could be potentially effective and sustainable agents for malaria control. They may be effective because they target several epidemiologically important traits: survival of larvae (and thus number of adult mosquitoes), adult longevity, biting rate and the development of malaria within the mosquitoes. Even if each trait is affected only moderately, the intensity of transmission can be reduced considerably. They may be evolution-proof, for the evolutionarily most important trait is juvenile survival, whereas the two epidemiologically most important factors are traits of the adult mosquito: biting rate and longevity. Under the intense microsporidian pressure of a control programme, it is likely (if not inevitable) that the larvae evolve to survive microsporidian infection. However, if this larval tolerance to microsporidians is genetically correlated with the adult traits, tolerant mosquitoes may not live as long and bite less frequently than microsporidian-sensitive ones. While such a trade-off has not been measured, combining several studies suggests indirectly a negative genetic correlation between larval tolerance and adult longevity. Therefore, evolution might not undermine control; rather it might increase its effectiveness. While the evolution of resistance may be inevitable, the failure of control need
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Hemingway, Janet; Shretta, Rima; Wells, Timothy N. C.; Bell, David; Djimdé, Abdoulaye A.; Achee, Nicole; Qi, Gao
2016-01-01
Progress made in malaria control during the past decade has prompted increasing global dialogue on malaria elimination and eradication. The product development pipeline for malaria has never been stronger, with promising new tools to detect, treat, and prevent malaria, including innovative diagnostics, medicines, vaccines, vector control products, and improved mechanisms for surveillance and response. There are at least 25 projects in the global malaria vaccine pipeline, as well as 47 medicines and 13 vector control products. In addition, there are several next-generation diagnostic tools and reference methods currently in development, with many expected to be introduced in the next decade. The development and adoption of these tools, bolstered by strategies that ensure rapid uptake in target populations, intensified mechanisms for information management, surveillance, and response, and continued financial and political commitment are all essential to achieving global eradication. PMID:26934361
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Hemingway, Janet; Shretta, Rima; Wells, Timothy N C; Bell, David; Djimdé, Abdoulaye A; Achee, Nicole; Qi, Gao
2016-03-01
Progress made in malaria control during the past decade has prompted increasing global dialogue on malaria elimination and eradication. The product development pipeline for malaria has never been stronger, with promising new tools to detect, treat, and prevent malaria, including innovative diagnostics, medicines, vaccines, vector control products, and improved mechanisms for surveillance and response. There are at least 25 projects in the global malaria vaccine pipeline, as well as 47 medicines and 13 vector control products. In addition, there are several next-generation diagnostic tools and reference methods currently in development, with many expected to be introduced in the next decade. The development and adoption of these tools, bolstered by strategies that ensure rapid uptake in target populations, intensified mechanisms for information management, surveillance, and response, and continued financial and political commitment are all essential to achieving global eradication.
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Nateghpour, M; Edrissian, Ghh; Raeisi, A; Motevalli-Haghi, A; Farivar, L; Mohseni, Gh; Rahimi-Froushani, A
2012-01-01
Malaria is still one of the most important infectious diseases in the world. The disease also is a public health problem in south and southeast of Iran. This study programmed to show the correlation between regular malaria microscopy training and refresher training courses and control of malaria in Iran. Three types of training courses were conducted in this programme including; five - day, ten - day and bimonthly training courses. Each of the training courses contained theoretical and practical sections and training impact was evaluated by practical examination and multiple-choice quizzes through pre and post tests. Distribution pattern of the participants in the training and refresher training courses showed that the most participants were from Sistan & Baluchistan and Hormozgan provinces where malaria is endemic and most cases of the infection come out from these malarious areas. A total of 695 identified individuals were participated in the training courses. A significant conversely correlation was found between conducting malaria microscopy training courses and annual malaria cases in Iran. Conducting a suitable programme for malaria microscopy training and refresher training plays an important role in the control of malaria in endemic areas. Obviously, the decrease of malaria cases in Iran has been achieved due to some activities that malaria diagnosis training was one of them.
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Controlling imported malaria cases in the United States of America.
Dembele, Bassidy; Yakubu, Abdul-Aziz
2017-02-01
We extend the mathematical malaria epidemic model framework of Dembele et al. and use it to ``capture" the 2013 Centers for Disease Control and Prevention (CDC) reported data on the 2011 number of imported malaria cases in the USA. Furthermore, we use our ``fitted" malaria models for the top 20 countries of malaria acquisition by USA residents to study the impact of protecting USA residents from malaria infection when they travel to malaria endemic areas, the impact of protecting residents of malaria endemic regions from mosquito bites and the impact of killing mosquitoes in those endemic areas on the CDC number of imported malaria cases in USA. To significantly reduce the number of imported malaria cases in USA, for each top 20 country of malaria acquisition by USA travelers, we compute the optimal proportion of USA international travelers that must be protected against malaria infection and the optimal proportion of mosquitoes that must be killed.
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Current Status of Malaria and Potential for Control
Phillips, R. S.
2001-01-01
Malaria remains one of the world's worst health problems with 1.5 to 2.7 million deaths annually; these deaths are primarily among children under 5 years of age and pregnant women in sub-Saharan Africa. Of significance, more people are dying from malaria today than 30 years ago. This review considers the factors which have contributed to this gloomy picture, including those which relate to the vector, the female anopheline mosquito; to human activity such as creating new mosquito breeding sites, the impact of increased numbers of people, and how their migratory behavior can increase the incidence and spread of malaria; and the problems of drug resistance by the parasites to almost all currently available antimalarial drugs. In a selective manner, this review describes what is being done to ameliorate this situation both in terms of applying existing methods in a useful or even crucial role in control and prevention and in terms of new additions to the antimalarial armory that are being developed. Topics covered include biological control of mosquitoes, the use of insecticide-impregnated bed nets, transgenic mosquitoes manipulated for resistance to malaria parasites, old and new antimalarial drugs, drug resistance and how best to maintain the useful life of antimalarials, immunity to malaria and the search for antimalarial vaccines, and the malaria genome project and the potential benefits to accrue from it. PMID:11148010
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Challenges and prospects for dengue and malaria control in Thailand, Southeast Asia.
Corbel, Vincent; Nosten, Francois; Thanispong, Kanutcharee; Luxemburger, Christine; Kongmee, Monthathip; Chareonviriyaphap, Theeraphap
2013-12-01
Despite significant advances in the search for potential dengue vaccines and new therapeutic schemes for malaria, the control of these diseases remains difficult. In Thailand, malaria incidence is falling whereas that of dengue is rising, with an increase in the proportion of reported severe cases. In the absence of antiviral therapeutic options for acute dengue, appropriate case management reduces mortality. However, the interruption of transmission still relies on vector control measures that are currently insufficient to curtail the cycle of epidemics. Drug resistance in malaria parasites is increasing, compromising malaria control and elimination. Deficiencies in our knowledge of vector biology and vectorial capacity also hinder public health efforts for vector control. Challenges to dengue and malaria control are discussed, and research priorities identified. Copyright © 2013. Published by Elsevier Ltd.
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Application of optimal control strategies to HIV-malaria co-infection dynamics
NASA Astrophysics Data System (ADS)
Fatmawati; Windarto; Hanif, Lathifah
2018-03-01
This paper presents a mathematical model of HIV and malaria co-infection transmission dynamics. Optimal control strategies such as malaria preventive, anti-malaria and antiretroviral (ARV) treatments are considered into the model to reduce the co-infection. First, we studied the existence and stability of equilibria of the presented model without control variables. The model has four equilibria, namely the disease-free equilibrium, the HIV endemic equilibrium, the malaria endemic equilibrium, and the co-infection equilibrium. We also obtain two basic reproduction ratios corresponding to the diseases. It was found that the disease-free equilibrium is locally asymptotically stable whenever their respective basic reproduction numbers are less than one. We also conducted a sensitivity analysis to determine the dominant factor controlling the transmission. sic reproduction numbers are less than one. We also conducted a sensitivity analysis to determine the dominant factor controlling the transmission. Then, the optimal control theory for the model was derived analytically by using Pontryagin Maximum Principle. Numerical simulations of the optimal control strategies are also performed to illustrate the results. From the numerical results, we conclude that the best strategy is to combine the malaria prevention and ARV treatments in order to reduce malaria and HIV co-infection populations.
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Epidemiology and control of malaria in Colombia
Rodríguez, Julio Cesar Padilla; Uribe, Gilberto Álvarez; Araújo, Roberto Montoya; Narváez, Pablo Chaparro; Valencia, Sócrates Herrera
2016-01-01
Malaria is currently one of the most serious public health problems in Colombia with an endemic/epidemic transmission pattern that has maintained endemic levels and an average of 105,000 annual clinical cases being reported over the last five years. Plasmodium vivax accounts for approximately 70% of reported cases with the remainder attributed almost exclusively to Plasmodium falciparum. A limited number of severe and complicated cases have resulted in mortality, which is a downward trend that has been maintained over the last few years. More than 90% of the malaria cases in Colombia are confined to 70 municipalities (about 7% of the total municipalities of Colombia), with high predominance (85%) in rural areas. The purpose of this paper is to review the progress of malaria-eradication activities and control measures over the past century within the eco-epidemiologic context of malaria transmission together with official consolidated morbidity and mortality reports. This review may contribute to the formulation of new antimalarial strategies and policies intended to achieve malaria elimination/eradication in Colombia and in the region. PMID:21881765
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Evaluation of Commercial Agrochemicals as New Tools for Malaria Vector Control.
Hoppé, Mark; Hueter, Ottmar F; Bywater, Andy; Wege, Philip; Maienfisch, Peter
2016-10-01
Malaria is a vector-borne and life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. The vector control insecticide market represents a small fraction of the crop protection market and is estimated to be valued at up to $500 million at the active ingredient level. Insecticide resistance towards the current WHOPES-approved products urgently requires the development of new tools to protect communities against the transmission of malaria. The evaluation of commercial products for malaria vector control is a viable and cost effective strategy to identify new malaria vector control products. Several examples of such spin-offs from crop protection insecticides are already evidencing the success of this strategy, namely pirimiphos-methyl for indoor residual sprays and spinosad, diflubenzuron, novaluron, and pyriproxifen for mosquito larvae control, a supplementary technology for control of malaria vectors. In our study the adulticidal activities of 81 insecticides representing 23 insecticidal modes of action classes, 34 fungicides from 6 fungicidal mode of action classes and 15 herbicides from 2 herbicidal modes of action classes were tested in a newly developed screening system. WHOPES approved insecticides for malaria vector control consistently caused 80-100% mortality of adult Anopheles stephensi at application rates between 0.2 and 20 mg active ingradient (AI) litre -1 . Chlorfenapyr, fipronil, carbosulfan and endosulfan showed the expected good activity. Four new insecticides and three fungicides with promising activity against adult mosquitoes were identified, namely the insecticides acetamiprid, thiamethoxam, thiocyclam and metaflumizone and the fungicides diflumetorin, picoxystrobin, and fluazinam. Some of these compounds certainly deserve to be further evaluated for malaria vector control. This is the first report describing good activity of commercial fungicides against malaria
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Simplified Models of Vector Control Impact upon Malaria Transmission by Zoophagic Mosquitoes
Kiware, Samson S.; Chitnis, Nakul; Moore, Sarah J.; Devine, Gregor J.; Majambere, Silas; Merrill, Stephen; Killeen, Gerry F.
2012-01-01
Background High coverage of personal protection measures that kill mosquitoes dramatically reduce malaria transmission where vector populations depend upon human blood. However, most primary malaria vectors outside of sub-Saharan Africa can be classified as “very zoophagic,” meaning they feed occasionally (<10% of blood meals) upon humans, so personal protection interventions have negligible impact upon their survival. Methods and Findings We extended a published malaria transmission model to examine the relationship between transmission, control, and the baseline proportion of bloodmeals obtained from humans (human blood index). The lower limit of the human blood index enables derivation of simplified models for zoophagic vectors that (1) Rely on only three field-measurable parameters. (2) Predict immediate and delayed (with and without assuming reduced human infectivity, respectively) impacts of personal protection measures upon transmission. (3) Illustrate how appreciable indirect communal-level protection for non-users can be accrued through direct personal protection of users. (4) Suggest the coverage and efficacy thresholds required to attain epidemiological impact. The findings suggest that immediate, indirect, community-wide protection of users and non-users alike may linearly relate to the efficacy of a user’s direct personal protection, regardless of whether that is achieved by killing or repelling mosquitoes. High protective coverage and efficacy (≥80%) are important to achieve epidemiologically meaningful impact. Non-users are indirectly protected because the two most common species of human malaria are strict anthroponoses. Therefore, the small proportion of mosquitoes that are killed or diverted while attacking humans can represent a large proportion of those actually transmitting malaria. Conclusions Simplified models of malaria transmission by very zoophagic vectors may be used by control practitioners to predict intervention impact
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Malaria vector control: from past to future.
Raghavendra, Kamaraju; Barik, Tapan K; Reddy, B P Niranjan; Sharma, Poonam; Dash, Aditya P
2011-04-01
Malaria is one of the most common vector-borne diseases widespread in the tropical and subtropical regions. Despite considerable success of malaria control programs in the past, malaria still continues as a major public health problem in several countries. Vector control is an essential part for reducing malaria transmission and became less effective in recent years, due to many technical and administrative reasons, including poor or no adoption of alternative tools. Of the different strategies available for vector control, the most successful are indoor residual spraying and insecticide-treated nets (ITNs), including long-lasting ITNs and materials. Earlier DDT spray has shown spectacular success in decimating disease vectors but resulted in development of insecticide resistance, and to control the resistant mosquitoes, organophosphates, carbamates, and synthetic pyrethroids were introduced in indoor residual spraying with needed success but subsequently resulted in the development of widespread multiple insecticide resistance in vectors. Vector control in many countries still use insecticides in the absence of viable alternatives. Few developments for vector control, using ovitraps, space spray, biological control agents, etc., were encouraging when used in limited scale. Likewise, recent introduction of safer vector control agents, such as insect growth regulators, biocontrol agents, and natural plant products have yet to gain the needed scale of utility for vector control. Bacterial pesticides are promising and are effective in many countries. Environmental management has shown sufficient promise for vector control and disease management but still needs advocacy for inter-sectoral coordination and sometimes are very work-intensive. The more recent genetic manipulation and sterile insect techniques are under development and consideration for use in routine vector control and for these, standardized procedures and methods are available but need thorough
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[Investigation on knowledge of malaria prevention and control in residents of Suining County].
Tang, Yue-e
2014-08-01
To understand the status of knowledge of malaria prevention and control in residents of Suining County, so as to provide the reference for improving the implementation of malaria elimination. Nine villages in 3 townships (3 villages per township) were randomly selected as the study areas, and 200 residents aged above 15 years of each village were investigated with questionnaire for the knowledge of malaria prevention and control. The awareness rates of "malaria transmission way", main symptoms of malaria", "life-threatening of falciparum malaria", "how to treat malaria", and "how to prevent malaria" were 96.27%, 95.01%, 81.46%, 98.19% and 96.27%, respectively. There were no significant differences between the different genders and among the different areas (all P >0.05), but there were significant differences among different age groups (all P <0.05). The awareness of malaria prevention and control in residents of Suining County is relatively high, which means the health education is effective.
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Hershey, Christine L.; Bhattarai, Achuyt; Florey, Lia S.; McElroy, Peter D.; Nielsen, Carrie F.; Yé, Yazoume; Eckert, Erin; Franca-Koh, Ana Cláudia; Shargie, Estifanos; Komatsu, Ryuichi; Smithson, Paul; Thwing, Julie; Mihigo, Jules; Herrera, Samantha; Taylor, Cameron; Shah, Jui; Mouzin, Eric; Yoon, Steven S.; Salgado, S. René
2017-01-01
Abstract. As funding for malaria control increased considerably over the past 10 years resulting in the expanded coverage of malaria control interventions, so did the need to measure the impact of these investments on malaria morbidity and mortality. Members of the Roll Back Malaria (RBM) Partnership undertook impact evaluations of malaria control programs at a time when there was little guidance in terms of the process for conducting an impact evaluation of a national-level malaria control program. The President’s Malaria Initiative (PMI), as a member of the RBM Partnership, has provided financial and technical support for impact evaluations in 13 countries to date. On the basis of these experiences, PMI and its partners have developed a streamlined process for conducting the evaluations with a set of lessons learned and recommendations. Chief among these are: to ensure country ownership and involvement in the evaluations; to engage stakeholders throughout the process; to coordinate evaluations among interested partners to avoid duplication of efforts; to tailor the evaluation to the particular country context; to develop a standard methodology for the evaluations and a streamlined process for completion within a reasonable time; and to develop tailored dissemination products on the evaluation for a broad range of stakeholders. These key lessons learned and resulting recommendations will guide future impact evaluations of malaria control programs and other health programs. PMID:28990921
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The Anopheles gambiae transcriptome - a turning point for malaria control.
Domingos, A; Pinheiro-Silva, R; Couto, J; do Rosário, V; de la Fuente, J
2017-04-01
Mosquitoes are important vectors of several pathogens and thereby contribute to the spread of diseases, with social, economic and public health impacts. Amongst the approximately 450 species of Anopheles, about 60 are recognized as vectors of human malaria, the most important parasitic disease. In Africa, Anopheles gambiae is the main malaria vector mosquito. Current malaria control strategies are largely focused on drugs and vector control measures such as insecticides and bed-nets. Improvement of current, and the development of new, mosquito-targeted malaria control methods rely on a better understanding of mosquito vector biology. An organism's transcriptome is a reflection of its physiological state and transcriptomic analyses of different conditions that are relevant to mosquito vector competence can therefore yield important information. Transcriptomic analyses have contributed significant information on processes such as blood-feeding parasite-vector interaction, insecticide resistance, and tissue- and stage-specific gene regulation, thereby facilitating the path towards the development of new malaria control methods. Here, we discuss the main applications of transcriptomic analyses in An. gambiae that have led to a better understanding of mosquito vector competence. © 2017 The Royal Entomological Society.
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Baiden, F; Malm, K; Bart-Plange, C; Hodgson, A; Chandramohan, D; Webster, J; Owusu-Agyei, S
2014-06-01
The presumptive approach was the World Health Organisation (WHO) recommended to the management of malaria for many years and this was incorporated into syndromic guidelines such as the Integrated Management of Childhood Illnesses (IMCI). In early 2010 however, WHO issued revised treatment guidelines that call for a shift from the presumptive to the test-based approach. Practically, this implies that in all suspected cases, the diagnosis of uncomplicated malaria should be confirmed using rapid test before treatment is initiated. This revision effectively brings to an end an era of clinical practice that span several years. Its implementation has important implications for the health systems in malaria-endemic countries. On the basis of research in Ghana and other countries, and evidence from program work, the Ghana National Malaria Control Program has issued revised national treatment guidelines that call for implementation of test-based management of malaria in all cases, and across all age groups. This article reviews the evidence and the technical basis for the shift to test-based management and examines the implications for malaria control in Ghana.
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Optimal control analysis of malaria-schistosomiasis co-infection dynamics.
Okosun, Kazeem Oare; Smith, Robert
2017-04-01
This paper presents a mathematical model for malaria--schistosomiasis co-infection in order to investigate their synergistic relationship in the presence of treatment. We first analyse the single infection steady states, then investigate the existence and stability of equilibria and then calculate the basic reproduction numbers. Both the single-infection models and the co-infection model exhibit backward bifurcations. We carrying out a sensitivity analysis of the co-infection model and show that schistosomiasis infection may not be associated with an increased risk of malaria. Conversely, malaria infection may be associated with an increased risk of schistosomiasis. Furthermore, we found that effective treatment and prevention of schistosomiasis infection would also assist in the effective control and eradication of malaria. Finally, we apply Pontryagin's Maximum Principle to the model in order to determine optimal strategies for control of both diseases.
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[Plan to improve malaria control towards its elimination in Mesoamerica].
Rodríguez, Mario Henry; Betanzos-Reyes, Angel Francisco
2011-01-01
To develop a plan to strengthen the control of malaria towards its elimination. In 2009, under the coordination of the National Public HealthInstitute ofMexico, atransdisciplinary equipment of technical and operative experts was conformed to carry out a situational analysis of malaria and control programs and for the selection of effective practices of intervention that would be incorporated to the plan, within the framework of an exercise in Theory of Change. Criteria for thestratificationof thelocalities, based ontheirtransmission characteristics were established. The structural and operative limitations of the control programs were identified. A plan of interventions was elaborated to improve the coverage of epidemiological surveillance, anti-malaria interventions and opportune diagnosis and treatment of cases. The plan delineates progressive phases of implementation: reorganization, intensification of interventions and evaluation of elimination feasibility. The adoption of a regional strategic plan will provide guidance and administrative elements to conform a system that coordinates the activities of the national control programs and facilitate the elimination of malaria in the region.
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Controlling Malaria Using Livestock-Based Interventions: A One Health Approach
Franco, Ana O.; Gomes, M. Gabriela M.; Rowland, Mark; Coleman, Paul G.
2014-01-01
Where malaria is transmitted by zoophilic vectors, two types of malaria control strategies have been proposed based on animals: using livestock to divert vector biting from people (zooprophylaxis) or as baits to attract vectors to insecticide sources (insecticide-treated livestock). Opposing findings have been obtained on malaria zooprophylaxis, and despite the success of an insecticide-treated livestock trial in Pakistan, where malaria vectors are highly zoophilic, its effectiveness is yet to be formally tested in Africa where vectors are more anthropophilic. This study aims to clarify the different effects of livestock on malaria and to understand under what circumstances livestock-based interventions could play a role in malaria control programmes. This was explored by developing a mathematical model and combining it with data from Pakistan and Ethiopia. Consistent with previous work, a zooprophylactic effect of untreated livestock is predicted in two situations: if vector population density does not increase with livestock introduction, or if livestock numbers and availability to vectors are sufficiently high such that the increase in vector density is counteracted by the diversion of bites from humans to animals. Although, as expected, insecticide-treatment of livestock is predicted to be more beneficial in settings with highly zoophilic vectors, like South Asia, we find that the intervention could also considerably decrease malaria transmission in regions with more anthropophilic vectors, like Anopheles arabiensis in Africa, under specific circumstances: high treatment coverage of the livestock population, using a product with stronger or longer lasting insecticidal effect than in the Pakistan trial, and with small (ideally null) repellency effect, or if increasing the attractiveness of treated livestock to malaria vectors. The results suggest these are the most appropriate conditions for field testing insecticide-treated livestock in an Africa region with
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Control of malaria: a successful experience from Viet Nam.
Hung, Le Q.; Vries, Peter J. de; Giao, Phan T.; Nam, Nguyen V.; Binh, Tran Q.; Chong, M. T.; Quoc, N. T. T. A.; Thanh, T. N.; Hung, L. N.; Kager, P. A.
2002-01-01
OBJECTIVE: To follow malaria prospectively in an ethnic minority commune in the south of Viet Nam with high malaria transmission and seasonal fluctuation, during malaria control interventions using insecticide-treated bednets (ITBNs) and early diagnosis and treatment (EDT) of symptomatic patients. METHODS: From 1994 onwards the following interventions were used: distribution of ITBNs to all households with biannual reimpregnation; construction of a health post and appointment of staff trained in microscopic diagnosis and treatment of malaria; regular supply of materials and drugs; annual cross-sectional malaria surveys with treatment of all parasitaemic subjects, and a programme of community involvement and health education. Surveys were held yearly at the end of the rainy season. During the surveys, demographic data were updated. Diagnosis and treatment of malaria were free of charge. Plasmodium falciparum infection was treated with artesunate and P. vivax infection with chloroquine plus primaquine. FINDINGS: The baseline survey in 1994 recorded 716 inhabitants. Of the children under 2 years of age, 37% were parasitaemic; 56% of children aged 2-10 years, and 35% of the remaining population were parasitaemic. P. falciparum accounted for 73-79% of these infections. The respective splenomegaly rates for the above-mentioned age groups were 20%, 56%, and 32%. In 1999, the proportion of parasitaemic subjects was 4%, 7% and 1%, respectively, of which P.falciparum contributed 56%. The splenomegaly rate was 0%, 5% and 2%, respectively. CONCLUSIONS: A combination of ITBNs and EDT, provided free of charge, complemented by annual diagnosis and treatment during malaria surveys and community involvement with health education successfully brought malaria under control. This approach could be applied to other regions in the south of Viet Nam and provides a sound basis for further studies in other areas with different epidemiological patterns of malaria. PMID:12219158
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Urbanization and the global malaria recession
2013-01-01
Background The past century has seen a significant contraction in the global extent of malaria transmission, resulting in over 50 countries being declared malaria free, and many regions of currently endemic countries eliminating the disease. Moreover, substantial reductions in transmission have been seen since 1900 in those areas that remain endemic today. Recent work showed that this malaria recession was unlikely to have been driven by climatic factors, and that control measures likely played a significant role. It has long been considered, however, that economic development, and particularly urbanization, has also been a causal factor. The urbanization process results in profound socio-economic and landscape changes that reduce malaria transmission, but the magnitude and extent of these effects on global endemicity reductions are poorly understood. Methods Global data at subnational spatial resolution on changes in malaria transmission intensity and urbanization trends over the past century were combined to examine the relationships seen over a range of spatial and temporal scales. Results/Conclusions A consistent pattern of increased urbanization coincident with decreasing malaria transmission and elimination over the past century was found. Whilst it remains challenging to untangle whether this increased urbanization resulted in decreased transmission, or that malaria reductions promoted development, the results point to a close relationship between the two, irrespective of national wealth. The continuing rapid urbanization in malaria-endemic regions suggests that such malaria declines are likely to continue, particularly catalyzed by increasing levels of direct malaria control. PMID:23594701
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Cost of malaria control in Sri Lanka.
Konradsen, F; Steele, P; Perera, D; van der Hoek, W; Amerasinghe, P H; Amerasinghe, F P
1999-01-01
The study provides estimates of the cost of various malaria control measures in an area of North-Central Province of Sri Lanka where the disease is endemic. We assumed that each measure was equally effective. In these terms, impregnating privately purchased bednets with insecticide was estimated to cost Rs 48 (US(40.87) per individual protected per year, less than half the cost of spraying houses with residual insecticides. Larviciding of vector breeding sites and especially the elimination of breeding habitats by flushing streams through seasonal release of water from upstream reservoirs was estimated to be cheaper than other preventive measures (Rs 27 (US$ 0.49) and Rs 13 (US$ 0.24) per individual protected, respectively). Inclusion of both operational and capital costs of treatment indicates that the most cost-effective intervention for the government was a centrally located hospital with a relatively large catchment area (Rs 71 (US$ 1.29) per malaria case treated). Mobile clinics (Rs 153 (US$ 2.78) per malaria case treated) and a village treatment centre (Rs 112 (US$ 2.04)) per malaria case treated) were more expensive options for the government, but were considerably cheaper for households than the traditional hospital facilities. This information can guide health planners and government decision-makers in choosing the most appropriate combination of curative and preventive measures to control malaria. However, the option that is cheapest for the government may not be so for the householders, and further studies are needed to estimate the effectiveness of the various preventive measures.
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Cost of malaria control in Sri Lanka.
Konradsen, F.; Steele, P.; Perera, D.; van der Hoek, W.; Amerasinghe, P. H.; Amerasinghe, F. P.
1999-01-01
The study provides estimates of the cost of various malaria control measures in an area of North-Central Province of Sri Lanka where the disease is endemic. We assumed that each measure was equally effective. In these terms, impregnating privately purchased bednets with insecticide was estimated to cost Rs 48 (US(40.87) per individual protected per year, less than half the cost of spraying houses with residual insecticides. Larviciding of vector breeding sites and especially the elimination of breeding habitats by flushing streams through seasonal release of water from upstream reservoirs was estimated to be cheaper than other preventive measures (Rs 27 (US$ 0.49) and Rs 13 (US$ 0.24) per individual protected, respectively). Inclusion of both operational and capital costs of treatment indicates that the most cost-effective intervention for the government was a centrally located hospital with a relatively large catchment area (Rs 71 (US$ 1.29) per malaria case treated). Mobile clinics (Rs 153 (US$ 2.78) per malaria case treated) and a village treatment centre (Rs 112 (US$ 2.04)) per malaria case treated) were more expensive options for the government, but were considerably cheaper for households than the traditional hospital facilities. This information can guide health planners and government decision-makers in choosing the most appropriate combination of curative and preventive measures to control malaria. However, the option that is cheapest for the government may not be so for the householders, and further studies are needed to estimate the effectiveness of the various preventive measures. PMID:10327708
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Impact of pyrethroid resistance on operational malaria control in Malawi
Wondji, Charles S.; Coleman, Michael; Kleinschmidt, Immo; Mzilahowa, Themba; Irving, Helen; Ndula, Miranda; Rehman, Andrea; Morgan, John; Barnes, Kayla G.; Hemingway, Janet
2012-01-01
The impact of insecticide resistance on insect-borne disease programs is difficult to quantify. The possibility of eliminating malaria in high-transmission settings is heavily dependent on effective vector control reducing disease transmission rates. Pyrethroids are the dominant insecticides used for malaria control, with few options for their replacement. Their failure will adversely affect our ability to control malaria. Pyrethroid resistance has been selected in Malawi over the last 3 y in the two major malaria vectors Anopheles gambiae and Anopheles funestus, with a higher frequency of resistance in the latter. The resistance in An. funestus is metabolically based and involves the up-regulation of two duplicated P450s. The same genes confer resistance in Mozambican An. funestus, although the levels of up-regulation differ. The selection of resistance over 3 y has not increased malaria transmission, as judged by annual point prevalence surveys in 1- to 4-y-old children. This is true in areas with long-lasting insecticide-treated nets (LLINs) alone or LLINs plus pyrethroid-based insecticide residual spraying (IRS). However, in districts where IRS was scaled up, it did not produce the expected decrease in malaria prevalence. As resistance increases in frequency from this low initial level, there is the potential for vector population numbers to increase with a concomitant negative impact on control efficacy. This should be monitored carefully as part of the operational activities in country. PMID:23118337
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Basu, Sanjay
2002-01-01
Although malaria is a growing problem affecting several hundred million people each year, many malarial countries lack successful disease control programs. Worldwide malaria incidence rates are dramatically increasing, generating fear among many people who are witnessing malaria control initiatives fail. In this paper, we explore two options for malaria control in poor countries: (1) the production and distribution of a malaria vaccine and (2) the control of mosquitoes that harbor the malaria parasite. We first demonstrate that the development of a malaria vaccine is indeed likely, although it will take several years to produce because of both biological obstacles and insufficient research support. The distribution of such a vaccine, as suggested by some economists, will require that wealthy states promise a market to pharmaceutical companies who have traditionally failed to investigate diseases affecting the poorest of nations. But prior to the development of a malaria vaccine, we recommend the implementation of vector control pro- grams, such as those using Bti toxin, in regions with low vector capacity. Our analysis indicates that both endogenous programs in malarial regions and molecular approaches to parasite control will provide pragmatic solutions to the malaria problem. But the successful control of malaria will require sustained support from wealthy nations, without whom vaccine development and vector control programs will likely fail.
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Jackson, Sukhan; Sleigh, Adrian C.; Liu, Xi-Li
2002-01-01
OBJECTIVE: To assist with strategic planning for the eradication of malaria in Henan Province, China, which reached the consolidation phase of malaria control in 1992, when only 318 malaria cases were reported. METHODS: We conducted a prospective two-year study of the costs for Henan's malaria control programme. We used a cost model that could also be applied to other malaria programmes in mainland China, and analysed the cost of the three components of Henan's malaria programme: suspected malaria case management, vector surveillance, and population blood surveys. Primary cost data were collected from the government, and data on suspected malaria patients were collected in two malaria counties (population 2 093 100). We enlisted the help of 260 village doctors in six townships or former communes (population 247 762), and studied all 12 325 reported cases of suspected malaria in their catchment areas in 1994 and 1995. FINDINGS: The average annual government investment in malaria control was estimated to be US$ 111 516 (case-management 59%; active blood surveys 25%; vector surveillance 12%; and contingencies and special projects 4%). The average cost (direct and indirect) for patients seeking treatment for suspected malaria was US$ 3.48, equivalent to 10 days' income for rural residents. Each suspected malaria case cost the government an average of US$ 0.78. CONCLUSION: Further cuts in government funding will increase future costs when epidemic malaria returns; investment in malaria control should therefore continue at least at current levels of US$ 0.03 per person at risk. PMID:12219157
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Lessons from malaria control to help meet the rising challenge of dengue.
Anders, Katherine L; Hay, Simon I
2012-12-01
Achievements in malaria control could inform efforts to control the increasing global burden of dengue. Better methods for quantifying dengue endemicity-equivalent to parasite prevalence surveys and endemicity mapping used for malaria-would help target resources, monitor progress, and advocate for investment in dengue prevention. Success in controlling malaria has been attributed to widespread implementation of interventions with proven efficacy. An improved evidence base is needed for large-scale delivery of existing and novel interventions for vector control, alongside continued investment in dengue drug and vaccine development. Control of dengue is unlikely to be achieved without coordinated international financial and technical support for national programmes, which has proven effective in reducing the global burden of malaria. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Tsoka-Gwegweni, J M; Kleinschmidt, I
2013-01-24
South Africa has no policy to prevent malaria in pregnancy, despite the adverse effects of the disease in pregnancy. However, malaria control measures consisting of indoor residual spraying and specific antimalarial treatment have been in place since the 1970s. Information on the burden of malaria in pregnancy in South Africa is needed to indicate whether a specific policy for malaria prevention in pregnancy is necessary. To determine the burden of malaria in pregnancy in KwaZulu-Natal (KZN) province, South Africa. Pregnant women were enrolled at their first antenatal care visit to three health facilities in Umkhanyakude health district in northern KZN during May 2004 - September 2005 and followed up until delivery. Data collection included demographic details, current and previous malaria infection during pregnancy, haemoglobin concentrations and birth outcomes. Of the 1 406 study participants, more than a quarter were younger than 20 years of age, and more than 90% were unemployed and unmarried. Although 33.2% of the women were anaemic, this was not related to malaria. The prevalence and incidence of malaria were very low, and low birth weight was only weakly associated with malaria (1/10). The low burden of malaria in these pregnant women suggests that they have benefited from malaria control strategies in the study area. The implication is that additional measures specific for malaria prevention in pregnancy are not required. However, ongoing monitoring is needed to ensure that malaria prevalence remains low.
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Optimal strategy for controlling the spread of Plasmodium Knowlesi malaria: Treatment and culling
NASA Astrophysics Data System (ADS)
Abdullahi, Mohammed Baba; Hasan, Yahya Abu; Abdullah, Farah Aini
2015-05-01
Plasmodium Knowlesi malaria is a parasitic mosquito-borne disease caused by a eukaryotic protist of genus Plasmodium Knowlesi transmitted by mosquito, Anopheles leucosphyrus to human and macaques. We developed and analyzed a deterministic Mathematical model for the transmission of Plasmodium Knowlesi malaria in human and macaques. The optimal control theory is applied to investigate optimal strategies for controlling the spread of Plasmodium Knowlesi malaria using treatment and culling as control strategies. The conditions for optimal control of the Plasmodium Knowlesi malaria are derived using Pontryagin's Maximum Principle. Finally, numerical simulations suggested that the combination of the control strategies is the best way to control the disease in any community.
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Peeters Grietens, Koen; Xuan, Xa Nguyen; Van Bortel, Wim; Duc, Thang Ngo; Ribera, Joan Muela; Ba Nhat, Truong; Van, Ky Pham; Le Xuan, Hung; D'Alessandro, Umberto; Erhart, Annette
2010-01-20
Despite Vietnam's success in reducing malaria mortality and morbidity over the last decade, malaria persists in the forested and mountainous areas of the central and southern provinces, where more than 50% of the clinical cases and 90% of severe cases and malaria deaths occur. Between July 2005 and September 2006, a multi-method study, triangulating a malariometric cross-sectional survey and qualitative data from focused ethnography, was carried out among the Ra-glai ethnic minority in the hilly forested areas of south-central Vietnam. Despite the relatively high malaria burden among the Ra-glai and their general awareness that mosquitoes can transmit an unspecific kind of fever (84.2%), the use of bed nets, distributed free of charge by the national malaria control programme, remains low at the farmers' forest fields where the malaria risk is the highest. However, to meet work requirements during the labour intensive malaria transmission and rainy season, Ra-glai farmers combine living in government supported villages along the road with a second home or shelter at their slash and burn fields located in the forest. Bed net use was 84.6% in the villages but only 52.9% at the forest fields; 20.6% of the respondents slept unprotected in both places. Such low use may be explained by the low perception of the risk for malaria, decreasing the perceived need to sleep protected. Several reasons may account for this: (1) only 15.6% acknowledged the higher risk of contracting malaria in the forest than in the village; (2) perceived mosquito biting times only partially coincided with Anopheles dirus ss and Anopheles minimus A true biting times; (3) the disease locally identified as 'malaria' was hardly perceived as having an impact on forest farmers' daily lives as they were unaware of the specific kind of fevers from which they had suffered even after being diagnosed with malaria at the health centre (20.9%). The progressive confinement of malaria to minority groups and
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Abeyasinghe, Rabindra R.; Galappaththy, Gawrie N. L.; Smith Gueye, Cara; Kahn, James G.; Feachem, Richard G. A.
2012-01-01
Background Sri Lanka has a long history of malaria control, and over the past decade has had dramatic declines in cases amid a national conflict. A case study of Sri Lanka's malaria programme was conducted to characterize the programme and explain recent progress. Methods The case study employed qualitative and quantitative methods. Data were collected from published and grey literature, district-level and national records, and thirty-three key informant interviews. Expenditures in two districts for two years – 2004 and 2009 – were compiled. Findings Malaria incidence in Sri Lanka has declined by 99.9% since 1999. During this time, there were increases in the proportion of malaria infections due to Plasmodium vivax, and the proportion of infections occurring in adult males. Indoor residual spraying and distribution of long-lasting insecticide-treated nets have likely contributed to the low transmission. Entomological surveillance was maintained. A strong passive case detection system captures infections and active case detection was introduced. When comparing conflict and non-conflict districts, vector control and surveillance measures were maintained in conflict areas, often with higher coverage reported in conflict districts. One of two districts in the study reported a 48% decline in malaria programme expenditure per person at risk from 2004 to 2009. The other district had stable malaria spending. Conclusions/Significance Malaria is now at low levels in Sri Lanka – 124 indigenous cases were found in 2011. The majority of infections occur in adult males and are due to P. vivax. Evidence-driven policy and an ability to adapt to new circumstances contributed to this decline. Malaria interventions were maintained in the conflict districts despite an ongoing war. Sri Lanka has set a goal of eliminating malaria by the end of 2014. Early identification and treatment of infections, especially imported ones, together with effective surveillance and response, will
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Using a geographical information system to plan a malaria control programme in South Africa.
Booman, M.; Durrheim, D. N.; La Grange, K.; Martin, C.; Mabuza, A. M.; Zitha, A.; Mbokazi, F. M.; Fraser, C.; Sharp, B. L.
2000-01-01
INTRODUCTION: Sustainable control of malaria in sub-Saharan Africa is jeopardized by dwindling public health resources resulting from competing health priorities that include an overwhelming acquired immunodeficiency syndrome (AIDS) epidemic. In Mpumalanga province, South Africa, rational planning has historically been hampered by a case surveillance system for malaria that only provided estimates of risk at the magisterial district level (a subdivision of a province). METHODS: To better map control programme activities to their geographical location, the malaria notification system was overhauled and a geographical information system implemented. The introduction of a simplified notification form used only for malaria and a carefully monitored notification system provided the good quality data necessary to support an effective geographical information system. RESULTS: The geographical information system displays data on malaria cases at a village or town level and has proved valuable in stratifying malaria risk within those magisterial districts at highest risk, Barberton and Nkomazi. The conspicuous west-to-east gradient, in which the risk rises sharply towards the Mozambican border (relative risk = 4.12, 95% confidence interval = 3.88-4.46 when the malaria risk within 5 km of the border was compared with the remaining areas in these two districts), allowed development of a targeted approach to control. DISCUSSION: The geographical information system for malaria was enormously valuable in enabling malaria risk at town and village level to be shown. Matching malaria control measures to specific strata of endemic malaria has provided the opportunity for more efficient malaria control in Mpumalanga province. PMID:11196490
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Akhavan, D; Musgrove, P; Abrantes, A; d'A Gusmão, R
1999-11-01
Malaria transmission was controlled elsewhere in Brazil by 1980, but in the Amazon Basin cases increased steadily until 1989, to almost half a million a year and the coefficient of mortality quadrupled in 1977-1988. The government's malaria control program almost collapsed financially in 1987-1989 and underwent a turbulent reorganization in 1991-1993. A World Bank project supported the program from late 1989 to mid-1996, and in 1992-1993, with help from the Pan American Health Organization, facilitated a change toward earlier and more aggressive case treatment and more concentrated vector control. The epidemic stopped expanding in 1990-1991 and reversed in 1992-1996. The total cost of the program from 1989 through mid-1996 was US$616 million: US$526 million for prevention and US$90 million for treatment. Compared to what would have happened in the absence of the program, nearly two million cases of malaria and 231,000 deaths were prevented; the lives saved were due almost equally to preventing infection and to case treatment. Converting the savings in lives and in morbidity into Disability-Adjusted Life Years yields almost nine million DALYs, 5.1 million from treatment and 3.9 million from prevention. Nearly all the gain came from controlling deaths and therefore from controlling falciparum. The overall cost-effectiveness was US$2672 per life saved or US$69 per DALY, which is low compared to most previous estimates and compares favorably to many other disease control interventions. Contrary to much previous experience, case treatment appears more cost-effective than vector control, particularly where falciparum is prevalent and unfocussed insecticide spraying is relatively ineffective. Halting the epidemic by better targeted vector control and emphasizing treatment paid off in much reduced mortality from malaria and in significantly lower costs per life saved.
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Yeka, Adoke; Gasasira, Anne; Mpimbaza, Arthur; Achan, Jane; Nankabirwa, Joaniter; Nsobya, Sam; Staedke, Sarah G.; Donnelly, Martin J.; Wabwire-Mangen, Fred; Talisuna, Ambrose; Dorsey, Grant; Kamya, Moses R.; Rosenthal, Philip J.
2012-01-01
In the recent past there have been several reports of successes in malaria control, leading some public health experts to conclude that Africa is witnessing an epidemiological transition, from an era of failed malaria control to progression from successful control to elimination. Successes in control have been attributed to increased international donor support leading to increased intervention coverage. However, these changes are not uniform across Africa. In Uganda, where baseline transmission is very high and intervention coverage not yet to scale, the malaria burden is not declining and has even likely increased in the last decade. In this article we present perspectives for the future for Uganda and other malaria endemic countries with high baseline transmission intensity and significant health system challenges. For these high burden areas,malaria elimination is currently not feasible, and early elimination programs are inappropriate, as they would further fragment already fragmented and inefficient malaria control systems. Rather, health impacts will be maximized by aiming to achieve universal coverage of proven interventions in the context of a strengthened health system. PMID:21756863
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Control of Plasmodium knowlesi malaria
NASA Astrophysics Data System (ADS)
Abdullahi, Mohammed Baba; Hasan, Yahya Abu; Abdullah, Farah Aini
2015-10-01
The most significant and efficient measures against Plasmodium knowlesi outbreaks are efficient anti malaria drug, biological control in form of predatory mosquitoes and culling control strategies. In this paper optimal control theory is applied to a system of ordinary differential equation. It describes the disease transmission and Pontryagin's Maximum Principle is applied for analysis of the control. To this end, three control strategies representing biological control, culling and treatment were incorporated into the disease transmission model. The simulation results show that the implementation of the combination strategy during the epidemic is the most cost-effective strategy for disease transmission.
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2013-01-01
Background Malaria remains the leading communicable disease in Ethiopia, with around one million clinical cases of malaria reported annually. The country currently has plans for elimination for specific geographic areas of the country. Human movement may lead to the maintenance of reservoirs of infection, complicating attempts to eliminate malaria. Methods An unmatched case–control study was conducted with 560 adult patients at a Health Centre in central Ethiopia. Patients who received a malaria test were interviewed regarding their recent travel histories. Bivariate and multivariate analyses were conducted to determine if reported travel outside of the home village within the last month was related to malaria infection status. Results After adjusting for several known confounding factors, travel away from the home village in the last 30 days was a statistically significant risk factor for infection with Plasmodium falciparum (AOR 1.76; p=0.03) but not for infection with Plasmodium vivax (AOR 1.17; p=0.62). Male sex was strongly associated with any malaria infection (AOR 2.00; p=0.001). Conclusions Given the importance of identifying reservoir infections, consideration of human movement patterns should factor into decisions regarding elimination and disease prevention, especially when targeted areas are limited to regions within a country. PMID:23347703
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Hiscox, Alexandra; Homan, Tobias; Mweresa, Collins K; Maire, Nicolas; Di Pasquale, Aurelio; Masiga, Daniel; Oria, Prisca A; Alaii, Jane; Leeuwis, Cees; Mukabana, Wolfgang R; Takken, Willem; Smith, Thomas A
2016-07-26
Increasing levels of insecticide resistance as well as outdoor, residual transmission of malaria threaten the efficacy of existing vector control tools used against malaria mosquitoes. The development of odour-baited mosquito traps has led to the possibility of controlling malaria through mass trapping of malaria vectors. Through daily removal trapping against a background of continued bed net use it is anticipated that vector populations could be suppressed to a level where continued transmission of malaria will no longer be possible. A stepped wedge cluster-randomised trial design was used for the implementation of mass mosquito trapping on Rusinga Island, western Kenya (the SolarMal project). Over the course of 2 years (2013-2015) all households on the island were provided with a solar-powered mosquito trapping system. A continuous health and demographic surveillance system combined with parasitological surveys three times a year, successive rounds of mosquito monitoring and regular sociological studies allowed measurement of intervention outcomes before, during and at completion of the rollout of traps. Data collection continued after achieving mass coverage with traps in order to estimate the longer term effectiveness of this novel intervention. Solar energy was exploited to provide electric light and mobile phone charging for each household, and the impacts of these immediate tangible benefits upon acceptability of and adherence to the use of the intervention are being measured. This study will be the first to evaluate whether the principle of solar-powered mass mosquito trapping could be an effective tool for elimination of malaria. If proven to be effective, this novel approach to malaria control would be a valuable addition to the existing strategies of long-lasting insecticide-treated nets and case management. Sociological studies provide a knowledge base for understanding the usage of this novel tool. Trialregister.nl: NTR3496 - SolarMal. Registered on
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Malaria resurgence: a systematic review and assessment of its causes
2012-01-01
Background Considerable declines in malaria have accompanied increased funding for control since the year 2000, but historical failures to maintain gains against the disease underscore the fragility of these successes. Although malaria transmission can be suppressed by effective control measures, in the absence of active intervention malaria will return to an intrinsic equilibrium determined by factors related to ecology, efficiency of mosquito vectors, and socioeconomic characteristics. Understanding where and why resurgence has occurred historically can help current and future malaria control programmes avoid the mistakes of the past. Methods A systematic review of the literature was conducted to identify historical malaria resurgence events. All suggested causes of these events were categorized according to whether they were related to weakened malaria control programmes, increased potential for malaria transmission, or technical obstacles like resistance. Results The review identified 75 resurgence events in 61 countries, occurring from the 1930s through the 2000s. Almost all resurgence events (68/75 = 91%) were attributed at least in part to the weakening of malaria control programmes for a variety of reasons, of which resource constraints were the most common (39/68 = 57%). Over half of the events (44/75 = 59%) were attributed in part to increases in the intrinsic potential for malaria transmission, while only 24/75 (32%) were attributed to vector or drug resistance. Conclusions Given that most malaria resurgences have been linked to weakening of control programmes, there is an urgent need to develop practical solutions to the financial and operational threats to effectively sustaining today’s successful malaria control programmes. PMID:22531245
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2013-01-01
Background Malaria transmission is highly heterogeneous in most settings, resulting in the formation of recognizable malaria hotspots. Targeting these hotspots might represent a highly efficacious way of controlling or eliminating malaria if the hotspots fuel malaria transmission to the wider community. Methods/design Hotspots of malaria will be determined based on spatial patterns in age-adjusted prevalence and density of antibodies against malaria antigens apical membrane antigen-1 and merozoite surface protein-1. The community effect of interventions targeted at these hotspots will be determined. The intervention will comprise larviciding, focal screening and treatment of the human population, distribution of long-lasting insecticide-treated nets and indoor residual spraying. The impact of the intervention will be determined inside and up to 500 m outside the targeted hotspots by PCR-based parasite prevalence in cross-sectional surveys, malaria morbidity by passive case detection in selected facilities and entomological monitoring of larval and adult Anopheles populations. Discussion This study aims to provide direct evidence for a community effect of hotspot-targeted interventions. The trial is powered to detect large effects on malaria transmission in the context of ongoing malaria interventions. Follow-up studies will be needed to determine the effect of individual components of the interventions and the cost-effectiveness of a hotspot-targeted approach, where savings made by reducing the number of compounds that need to receive interventions should outweigh the costs of hotspot-detection. Trial registration NCT01575613. The protocol was registered online on 20 March 2012; the first community was randomized on 26 March 2012. PMID:23374910
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2014-01-01
Background Identifying human and malaria parasite movements is important for control planning across all transmission intensities. Imported infections can reintroduce infections into areas previously free of infection, maintain ‘hotspots’ of transmission and import drug resistant strains, challenging national control programmes at a variety of temporal and spatial scales. Recent analyses based on mobile phone usage data have provided valuable insights into population and likely parasite movements within countries, but these data are restricted to sub-national analyses, leaving important cross-border movements neglected. Methods National census data were used to analyse and model cross-border migration and movement, using East Africa as an example. ‘Hotspots’ of origin-specific immigrants from neighbouring countries were identified for Kenya, Tanzania and Uganda. Populations of origin-specific migrants were compared to distance from origin country borders and population size at destination, and regression models were developed to quantify and compare differences in migration patterns. Migration data were then combined with existing spatially-referenced malaria data to compare the relative propensity for cross-border malaria movement in the region. Results The spatial patterns and processes for immigration were different between each origin and destination country pair. Hotspots of immigration, for example, were concentrated close to origin country borders for most immigrants to Tanzania, but for Kenya, a similar pattern was only seen for Tanzanian and Ugandan immigrants. Regression model fits also differed between specific migrant groups, with some migration patterns more dependent on population size at destination and distance travelled than others. With these differences between immigration patterns and processes, and heterogeneous transmission risk in East Africa and the surrounding region, propensities to import malaria infections also likely show
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Hardy, Andrew J.; Gamarra, Javier G. P.; Cross, Dónall E.; Macklin, Mark G.; Smith, Mark W.; Kihonda, Japhet; Killeen, Gerry F.; Ling’ala, George N.; Thomas, Chris J.
2013-01-01
Background Larval source management is a promising component of integrated malaria control and elimination. This requires development of a framework to target productive locations through process-based understanding of habitat hydrology and geomorphology. Methods We conducted the first catchment scale study of fine resolution spatial and temporal variation in Anopheles habitat and productivity in relation to rainfall, hydrology and geomorphology for a high malaria transmission area of Tanzania. Results Monthly aggregates of rainfall, river stage and water table were not significantly related to the abundance of vector larvae. However, these metrics showed strong explanatory power to predict mosquito larval abundances after stratification by water body type, with a clear seasonal trend for each, defined on the basis of its geomorphological setting and origin. Conclusion Hydrological and geomorphological processes governing the availability and productivity of Anopheles breeding habitat need to be understood at the local scale for which larval source management is implemented in order to effectively target larval source interventions. Mapping and monitoring these processes is a well-established practice providing a tractable way forward for developing important malaria management tools. PMID:24312606
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Developing an expanded vector control toolbox for malaria elimination
Tatarsky, Allison; Diabate, Abdoulaye; Chaccour, Carlos J; Marshall, John M; Okumu, Fredros O; Brunner, Shannon; Newby, Gretchen; Williams, Yasmin A; Malone, David; Tusting, Lucy S; Gosling, Roland D
2017-01-01
Vector control using long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) accounts for most of the malaria burden reductions achieved recently in low and middle-income countries (LMICs). LLINs and IRS are highly effective, but are insufficient to eliminate malaria transmission in many settings because of operational constraints, growing resistance to available insecticides and mosquitoes that behaviourally avoid contact with these interventions. However, a number of substantive opportunities now exist for rapidly developing and implementing more diverse, effective and sustainable malaria vector control strategies for LMICs. For example, mosquito control in high-income countries is predominantly achieved with a combination of mosquito-proofed housing and environmental management, supplemented with large-scale insecticide applications to larval habitats and outdoor spaces that kill off vector populations en masse, but all these interventions remain underused in LMICs. Programmatic development and evaluation of decentralised, locally managed systems for delivering these proactive mosquito population abatement practices in LMICs could therefore enable broader scale-up. Furthermore, a diverse range of emerging or repurposed technologies are becoming available for targeting mosquitoes when they enter houses, feed outdoors, attack livestock, feed on sugar or aggregate into mating swarms. Global policy must now be realigned to mobilise the political and financial support necessary to exploit these opportunities over the decade ahead, so that national malaria control and elimination programmes can access a much broader, more effective set of vector control interventions. PMID:28589022
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Discourse on malaria elimination: where do forcibly displaced persons fit in these discussions?
2013-01-01
Background Individuals forcibly displaced are some of the poorest people in the world, living in areas where infrastructure and services are at a bare minimum. Out of a total of 10,549,686 refugees protected and assisted by the United Nations High Commissioner for Refugees globally, 6,917,496 (65.6%) live in areas where malaria is transmitted. Historically, national malaria control programmes have excluded displaced populations. Results The current discourse on malaria elimination rarely includes discussion of forcibly displaced persons who reside within malaria-eliminating countries. Of the 100 malaria-endemic countries, 64 are controlling malaria and 36 are in some stage of elimination. Of these, 30 malaria-controlling countries and 13 countries in some phase of elimination host displaced populations of ≥50,000, even though 13 of the 36 (36.1%) malaria-elimination countries host displaced populations of ≥50,000 people. Discussion Now is the time for the malaria community to incorporate forcibly displaced populations residing within malarious areas into malaria control activities. Beneficiaries, whether they are internally displaced persons or refugees, should be viewed as partners in the delivery of malaria interventions and not simply as recipients. Conclusion Until equitable and sustainable malaria control includes everyone residing in an endemic area, the goal of malaria elimination will not be met. PMID:23575209
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Aggressive active case detection: a malaria control strategy based on the Brazilian model.
Macauley, Cameron
2005-02-01
Since 1996, the Brazilian Ministry of Health has adopted a malaria control strategy known as aggressive active case detection (AACD) in which most or all members of every community are tested and treated for malaria on a monthly basis. The strategy attempts to identify and treat cases of asymptomatic malaria, which, if untreated, continue to transmit the infection. Malaria remains uncontrolled because almost all health care systems in the world rely on passive case detection: the treatment of only symptomatic cases of malaria. Research has shown conclusively that asymptomatic cases exist in any population where malaria transmission is stable and incidence is high: therefore passive case detection simply will not succeed in breaking the cycle of transmission. Numerous case studies show that malaria has been successfully controlled on a regional or national level by mass blood surveys. AACD is an effective malaria control strategy if used in conjunction with other methods, especially when (1) an effective treatment exists, (2) influx of potential carriers of the infection can be monitored, and (3) people are inclined to cooperate with monthly blood testing. AACD requires access to rapid diagnostic tests (RDTs), microscopy supplies, extensive human resources, and prompt, affordable, and effective treatment. AACD is compared to PCD in terms of clinical efficacy and cost effectiveness in a case study of malaria in the Brazilian Yanomami Indians. Where it is feasible, AACD could drastically reduce the incidence of malaria and should be an integral part of the World Health Organization's Roll Back Malaria strategy.
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Factoring quality laboratory diagnosis into the malaria control agenda for sub-Saharan Africa.
Aidoo, Michael
2013-09-01
Recent progress in malaria control in sub-Saharan Africa has been achieved primarily through provision of insecticide-treated nets, indoor residual spraying, and antimalarial drugs. Although these interventions are important, proper case identification and accurate measurement of their impact depend on quality diagnostic testing. Current availability of diagnostic testing for malaria in sub-Saharan Africa is inadequate to support disease management, prevention programs, and surveillance needs. Challenges faced include a dearth of skilled workforce, inadequate health systems infrastructure, and lack of political will. A coordinated approach to providing pre-service clinical and laboratory training together with systems that support a scale-up of laboratory services could provide means not only for effective malaria case management but also, management of non-malaria febrile illnesses, disease surveillance, and accurate control program evaluation. A synthesis of the challenges faced in ensuring quality malaria testing and how to include this information in the malaria control and elimination agenda are presented.
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Nzobo, Baraka J; Ngasala, Billy E; Kihamia, Charles M
2015-12-02
Malaria is a public health problem in Tanzania affecting all age groups. It is known that school children are the age group most commonly infected with malaria parasites. Their infections are usually asymptomatic, go unnoticed and thus never get treated, result in anaemia, reduced ability to concentrate and learn in school and if fallen sick may lead to school absenteeism. Effective malaria control requires frequent evaluation of effectiveness of different malaria interventions. A cross-sectional study design involving 317 out of 350 school children aged 6-13 years from five primary schools within municipality was conducted. Multistage cluster sampling and simple random sampling methods were used to obtain primary school and study participants, respectively. Finger-prick blood samples were collected for Plasmodium parasite detection by malaria rapid diagnostic test (mRDT) and haemoglobin level assessment by Easy Touch(®) GHb system machine. A questionnaire was administered to assess use of insecticide-treated nets (ITNs) and anti-malarial drugs. The prevalence of asymptomatic malaria was 5.4 % (95 % CI 3.3-8.6 %) and anaemia was 10.1 % (95 % CI 7.2-13.9 %). School children aged 6-9 years were more affected by malaria than those aged 10-13 years. The proportion of ITNs used was 90.6 % (95 % CI 86.3-93.9 %) while that of artemisinin combination therapy (ACT) was 71.9 % (95 % CI 66.2-77.1 %). Findings show existence of asymptomatic malaria and walking anaemia among primary school children in Morogoro municipality. The majority of school children reported use of ITNs and ACT for malaria control. These findings provide a rationale for using schools and school children to assess effectiveness of malaria interventions.
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Snow, Robert W; Okiro, Emelda A; Gething, Peter W; Atun, Rifat; Hay, Simon I
2010-01-01
Summary Background Financing for malaria control has increased as part of international commitments to achieve the Millennium Development Goals (MDGs). We aimed to identify the unmet financial needs that would be biologically and economically equitable and would increase the chances of reaching worldwide malaria-control ambitions. Methods Populations at risk of stable Plasmodium falciparum or Plasmodium vivax transmission were calculated for 2007 and 2009 for 93 malaria-endemic countries to measure biological need. National per-person gross domestic product (GDP) was used to define economic need. An analysis of external donor assistance for malaria control was done for the period 2002–09 to compute overall and annualised per-person at-risk-funding commitments. Annualised malaria donor assistance was compared with independent predictions of funding needed to reach international targets of 80% coverage of best practices in case-management and effective disease prevention. Countries were ranked in relation to biological, economic, and unmet needs to examine equity and adequacy of support by 2010. Findings International financing for malaria control has increased by 166% (from $0·73 billion to $1·94 billion) since 2007 and is broadly consistent with biological needs. African countries have become major recipients of external assistance; however, countries where P vivax continues to pose threats to control ambitions are not as well funded. 21 countries have reached adequate assistance to provide a comprehensive suite of interventions by 2009, including 12 countries in Africa. However, this assistance was inadequate for 50 countries representing 61% of the worldwide population at risk of malaria—including ten countries in Africa and five in Asia that coincidentally are some of the poorest countries. Approval of donor funding for malaria control does not correlate with GDP. Interpretation Funding for malaria control worldwide is 60% lower than the US$4·9 billion
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2014-01-01
Abstract Background For many years, malaria has been one of the main health concerns of the government of Ghana. The government has recently implemented a control strategy which will ensure the inclusion of the community members who were previously excluded from the process. Until now, however, scientific study on this strategy has been scanty. Objectives The objectives were to investigate the level at which communities have been allowed to participate and to understand whether the idea of community participation in malaria control strategy is a myth or a reality. Methods Data were collected in the rural district of Ahafo-Ano South in the Ashanti region of Ghana. An exploratory qualitative approach was employed in order to ascertain the opinions of the local health officials and community members. The level of participation was measured using the framework of Arnstein's ‘ladder’ of participation, as developed in 1969. Results Evidence showed that the level of community participation was only tokenistic. Communities were only informed and/or consulted after decisions had been made, but the real engagement and negotiations were absent. Communities thus had limited opportunities to air their views in the planning process. Conclusion This article has revealed that the government's vision of ensuring community participation in the malaria control policy-making process can be said to be a myth rather than a reality. PMID:26245403
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Patent Medicine Sellers: How Can They Help Control Childhood Malaria?
Akuse, Rosamund M.; Eseigbe, Edwin E.; Ahmed, Abubakar; Brieger, William R.
2010-01-01
Roll Back Malaria Initiative encourages participation of private health providers in malaria control because mothers seek care for sick children from them. This study investigated Patent Medicine Sellers (PMS) management of presumptive malaria in children in order to identify how they can assist malaria control. A cross-sectional survey of 491 PMS in Kaduna, Nigeria, was done using interviews and observation of shop activities. Most (80%) customers bought drugs without prescriptions. Only 29.5% were given instructions about doses. Between 40–100% doses of recommended antimalarials were incorrect. Some (22%) PMS did not ask questions about illness for which they were consulted. Most children treated in shops received injections. PMS facilitate homecare but have deficiencies in knowledge and practice. Interventions must focus on training them to accurately determine doses, give advice about drug administration, use oral medication, and ask about illness. Training should be made a prerequisite for registering and reregistering shops. PMID:22332020
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Sun, Xing-sheng; Li, Li; Zhang, Kan-kan
2015-12-01
To understand the current status of malaria control knowledge awareness of primary and secondary school students and its influencing factors in Yunlong District, Xuzhou City, so as to provide the evidence for improving the malaria prevention work. A total of 800 students from 4 urban and rural primary and secondary schools were randomly selected and investigated with questionnaires. The total awareness rate of malaria control knowledge was 61.27%, and the awareness rates of symptoms of malaria and malaria prevention were only 38.99% and 57.59% respectively. The main approach of obtaining the malaria control knowledge was media (51.52%). The univariate analysis showed that sex, area and different education levels affected the awareness rates of malaria control knowledge (P < 0.05), and the Logistic analysis showed that the awareness rate of malaria control knowledge of country students was lower than that of urban students (P < 0.05), and the awareness rate of malaria control knowledge of the secondary school students was higher than that of the primary school students (P < 0.05). The awareness rate of malaria control knowledge of primary and secondary school students in Yunlong District is lower than that required by the national standard. Therefore, the health education of malaria control should be strengthened, especially in countryside school students and primary school students.
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Malaria Vector Control Still Matters despite Insecticide Resistance.
Alout, Haoues; Labbé, Pierrick; Chandre, Fabrice; Cohuet, Anna
2017-08-01
Mosquito vectors' resistance to insecticides is usually considered a major threat to the recent progresses in malaria control. However, studies measuring the impact of interventions and insecticide resistance reveal inconsistencies when using entomological versus epidemiological indices. First, evaluation tests that do not reflect the susceptibility of mosquitoes when they are infectious may underestimate insecticide efficacy. Moreover, interactions between insecticide resistance and vectorial capacity reveal nonintuitive outcomes of interventions. Therefore, considering ecological interactions between vector, parasite, and environment highlights that the impact of insecticide resistance on the malaria burden is not straightforward and we suggest that vector control still matters despite insecticide resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Hongvivatana, T
1986-09-01
Human behavior in malaria is often narrowly referred to behavior of the target populations in transmission and control of malaria. In this presentation it was discussed that such view is too narrow. A broader framework incorporating illness behavior and human behavior in malaria control bureaucracies is needed for the success of national malaria control programme. Literature under the three broad categories of human behavior in malaria is reviewed to justify future directions in human behavior research and their significance for successful malaria control.
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Malaria control in rural Malawi: implementing peer health education for behaviour change.
Malenga, Tumaini; Kabaghe, Alinune Nathanael; Manda-Taylor, Lucinda; Kadama, Asante; McCann, Robert S; Phiri, Kamija Samuel; van Vugt, Michèle; van den Berg, Henk
2017-11-20
Interventions to reduce malaria burden are effective if communities use them appropriately and consistently. Several tools have been suggested to promote uptake and use of malaria control interventions. Community workshops on malaria, using the 'Health Animator' approach, are a potential behaviour change strategy for malaria control. The strategy aims to influence a change in mind-set of vulnerable populations to encourage self-reliance, using community volunteers known as Health Animators. The aim of the paper is to describe the process of implementing community workshops on malaria by Health Animators to improve uptake and use of malaria control interventions in rural Malawi. This is a descriptive study reporting feasibility, acceptability, appropriateness and fidelity of using Health Animator-led community workshops for malaria control. Quantitative data were collected from self-reporting and researcher evaluation forms. Qualitative assessments were done with Health Animators, using three focus groups (October-December 2015) and seven in-depth interviews (October 2016-February 2017). Seventy seven health Animators were trained from 62 villages. A total of 2704 workshops were conducted, with consistent attendance from January 2015 to June 2017, representing 10-17% of the population. Attendance was affected by social responsibilities and activities, relationship of the village leaders and their community and involvement of Community Health Workers. Active discussion and participation were reported as main strengths of the workshops. Health Animators personally benefited from the mind-set change and were proactive peer influencers in the community. Although the information was comprehended and accepted, availability of adequate health services was a challenge for maintenance of behaviour change. Community workshops on malaria are a potential tool for influencing a positive change in behaviour towards malaria, and applicable for other health problems in rural
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Van Bortel, Wim; Trung, Ho Dinh; Hoi, Le Xuan; Van Ham, Nguyen; Van Chut, Nguyen; Luu, Nguyen Dinh; Roelants, Patricia; Denis, Leen; Speybroeck, Niko; D'Alessandro, Umberto; Coosemans, Marc
2010-12-23
In Vietnam, malaria is becoming progressively restricted to specific foci where human and vector characteristics alter the known malaria epidemiology, urging for alternative or adapted control strategies. Long-lasting insecticidal hammocks (LLIH) were designed and introduced in Ninh Thuan province, south-central Vietnam, to control malaria in the specific context of forest malaria. An entomological study in this specific forested environment was conducted to assess the behavioural patterns of forest and village vectors and to assess the spatio-temporal risk factors of malaria transmission in the province. Five entomological surveys were conducted in three villages in Ma Noi commune and in five villages in Phuoc Binh commune in Ninh Thuan Province, south-central Vietnam. Collections were made inside the village, at the plot near the slash-and-burn fields in the forest and on the way to the forest. All collected mosquito species were subjected to enzyme-linked immunosorbent assay (ELISA) to detect Plasmodium in the head-thoracic portion of individual mosquitoes after morphological identification. Collection data were analysed by use of correspondence and multivariate analyses. The mosquito density in the study area was low with on average 3.7 anopheline bites per man-night and 17.4 culicine bites per man-night. Plasmodium-infected mosquitoes were only found in the forest and on the way to the forest. Malaria transmission in the forested malaria foci was spread over the entire night, from dusk to dawn, but was most intense in the early evening as nine of the 13 Plasmodium positive bites occurred before 21H. The annual entomological inoculation rate of Plasmodium falciparum was 2.2 infective bites per person-year to which Anopheles dirus s.s. and Anopheles minimus s.s. contributed. The Plasmodium vivax annual entomological inoculation rate was 2.5 infective bites per person-year with Anopheles sawadwongporni, Anopheles dirus s.s. and Anopheles pampanai as vectors. The
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Water resources implications of integrating malaria control into the operation of an Ethiopian dam
NASA Astrophysics Data System (ADS)
Reis, Julia; Culver, Teresa B.; McCartney, Matthew; Lautze, Jonathan; Kibret, Solomon
2011-09-01
This paper investigates the water resources implications of using a method of hydrological control to reduce malaria around the Koka reservoir in central Ethiopia. This method is based on recent findings that malaria is transmitted from the shoreline of the Koka reservoir, and on a similar method that was used to control malaria some 80 yr ago in the United States. To assess the feasibility of implementing hydrological control at Koka, we considered the potential impact of the modified management regime on the benefits derived from current uses of the reservoir water (i.e., hydropower, irrigation, flood control, water supply, and downstream environmental flows). We used the HEC-ResSim model to simulate lowering the reservoir by a rate designed to disrupt larval development, which is expected to reduce the abundance of adult mosquito vectors and therefore reduce malaria transmission during the season in which transmission of the disease peaks. A comparison was made of major reservoir uses with and without the malaria control measure. In the 26-yr simulation, application of the malaria control measure increased total average annual electricity generation from 87.6 GWh × y-1 to 92.2 GWh × y-1 (i.e., a 5.3% increase) but resulted in a small decline in firm power generation (i.e., guaranteed at 99.5% reliability) from 4.16 MW to 4.15 MW (i.e., a 0.2% decrease). Application of the malaria control measure did not impact the ability of the reservoir to meet downstream irrigation demand and reduced the number of days of downstream flooding from 28 to 24 d. These results indicate that targeted use of hydrological control for malaria vector management could be undertaken without sacrificing the key benefits of reservoir operation.
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Disrupting Mosquito Reproduction and Parasite Development for Malaria Control
Gabrieli, Paolo; Buckee, Caroline O.; Catteruccia, Flaminia
2016-01-01
The control of mosquito populations with insecticide treated bed nets and indoor residual sprays remains the cornerstone of malaria reduction and elimination programs. In light of widespread insecticide resistance in mosquitoes, however, alternative strategies for reducing transmission by the mosquito vector are urgently needed, including the identification of safe compounds that affect vectorial capacity via mechanisms that differ from fast-acting insecticides. Here, we show that compounds targeting steroid hormone signaling disrupt multiple biological processes that are key to the ability of mosquitoes to transmit malaria. When an agonist of the steroid hormone 20-hydroxyecdysone (20E) is applied to Anopheles gambiae females, which are the dominant malaria mosquito vector in Sub Saharan Africa, it substantially shortens lifespan, prevents insemination and egg production, and significantly blocks Plasmodium falciparum development, three components that are crucial to malaria transmission. Modeling the impact of these effects on Anopheles population dynamics and Plasmodium transmission predicts that disrupting steroid hormone signaling using 20E agonists would affect malaria transmission to a similar extent as insecticides. Manipulating 20E pathways therefore provides a powerful new approach to tackle malaria transmission by the mosquito vector, particularly in areas affected by the spread of insecticide resistance. PMID:27977810
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Efficacy and cost-effectiveness of environmental management for malaria control.
Utzinger, J; Tozan, Y; Singer, B H
2001-09-01
Roll back malaria (RBM) aims at halving the current burden of the disease by the year 2010. The focus is on sub-Saharan Africa, and it is proposed to implement efficacious and cost-effective control strategies. But the evidence base of such information is scarce, and a notable missing element is the discussion of the potential of environmental management. We reviewed the literature and identified multiple malaria control programmes that incorporated environmental management as the central feature. Prominent among them are programmes launched in 1929 and implemented for two decades at copper mining communities in Zambia. The full package of control measures consisted of vegetation clearance, modification of river boundaries, draining swamps, oil application to open water bodies and house screening. Part of the population also was given quinine and was sleeping under mosquito nets. Monthly malaria incidence rates and vector densities were used for surveillance and adaptive tuning of the environmental management strategies to achieve a high level of performance. Within 3-5 years, malaria-related mortality, morbidity and incidence rates were reduced by 70-95%. Over the entire 20 years of implementation, the programme had averted an estimated 4173 deaths and 161,205 malaria attacks. The estimated costs per death and malaria attack averted were US$ 858 and US$ 22.20, respectively. Over the initial 3-5 years start-up period, analogous to the short-duration of cost-effectiveness analyses of current studies, we estimated that the costs per disability adjusted life year (DALY) averted were US$ 524-591. However, the strategy has a track record of becoming cost-effective in the longer term, as maintenance costs were much lower: US$ 22-92 per DALY averted. In view of fewer adverse ecological effects, increased sustainability and better uses of local resources and knowledge, environmental management--integrated with pharmacological, insecticidal and bednet interventions
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Use and Effects of Malaria Control Measures in Pregnancy in Lagos, Nigeria
Amoo, A. O. J.; Akintunde, Grace B.; Ojelekan, Oluwole D.; König, Wolfgang; König, Brigitte
2011-01-01
In Nigeria, malaria causes up to 11% of maternal mortality. Our main aim was to find out the most common mosquito control measures employed by the pregnant women in Lagos and their effects on malaria infection. The study was carried out over a period of 6 months during which trained interviewers administered questionnaires to 400 pregnant women. The prevalence of malaria was 8.4%. There was no significant association between the prevalence of malaria and age, level of education, or occupation of the participants. Pregnant women in the age range 26-30 had the mean parasite density (409.9±196.80). Insecticide spray (32.8%), mosquito coil (27.5%), and insecticide-treated nets (ITN) (15.5%) were the major mosquito control measures employed by the participants while the prevalence of infection among them were 2.3%, 6.2%, and 3.2%, respectively (P<0.05). Only 18.3% of the women had taken more than one dose of intermittent preventive treatment (IPT), while another 11.8% had taken a single dose. The infection rate among them was 4.1% and 6.4%, respectively. Malaria prevalence was highest among those who had not received any dose of IPT (10%). This study showed that the use of ITN and IPT among the pregnant women were still unacceptably low. It also showed that the use of insecticide spray which was the most common malaria control measure adopted by the participants was effective despite the fact that it is not a National Malaria Control Policy. We recommend that a sustained integrated mosquito management and public education should be strengthened in Nigeria. PMID:22355203
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Nyasembe, Vincent O.; Tchouassi, David P.; Kirwa, Hillary K.; Foster, Woodbridge A.; Teal, Peter E. A.; Borgemeister, Christian; Torto, Baldwyn
2014-01-01
Background Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based synthetic odor baits in trapping outdoor populations of malaria vectors. Methodology and Principal Finding Three plant-based lures ((E)-linalool oxide [LO], (E)-linalool oxide and (E)-β-ocimene [LO + OC], and a six-component blend comprising (E)-linalool oxide, (E)-β-ocimene, hexanal, β-pinene, limonene, and (E)-β-farnesene [Blend C]), were tested alongside an animal/human-based synthetic lure (comprising heptanal, octanal, nonanal, and decanal [Blend F]) and worn socks in a malaria endemic zone in the western part of Kenya. Mosquito Magnet-X (MM-X) and lightless Centre for Disease Control (CDC) light traps were used. Odor-baited traps were compared with traps baited with either solvent alone or solvent + carbon dioxide (controls) for 18 days in a series of randomized incomplete-block designs of days × sites × treatments. The interactive effect of plant and animal/human odor was also tested by combining LO with either Blend F or worn socks. Our results show that irrespective of trap type, traps baited with synthetic plant odors compared favorably to the same traps baited with synthetic animal odors and worn socks in trapping malaria vectors, relative to the controls. Combining LO and worn socks enhanced trap captures of Anopheles species while LO + Blend F recorded reduced trap capture. Carbon dioxide enhanced total trap capture of both plant- and animal/human-derived odors. However, significantly higher proportions of male and engorged female Anopheles gambiae s.l. were caught when the odor treatments did not include carbon dioxide. Conclusion and Significance The results highlight the potential of plant-based odors and specifically linalool oxide, with or
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Targeting male mosquito swarms to control malaria vector density
Sawadogo, Simon Peguedwinde; Niang, Abdoulaye; Bilgo, Etienne; Millogo, Azize; Maïga, Hamidou; Dabire, Roch K.; Tripet, Frederic; Diabaté, Abdoulaye
2017-01-01
Malaria control programs are being jeopardized by the spread of insecticide resistance in mosquito vector populations. It has been estimated that the spread of resistance could lead to an additional 120000 deaths per year, and interfere with the prospects for sustained control or the feasibility of achieving malaria elimination. Another complication for the development of resistance management strategies is that, in addition to insecticide resistance, mosquito behavior evolves in a manner that diminishes the impact of LLINs and IRS. Mosquitoes may circumvent LLIN and IRS control through preferential feeding and resting outside human houses and/or being active earlier in the evening before people go to sleep. Recent developments in our understanding of mosquito swarming suggest that new tools targeting mosquito swarms can be designed to cut down the high reproductive rate of malaria vectors. Targeting swarms of major malaria vectors may provide an effective control method to counteract behavioral resistance developed by mosquitoes. Here, we evaluated the impact of systematic spraying of swarms of Anopheles gambiae s.l. using a mixed carbamate and pyrethroid aerosol. The impact of this intervention on vector density, female insemination rates and the age structure of males was measured. We showed that the resulting mass killing of swarming males and some mate-seeking females resulted in a dramatic 80% decrease in population size compared to a control population. A significant decrease in female insemination rate and a significant shift in the age structure of the male population towards younger males incapable of mating were observed. This paradigm-shift study therefore demonstrates that targeting primarily males rather than females, can have a drastic impact on mosquito population. PMID:28278212
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The complexities of malaria disease manifestations with a focus on asymptomatic malaria
2012-01-01
Malaria is a serious parasitic disease in the developing world, causing high morbidity and mortality. The pathogenesis of malaria is complex, and the clinical presentation of disease ranges from severe and complicated, to mild and uncomplicated, to asymptomatic malaria. Despite a wealth of studies on the clinical severity of disease, asymptomatic malaria infections are still poorly understood. Asymptomatic malaria remains a challenge for malaria control programs as it significantly influences transmission dynamics. A thorough understanding of the interaction between hosts and parasites in the development of different clinical outcomes is required. In this review, the problems and obstacles to the study and control of asymptomatic malaria are discussed. The human and parasite factors associated with differential clinical outcomes are described and the management and treatment strategies for the control of the disease are outlined. Further, the crucial gaps in the knowledge of asymptomatic malaria that should be the focus of future research towards development of more effective malaria control strategies are highlighted. PMID:22289302
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Moore, Sarah J; Min, Xia; Hill, Nigel; Jones, Caroline; Zaixing, Zhang; Cameron, Mary M
2008-10-01
Malaria control in remote, forested areas of the Mekong region relies on personal protection from mosquito bites. Uptake of these methods may be limited by knowledge of the link between mosquitoes and malaria as well as social and economic aspects. Understanding barriers to uptake will inform malaria control programmes on targets for improvement of delivery. A total 748 key respondents: health providers and village heads, from 187 villages and 25 different ethnic groups, were interviewed using structured questionnaires. Differences in use of personal protection, and knowledge of malaria between groups were analysed using chi-square; and binary logistic regression used for multivariate analysis. Malaria knowledge was poor with 19.4% of women and 37.5% of men linking mosquitoes with malaria, although 95.6% knew one or more methods of mosquito control. Virtually all respondents used personal protection at some time during the year; and understanding of malaria transmission was strongly associated with bednet use. Those working in forest agriculture were significantly more likely to know that mosquitoes transmit malaria but this did not translate into a significantly greater likelihood of using bednets. Furthermore, use of personal protection while woing outdoors was rare, and less than 3% of respondents knew about the insecticide impregnation of bednets. The use of bednets, synthetic repellents and mosquito coils varied between ethnic groups, but was significantly more frequent among those with higher income, more years of education and permanent housing. The reported use of repellents and coils was also more common among women despite their low knowledge of malaria transmission, and low likelihood of having heard information on malaria within the last year. The use of personal protection must be increased, particularly among outdoor workers that have higher malaria risk. However, personal protection is widely used and widely accepted to prevent nuisance biting
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Malaria Risk Mapping for Control in the Republic of Sudan
Noor, Abdisalan M.; ElMardi, Khalid A.; Abdelgader, Tarig M.; Patil, Anand P.; Amine, Ahmed A. A.; Bakhiet, Sahar; Mukhtar, Maowia M.; Snow, Robert W.
2012-01-01
Evidence shows that malaria risk maps are rarely tailored to address national control program ambitions. Here, we generate a malaria risk map adapted for malaria control in Sudan. Community Plasmodium falciparum parasite rate (PfPR) data from 2000 to 2010 were assembled and were standardized to 2–10 years of age (PfPR2–10). Space-time Bayesian geostatistical methods were used to generate a map of malaria risk for 2010. Surfaces of aridity, urbanization, irrigation schemes, and refugee camps were combined with the PfPR2–10 map to tailor the epidemiological stratification for appropriate intervention design. In 2010, a majority of the geographical area of the Sudan had risk of < 1% PfPR2–10. Areas of meso- and hyperendemic risk were located in the south. About 80% of Sudan's population in 2011 was in the areas in the desert, urban centers, or where risk was < 1% PfPR2–10. Aggregated data suggest reducing risks in some high transmission areas since the 1960s. PMID:23033400
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She, Guo-lin; Ma, Yu-Cai; Wang, Fu-biao
2013-08-01
To analyze the current situation of the comprehensive prevention and control system for imported falciparum malaria in Hanjiang District and evaluate its effect. According to the Management Scheme on Control of Imported Falciparum Malaria in Yangzhou City, the comprehensive prevention and control system for imported falciparum malaria was implemented, and the relevant malaria data were collected and analyzed statistically. The data included plasmodium blood test ratio of fever patients among exported labors and those returned, the ratio of laboratory-confirmed cases among all reported cases of falciparum malaria, the ratio of falciparum malaria patients who received the standard treatment within 24 hours after onset, etc from 2010 to 2012. After the implementation of the comprehensive prevention and control system, the confirmation ratio of falciparum malaria cases within 24 hours following first visit has reached 60.47%, the average time from first visit to confirmation has shortened to 1.8 d, and the average time from onset to confirmation has shortened to 3.7 d. The health education coverage ratio was 100%, the health knowledge awareness ratio was 95.56%, the ratio of patients seeking treatment on own initiative was 100%, the laboratory-confirmed ratio was 100%, and the ratio of standard treatment after malaria diagnosis was 100%. The comprehensive prevention and control system carried out by Hanjiang District has made remarkable achievements.
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Optimal control of malaria: combining vector interventions and drug therapies.
Khamis, Doran; El Mouden, Claire; Kura, Klodeta; Bonsall, Michael B
2018-04-24
The sterile insect technique and transgenic equivalents are considered promising tools for controlling vector-borne disease in an age of increasing insecticide and drug-resistance. Combining vector interventions with artemisinin-based therapies may achieve the twin goals of suppressing malaria endemicity while managing artemisinin resistance. While the cost-effectiveness of these controls has been investigated independently, their combined usage has not been dynamically optimized in response to ecological and epidemiological processes. An optimal control framework based on coupled models of mosquito population dynamics and malaria epidemiology is used to investigate the cost-effectiveness of combining vector control with drug therapies in homogeneous environments with and without vector migration. The costs of endemic malaria are weighed against the costs of administering artemisinin therapies and releasing modified mosquitoes using various cost structures. Larval density dependence is shown to reduce the cost-effectiveness of conventional sterile insect releases compared with transgenic mosquitoes with a late-acting lethal gene. Using drug treatments can reduce the critical vector control release ratio necessary to cause disease fadeout. Combining vector control and drug therapies is the most effective and efficient use of resources, and using optimized implementation strategies can substantially reduce costs.
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Efficacy of local neem extracts for sustainable malaria vector control in an African village
Gianotti, Rebecca L; Bomblies, Arne; Dafalla, Mustafa; Issa-Arzika, Ibrahim; Duchemin, Jean-Bernard; Eltahir, Elfatih AB
2008-01-01
Background Larval control of malaria vectors has been historically successful in reducing malaria transmission, but largely fell out of favour with the introduction of synthetic insecticides and bed nets. However, an integrated approach to malaria control, including larval control methods, continues to be the best chance for success, in view of insecticide resistance, the behavioural adaptation of the vectors to changing environments and the difficulties of reaching the poorest populations most at risk,. Laboratory studies investigating the effects of neem seed (Azadirachta indica) extracts on Anopheles larvae have shown high rates of larval mortality and reductions in adult longevity, as well as low potential for resistance development. Methods This paper describes a method whereby seeds of the neem tree can be used to reduce adult Anopheles gambiae s.l. abundance in a way that is low cost and can be implemented by residents of rural villages in western Niger. The study was conducted in Banizoumbou village, western Niger. Neem seeds were collected from around the village. Dried seeds were ground into a coarse powder, which was then sprinkled onto known Anopheles larvae breeding habitats twice weekly during the rainy season 2007. Adult mosquitoes were captured on a weekly basis in the village and captures compared to those from 2005 and 2006 over the same period. Adult mosquitoes were also captured in a nearby village, Zindarou, as a control data set and compared to those from Banizoumbou. Results It was found that twice-weekly applications of the powder to known breeding habitats of Anopheles larvae in 2007 resulted in 49% fewer adult female Anopheles gambiae s.l. mosquitoes in Banizoumbou, compared with previous captures under similar environmental conditions and with similar habitat characteristics in 2005 and 2006. The productivity of the system in 2007 was found to be suppressed compared to the mean behaviour of 2005 and 2006 in Banizoumbou, whereas no change
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Aung, P Linn; Silawan, Tassanee; Rawiworrakul, Tassanee; Min, Myo
2018-01-01
Village health volunteers (VHVs) are key agents for malaria control in community. The Myanmar Medical Association-Malaria (MMA-Malaria) Project has promoted effective malaria control in endemic and high-risk townships by supporting roles of VHVs. To assess the roles of VHVs on malaria control and factors enhancing their roles in rural Myanmar. A cross-sectional study was conducted in five townships where the MMA-Malaria Project has been implemented. One hundred and fifty VHVs were sampled from five townships by simple random sampling. Data were collected by trained interviewers using structured questionnaires, which covered sociodemographic, supportive, motivational factors, and roles of malaria control. Studied variables were described by proportions, means, and standard deviations and were analyzed for their association by odds ratio with 95% confidence interval and Chi-square tests. Most of VHVs (96%) expected to demonstrate good roles on malaria control, but only 44.0% exhibited current roles at a good level. Factors enhancing their roles were female (P = 0.037), family income ≥50,001 kyat/month (P < 0.015), time serving as a volunteer 1-2 years (P = 0.006), good knowledge of malaria control (P < 0.001), good family support (P < 0.001), good community support (P < 0.001), and good motivational factors (P = 0.002). VHVs are key agents for malaria control in community. Most of VHVs expected to demonstrate good roles on malaria control, but less than half of them exhibited current roles at a good level. The systems and program for improving VHVs' knowledge, encouraging family and community support, and promoting motivation are essential for their better roles.
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Jima, Daddi; Getachew, Asefaw; Bilak, Hana; Steketee, Richard W; Emerson, Paul M; Graves, Patricia M; Gebre, Teshome; Reithinger, Richard; Hwang, Jimee
2010-02-24
In 2005, a nationwide survey estimated that 6.5% of households in Ethiopia owned an insecticide-treated net (ITN), 17% of households had been sprayed with insecticide, and 4% of children under five years of age with a fever were taking an anti-malarial drug. Similar to other sub-Saharan African countries scaling-up malaria interventions, the Government of Ethiopia set an ambitious national goal in 2005 to (i) provide 100% ITN coverage in malarious areas, with a mean of two ITNs per household; (ii) to scale-up indoor residual spraying of households with insecticide (IRS) to cover 30% of households targeted for IRS; and (iii) scale-up the provision of case management with rapid diagnostic tests (RDTs) and artemisinin-based combination therapy (ACT), particularly at the peripheral level. A nationally representative malaria indicator survey (MIS) was conducted in Ethiopia between September and December 2007 to determine parasite and anaemia prevalence in the population at risk and to assess coverage, use and access to scaled-up malaria prevention and control interventions. The survey used a two-stage random cluster sample of 7,621 households in 319 census enumeration areas. A total of 32,380 people participated in the survey. Data was collected using standardized Roll Back Malaria Monitoring and Evaluation Reference Group MIS household and women's questionnaires, which were adapted to the local context. Data presented is for households in malarious areas, which according to the Ethiopian Federal Ministry of Health are defined as being located <2,000 m altitude. Of 5,083 surveyed households, 3,282 (65.6%) owned at least one ITN. In ITN-owning households, 53.2% of all persons had slept under an ITN the prior night, including 1,564/2,496 (60.1%) children <5 years of age, 1,891/3,009 (60.9%) of women 15 - 49 years of age, and 166/266 (65.7%) of pregnant women. Overall, 906 (20.0%) households reported to have had IRS in the past 12 months. Of 747 children with reported
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Ebhuoma, Osadolor; Gebreslasie, Michael; Magubane, Lethumusa
The change of the malaria control intervention policy in South Africa (SA), re-introduction of dichlorodiphenyltrichloroethane (DDT), may be responsible for the low and sustained malaria transmission in KwaZulu-Natal (KZN). We evaluated the effect of the re-introduction of DDT on malaria in KZN and suggested practical ways the province can strengthen her already existing malaria control and elimination efforts, to achieve zero malaria transmission. We obtained confirmed monthly malaria cases in KZN from the malaria control program of KZN from 1998 to 2014. The seasonal autoregressive integrated moving average (SARIMA) intervention time series analysis (ITSA) was employed to model the effect of the re-introduction of DDT on confirmed monthly malaria cases. The result is an abrupt and permanent decline of monthly malaria cases (w 0 =-1174.781, p-value=0.003) following the implementation of the intervention policy. The sustained low malaria cases observed over a long period suggests that the continued usage of DDT did not result in insecticide resistance as earlier anticipated. It may be due to exophagic malaria vectors, which renders the indoor residual spraying not totally effective. Therefore, the feasibility of reducing malaria transmission to zero in KZN requires other reliable and complementary intervention resources to optimize the existing ones. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Barriers to malaria control in rural south-west Timor-Leste: a qualitative analysis.
Neave, Penny E; Soares, Maria L
2014-01-01
Malaria is an important health problem in Timor-Leste. Although funding has been provided to reduce the burden of this disease, few studies have investigated whether this has improved malaria-related knowledge, management of symptoms, and treatment in rural communities. The aim of this study was to explore the perceptions and practices undertaken in relation to all aspects of malaria control by members of two rural communities in Timor-Leste. A qualitative study was undertaken in two rural hamlets in Timor-Leste. Research methods included transect walks, focus groups and semi-structured interviews. Content analysis was used to identify themes. The location of the hamlets near rice fields, leaking taps, inadequate water supplies and dumping of waste from the local hospital provided opportunities for mosquitoes to breed. Most participants were aware of the link between mosquitoes and malaria, but a lack of control over their environment was a major barrierto preventing malaria. The distribution ofbed nets had occurred once, and was the only intervention undertaken bythe National Malaria Control Programme. However, limiting the distribution of bed nets to pregnant women and children aged under 5 years had resulted in some focus group respondents believing that only those in these groups could be affected by malaria. Self-diagnosis and home treatmentwere common. Treatment for unresolved infections depended on access to transport funds, and belief in the power of traditional healers. Improvements in infrastructure, empowerment of rural communities, and better access to treatment are recommended if the incidence of malaria is to be reduced throughout the country.
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Evidence and strategies for malaria prevention and control: a historical analysis.
Gachelin, Gabriel; Garner, Paul; Ferroni, Eliana; Verhave, Jan Peter; Opinel, Annick
2018-02-27
Public health strategies for malaria in endemic countries aim to prevent transmission of the disease and control the vector. This historical analysis considers the strategies for vector control developed during the first four decades of the twentieth century. In 1925, policies and technological advances were debated internationally for the first time after the outbreak of malaria in Europe which followed World War I. This dialogue had implications for policies in Europe, Russia and the Middle East, and influenced the broader international control agenda. The analysis draws on the advances made before 1930, and includes the effects of mosquito-proofing of houses; the use of larvicides (Paris Green) and larvivorous fish (Gambusia); the role of large-scale engineering works; and the emergence of biological approaches to malaria. The importance of strong government and civil servant support was outlined. Despite best efforts of public health authorities, it became clear that it was notoriously difficult to interrupt transmission in areas of moderately high transmission. The importance of combining a variety of measures to achieve control became clear and proved successful in Palestine between 1923 and 1925, and improved education, economic circumstances and sustained political commitment emerge as key factors in the longer term control of malaria. The analysis shows that the principles for many of the present public health strategies for malaria have nearly all been defined before 1930, apart from large scale usage of pesticides, which came later at the end of the Second World War. No single intervention provided an effective single answer to preventing transmission, but certainly approaches taken that are locally relevant and applied in combination, are relevant to today's efforts at elimination.
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Malaria ecotypes and stratification.
Schapira, Allan; Boutsika, Konstantina
2012-01-01
To deal with the variability of malaria, control programmes need to stratify their malaria problem into a number of smaller units. Such stratification may be based on the epidemiology of malaria or on its determinants such as ecology. An ecotype classification was developed by the World Health Organization (WHO) around 1990, and it is time to assess its usefulness for current malaria control as well as for malaria modelling on the basis of published research. Journal and grey literature was searched for articles on malaria or Anopheles combined with ecology or stratification. It was found that all malaria in the world today could be assigned to one or more of the following ecotypes: savanna, plains and valleys; forest and forest fringe; foothill; mountain fringe and northern and southern fringes; desert fringe; coastal and urban. However, some areas are in transitional or mixed zones; furthermore, the implications of any ecotype depend on the biogeographical region, sometimes subregion, and finally, the knowledge on physiography needs to be supplemented by local information on natural, anthropic and health system processes including malaria control. Ecotyping can therefore not be seen as a shortcut to determine control interventions, but rather as a framework to supplement available epidemiological and entomological data so as to assess malaria situations at the local level, think through the particular risks and opportunities and reinforce intersectoral action. With these caveats, it does however emerge that several ecotypic distinctions are well defined and have relatively constant implications for control within certain biogeographic regions. Forest environments in the Indo-malay and the Neotropics are, with a few exceptions, associated with much higher malaria risk than in adjacent areas; the vectors are difficult to control, and the anthropic factors also often converge to impose constraints. Urban malaria in Africa is associated with lower risk than savanna
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Muela Ribera, Joan; Ngo Duc, Thang; van Bortel, Wim; Truong Ba, Nhat; Van, Ky Pham; Le Xuan, Hung; D'Alessandro, Umberto; Erhart, Annette
2012-01-01
Background Long-lasting insecticidal hammocks (LLIHs) are being evaluated as an additional malaria prevention tool in settings where standard control strategies have a limited impact. This is the case among the Ra-glai ethnic minority communities of Ninh Thuan, one of the forested and mountainous provinces of Central Vietnam where malaria morbidity persist due to the sylvatic nature of the main malaria vector An. dirus and the dependence of the population on the forest for subsistence - as is the case for many impoverished ethnic minorities in Southeast Asia. Methods A social science study was carried out ancillary to a community-based cluster randomized trial on the effectiveness of LLIHs to control forest malaria. The social science research strategy consisted of a mixed methods study triangulating qualitative data from focused ethnography and quantitative data collected during a malariometric cross-sectional survey on a random sample of 2,045 study participants. Results To meet work requirements during the labor intensive malaria transmission and rainy season, Ra-glai slash and burn farmers combine living in government supported villages along the road with a second home at their fields located in the forest. LLIH use was evaluated in both locations. During daytime, LLIH use at village level was reported by 69.3% of all respondents, and in forest fields this was 73.2%. In the evening, 54.1% used the LLIHs in the villages, while at the fields this was 20.7%. At night, LLIH use was minimal, regardless of the location (village 4.4%; forest 6.4%). Discussion Despite the free distribution of insecticide-treated nets (ITNs) and LLIHs, around half the local population remains largely unprotected when sleeping in their forest plot huts. In order to tackle forest malaria more effectively, control policies should explicitly target forest fields where ethnic minority farmers are more vulnerable to malaria. PMID:22253852
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Seasonal prevalence of malaria in West Sumba district, Indonesia
Syafruddin, Din; Krisin; Asih, Puji; Sekartuti; Dewi, Rita M; Coutrier, Farah; Rozy, Ismail E; Susanti, Augustina I; Elyazar, Iqbal RF; Sutamihardja, Awalludin; Rahmat, Agus; Kinzer, Michael; Rogers, William O
2009-01-01
Background Accurate information about the burden of malaria infection at the district or provincial level is required both to plan and assess local malaria control efforts. Although many studies of malaria epidemiology, immunology, and drug resistance have been conducted at many sites in Indonesia, there is little published literature describing malaria prevalence at the district, provincial, or national level. Methods Two stage cluster sampling malaria prevalence surveys were conducted in the wet season and dry season across West Sumba, Nusa Tenggara Province, Indonesia. Results Eight thousand eight hundred seventy samples were collected from 45 sub-villages in the surveys. The overall prevalence of malaria infection in the West Sumba District was 6.83% (95% CI, 4.40, 9.26) in the wet season and 4.95% (95% CI, 3.01, 6.90) in the dry. In the wet season Plasmodium falciparum accounted for 70% of infections; in the dry season P. falciparum and Plasmodium vivax were present in equal proportion. Malaria prevalence varied substantially across the district; prevalences in individual sub-villages ranged from 0–34%. The greatest malaria prevalence was in children and teenagers; the geometric mean parasitaemia in infected individuals decreased with age. Malaria infection was clearly associated with decreased haemoglobin concentration in children under 10 years of age, but it is not clear whether this association is causal. Conclusion Malaria is hypoendemic to mesoendemic in West Sumba, Indonesia. The age distribution of parasitaemia suggests that transmission has been stable enough to induce some clinical immunity. These prevalence data will aid the design of future malaria control efforts and will serve as a baseline against which the results of current and future control efforts can be assessed. PMID:19134197
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Identification and Optimization of New Leads for Malaria Vector Control.
Hueter, Ottmar F; Hoppé, Mark; Wege, Philip; Maienfisch, Peter
2016-10-01
A significant proportion of the world's population remains at risk from malaria, and whilst great progress has been made in reducing the number of malaria cases globally through the use of vector control insecticides, these gains are under threat from the emergence of insecticide resistance. The spread of resistance in the vector populations, principally to pyrethroids, is driving the need for the development of new tools for malaria vector control. In order to identify new leads 30,000 compounds from the Syngenta corporate chemical collection were tested in a newly developed screening platform. More than 3000 compounds (10%) showed activity at ≤200 mg active ingredient (AI) litre -1 against Anopheles stephensi. Further evaluation resulted in the identification of 12 viable leads for the control of adult mosquitoes, most originating from current or former insecticide projects. Surprisingly, one of these leads emerged from a former PPO herbicide project and one from a former complex III fungicide project. This indicates that representatives of certain herbicide and fungicide projects and modes of action can also represent a valuable source of leads for malaria vector control. Optimization of the diphenyl ether lead 1 resulted in the identification of the cyano-pyridyl compound 31. This compound 31 exhibits good activity against mosquito species including rdl resistant Anopheles. It is only slightly weaker than permethrin and does not show relevant levels of cross-resistance to the organochlorine insecticide dieldrin.
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Girum, Tadele; Hailemikael, Gebremariam; Wondimu, Asegedech
2017-01-01
Globally malaria remains one of the most severe public health problems resulting in massive morbidity particularly in developing countries. Ethiopia as one of the sub-Saharan country it is highly endemic to malaria. It was noted that early detection and prompt treatment of malaria cases, selective vector control and epidemic prevention and control are the major strategies for malaria prevention and control; So far, a lot have been done and remarkable improvements were seen. However, in what extent the prevention strategy was running in the community and what factors are hindering the prevention strategy at community level was not well known in Ethiopia. Therefore this study aimed to assess measures taken to prevent malaria and associated factors among households in Gurage zone, south Ethiopia. Community based cross- sectional study was conducted in Gurage zone, southern Ethiopia . A total of 817 randomly selected households were included in the study. After checking for completeness the data was entered in to Epi info 7 and analyzed through SPSS (Statistical Package for Social Sciences) version 21. Descriptive summary was computed and presented by tables, graphs and figures. After checking for assumptions Bivariate analysis was run to look for the association between dependent and explanatory variables; and using variables which have p -value ≤0.25 binary logistic regression was fitted. Association was presented in Odds ratio with 95% confidence interval and significance determined at P -value less than 0.05. Goodness of fit of the final model checked by Hosmer and Lemshow test. Overall 496 (62%) of households practiced good measure of malaria prevention and control. Educated households (AOR = 2.15 (95% CI [1.21-4.67]), higher wealth index (AOR = 3.3 (95% CI [2.3-6.2]), iron corrugated house owners (AOR = 2.7 (95% CI [1.7-3.5]), who received ITN from HC (AOR = 3.6 (95% CI [1.7-4.5] and involved in malaria prevention campaign AOR = 2.6, (95% CI
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Global investment targets for malaria control and elimination between 2016 and 2030.
Patouillard, Edith; Griffin, Jamie; Bhatt, Samir; Ghani, Azra; Cibulskis, Richard
2017-01-01
Access to malaria control interventions falls short of universal health coverage. The Global Technical Strategy for malaria targets at least 90% reduction in case incidence and mortality rates, and elimination in 35 countries by 2030. The potential to reach these targets will be determined in part by investments in malaria. This study estimates the financing required for malaria control and elimination over the 2016-2030 period. A mathematical transmission model was used to explore the impact of increasing intervention coverage on burden and costs. The cost analysis took a public provider perspective covering all 97 malaria endemic countries and territories in 2015. All control interventions currently recommended by the WHO were considered. Cost data were sourced from procurement databases, the peer-reviewed literature, national malaria strategic plans, the WHO-CHOICE project and key informant interviews. Annual investments of $6.4 billion (95% uncertainty interval (UI $4.5-$9.0 billion)) by 2020, $7.7 billion (95% UI $5.4-$10.9 billion) by 2025 and $8.7 billion (95% UI $6.0-$12.3 billion) by 2030 will be required to reach the targets set in the Global Technical Strategy. These are equivalent to annual investment per person at risk of malaria of US$3.90 by 2020, US$4.30 by 2025 and US$4.40 by 2030, compared with US$2.30 if interventions were sustained at current coverage levels. The 20 countries with the highest burden in 2015 will require 88% of the total investment. Given the challenges in increasing domestic and international funding, the efficient use of currently available resources should be a priority.
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Using Rainfall and Temperature Data in the Evaluation of National Malaria Control Programs in Africa
Thomson, Madeleine C.; Ukawuba, Israel; Hershey, Christine L.; Bennett, Adam; Ceccato, Pietro; Lyon, Bradfield; Dinku, Tufa
2017-01-01
Abstract. Since 2010, the Roll Back Malaria (RBM) Partnership, including National Malaria Control Programs, donor agencies (e.g., President's Malaria Initiative and Global Fund), and other stakeholders have been evaluating the impact of scaling up malaria control interventions on all-cause under-five mortality in several countries in sub-Saharan Africa. The evaluation framework assesses whether the deployed interventions have had an impact on malaria morbidity and mortality and requires consideration of potential nonintervention influencers of transmission, such as drought/floods or higher temperatures. Herein, we assess the likely effect of climate on the assessment of the impact malaria interventions in 10 priority countries/regions in eastern, western, and southern Africa for the President's Malaria Initiative. We used newly available quality controlled Enhanced National Climate Services rainfall and temperature products as well as global climate products to investigate likely impacts of climate on malaria evaluations and test the assumption that changing the baseline period can significantly impact on the influence of climate in the assessment of interventions. Based on current baseline periods used in national malaria impact assessments, we identify three countries/regions where current evaluations may overestimate the impact of interventions (Tanzania, Zanzibar, Uganda) and three countries where current malaria evaluations may underestimate the impact of interventions (Mali, Senegal and Ethiopia). In four countries (Rwanda, Malawi, Mozambique, and Angola) there was no strong difference in climate suitability for malaria in the pre- and post-intervention period. In part, this may be due to data quality and analysis issues. PMID:28990912
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Thomson, Madeleine C; Ukawuba, Israel; Hershey, Christine L; Bennett, Adam; Ceccato, Pietro; Lyon, Bradfield; Dinku, Tufa
2017-09-01
Since 2010, the Roll Back Malaria (RBM) Partnership, including National Malaria Control Programs, donor agencies (e.g., President's Malaria Initiative and Global Fund), and other stakeholders have been evaluating the impact of scaling up malaria control interventions on all-cause under-five mortality in several countries in sub-Saharan Africa. The evaluation framework assesses whether the deployed interventions have had an impact on malaria morbidity and mortality and requires consideration of potential nonintervention influencers of transmission, such as drought/floods or higher temperatures. Herein, we assess the likely effect of climate on the assessment of the impact malaria interventions in 10 priority countries/regions in eastern, western, and southern Africa for the President's Malaria Initiative. We used newly available quality controlled Enhanced National Climate Services rainfall and temperature products as well as global climate products to investigate likely impacts of climate on malaria evaluations and test the assumption that changing the baseline period can significantly impact on the influence of climate in the assessment of interventions. Based on current baseline periods used in national malaria impact assessments, we identify three countries/regions where current evaluations may overestimate the impact of interventions (Tanzania, Zanzibar, Uganda) and three countries where current malaria evaluations may underestimate the impact of interventions (Mali, Senegal and Ethiopia). In four countries (Rwanda, Malawi, Mozambique, and Angola) there was no strong difference in climate suitability for malaria in the pre- and post-intervention period. In part, this may be due to data quality and analysis issues.
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Durrheim, D N; Govere, J; la Grange, J J; Mabuza, A
2001-01-01
Malaria is a re-emerging disease in much of Africa. In response, the World Health Organization launched the Roll Back Malaria (RBM) initiative. One of six key principles adopted is the early detection of malaria cases. However, the importance of definitive diagnosis and potential value of field deployment of rapid malaria tests in RBM has been largely ignored. The Lowveld Region of Mpumalanga Province, South Africa, is home to a predominantly non-immune population, of approximately 850000 inhabitants, who are at risk of seasonal Plasmodium falciparum malaria. Malaria treatment in this area is usually only initiated on detection of malaria parasites in the peripheral bloodstream, as many other rickettsial and viral febrile illness mimic malaria. The malaria control programme traditionally relied on light microscopy of Giemsa-stained thick blood films for malaria diagnosis. This review summarizes operational research findings that led to the introduction of rapid malaria card tests for primary diagnosis of malaria throughout the Mpumalanga malaria area. Subsequent operational research and extensive experience over a four-year period since introducing the ICT Malaria Pf test appears to confirm the local appropriateness of this diagnostic modality. A laboratory is not required and clinic staff are empowered to make a prompt definitive diagnosis, limiting delays in initiating correct therapy. The simple, accurate and rapid non-microscopic means now available for diagnosing malaria could play an important role in Rolling Back Malaria in selected areas.
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Koepfli, Cristian; Barry, Alyssa; Javati, Sarah; Timinao, Lincoln; Nate, Elma; Mueller, Ivo; Barnadas, Celine
2014-01-01
Papua New Guinea (PNG) is undertaking intensified efforts to control malaria. The National Malaria Control Program aims to reduce the burden of disease by large-scale distribution of insecticide-treated bednets, improved diagnosis and implementation of new treatments. A scientific program monitoring the effect of these interventions, including molecular epidemiology studies, closely accompanies the program. Laboratory assays have been developed in (or transferred to) PNG to measure prevalence of infection and intensity of transmission as well as potential resistance to currently used drugs. These assays help to assess the impact of the National Malaria Control Program, and they reveal a much clearer picture of malaria epidemiology in PNG. In addition, analysis of the geographical clustering of parasites aids in selecting areas where intensified control will be most successful. This paper gives an overview of current research and recently completed studies in the molecular epidemiology of malaria conducted in Papua New Guinea.
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Wijesundere, Dilkushi Anula; Ramasamy, Ranjan
2017-01-01
Sri Lanka is a tropical island located South of India in the Indian Ocean. Malaria has been prevalent in the island for centuries but the country succeeded in eliminating the disease in 2013. Factors governing the past endemicity of malaria and its successful elimination from Sri Lanka in 2013 are analyzed. There is evidence that malaria might have been first introduced in the thirteenth century into a dry zone area with extensive irrigation works. Regular widespread epidemics of the disease have been documented in the twentieth century. The island nature of Sri Lanka, generally low transmission rates, widespread and accessible government hospitals and clinics that provide free and readily available diagnosis and treatment for malaria, adequate financial support and commitment to the Antimalaria Campaign (AMC), national and decentralized malaria control efforts sustained over a long period by dedicated and competent AMC staff, and the absence of zoonotic malaria are recognized as key factors responsible for eliminating malaria from Sri Lanka. These factors are analyzed in the context of their relevance to the present malaria elimination efforts in other countries with the overall aim of globally eradicating the disease. PMID:28894732
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Wijesundere, Dilkushi Anula; Ramasamy, Ranjan
2017-01-01
Sri Lanka is a tropical island located South of India in the Indian Ocean. Malaria has been prevalent in the island for centuries but the country succeeded in eliminating the disease in 2013. Factors governing the past endemicity of malaria and its successful elimination from Sri Lanka in 2013 are analyzed. There is evidence that malaria might have been first introduced in the thirteenth century into a dry zone area with extensive irrigation works. Regular widespread epidemics of the disease have been documented in the twentieth century. The island nature of Sri Lanka, generally low transmission rates, widespread and accessible government hospitals and clinics that provide free and readily available diagnosis and treatment for malaria, adequate financial support and commitment to the Antimalaria Campaign (AMC), national and decentralized malaria control efforts sustained over a long period by dedicated and competent AMC staff, and the absence of zoonotic malaria are recognized as key factors responsible for eliminating malaria from Sri Lanka. These factors are analyzed in the context of their relevance to the present malaria elimination efforts in other countries with the overall aim of globally eradicating the disease.
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Modeling the Cost Effectiveness of Malaria Control Interventions in the Highlands of Western Kenya
Stuckey, Erin M.; Stevenson, Jennifer; Galactionova, Katya; Baidjoe, Amrish Y.; Bousema, Teun; Odongo, Wycliffe; Kariuki, Simon; Drakeley, Chris; Smith, Thomas A.; Cox, Jonathan; Chitnis, Nakul
2014-01-01
Introduction Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal. Methods Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters. Results The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period. Conclusions All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria
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Modeling the cost effectiveness of malaria control interventions in the highlands of western Kenya.
Stuckey, Erin M; Stevenson, Jennifer; Galactionova, Katya; Baidjoe, Amrish Y; Bousema, Teun; Odongo, Wycliffe; Kariuki, Simon; Drakeley, Chris; Smith, Thomas A; Cox, Jonathan; Chitnis, Nakul
2014-01-01
Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal. Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters. The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period. All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria control program managers in the study area in
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Malaria control under unstable dynamics: reactive vs. climate-based strategies.
Baeza, Andres; Bouma, Menno J; Dhiman, Ramesh; Pascual, Mercedes
2014-01-01
In areas of the world where malaria prevails under unstable conditions, attacking the adult vector population through insecticide-based Indoor Residual Spraying (IRS) is the most common method for controlling epidemics. Defined in policy guidance, the use of Annual Parasitic Incidence (API) is an important tool for assessing the effectiveness of control and for planning new interventions. To investigate the consequences that a policy based on API in previous seasons might have on the population dynamics of the disease and on control itself in regions of low and seasonal transmission, we formulate a mathematical malaria model that couples epidemiologic and vector dynamics with IRS intervention. This model is parameterized for a low transmission and semi-arid region in northwest India, where epidemics are driven by high rainfall variability. We show that this type of feedback mechanism in control strategies can generate transient cycles in malaria even in the absence of environmental variability, and that this tendency to cycle can in turn limit the effectiveness of control in the presence of such variability. Specifically, for realistic rainfall conditions and over a range of control intensities, the effectiveness of such 'reactive' intervention is compared to that of an alternative strategy based on rainfall and therefore vector variability. Results show that the efficacy of intervention is strongly influenced by rainfall variability and the type of policy implemented. In particular, under an API 'reactive' policy, high vector populations can coincide more frequently with low control coverage, and in so doing generate large unexpected epidemics and decrease the likelihood of elimination. These results highlight the importance of incorporating information on climate variability, rather than previous incidence, in planning IRS interventions in regions of unstable malaria. These findings are discussed in the more general context of elimination and other low
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Vector control for malaria and other mosquito-borne diseases. Report of a WHO study group.
1995-01-01
Since the Ministerial Conference on Malaria in 1992, which acknowledged the urgent need for worldwide commitment to malaria control, efforts have been directed to implementation of a Global Malaria Control Strategy. Vector control, an essential component of malaria control, has become less effective in recent years, partly as a result of poor use of alternative control tools, inappropriate use of insecticides, lack of an epidemiological basis for interventions, inadequate resources and infrastructure, and weak management. Changing environmental conditions, the behavioural characteristics of certain vectors, and resistance to insecticides have added to the difficulties. This report of a WHO Study Group provides guidelines for the planning, implementation and evaluation of cost-effective and sustainable vector control in the context of the Global Malaria Control Strategy. It reviews the available methods - indoor residual spraying, personal protection, larval control and environmental management - stressing the need for selective and flexible use of interventions according to local conditions. Requirements for data collection and the appropriate use of entomological parameters and techniques are discussed and priorities identified for the development of local capacity for vector control and for operational research. Emphasis is placed both on the monitoring and evaluation of vector control to ensure cost-effectiveness and on the development of strong managerial structures, which can support community participation and intersectoral collaboration and accommodate the control of other vector-borne diseases. The report concludes with recommendations aimed at promoting the targeted and efficient use of vector control in preventing and controlling malaria, thereby reducing the threat to health and socioeconomic development in many tropical countries.
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Could Malaria Control Programmes be Timed to Coincide with Onset of Rainfall?
Komen, Kibii
2017-06-01
Malaria cases in South Africa's Northern Province of Limpopo have surpassed known endemic KwaZulu Natal and Mpumalanga Provinces. This paper applies statistical methods: regression analysis and impulse response function to understand the timing of impact and the length that such impacts last. Climate data (rainfall and temperature) are obtained from South African Weather Services (SAWs); global data from the European Centre for Medium-Range Weather Forecasts (ECMWF), while clinical malaria data came from Malaria Control Centre in Tzaneen (Limpopo Province). Data collected span from January 1998 to July 2007. Signs of the coefficients are positive for rainfall and temperature and negative for their exponents. Three out of five independent variables consistently maintain a very high statistical level of significance. The coefficients for climate variables describe an inverted u-shape: parameters for the exponents of rainfall (-0.02, -0.01, -0.02, -0.00) and temperature (-46.61, -47.46, -48.14, -36.04) are both negative. A one standard deviation rise in rainfall (rainfall onset) increases malaria cases, and the effects become sustained for at least 3 months and conclude that onset of rainfall therefore triggers a 'malaria season'. Malaria control programme and early warning system should be intensified in the first 3 months following the onset of rainfall.
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Malaria vaccines: looking back and lessons learnt
Lorenz, Veronique; Karanis, Panagiotis
2011-01-01
The current status of malaria vaccine approaches has the background of a long and arduous path of malaria disease control and vaccine development. Here, we critically review with regard to unilateral interventional approaches and highlight the impact of socioeconomic elements of malaria endemicity. The necessity of re-energizing basic research of malaria life-cycle and Plasmodium developmental biology to provide the basis for promising and cost-effective vaccine approaches and to reach eradication goals is more urgent than previously believed. We closely analyse the flaws of various vaccine approaches, outline future directions and challenges that still face us and conclude that the focus of the field must be shifted to the basic research efforts including findings on the skin stage of infection. We also reflect on economic factors of vaccine development and the impact of public perception when it comes to vaccine uptake. PMID:23569729
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Infectivity of Chronic Malaria Infections and Its Consequences for Control and Elimination.
Aguas, Ricardo; Maude, Richard J; Gomes, M Gabriela M; White, Lisa J; White, Nicholas J; Dondorp, Arjen M
2018-05-10
Assessing the importance of targeting the chronic Plasmodium falciparum malaria reservoir is pivotal as the world moves toward malaria eradication. Through the lens of a mathematical model, we show how, for a given malaria prevalence, the relative infectivity of chronic individuals determines what intervention tools are predicted be the most effective. Crucially, in a large part of the parameter space where elimination is theoretically possible, it can be achieved solely through improved case management. However, there are a significant number of settings where malaria elimination requires not only good vector control but also a mass drug administration campaign. Quantifying the relative infectiousness of chronic malaria across a range of epidemiological settings would provide essential information for the design of effective malaria elimination strategies. Given the difficulties obtaining this information, we also provide a set of epidemiological metrics that can be used to guide policy in the absence of such data.
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Wang, Ru-Bo; Dong, Jia-Qiang; Xia, Zhi-Gui; Cai, Tao; Zhang, Qing-Feng; Zhang, Yao; Tian, Yang-Hui; Sun, Xiao-Ying; Zhang, Guang-Yun; Li, Qing-Pu; Xu, Xiao-Yu; Li, Jia-Yin; Zhang, Jun
2016-10-06
For many countries where malaria is endemic, the burden of malaria is high in border regions. In ethnic minority areas along the Myanmar-China border, residents have poor access to medical care for diagnosis and treatment, and there have been many malaria outbreaks in such areas. Since 2007, with the support of the Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM), a malaria control project was introduced to reduce the malaria burden in several ethnic minority regions. A malaria control network was established during the period from 2007 to 2014. Multiple malaria interventions, including diagnosis, treatment, distribution of LLINs and health education, were conducted to improve the accessibility and quality of malaria control services for local residents. Annual cross-sectional surveys were conducted to evaluate intervention coverage and indicators of malaria transmission. In ethnic minority regions where a malaria control network was established, both the annual malaria incidence (19.1 per thousand per year, in 2009; 8.7, in 2014) and malaria prevalence (13.6 % in 2008; 0.43 % in 2014) decreased dramatically during the past 5-6 years. A total of 851 393 febrile patients were detected, 202 598 malaria cases (including confirmed cases and suspected cases) were treated, and 759 574 LLINs were delivered to populations at risk. Of households in 2012, 73.9 % had at least one ITNs/LLINs (vs. 28.3 %, in 2008), and 50.7 % of children less than 5 years and 50.3 % of pregnant women slept under LLINs the night prior to their visit. Additionally, malaria knowledge was improved in 68.4 % of residents. There has been great success in improving malaria control in these regions from 2007 to 2014. Malaria burdens have decreased, especially in KOK and WA. The continued maintenance of sustainable malaria control networks in these regions may be a long-term process, due to regional conflicts and the lack of funds, technology, and health workers. Furthermore
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Sociodemographic Determinants of Malaria among Under-Five Children in Ghana.
Nyarko, Samuel Harrenson; Cobblah, Anastasia
2014-01-01
Background. Malaria is an entrenched global health challenge particularly in the sub-Saharan African countries. However, in Ghana, little is known about the determinants of malaria prevalence among under-five children. As such, this study sought to examine the sociodemographic factors that determine malaria among under-five children in Ghana. Methods. This paper used secondary data drawn from the 2008 Ghana Demographic and Health Survey. Bivariate analysis and complementary log-log regression models were used to examine the determinants of malaria prevalence among under-five children in Ghana for the study period. Results. The results therefore revealed that region of residence, age of child, and ownership of mosquito net were the key predictors of malaria cases among under-five children in Ghana for the five-year period preceding the survey. Conclusion. It is therefore imperative that special education on prevention of malaria should be intensified by the National Malaria Control Programme in all the regions in order to reduce malaria prevalence particularly among under-five children in Ghana.
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2011-01-01
Background In Ethiopia, malaria transmission is seasonal and unstable, with both Plasmodium falciparum and Plasmodium vivax endemic. Such spatial and temporal clustering of malaria only serves to underscore the importance of regularly collecting up-to-date malaria surveillance data to inform decision-making in malaria control. Cross-sectional school-based malaria surveys were conducted across Oromia Regional State to generate up-to-date data for planning malaria control interventions, as well as monitoring and evaluation of operational programme implementation. Methods Two hundred primary schools were randomly selected using a stratified and weighted sampling frame; 100 children aged five to 18 years were then randomly chosen within each school. Surveys were carried out in May 2009 and from October to December 2009, to coincide with the peak of malaria transmission in different parts of Oromia. Each child was tested for malaria by expert microscopy, their haemoglobin measured and a simple questionnaire completed. Satellite-derived environmental data were used to assess ecological correlates of Plasmodium infection; Bayesian geostatistical methods and Kulldorff's spatial scan statistic were employed to investigate spatial heterogeneity. Results A total 20,899 children from 197 schools provided blood samples, two selected schools were inaccessible and one school refused to participate. The overall prevalence of Plasmodium infection was found to be 0.56% (95% CI: 0.46-0.67%), with 53% of infections due to P. falciparum and 47% due to P. vivax. Of children surveyed, 17.6% (95% CI: 17.0-18.1%) were anaemic, while 46% reported sleeping under a mosquito net the previous night. Malaria was found at 30 (15%) schools to a maximum elevation of 2,187 metres, with school-level Plasmodium prevalence ranging between 0% and 14.5%. Although environmental variables were only weakly associated with P. falciparum and P. vivax infection, clusters of infection were identified within
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Eskenazi, Brenda; Quirós-Alcalá, Lesliam; Lipsitt, Jonah M; Wu, Lemuel D; Kruger, Philip; Ntimbane, Tzundzukani; Nawn, John Burns; Bornman, M S Riana; Seto, Edmund
2014-07-01
Recent estimates indicate that malaria has led to over half a million deaths worldwide, mostly to African children. Indoor residual spraying (IRS) of insecticides is one of the primary vector control interventions. However, current reporting systems do not obtain precise location of IRS events in relation to malaria cases, which poses challenges for effective and efficient malaria control. This information is also critical to avoid unnecessary human exposure to IRS insecticides. We developed and piloted a mobile-based application (mSpray) to collect comprehensive information on IRS spray events. We assessed the utility, acceptability and feasibility of using mSpray to gather improved homestead- and chemical-level IRS coverage data. We installed mSpray on 10 cell phones with data bundles, and pilot tested it with 13 users in Limpopo, South Africa. Users completed basic information (number of rooms/shelters sprayed; chemical used, etc.) on spray events. Upon submission, this information as well as geographic positioning system coordinates and time/date stamp were uploaded to a Google Drive Spreadsheet to be viewed in real time. We administered questionnaires, conducted focus groups, and interviewed key informants to evaluate the utility of the app. The low-cost, cell phone-based "mSpray" app was learned quickly by users, well accepted and preferred to the current paper-based method. We recorded 2865 entries (99.1% had a GPS accuracy of 20 m or less) and identified areas of improvement including increased battery life. We also identified a number of logistic and user problems (e.g., cost of cell phones and cellular bundles, battery life, obtaining accurate GPS measures, user errors, etc.) that would need to be overcome before full deployment. Use of cell phone technology could increase the efficiency of IRS malaria control efforts by mapping spray events in relation to malaria cases, resulting in more judicious use of chemicals that are potentially harmful to humans
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Eskenazi, Brenda; Quirós-Alcalá, Lesliam; Lipsitt, Jonah M.; Wu, Lemuel D.; Kruger, Philip; Ntimbane, Tzundzukani; Nawn, John Burns; Bornman, M. S. Riana; Seto, Edmund
2015-01-01
Recent estimates indicate that malaria has led to over half a million deaths worldwide, mostly to African children. Indoor residual spraying (IRS) of insecticides is one of the primary vector control interventions. However, current reporting systems do not obtain precise location of IRS events in relation to malaria cases, which poses challenges for effective and efficient malaria control. This information is also critical to avoid unnecessary human exposure to IRS insecticides. We developed and piloted a mobile-based application (mSpray) to collect comprehensive information on IRS spray events. We assessed the utility, acceptability and feasibility of using mSpray to gather improved homestead- and chemical-level IRS coverage data. We installed mSpray on 10 cell phones with data bundles, and pilot tested it with 13 users in Limpopo, South Africa. Users completed basic information (number of rooms/shelters sprayed; chemical used, etc.) on spray events. Upon submission, this information as well as geographic positioning system coordinates and time/date stamp were uploaded to a Google Drive Spreadsheet to be viewed in real time. We administered questionnaires, conducted focus groups, and interviewed key informants to evaluate the utility of the app. The low-cost, cell phone-based “mSpray” app was learned quickly by users, well accepted and preferred to the current paper-based method. We recorded 2,865 entries (99.1% had a GPS accuracy of 20 m or less) and identified areas of improvement including increased battery life. We also identified a number of logistic and user problems (e.g., cost of cell phones and cellular bundles, battery life, obtaining accurate GPS measures, user errors, etc.) that would need to be overcome before full deployment. Use of cell phone technology could increase the efficiency of IRS malaria control efforts by mapping spray events in relation to malaria cases, resulting in more judicious use of chemicals that are potentially harmful to
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Lell, Bertrand; Mordmüller, Benjamin; Dejon Agobe, Jean-Claude; Honkpehedji, Josiane; Zinsou, Jeannot; Mengue, Juliana Boex; Loembe, Marguerite Massinga; Adegnika, Ayola Akim; Held, Jana; Lalremruata, Albert; Nguyen, The Trong; Esen, Meral; Kc, Natasha; Ruben, Adam J; Chakravarty, Sumana; Lee Sim, B Kim; Billingsley, Peter F; James, Eric R; Richie, Thomas L; Hoffman, Stephen L; Kremsner, Peter G
2018-02-01
Controlled human malaria infection (CHMI) by direct venous inoculation (DVI) with 3,200 cryopreserved Plasmodium falciparum sporozoites (PfSPZ) consistently leads to parasitemia and malaria symptoms in malaria-naive adults. We used CHMI by DVI to investigate infection rates, parasite kinetics, and malaria symptoms in lifelong malaria-exposed (semi-immune) Gabonese adults with and without sickle cell trait. Eleven semi-immune Gabonese with normal hemoglobin (IA), nine with sickle cell trait (IS), and five nonimmune European controls with normal hemoglobin (NI) received 3,200 PfSPZ by DVI and were followed 28 days for parasitemia by thick blood smear (TBS) and quantitative polymerase chain reaction (qPCR) and for malaria symptoms. End points were time to parasitemia and parasitemia plus symptoms. PfSPZ Challenge was well tolerated and safe. Five of the five (100%) NI, 7/11 (64%) IA, and 5/9 (56%) IS volunteers developed parasitemia by TBS, and 5/5 (100%) NI, 9/11 (82%) IA, and 7/9 (78%) IS by qPCR, respectively. The time to parasitemia by TBS was longer in IA (geometric mean 16.9 days) and IS (19.1 days) than in NA (12.6 days) volunteers ( P = 0.016, 0.021, respectively). Five of the five, 6/9, and 1/7 volunteers with parasitemia developed symptoms ( P = 0.003, NI versus IS). Naturally adaptive immunity (NAI) to malaria significantly prolonged the time to parasitemia. Sickle cell trait seemed to prolong it further. NAI plus sickle cell trait, but not NAI alone, significantly reduced symptom rate. Twenty percent (4/20) semi-immunes demonstrated sterile protective immunity. Standardized CHMI with PfSPZ Challenge is a powerful tool for dissecting the impact of innate and naturally acquired adaptive immunity on malaria.
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Keys to success for a school-based malaria control program in primary schools in Thailand.
Okabayashi, Hironori; Thongthien, Pimpimon; Singhasvanon, Pratap; Waikagul, Jitra; Looareesuwan, Sornchai; Jimba, Masamine; Kano, Shigeyuki; Kojima, Somei; Takeuchi, Tsutomu; Kobayashi, Jun; Tateno, Seiki
2006-06-01
School-based malaria control has been recognized as a new approach for the control of this disease in the Greater Mekong Subregion since 2000. We evaluated a school-based malaria control program near the western border of Thailand using a before-after intervention study. The major intervention activities included teacher training with specialized malaria teaching materials and participatory learning methods. The target population was 17 school principals, 111 teachers and 852 schoolchildren of grade 3, 4, and 5 in 17 schools. After the intervention, the teachers taught about malaria more actively than before. The teachers who could design a lesson plan on malaria increased from 30.7% to 47.7% (p=0.015) and the teachers who had taught about malaria increased from 71.9% to 84.3% (p=0.035). As a result of the program, the schoolchildren changed their behavior positively towards malaria prevention with significant difference in 6 of 7 questions. For example, the schoolchildren 'who always took care of mosquito bites' increased from 42.7% to 62.1% (p<0.001) and the schoolchildren 'who always reported their parents or teachers when they had fever' increased from 36.0% to 56.0% (p<0.001). In conclusion, the keys to a successful intervention lie in good teaching materials and a participatory approach utilizing the well-established Thailand's school health system. Beyond Thailand, school-based malaria control could be applied to other Greater Mekong Subregion countries with careful analysis of school health context in each country.
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[Application of health education of house-to-house visit in malaria prevention and control].
Zhou, Wen-gang; Qu, Yan; Wang, Wen-guang; Tang, Song-yuan
2014-10-01
To evaluate the effects of health education of house-to-house visit in malaria prevention and control in the border and minority areas. A health education of house-to-house visit in malaria prevention and control was carried out, and baseline and follow up surveys were conducted by qualitative and quantitative methods to document the changes of local villagers' knowledge, attitudes and behaviors (KAP) of malaria prevention and control in 2 counties of Yunnan Province, and the results before and after the interventions were analyzed and compared. After the intervention, the cognition rates about malaria symptoms and signs, transmission mode, preventive measures and health-seeking behaviors were 99.3%, 98.9%, 79.9% and 99.3% respectively in the local residents, and those were 39.2%, 8.2%, 47.0% and 49.9% respectively before the intervention, and all the differences were statistically significant (P all < 0.01). KAP related to malaria among the targeting population has improved after the interventions and the house-to-house visit is an effective community-based health education approach.
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Dako-Gyeke, Mavis; Kofie, Humphrey M
2015-03-01
Throughout Africa and particularly in Ghana, there are concerns about malaria infection during pregnancy. This study aimed to investigate factors that influence malaria prevention and control practices among pregnant women residing in Chorkor and Korle-Gonno in Accra, Ghana. One hundred and twenty pregnant women between ages 18-49 were randomly recruited during antenatal sessions at a maternity facility in Accra, as participants for the study. An interviewer-administered questionnaire was used to collect data, which were analysed using SPSS version16.0. It was found that in Chorkor and Korle-Gonno, 57.4% and 42.6% participants respectively reported having been infected with malaria during their current pregnancy. There was no significant relationship between religious beliefs of participants and their malaria prevention and control practices (X2 = 0.28, P = .53). However, there was a significant relationship between malaria prevention and control practices of participants and their income earning (X2 = 53.94, P = .00) and employment (X2 = 61.76, P = .00) statuses. With the exception of ethnicity (X2 = 35.62, P =.22), other socio-cultural conditions had a significant relationship with malaria prevention and control practices of the participants. The findings suggest the need to consider and integrate factors, such as poverty and poor living conditions in malaria prevention and control strategies.
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Howes, Rosalind E; Mioramalala, Sedera Aurélien; Ramiranirina, Brune; Franchard, Thierry; Rakotorahalahy, Andry Joeliarijaona; Bisanzio, Donal; Gething, Peter W; Zimmerman, Peter A; Ratsimbasoa, Arsène
2016-10-18
Malaria remains a major public health problem in Madagascar. Widespread scale-up of intervention coverage has led to substantial reductions in case numbers since 2000. However, political instability since 2009 has disrupted these efforts, and a resurgence of malaria has since followed. This paper re-visits the sub-national stratification of malaria transmission across Madagascar to propose a contemporary update, and evaluates the reported routine case data reported at this sub-national scale. Two independent malariometrics were evaluated to re-examine the status of malaria across Madagascar. First, modelled maps of Plasmodium falciparum infection prevalence (PfPR) from the Malaria Atlas Project were used to update the sub-national stratification into 'ecozones' based on transmission intensity. Second, routine reports of case data from health facilities were synthesized from 2010 to 2015 to compare the sub-national epidemiology across the updated ecozones over time. Proxy indicators of data completeness are investigated. The epidemiology of malaria is highly diverse across the island's ecological regions, with eight contiguous ecozones emerging from the transmission intensity PfPR map. East and west coastal areas have highest transmission year-round, contrasting with the central highlands and desert south where trends appear more closely associated with epidemic outbreak events. Ecozones have shown steady increases in reported malaria cases since 2010, with a near doubling of raw reported case numbers from 2014 to 2015. Gauges of data completeness suggest that interpretation of raw reported case numbers will underestimate true caseload as only approximately 60-75 % of health facility data are reported to the central level each month. A sub-national perspective is essential when monitoring the epidemiology of malaria in Madagascar and assessing local control needs. A robust assessment of the status of malaria at a time when intervention coverage efforts are being
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Synergistic and antagonistic interactions between bednets and vaccines in the control of malaria.
Artzy-Randrup, Yael; Dobson, Andrew P; Pascual, Mercedes
2015-03-10
It is extremely likely that the malaria vaccines currently in development will be used in conjunction with treated bednets and other forms of malaria control. The interaction of different intervention methods is at present poorly understood in a disease such as malaria where immunity is more complex than for other pathogens that have been successfully controlled by vaccination. Here we develop a general mathematical model of malaria transmission to examine the interaction between vaccination and bednets. Counterintuitively, we find that the frailty of malaria immunity will potentially cause both synergistic and antagonistic interactions between vaccination and the use of bednets. We explore the conditions that create these tensions, and outline strategies that minimize their detrimental impact. Our analysis specifically considers the three leading vaccine classes currently in development: preerythrocytic (PEV), blood stage (BSV), and transmission blocking (TBV). We find that the combination of BSV with treated bednets can lead to increased morbidity with no added value in terms of elimination; the interaction is clearly antagonistic. In contrast, there is strong synergy between PEV and treated bednets that may facilitate elimination, although transient stages are likely to increase morbidity. The combination of TBV with treated bednets is synergistic, lowering both morbidity and elimination thresholds. Our results suggest that vaccines will not provide a straightforward solution to malaria control, and that future programs need to consider the synergistic and antagonistic interactions between vaccines and treated bednets.
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Sun, Jun-Ling; Zhou, Sheng; Geng, Qi-Bin; Zhang, Qian; Zhang, Zi-Ke; Zheng, Can-Jun; Hu, Wen-Biao; Clements, Archie C A; Lai, Sheng-Jie; Li, Zhong-Jie
2016-06-27
The elimination of malaria requires high-quality surveillance data to enable rapid detection and response to individual cases. Evaluation of the performance of a national malaria surveillance system could identify shortcomings which, if addressed, will improve the surveillance program for malaria elimination. Case-level data for the period 2005-2014 were extracted from the China National Notifiable Infectious Disease Reporting Information System and Malaria Enhanced Surveillance Information System. The occurrence of cases, accuracy and timeliness of case diagnosis, reporting and investigation, were assessed and compared between the malaria control stage (2005-2010) and elimination stage (2011-2014) in mainland China. A total of 210 730 malaria cases were reported in mainland China in 2005-2014. The average annual incidence declined dramatically from 2.5 per 100 000 people at the control stage to 0.2 per 100 000 at the elimination stage, but the proportion of migrant cases increased from 9.8 % to 41.0 %. Since the initiation of the National Malaria Elimination Programme in 2010, the overall proportion of cases diagnosed by laboratory testing consistently improved, with the highest of 99.0 % in 2014. However, this proportion was significantly lower in non-endemic provinces (79.0 %) than that in endemic provinces (91.4 %) during 2011-2014. The median interval from illness onset to diagnosis was 3 days at the elimination stage, with one day earlier than that at the control stage. Since 2011, more than 99 % cases were reported within 1 day after being diagnosed, while the proportion of cases that were reported within one day after diagnosis was lowest in Tibet (37.5 %). The predominant source of cases reporting shifted from town-level hospitals at the control stage (67.9 % cases) to city-level hospitals and public health institutes at the eliminate stage (69.4 % cases). The proportion of investigation within 3 days after case reporting has improved, from 74
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Comfort, Alison B.; van Dijk, Janneke H.; Mharakurwa, Sungano; Stillman, Kathryn; Gabert, Rose; Korde, Sonali; Nachbar, Nancy; Derriennic, Yann; Musau, Stephen; Hamazakaza, Petan; Zyambo, Khozya D.; Zyongwe, Nancy M.; Hamainza, Busiku; Thuma, Philip E.
2014-01-01
There is little evidence on the impact of malaria control on the health system, particularly at the facility level. Using retrospective, longitudinal facility-level and patient record data from two hospitals in Zambia, we report a pre-post comparison of hospital admissions and outpatient visits for malaria and estimated costs incurred for malaria admissions before and after malaria control scale-up. The results show a substantial reduction in inpatient admissions and outpatient visits for malaria at both hospitals after the scale-up, and malaria cases accounted for a smaller proportion of total hospital visits over time. Hospital spending on malaria admissions also decreased. In one hospital, malaria accounted for 11% of total hospital spending before large-scale malaria control compared with < 1% after malaria control. The findings demonstrate that facility-level resources are freed up as malaria is controlled, potentially making these resources available for other diseases and conditions. PMID:24218409
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Spatial and temporal distribution of falciparum malaria in China
Lin, Hualiang; Lu, Liang; Tian, Linwei; Zhou, Shuisen; Wu, Haixia; Bi, Yan; Ho, Suzanne C; Liu, Qiyong
2009-01-01
Background Falciparum malaria is the most deadly among the four main types of human malaria. Although great success has been achieved since the launch of the National Malaria Control Programme in 1955, malaria remains a serious public health problem in China. This paper aimed to analyse the geographic distribution, demographic patterns and time trends of falciparum malaria in China. Methods The annual numbers of falciparum malaria cases during 1992–2003 and the individual case reports of each clinical falciparum malaria during 2004–2005 were extracted from communicable disease information systems in China Center for Diseases Control and Prevention. The annual number of cases and the annual incidence were mapped by matching them to corresponding province- and county-level administrative units in a geographic information system. The distribution of falciparum malaria by age, gender and origin of infection was analysed. Time-series analysis was conducted to investigate the relationship between the falciparum malaria in the endemic provinces and the imported falciparum malaria in non-endemic provinces. Results Falciparum malaria was endemic in two provinces of China during 2004–05. Imported malaria was reported in 26 non-endemic provinces. Annual incidence of falciparum malaria was mapped at county level in the two endemic provinces of China: Yunnan and Hainan. The sex ratio (male vs. female) for the number of cases in Yunnan was 1.6 in the children of 0–15 years and it reached 5.7 in the adults over 15 years of age. The number of malaria cases in Yunnan was positively correlated with the imported malaria of concurrent months in the non-endemic provinces. Conclusion The endemic area of falciparum malaria in China has remained restricted to two provinces, Yunnan and Hainan. Stable transmission occurs in the bordering region of Yunnan and the hilly-forested south of Hainan. The age and gender distribution in the endemic area is characterized by the predominance
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Control of malaria in the Comoro Islands over the past century.
Chakir, Ismaël; Said, Ali Ibrahim; Affane, Bacar; Jambou, Ronan
2017-09-26
The Comoros are an archipelago located in the Indian Ocean between the eastern coasts of Africa and north of Madagascar. Malaria transmission appeared late in the 19th century due to the intensification of human migration. The story of malaria transmission for the past century is depicted to provide useful lessons for the future. Currently, malaria transmission occurs differently on each island; thus, control strategies must be adapted for each particular island. Tentative malaria control in Comoros has a long history of success and failure. This study reviews the data available as a basis for recommendations for the future. There has been much effort to reach a pre-eradication state in Anjouan and Moheli, but only control steps have been taken in the Great Comoro. To date, the primary strategy used is mass treatment of the population using artemisinin-based combination therapy (ACT), which is similar to the strategy deployed during the 1950s in other countries. ACT appears efficient in two of the three islands; however, the sustainability of the strategy is unknown. This sustainability is compromised by (i) the huge level of uncontrolled exchange between the Comoro Islands and their neighbours, increasing the risk of introducing ACT-resistant strains, (ii) the use of large quantities of pesticides for agriculture usually associated with the resistance of mosquitoes, and (iii) the cost of the actions themselves. In view of the history of malaria in this area, the first recommendation is to enhance the training of health workers and the population. The second step is to establish a national strategy to assess malaria and related factors, which is currently lacking. A survey to assess the drug sensitivity of the parasites is particularly important in a context of low transmission associated with mass treatment of the population. The last point should be to secure financial support, which is not obvious in a context of pre-elimination. The Comoro Islands are thus a
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Financial management systems under decentralization and their effect on malaria control in Uganda.
Kivumbi, George W; Nangendo, Florence; Ndyabahika, Boniface Rutagira
2004-01-01
A descriptive case study with multiple sites and a single level of analysis was carried out in four purposefully selected administrative districts of Uganda to investigate the effect of financial management systems under decentralization on malaria control. Data were primarily collected from 36 interviews with district managers, staff at health units and local leaders. A review of records and documents related to decentralization at the central and district level was also used to generate data for the study. We found that a long, tedious, and bureaucratic process combined with lack of knowledge in working with new financial systems by several actors characterized financial flow under decentralization. This affected the timely use of financial resources for malaria control in that there were funds in the system that could not be accessed for use. We were also told that sometimes these funds were returned to the central government because of non-use due to difficulties in accessing them and/or stringent conditions not to divert them to other uses. Our data showed that a cocktail of bureaucratic control systems, corruption and incompetence make the financial management system under decentralization counter-productive for malaria control. The main conclusion is that good governance through appropriate and efficient financial management systems is very important for effective malaria control under decentralization.
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Knowledge, attitudes and practices of malaria in Colombia
2014-01-01
Background Although Colombia has witnessed an important decrease in malaria transmission, the disease remains a public health problem with an estimated ~10 million people currently living in areas with malaria risk and ~61,000 cases reported in 2012. This study aimed to determine and compare the level of knowledge, attitudes and practices (KAP) about malaria in three endemic communities of Colombia to provide the knowledge framework for development of new intervention strategies for malaria elimination. Methods A cross-sectional KAP survey was conducted in the municipalities of Tierralta, Buenaventura and Tumaco, categorized according to high risk (HR) and moderate risk (MR) based on the annual parasite index (API). Surveys were managed using REDCap and analysed using MATLAB and GraphPad Prism. Results A total of 267 residents, mostly women (74%) were surveyed. Although no differences were observed on the knowledge of classical malaria symptoms between HR and MR regions, significant differences were found in knowledge and attitudes about transmission mechanisms, anti-malarial use and malaria diagnosis. Most responders in both regions (93.5% in MR, and 94.3% in HR areas) indicated use of insecticide-treated nets (ITNs) to protect themselves from malaria, and 75.5% of responders in HR indicated they did nothing to prevent malaria transmission outdoors. Despite a high level of knowledge in the study regions, significant gaps persisted relating to practices. Self-medication and poor adherence to treatment, as well as lack of both indoor and outdoor vector control measures, were significantly associated with higher malaria risk. Conclusions Although significant efforts are currently being made by the Ministry of Health to use community education as one of the main components of the control strategy, these generic education programmes may not be applicable to all endemic regions of Colombia given the substantial geographic, ethnic and cultural diversity. PMID:24885909
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Cahyaningrum, Pratiwi; Sulistyawati, Sulistyawati
2018-05-01
Malaria remains a public health concern worldwide, including Indonesia. Purworejo is a district in which endemic of malaria, they have re-setup to entering malaria elimination in 2021. Accordingly, actions must be taken to accelerate and guaranty that the goal will reach based on an understanding of the risk factors for malaria. Thus, we analysed malaria risk factors based on human and housing conditions in Kaligesing, Purworejo, Indonesia. A case-control study was carried out in Kaligesing subdistrict, Purworejo, Indonesia in July to August 2017. A structured questionnaire and checklist were used to collect data from 96 participants, who consisted of 48 controls and 48 cases. Univariate, bivariate, and multivariate analyses were performed. Bivariate analysis found that education level, the presence of a cattle cage within 100 m of the house, not sleeping under a bednet the previous night, and not closing the doors and windows from 6 p.m. to 5 a.m. were significantly ( p ≤0.25) associated with malaria. Of these factors, only not sleeping under a bednet the previous night and not closing the doors and windows from 6 p.m. to 5 a.m. were significantly associated with malaria. The findings of this study demonstrate that potential risk factor for Malaria should be paid of attention all the time, particularly for an area which is targeting Malaria elimination.
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Kobylinski, Kevin C.; Alout, Haoues; Foy, Brian D.; Clements, Archie; Adisakwattana, Poom; Swierczewski, Brett E.; Richardson, Jason H.
2014-01-01
Recently there have been calls for the eradication of malaria and the elimination of soil-transmitted helminths (STHs). Malaria and STHs overlap in distribution, and STH infections are associated with increased risk for malaria. Indeed, there is evidence that suggests that STH infection may facilitate malaria transmission. Malaria and STH coinfection may exacerbate anemia, especially in pregnant women, leading to worsened child development and more adverse pregnancy outcomes than these diseases would cause on their own. Ivermectin mass drug administration (MDA) to humans for malaria parasite transmission suppression is being investigated as a potential malaria elimination tool. Adding albendazole to ivermectin MDAs would maximize effects against STHs. A proactive, integrated control platform that targets malaria and STHs would be extremely cost-effective and simultaneously reduce human suffering caused by multiple diseases. This paper outlines the benefits of adding albendazole to ivermectin MDAs for malaria parasite transmission suppression. PMID:25070998
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Mobile phones improve case detection and management of malaria in rural Bangladesh
2013-01-01
Background The recent introduction of mobile phones into the rural Bandarban district of Bangladesh provided a resource to improve case detection and treatment of patients with malaria. Methods During studies to define the epidemiology of malaria in villages in south-eastern Bangladesh, an area with hypoendemic malaria, the project recorded 986 mobile phone calls from families because of illness suspected to be malaria between June 2010 and June 2012. Results Based on phone calls, field workers visited the homes with ill persons, and collected blood samples for malaria on 1,046 people. 265 (25%) of the patients tested were positive for malaria. Of the 509 symptomatic malaria cases diagnosed during this study period, 265 (52%) were detected because of an initial mobile phone call. Conclusion Mobile phone technology was found to be an efficient and effective method for rapidly detecting and treating patients with malaria in this remote area. This technology, when combined with local knowledge and field support, may be applicable to other hard-to-reach areas to improve malaria control. PMID:23374585
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Would the control of invasive alien plants reduce malaria transmission? A review.
Stone, Christopher M; Witt, Arne B R; Walsh, Guillermo Cabrera; Foster, Woodbridge A; Murphy, Sean T
2018-02-01
Vector control has been the most effective preventive measure against malaria and other vector-borne diseases. However, due to concerns such as insecticide resistance and budget shortfalls, an integrated control approach will be required to ensure sustainable, long-term effectiveness. An integrated management strategy should entail some aspects of environmental management, relying on coordination between various scientific disciplines. Here, we review one such environmental control tactic: invasive alien plant management. This covers salient plant-mosquito interactions for both terrestrial and aquatic invasive plants and how these affect a vector's ability to transmit malaria. Invasive plants tend to have longer flowering durations, more vigorous growth, and their spread can result in an increase in biomass, particularly in areas where previously little vegetation existed. Some invasive alien plants provide shelter or resting sites for adult mosquitoes and are also attractive nectar-producing hosts, enhancing their vectorial capacity. We conclude that these plants may increase malaria transmission rates in certain environments, though many questions still need to be answered, to determine how often this conclusion holds. However, in the case of aquatic invasive plants, available evidence suggests that the management of these plants would contribute to malaria control. We also examine and review the opportunities for large-scale invasive alien plant management, including options for biological control. Finally, we highlight the research priorities that must be addressed in order to ensure that integrated vector and invasive alien plant management operate in a synergistic fashion.
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Haque, Ubydul; Overgaard, Hans J; Clements, Archie C A; Norris, Douglas E; Islam, Nazrul; Karim, Jahirul; Roy, Shyamal; Haque, Waziul; Kabir, Moktadir; Smith, David L; Glass, Gregory E
2014-02-01
Malaria is endemic in 13 of 64 districts in Bangladesh. About 14 million people are at risk. Some evidence suggests that the prevalence of malaria in Bangladesh has decreased since the the Global Fund to Fight AIDS, Tuberculosis and Malaria started to support the National Malaria Control Program (NMCP) in 2007. We did an epidemiological and economic assessment of malaria control in Bangladesh. We obtained annually reported, district-level aggregated malaria case data and information about disbursed funds from the NMCP. We used a Poisson regression model to examine the associations between total malaria, severe malaria, malaria-attributable mortality, and insecticide-treated net coverage. We identified and mapped malaria hotspots using the Getis-Ord Gi* statistic. We estimated the cost-effectiveness of the NMCP by estimating the cost per confirmed case, cost per treated case, and cost per person of insecticide-treated net coverage. During the study period (from Jan 1, 2008, to Dec 31, 2012) there were 285,731 confirmed malaria cases. Malaria decreased from 6.2 cases per 1000 population in 2008, to 2.1 cases per 1000 population in 2012. Prevalence of all malaria decreased by 65% (95% CI 65-66), severe malaria decreased by 79% (78-80), and malaria-associated mortality decreased by 91% (83-95). By 2012, there was one insecticide-treated net for every 2.6 individuals (SD 0.20). Districts with more than 0.5 insecticide-treated nets per person had a decrease in prevalence of 21% (95% CI 19-23) for all malaria, 25% (17-32) for severe malaria, and 76% (35-91) for malaria-associated mortality among all age groups. Malaria hotspots remained in the highly endemic districts in the Chittagong Hill Tracts. The cost per diagnosed case was US$0.39 (SD 0.02) and per treated case was $0.51 (0.27); $0.05 (0.04) was invested per person per year for health education and $0.68 (0.30) was spent per person per year for insecticide-treated net coverage. Malaria elimination is an achievable
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Msyamboza, K; Senga, E; Tetteh-Ashong, E; Kazembe, P; Brabin, B J
2007-04-01
The evaluation of the effectiveness of antimalarial drugs and bed net use in pregnant women is an important aspect of monitoring and surveillance of malaria control in pregnancy. In principle the screening method for assessing vaccine efficacy can be applied in non-vaccine settings for assessing interventions for malaria control in pregnancy. In this analysis field data on the proportion of placental malaria cases treated with two doses of sulphadoxine-pyrimethamine (SP) and the uptake of two doses of SP in the antenatal clinic was used in a case-coverage method to assess the protective effectiveness (PE) of intermittent preventive treatment with SP for malaria control in pregnancy. PE was assessed using placental malaria, low birthweight and maternal anaemia at delivery as outcome variables. The method was also applied to an evaluation of the protective effectiveness of self-reported use of impregnated bed nets (ITNs). Effectiveness was highest for reduction of low birthweight in multigravidae (87.2%, 95% CI, 83.2-91.3%). PE was lower for placental malaria (61.6% primigravidae, 28.5% multigravidae), and maternal anaemia (Hb < 8.0 g/dl, 37.8% primigravidae, 29.6% multigravidae). Estimates for PE of self-reported use of ITNs gave values for all three outcome parameters that were much lower than for SP use. For women of all parties effectiveness estimates for reduction of low birthweight were 22% (95% CI, 17.7-26.4), prevention of placental malaria (all types) 7.1% (95% CI, 4.4-9.8), prevention of active placental infection 38.9% (95% CI, 27.4-50.4), and for maternal anaemia 8.8% (95% CI, 0-20.0). The case-coverage method could provide a useful and practical approach to routine monitoring and evaluation of drug interventions to control malaria in pregnancy and has potentially wide applications. Effectiveness estimates related to reported ITN use in pregnancy may be less reliable. The method should be further evaluated using currently available data sets.
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Maude, Richard J.; Silamut, Kamolrat; Plewes, Katherine; Charunwatthana, Prakaykaew; Ho, May; Abul Faiz, M.; Rahman, Ridwanur; Hossain, Md Amir; Hassan, Mahtab U.; Bin Yunus, Emran; Hoque, Gofranul; Islam, Faridul; Ghose, Aniruddha; Hanson, Josh; Schlatter, Joel; Lacey, Rachel; Eastaugh, Alison; Tarning, Joel; Lee, Sue J.; White, Nicholas J.; Chotivanich, Kesinee; Day, Nicholas P. J.; Dondorp, Arjen M.
2014-01-01
Background. Cytoadherence and sequestration of erythrocytes containing mature stages of Plasmodium falciparum are central to the pathogenesis of severe malaria. The oral anthelminthic drug levamisole inhibits cytoadherence in vitro and reduces sequestration of late-stage parasites in uncomplicated falciparum malaria treated with quinine. Methods. Fifty-six adult patients with severe malaria and high parasitemia admitted to a referral hospital in Bangladesh were randomized to receive a single dose of levamisole hydrochloride (150 mg) or no adjuvant to antimalarial treatment with intravenous artesunate. Results. Circulating late-stage parasites measured as the median area under the parasite clearance curves were 2150 (interquartile range [IQR], 0–28 025) parasites/µL × hour in patients treated with levamisole and 5489 (IQR, 192–25 848) parasites/µL × hour in controls (P = .25). The “sequestration ratios” at 6 and 12 hours for all parasite stages and changes in microvascular blood flow did not differ between treatment groups (all P > .40). The median time to normalization of plasma lactate (<2 mmol/L) was 24 (IQR, 12–30) hours with levamisole vs 28 (IQR, 12–36) hours without levamisole (P = .15). Conclusions. There was no benefit of a single-dose of levamisole hydrochloride as adjuvant to intravenous artesunate in the treatment of adults with severe falciparum malaria. Rapid parasite killing by intravenous artesunate might obscure the effects of levamisole. PMID:23943850
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A rapid malaria appraisal in the Venezuelan Amazon
2009-01-01
Background While the federal state of Amazonas bears the highest risk for malaria in Venezuela (2007: 68.4 cases/1000 inhabitants), little comprehensive information about the malaria situation is available from this area. The purpose of this rapid malaria appraisal (RMA) was to provide baseline data about malaria and malaria control in Amazonas. Methods The RMA methodology corresponds to a rapid health impact assessment (HIA) as described in the 1999 Gothenburg consensus. In conjunction with the actors of the malaria surveillance system, all useful data and information, which were accessible within a limited time-frame of five visits to Amazonas, were collected, analysed and interpreted. Results Mortality from malaria is low (< 1 in 105) and slide positivity rates have stayed at the same level for the last two decades (15% ± 6% (SD)). Active case detection accounts for ca. 40% of slides taken. The coverage of the censured population with malaria notification points (NPs) has been achieved in recent years. The main parasite is Plasmodium vivax (84% of cases). The proportion of Plasmodium falciparum is on the decline, possibly driven by the introduction of cost-free artemisinin-based combination therapy (ACT) (1988: 33.4%; 2007: 15.4%). Monitoring and documentation is complete, systematic and consistent, but poorly digitalized. Malaria transmission displayed a visible lag behind rainfall in the capital municipality of Atures, but not in the other municipalities. In comparison to reference microscopy, quality of field microscopy and rapid diagnostic tests (RDTs) is suboptimal (kappa < 0.75). Hot spots of malaria risk were seen in some indigenous ethnic groups. Conflicting strategies in respect of training of community health workers (CHW) and the introduction of new diagnostic tools (RDTs) were observed. Conclusion Malaria control is possible, even in tropical rain forest areas, if the health system is working adequately. Interventions have to be carefully designed
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INSECTICIDE-TREATED BED NETS IN RONDÔNIA, BRAZIL: EVALUATION OF THEIR IMPACT ON MALARIA CONTROL
Vieira, Gabriel de Deus; Basano, Sergio de Almeida; Katsuragawa, Tony Hiroshi; Camargo, Luís Marcelo Aranha
2014-01-01
Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region. PMID:25351543
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A Field Trial to Assess a Blood-Stage Malaria Vaccine
Thera, Mahamadou A.; Doumbo, Ogobara K.; Coulibaly, Drissa; Laurens, Matthew B.; Ouattara, Amed; Kone, Abdoulaye K.; Guindo, Ando B.; Traore, Karim; Traore, Idrissa; Kouriba, Bourema; Diallo, Dapa A.; Diarra, Issa; Daou, Modibo; Dolo, Amagana; Tolo, Youssouf; Sissoko, Mahamadou S.; Niangaly, Amadou; Sissoko, Mady; Takala-Harrison, Shannon; Lyke, Kirsten E.; Wu, Yukun; Blackwelder, William C.; Godeaux, Olivier; Vekemans, Johan; Dubois, Marie-Claude; Ballou, W. Ripley; Cohen, Joe; Thompson, Darby; Dube, Tina; Soisson, Lorraine; Diggs, Carter L.; House, Brent; Lanar, David E.; Dutta, Sheetij; Heppner, D. Gray; Plowe, Christopher V.
2011-01-01
BACKGROUND Blood-stage malaria vaccines are intended to prevent clinical disease. The malaria vaccine FMP2.1/AS02A, a recombinant protein based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, has previously been shown to have immunogenicity and acceptable safety in Malian adults and children. METHODS In a double-blind, randomized trial, we immunized 400 Malian children with either the malaria vaccine or a control (rabies) vaccine and followed them for 6 months. The primary end point was clinical malaria, defined as fever and at least 2500 parasites per cubic millimeter of blood. A secondary end point was clinical malaria caused by parasites with the AMA1 DNA sequence found in the vaccine strain. RESULTS The cumulative incidence of the primary end point was 48.4% in the malaria-vaccine group and 54.4% in the control group; efficacy against the primary end point was 17.4% (hazard ratio for the primary end point, 0.83; 95% confidence interval [CI], 0.63 to 1.09; P = 0.18). Efficacy against the first and subsequent episodes of clinical malaria, as defined on the basis of various parasite-density thresholds, was approximately 20%. Efficacy against clinical malaria caused by parasites with AMA1 corresponding to that of the vaccine strain was 64.3% (hazard ratio, 0.36; 95% CI, 0.08 to 0.86; P = 0.03). Local reactions and fever after vaccination were more frequent with the malaria vaccine. CONCLUSIONS On the basis of the primary end point, the malaria vaccine did not provide significant protection against clinical malaria, but on the basis of secondary results, it may have strain-specific efficacy. If this finding is confirmed, AMA1 might be useful in a multicomponent malaria vaccine. PMID:21916638
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Wang, Shr-Jie; Lengeler, Christian; Smith, Thomas A; Vounatsou, Penelope; Cissé, Guéladio; Tanner, Marcel
2006-01-01
Background Currently, there is a significant lack of knowledge concerning urban malaria patterns in general and in Abidjan in particular. The prevalence of malaria, its distribution in the city and the fractions of fevers attributable to malaria in the health facilities have not been previously investigated. Methods A health facility-based survey and health care system evaluation was carried out in a peripheral municipality of Abidjan (Yopougon) during the rainy season of 2002, applying a standardized Rapid Urban Malaria Appraisal (RUMA) methodology. Results According to national statistics, approximately 240,000 malaria cases (both clinical cases and laboratory confirmed cases) were reported by health facilities in the whole of Abidjan in 2001. They accounted for 40% of all consultations. In the health facilities of the Yopougon municipality, the malaria infection rates in fever cases for different age groups were 22.1% (under one year-olds), 42.8% (one to five years-olds), 42.0% (> five to 15 years-olds) and 26.8% (over 15 years-olds), while those in the control group were 13.0%. 26.7%, 21.8% and 14.6%, respectively. The fractions of malaria-attributable fever were 0.12, 0.22, 0.27 and 0.13 in the same age groups. Parasitaemia was homogenously detected in different areas of Yopougon. Among all children, 10.1% used a mosquito net (treated or not) the night before the survey and this was protective (OR = 0.52, 95% CI 0.29–0.97). Travel to rural areas within the last three months was frequent (31% of all respondents) and associated with a malaria infection (OR = 1.75, 95% CI 1.25–2.45). Conclusion Rapid urbanization has changed malaria epidemiology in Abidjan and endemicity was found to be moderate in Yopougon. Routine health statistics are not fully reliable to assess the burden of disease, and the low level of the fractions of malaria-attributable fevers indicated substantial over-treatment of malaria. PMID:16584575
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Fillinger, Ulrike; Kannady, Khadija; William, George; Vanek, Michael J; Dongus, Stefan; Nyika, Dickson; Geissbühler, Yvonne; Chaki, Prosper P; Govella, Nico J; Mathenge, Evan M; Singer, Burton H; Mshinda, Hassan; Lindsay, Steven W; Tanner, Marcel; Mtasiwa, Deo; de Castro, Marcia C; Killeen, Gerry F
2008-01-01
Background As the population of Africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed. Methods A recently initiated Urban Malaria Control Programme in Dar es Salaam delegates responsibility for routine mosquito control and surveillance to modestly-paid community members, known as Community-Owned Resource Persons (CORPs). New vector surveillance, larviciding and management systems were designed and evaluated in 15 city wards to allow timely collection, interpretation and reaction to entomologic monitoring data using practical procedures that rely on minimal technology. After one year of baseline data collection, operational larviciding with Bacillus thuringiensis var. israelensis commenced in March 2006 in three selected wards. Results The procedures and staff management systems described greatly improved standards of larval surveillance relative to that reported at the outset of this programme. In the first year of the programme, over 65,000 potential Anopheles habitats were surveyed by 90 CORPs on a weekly basis. Reaction times to vector surveillance at observations were one day, week and month at ward, municipal and city levels, respectively. One year of community-based larviciding reduced transmission by the primary malaria vector, Anopheles gambiae s.l., by 31% (95% C.I. = 21.6–37.6%; p = 0.04). Conclusion This novel management, monitoring and evaluation system for implementing routine larviciding of malaria vectors in African cities has shown considerable potential for sustained, rapidly responsive, data-driven and affordable application. Nevertheless, the true programmatic value of larviciding in urban Africa can only be established through longer-term programmes which are stably financed and allow the operational teams and management infrastructures to mature by learning from experience. PMID:18218148
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Models for short term malaria prediction in Sri Lanka
Briët, Olivier JT; Vounatsou, Penelope; Gunawardena, Dissanayake M; Galappaththy, Gawrie NL; Amerasinghe, Priyanie H
2008-01-01
Background Malaria in Sri Lanka is unstable and fluctuates in intensity both spatially and temporally. Although the case counts are dwindling at present, given the past history of resurgence of outbreaks despite effective control measures, the control programmes have to stay prepared. The availability of long time series of monitored/diagnosed malaria cases allows for the study of forecasting models, with an aim to developing a forecasting system which could assist in the efficient allocation of resources for malaria control. Methods Exponentially weighted moving average models, autoregressive integrated moving average (ARIMA) models with seasonal components, and seasonal multiplicative autoregressive integrated moving average (SARIMA) models were compared on monthly time series of district malaria cases for their ability to predict the number of malaria cases one to four months ahead. The addition of covariates such as the number of malaria cases in neighbouring districts or rainfall were assessed for their ability to improve prediction of selected (seasonal) ARIMA models. Results The best model for forecasting and the forecasting error varied strongly among the districts. The addition of rainfall as a covariate improved prediction of selected (seasonal) ARIMA models modestly in some districts but worsened prediction in other districts. Improvement by adding rainfall was more frequent at larger forecasting horizons. Conclusion Heterogeneity of patterns of malaria in Sri Lanka requires regionally specific prediction models. Prediction error was large at a minimum of 22% (for one of the districts) for one month ahead predictions. The modest improvement made in short term prediction by adding rainfall as a covariate to these prediction models may not be sufficient to merit investing in a forecasting system for which rainfall data are routinely processed. PMID:18460204
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Brady, Oliver J.; Godfray, H. Charles J.; Tatem, Andrew J.; Gething, Peter W.; Cohen, Justin M.; McKenzie, F. Ellis; Perkins, T. Alex; Reiner, Robert C.; Tusting, Lucy S.; Sinka, Marianne E.; Moyes, Catherine L.; Eckhoff, Philip A.; Scott, Thomas W.; Lindsay, Steven W.; Hay, Simon I.; Smith, David L.
2016-01-01
Background Major gains have been made in reducing malaria transmission in many parts of the world, principally by scaling-up coverage with long-lasting insecticidal nets and indoor residual spraying. Historically, choice of vector control intervention has been largely guided by a parameter sensitivity analysis of George Macdonald's theory of vectorial capacity that suggested prioritizing methods that kill adult mosquitoes. While this advice has been highly successful for transmission suppression, there is a need to revisit these arguments as policymakers in certain areas consider which combinations of interventions are required to eliminate malaria. Methods and Results Using analytical solutions to updated equations for vectorial capacity we build on previous work to show that, while adult killing methods can be highly effective under many circumstances, other vector control methods are frequently required to fill effective coverage gaps. These can arise due to pre-existing or developing mosquito physiological and behavioral refractoriness but also due to additive changes in the relative importance of different vector species for transmission. Furthermore, the optimal combination of interventions will depend on the operational constraints and costs associated with reaching high coverage levels with each intervention. Conclusions Reaching specific policy goals, such as elimination, in defined contexts requires increasingly non-generic advice from modelling. Our results emphasize the importance of measuring baseline epidemiology, intervention coverage, vector ecology and program operational constraints in predicting expected outcomes with different combinations of interventions. PMID:26822603
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2014-01-01
Background The impact of the age of first Plasmodium falciparum infection on the rate of acquisition of immunity to malaria and on the immune correlates of protection has proven difficult to elucidate. A randomized, double-blind, placebo-controlled trial using monthly chemoprophylaxis with sulphadoxine-pyrimethamine plus artesunate was conducted to modify the age of first P. falciparum erythrocytic exposure in infancy and assess antibodies and malaria risk over two years. Methods Participants (n = 349) were enrolled at birth to one of three groups: late exposure, early exposure and control group, and were followed up for malaria morbidity and immunological analyses at birth, 2.5, 5.5, 10.5, 15 and 24 months of age. Total IgG, IgG subclasses and IgM responses to MSP-119, AMA-1, and EBA-175 were measured by ELISA, and IgG against variant antigens on the surface of infected erythrocytes by flow cytometry. Factors affecting antibody responses in relation to chemoprophylaxis and malaria incidence were evaluated. Results Generally, antibody responses did not vary significantly between exposure groups except for levels of IgM to EBA-175, and seropositivity of IgG1 and IgG3 to MSP-119. Previous and current malaria infections were strongly associated with increased IgG against MSP-119, EBA-175 and AMA-1 (p < 0.0001). After adjusting for exposure, only higher levels of anti-EBA-175 IgG were significantly associated with reduced clinical malaria incidence (IRR 0.67, p = 0.0178). Conclusions Overall, the age of first P. falciparum infection did not influence the magnitude and breadth of IgG responses, but previous exposure was critical for antibody acquisition. IgG responses to EBA-175 were the strongest correlate of protection against clinical malaria. Trial registration ClinicalTrials.gov: NCT00231452. PMID:24674654
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Mohammed-Awel, Jemal; Numfor, Eric
2017-03-01
We propose and study a mathematical model for malaria-HIV co-infection transmission and control, in which malaria treatment and insecticide-treated nets are incorporated. The existence of a backward bifurcation is established analytically, and the occurrence of such backward bifurcation is influenced by disease-induced mortality, insecticide-treated bed-net coverage and malaria treatment parameters. To further assess the impact of malaria treatment and insecticide-treated bed-net coverage, we formulate an optimal control problem with malaria treatment and insecticide-treated nets as control functions. Using reasonable parameter values, numerical simulations of the optimal control suggest the possibility of eliminating malaria and reducing HIV prevalence significantly, within a short time horizon.
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2016-01-01
Background In moving toward malaria elimination, one strategy is to implement an active surveillance system for effective case management. Thailand has developed and implemented the electronic Malaria Information System (eMIS) capturing individualized electronic records of suspected or confirmed malaria cases. Objective The main purpose of this study was to determine how well the eMIS improves the quality of Thailand’s malaria surveillance system. In particular, the focus of the study was to evaluate the effectiveness of the eMIS in terms of the system users’ perception and the system outcomes (ie, quality of data) regarding the management of malaria patients. Methods A mixed-methods technique was used with the framework based on system effectiveness attributes: data quality, timeliness, simplicity, acceptability, flexibility, stability, and usefulness. Three methods were utilized: data records review, survey of system users, and in-depth interviews with key stakeholders. From the two highest endemic provinces, paper forms matching electronic records of 4455 noninfected and 784 malaria-infected cases were reviewed. Web-based anonymous questionnaires were distributed to all 129 eMIS data entry staff throughout Thailand, and semistructured interviews were conducted with 12 management-level officers. Results The eMIS is well accepted by system users at both management and operational levels. The data quality has enabled malaria personnel to perform more effective prevention and control activities. There is evidence of practices resulting in inconsistencies and logical errors in data reporting. Critical data elements were mostly completed, except for a few related to certain dates and area classifications. Timeliness in reporting a case to the system was acceptable with a delay of 3-4 days. The evaluation of quantitative and qualitative data confirmed that the eMIS has high levels of simplicity, acceptability, stability, and flexibility. Conclusions Overall, the
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Renewed mobilization against malaria.
1991-01-01
1 million people die in the world from malaria annually, 800,000 of whom are 5 year old children in Sub-Sahara Africa. Further it affects 270 million people. In fact, 110 million develop malaria, 90 million of whom are from Sub-Saharan Africa. Thus WHO has introduced a new world initiative for malaria control to reverse the worsening trend that began in the mid 1970s. In October 1991, 150 officials from 50 African, Asian, and Latin American countries and participants from UN cooperation and development agencies and bilateral agencies attended an interregional conference at the WHO Regional office for Africa in Brazzaville, Congo. It strove to evaluate malaria situations specific to Africa, to update the malaria control plan in Africa, and to contribute to the development of an implementable world strategy. This world strategy needs to consider the local situation and encourage participation of the government and people of affected countries. Further individuals, communities, and various sectors of the national economy including those involved in health, education, development, and agriculture need to participate in malaria control. In addition, for this strategy to work, most countries must strengthen the management and financing of health services to meet their needs. For example, local populations must share local operating costs such as those for essential drugs and mosquito control operations. Community participation must also include personal protection such as impregnated bed nets and environmental measures. Besides malaria control must be integrated into the existing health system at country, provincial, and peripheral levels. In sum, improved case management, control of malaria transmission, and prevention and control of epidemics form the basis for the new strategy.
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Paratransgenesis to control malaria vectors: a semi-field pilot study.
Mancini, Maria Vittoria; Spaccapelo, Roberta; Damiani, Claudia; Accoti, Anastasia; Tallarita, Mario; Petraglia, Elisabetta; Rossi, Paolo; Cappelli, Alessia; Capone, Aida; Peruzzi, Giulia; Valzano, Matteo; Picciolini, Matteo; Diabaté, Abdoulaye; Facchinelli, Luca; Ricci, Irene; Favia, Guido
2016-03-10
Malaria still remains a serious health burden in developing countries, causing more than 1 million deaths annually. Given the lack of an effective vaccine against its major etiological agent, Plasmodium falciparum, and the growing resistance of this parasite to the currently available drugs repertoire and of Anopheles mosquitoes to insecticides, the development of innovative control measures is an imperative to reduce malaria transmission. Paratransgenesis, the modification of symbiotic organisms to deliver anti-pathogen effector molecules, represents a novel strategy against Plasmodium development in mosquito vectors, showing the potential to reduce parasite development. However, the field application of laboratory-based evidence of paratransgenesis imposes the use of more realistic confined semi-field environments. Large cages were used to evaluate the ability of bacteria of the genus Asaia expressing green fluorescent protein (Asaia (gfp)), to diffuse in Anopheles stephensi and Anopheles gambiae target mosquito populations. Asaia (gfp) was introduced in large cages through the release of paratransgenic males or by sugar feeding stations. Recombinant bacteria transmission was directly detected by fluorescent microscopy, and further assessed by molecular analysis. Here we show the first known trial in semi-field condition on paratransgenic anophelines. Modified bacteria were able to spread at high rate in different populations of An. stephensi and An. gambiae, dominant malaria vectors, exploring horizontal ways and successfully colonising mosquito midguts. Moreover, in An. gambiae, vertical and trans-stadial diffusion mechanisms were demonstrated. Our results demonstrate the considerable ability of modified Asaia to colonise different populations of malaria vectors, including pecies where its association is not primary, in large environments. The data support the potential to employ transgenic Asaia as a tool for malaria control, disclosing promising perspective
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Hassanpour, Gholmreza; Mohebali, Mehdi; Zeraati, Hojjat; Raeisi, Ahmad; Keshavarz, Hossein
2017-01-01
Background: The objective of this study was to find an appropriate approach to asymptomatic malaria in elimination setting through a systematic review. Methods: A broad search was conducted to find articles with the words ‘malaria’ in their titles and ‘asymptomatic’ or ‘submicroscopic’ in their texts, irrespective of the type of study conducted. The Cochrane, Medline/Pub Med, and Scopus databases, as well as Google Scholar were systematically searched for English articles and reports and Iran’s databases-Iran Medex, SID and Magiran were searched for Persian reports and articles, with no time limitation. The study was qualitatively summarized if it contained precise information on the role of asymptomatic malaria in the elimination phase. Results: Six articles were selected from the initial 2645 articles. The results all re-emphasize the significance of asymptomatic malaria in the elimination phase, and emphasize the significance of diagnostic tests of higher sensitivity to locate these patients and perform interventions to reduce the asymptomatic parasitic reservoirs particularly in regions of low transmission. However, we may infer from the results that the current evidence cannot yet specify an accurate strategy on the role of asymptomatic malaria in the elimination phase. Conclusion: To eliminate malaria, alongside vector control, and treatment of symptomatic and asymptomatic patients, active and inactive methods of case detection need to be employed. The precise monitoring of asymptomatic individuals and submicroscopic cases of malaria through molecular assays and valid serological methods, especially in regions where seasonal and low transmission exists can be very helpful at this phase. PMID:29062842
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Quiñones, Martha L.; Norris, Douglas E.; Conn, Jan E.; Moreno, Marta; Burkot, Thomas R.; Bugoro, Hugo; Keven, John B.; Cooper, Robert; Yan, Guiyun; Rosas, Angel; Palomino, Miriam; Donnelly, Martin J.; Mawejje, Henry D.; Eapen, Alex; Montgomery, Jacqui; Coulibaly, Mamadou B.; Beier, John C.; Kumar, Ashwani
2015-01-01
Scale-up of the main vector control interventions, residual insecticides sprayed on walls or structures and/or impregnated in bed nets, together with prompt diagnosis and effective treatment, have led to a global reduction in malaria transmission. However, resistance in vectors to almost all classes of insecticides, particularly to the synthetic pyrethroids, is posing a challenge to the recent trend of declining malaria. Ten International Centers of Excellence for Malaria Research (ICEMR) located in the most malaria-endemic regions of the world are currently addressing insecticide resistance in the main vector populations, which not only threaten hope for elimination in malaria-endemic countries but also may lead to reversal where notable reductions in malaria have been documented. This communication illustrates the current status of insecticide resistance with a focus on the countries where activities are ongoing for 9 out of the 10 ICEMRs. Most of the primary malaria vectors in the ICEMR countries exhibit insecticide resistance, albeit of varying magnitude, and spanning all mechanisms of resistance. New alternatives to the insecticides currently available are still to be fully developed for deployment. Integrated vector management principles need to be better understood and encouraged, and viable insecticide resistance management strategies need to be developed and implemented. PMID:26259947
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Tseroni, Maria; Baka, Agoritsa; Kapizioni, Christina; Snounou, Georges; Tsiodras, Sotirios; Charvalakou, Maria; Georgitsou, Maria; Panoutsakou, Maria; Psinaki, Ioanna; Tsoromokou, Maria; Karakitsos, George; Pervanidou, Danai; Vakali, Annita; Mouchtouri, Varvara; Georgakopoulou, Theano; Mamuris, Zissis; Papadopoulos, Nikos; Koliopoulos, George; Badieritakis, Evangelos; Diamantopoulos, Vasilis; Tsakris, Athanasios; Kremastinou, Jenny; Hadjichristodoulou, Christos
2015-11-01
Greece was declared malaria-free in 1974 after a long antimalarial fight. In 2011-2012, an outbreak of P. vivax malaria was reported in Evrotas, an agricultural area in Southern Greece, where a large number of immigrants from endemic countries live and work. A total of 46 locally acquired and 38 imported malaria cases were detected. Despite a significant decrease of the number of malaria cases in 2012, a mass drug administration (MDA) program was considered as an additional measure to prevent reestablishment of the disease in the area. During 2013 and 2014, a combination of 3-day chloroquine and 14-day primaquine treatment was administered under direct observation to immigrants living in the epicenter of the 2011 outbreak in Evrotas. Adverse events were managed and recorded on a daily basis. The control measures implemented since 2011 continued during the period of 2013-2014 as a part of a national integrated malaria control program that included active case detection (ACD), vector control measures and community education. The MDA program was started prior to the transmission periods (from May to December). One thousand ninety four (1094) immigrants successfully completed the treatment, corresponding to 87.3% coverage of the target population. A total of 688 adverse events were recorded in 397 (36.2%, 95% C.I.: 33.4-39.1) persons, the vast majority minor, predominantly dizziness and headache for chloroquine (284 events) and abdominal pain (85 events) for primaquine. A single case of primaquine-induced hemolysis was recorded in a person whose initial G6PD test proved incorrect. No malaria cases were recorded in Evrotas, Laconia, in 2013 and 2014, though three locally acquired malaria cases were recorded in other regions of Greece in 2013. Preventive antimalarial MDA to a high-risk population in a low transmission setting appears to have synergized with the usual antimalarial activities to achieve malaria elimination. This study suggests that judicious use of MDA can
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Tseroni, Maria; Baka, Agoritsa; Kapizioni, Christina; Snounou, Georges; Tsiodras, Sotirios; Charvalakou, Maria; Georgitsou, Maria; Panoutsakou, Maria; Psinaki, Ioanna; Tsoromokou, Maria; Karakitsos, George; Pervanidou, Danai; Vakali, Annita; Mouchtouri, Varvara; Georgakopoulou, Theano; Mamuris, Zissis; Papadopoulos, Nikos; Koliopoulos, George; Badieritakis, Evangelos; Diamantopoulos, Vasilis; Tsakris, Athanasios; Kremastinou, Jenny; Hadjichristodoulou, Christos
2015-01-01
Greece was declared malaria-free in 1974 after a long antimalarial fight. In 2011–2012, an outbreak of P. vivax malaria was reported in Evrotas, an agricultural area in Southern Greece, where a large number of immigrants from endemic countries live and work. A total of 46 locally acquired and 38 imported malaria cases were detected. Despite a significant decrease of the number of malaria cases in 2012, a mass drug administration (MDA) program was considered as an additional measure to prevent reestablishment of the disease in the area. During 2013 and 2014, a combination of 3-day chloroquine and 14-day primaquine treatment was administered under direct observation to immigrants living in the epicenter of the 2011 outbreak in Evrotas. Adverse events were managed and recorded on a daily basis. The control measures implemented since 2011 continued during the period of 2013–2014 as a part of a national integrated malaria control program that included active case detection (ACD), vector control measures and community education. The MDA program was started prior to the transmission periods (from May to December). One thousand ninety four (1094) immigrants successfully completed the treatment, corresponding to 87.3% coverage of the target population. A total of 688 adverse events were recorded in 397 (36.2%, 95% C.I.: 33.4–39.1) persons, the vast majority minor, predominantly dizziness and headache for chloroquine (284 events) and abdominal pain (85 events) for primaquine. A single case of primaquine-induced hemolysis was recorded in a person whose initial G6PD test proved incorrect. No malaria cases were recorded in Evrotas, Laconia, in 2013 and 2014, though three locally acquired malaria cases were recorded in other regions of Greece in 2013. Preventive antimalarial MDA to a high-risk population in a low transmission setting appears to have synergized with the usual antimalarial activities to achieve malaria elimination. This study suggests that judicious use of
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THE IMPORTANCE OF MOSQUITO BEHAVIOURAL ADAPTATIONS TO MALARIA CONTROL IN AFRICA
Gatton, Michelle L; Chitnis, Nakul; Churcher, Thomas; Donnelly, Martin J; Ghani, Azra C; Godfray, H Charles J; Gould, Fred; Hastings, Ian; Marshall, John; Ranson, Hilary; Rowland, Mark; Shaman, Jeff; Lindsay, Steve W; Meagher, T
2013-01-01
Over the past decade the use of long-lasting insecticidal nets (LLINs), in combination with improved drug therapies, indoor residual spraying (IRS), and better health infrastructure, has helped reduce malaria in many African countries for the first time in a generation. However, insecticide resistance in the vector is an evolving threat to these gains. We review emerging and historical data on behavioral resistance in response to LLINs and IRS. Overall the current literature suggests behavioral and species changes may be emerging, but the data are sparse and, at times unconvincing. However, preliminary modeling has demonstrated that behavioral resistance could have significant impacts on the effectiveness of malaria control. We propose seven recommendations to improve understanding of resistance in malaria vectors. Determining the public health impact of physiological and behavioral insecticide resistance is an urgent priority if we are to maintain the significant gains made in reducing malaria morbidity and mortality. PMID:23550770
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Nonaka, Daisuke; Jimba, Masamine; Mizoue, Tetsuya; Kobayashi, Jun; Yasuoka, Junko; Ayi, Irene; Jayatilleke, Achini C.; Shrestha, Sabina; Kikuchi, Kimiyo; Haque, Syed E.; Yi, Siyan
2012-01-01
Background In tropical settings, malaria education at school is potentially useful, but textbook content related to malaria education has so far received little attention. This study aimed to examine whether school textbooks contain sufficient knowledge and skills to help children in primary and lower secondary schools and their family members to cope with malaria. Methodology/Principal Findings This was a descriptive, cross-country study. We collected textbooks that were used by children in grades one to nine from nine countries endemic for malaria: Laos, Cambodia, Nepal, Bangladesh, Sri Lanka, Zambia, Niger, Benin, and Ghana. Two reviewers per country identified descriptions about malaria by seeking the term “malaria” or a local word that corresponds to malaria in languages other than English. The authors categorized the identified descriptions according to the content of the descriptions. Additionally, the authors examined whether the identified contents addressed life skill messages. Of a total of 474 textbooks collected, 35 contained descriptions about malaria. The most commonly included content was transmission mode/vector (77.1%), followed by preventive measures (60.0%), epidemiology (57.1%), cause/agent (54.3%), signs/symptoms (37.1%) and treatment (22.9%). Treatment-related content was not included in any textbooks from four countries and textbooks failed to recommend the use of insecticide-treated bed nets in five countries. Very few textbooks included content that facilitated prompt treatment, protection of risk groups, and use of recommended therapy. Conclusion/Significance Textbooks rarely included knowledge and skills that are crucial to protect schoolchildren and their families from malaria. This study identified the need for improvement to textbook contents regarding malaria. PMID:22574203
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Shirayama, Yoshihisa; Phompida, Samlane; Shibuya, Kenji
2009-01-01
Background Insecticide-treated nets (ITNs) are a key intervention to control malaria. The intervention coverage varies as a consequence of geographical accessibility to remote villages and limitations of financial and human resources for the intervention. People's adherence to the intervention, i.e., proper use of ITNs, also affects malaria health outcome. The study objective is to explore the impact of the intervention coverage and people's adherence to the intervention on malaria health outcome among targeted villages in various geographic locations. Methods Geographic information system (GIS) maps were developed using the data collected in an active case detection survey in Khammouane province, Laos. The survey was conducted using rapid diagnostic tests (RDTs) and a structured questionnaire at 23 sites in the province from June to July, the rainy season, in 2005. A total of 1,711 villagers from 403 households participated in the survey. Results As indicated on the GIS maps, villages with malaria cases, lower intervention coverage, and lower adherence were identified. Although no malaria case was detected in most villages with the best access to the district center, several cases were detected in the distal villages, where the intervention coverage and adherence to the intervention remained relatively lower. Conclusion Based on the data and maps, it was demonstrated that malaria remained unevenly distributed within districts. Balancing the intervention coverage in the distal villages with the overall coverage and continued promotion of the proper use of ITNs are necessary for a further reduction of malaria cases in the province. PMID:19772628
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Zhou, Shui-sen; Rietveld, Aafje E C; Velarde-Rodriguez, Mar; Ramsay, Andrew R; Zhang, Shao-sen; Zhou, Xiao-nong; Cibulskis, Richard E
2014-12-04
A literature review for operational research on malaria control and elimination was conducted using the term 'malaria' and the definition of operational research (OR). A total of 15 886 articles related to malaria were searched between January 2008 and June 2013. Of these, 582 (3.7%) met the definition of operational research. These OR projects had been carried out in 83 different countries. Most OR studies (77%) were implemented in Africa south of the Sahara. Only 5 (1%) of the OR studies were implemented in countries in the pre-elimination or elimination phase. The vast majority of OR projects (92%) were led by international or local research institutions, while projects led by National Malaria Control Programmes (NMCP) accounted for 7.8%. With regards to the topic under investigation, the largest percentage of papers was related to vector control (25%), followed by epidemiology/transmission (16.5%) and treatment (16.3%). Only 19 (3.8%) of the OR projects were related to malaria surveillance. Strengthening the capacity of NMCPs to conduct operational research and publish its findings, and improving linkages between NMCPs and research institutes may aid progress towards malaria elimination and eventual eradication world-wide.
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Vaccine approaches to malaria control and elimination: Insights from mathematical models.
White, Michael T; Verity, Robert; Churcher, Thomas S; Ghani, Azra C
2015-12-22
A licensed malaria vaccine would provide a valuable new tool for malaria control and elimination efforts. Several candidate vaccines targeting different stages of the malaria parasite's lifecycle are currently under development, with one candidate, RTS,S/AS01 for the prevention of Plasmodium falciparum infection, having recently completed Phase III trials. Predicting the public health impact of a candidate malaria vaccine requires using clinical trial data to estimate the vaccine's efficacy profile--the initial efficacy following vaccination and the pattern of waning of efficacy over time. With an estimated vaccine efficacy profile, the effects of vaccination on malaria transmission can be simulated with the aid of mathematical models. Here, we provide an overview of methods for estimating the vaccine efficacy profiles of pre-erythrocytic vaccines and transmission-blocking vaccines from clinical trial data. In the case of RTS,S/AS01, model estimates from Phase II clinical trial data indicate a bi-phasic exponential profile of efficacy against infection, with efficacy waning rapidly in the first 6 months after vaccination followed by a slower rate of waning over the next 4 years. Transmission-blocking vaccines have yet to be tested in large-scale Phase II or Phase III clinical trials so we review ongoing work investigating how a clinical trial might be designed to ensure that vaccine efficacy can be estimated with sufficient statistical power. Finally, we demonstrate how parameters estimated from clinical trials can be used to predict the impact of vaccination campaigns on malaria using a mathematical model of malaria transmission. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Effect of Investment in Malaria Control on Child Mortality in Sub-Saharan Africa in 2002–2008
Akachi, Yoko; Atun, Rifat
2011-01-01
Background Around 8.8 million children under-five die each year, mostly due to infectious diseases, including malaria that accounts for 16% of deaths in Africa, but the impact of international financing of malaria control on under-five mortality in sub-Saharan Africa has not been examined. Methods and Findings We combined multiple data sources and used panel data regression analysis to study the relationship among investment, service delivery/intervention coverage, and impact on child health by observing changes in 34 sub-Saharan African countries over 2002–2008. We used Lives Saved Tool to estimate the number of lives saved from coverage increase of insecticide-treated nets (ITNs)/indoor residual spraying (IRS). As an indicator of outcome, we also used under-five mortality rate. Global Fund investments comprised more than 70% of the Official Development Assistance (ODA) for malaria control in 34 countries. Each $1 million ODA for malaria enabled distribution of 50,478 ITNs [95%CI: 37,774–63,182] in the disbursement year. 1,000 additional ITNs distributed saved 0.625 lives [95%CI: 0.369–0.881]. Cumulatively Global Fund investments that increased ITN/IRS coverage in 2002–2008 prevented an estimated 240,000 deaths. Countries with higher malaria burden received less ODA disbursement per person-at-risk compared to lower-burden countries ($3.90 vs. $7.05). Increased ITN/IRS coverage in high-burden countries led to 3,575 lives saved per 1 million children, as compared with 914 lives in lower-burden countries. Impact of ITN/IRS coverage on under-five mortality was significant among major child health interventions such as immunisation showing that 10% increase in households with ITN/IRS would reduce 1.5 [95%CI: 0.3–2.8] child deaths per 1000 live births. Conclusions Along with other key child survival interventions, increased ITNs/IRS coverage has significantly contributed to child mortality reduction since 2002. ITN/IRS scale-up can be more efficiently
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Human ecology and behaviour in malaria control in tropical Africa
MacCormack, C. P.
1984-01-01
Since about 250 BC, human modification of African environments has created increasingly favourable breeding conditions for Anopheles gambiae. Subsequent adaptations to the increased malaria risk are briefly described and reference is made to Macdonald's mathematical model for the disease. Since values for the variables in that model are high in tropical Africa, there is little possibility that simple, inexpensive, self-help primary health care initiatives can control malaria in the region. However, in combination with more substantial public health initiatives, simple primary health care activities might be done by communities to (1) prevent mosquitos from feeding on people, (2) prevent or reduce mosquito breeding, (3) destroy adult mosquitos, and (4) eliminate malaria parasites from human hosts. Lay methods of protection and self-care are examined and some topics for further research are indicated. Culturally appropriate health education methods are also suggested. PMID:6335685
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Malaria successes and challenges in Asia.
Bhatia, Rajesh; Rastogi, Rakesh Mani; Ortega, Leonard
2013-12-01
Asia ranks second to Africa in terms of malaria burden. In 19 countries of Asia, malaria is endemic and 2.31 billion people or 62% of the total population in these countries are at risk of malaria. In 2010, WHO estimated around 34.8 million cases and 45,600 deaths due to malaria in Asia. In 2011, 2.7 million cases and > 2000 deaths were reported. India, Indonesia, Myanmar and Pakistan are responsible for >85% of the reported cases (confirmed) and deaths in Asia. In last 10 yr, due to availability of donor's fund specially from Global fund, significant progress has been made by the countries in Asia in scaling-up malaria control interventions which were instrumental in reducing malaria morbidity and mortality significantly. There is a large heterogeneity in malaria epidemiology in Asia. As a result, the success in malaria control/elimination is also diverse. As compared to the data of the year 2000, out of 19 malaria endemic countries, 12 countries were able to reduce malaria incidence (microscopically confirmed cases only) by 75%. Two countries, namely Bangladesh and Malaysia are projected to reach 75% reduction by 2015 while India is projected to reach 50-75% only by 2015. The trend could not be assessed in four countries, namely Indonesia, Myanmar, Pakistan and Timor-Leste due to insufficient consistent data. Numerous key challenges need to be addressed to sustain the gains and eliminate malaria in most parts of Asia. Some of these are to control the spread of resistance in Plasmodium falciparum to artemisinin, control of outdoor transmission, control of vivax malaria and ensuring universal coverage of key interventions. Asia has the potential to influence the malaria epidemiology all over the world as well as to support the global efforts in controlling and eliminating malaria through production of quality-assured ACTs, RDTs and long-lasting insecticidal nets.
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Laurens, Matthew B; Duncan, Christopher J; Epstein, Judith E; Hill, Adrian V; Komisar, Jack L; Lyke, Kirsten E; Ockenhouse, Christian F; Richie, Thomas L; Roestenberg, Meta; Sauerwein, Robert W; Spring, Michele D; Talley, Angela K; Moorthy, Vasee S
2012-08-03
Early clinical investigations of candidate malaria vaccines and antimalarial medications increasingly employ an established model of controlled human malaria infection (CHMI). Study results are used to guide further clinical development of vaccines and antimalarial medications as CHMI results to date are generally predictive of efficacy in malaria-endemic areas. The urgency to rapidly develop an efficacious malaria vaccine has increased demand for efficacy studies that include CHMI and the need for comparability of study results among the different centres conducting CHMI. An initial meeting with the goal to optimize and standardise CHMI procedures was held in 2009 with follow-up meetings in March and June 2010 to harmonise methods used at different centres. The end result is a standardised document for the design and conduct of CHMI and a second document for the microscopy methods used to determine the patency endpoint. These documents will facilitate high accuracy and comparability of CHMI studies and will be revised commensurate with advances in the field. Copyright © 2012. Published by Elsevier Ltd.. All rights reserved.
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2013-01-01
Background Although, Plasmodium vivax is a rare parasite in most parts of Africa, it has significant public health importance in Ethiopia. In some parts of the country, it is responsible for majority of malaria associated morbidity. Recently severe life threatening malaria syndromes, frequently associated to P. falciparum, has been reported from P. vivax mono-infections. This prompted designing of the current study to assess prevalence of severe malaria complications related to P. vivax malaria in Ethiopia. Methods The study was conducted in two study sites, namely Kersa and Halaba Kulito districts, located in southwest and southern parts of Ethiopia, respectively. Children, aged ≤ 10 years, who visited the two health centers during the study period, were recruited to the study. Clinical and demographic characteristics such as age, sex, temperature, diarrhea, persistent vomiting, confusion, respiratory distress, hepatomegaly, splenomegaly, hemoglobinuria, and epitaxis were assessed for a total of 139 children diagnosed to have P. vivax mono-infection. Parasitological data were collected following standard procedures. Hemoglobin and glucose level were measured using portable hemocue instrument. Results Median age of children was 4.25 ± 2.95 years. Geometric mean parasite count and mean hemoglobin level were 4254.89 parasite/μl and 11.55 g/dl, respectively. Higher prevalence rate of malaria and severe malaria complications were observed among children enrolled in Halaba district (P < 0.001). However, severe parasitemia was higher (72.4%) among children who visited Serbo health center (Kersa district). Male children had significantly higher risk of malaria infection (OR = 1.9, 95% CI, 1.08 to 3.34), while female had higher risk to anemia (OR = 1.91, 95% CI, 1.08 - 3.34). The observed number of anemic children was 43%, of which most of them were found in age range from 0–3 years. Furthermore, P. vivax malaria was a risk factor for incidence of anemia (P < 0
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Hershey, Christine L; Florey, Lia S; Ali, Doreen; Bennett, Adam; Luhanga, Misheck; Mathanga, Don P; Salgado, S René; Nielsen, Carrie F; Troell, Peter; Jenda, Gomezgani; Yé, Yazoume; Bhattarai, Achuyt
2017-09-01
Malaria control intervention coverage increased nationwide in Malawi during 2000-2010. Trends in intervention coverage were assessed against trends in malaria parasite prevalence, severe anemia (hemoglobin < 8 g/dL), and all-cause mortality in children under 5 years of age (ACCM) using nationally representative household surveys. Associations between insecticide-treated net (ITN) ownership, malaria morbidity, and ACCM were also assessed. Household ITN ownership increased from 27.4% (95% confidence interval [CI] = 25.9-29.0) in 2004 to 56.8% (95% CI = 55.6-58.1) in 2010. Similarly intermittent preventive treatment during pregnancy coverage increased from 28.2% (95% CI = 26.7-29.8) in 2000 to 55.0% (95% CI = 53.4-56.6) in 2010. Malaria parasite prevalence decreased significantly from 60.5% (95% CI = 53.0-68.0) in 2001 to 20.4% (95% CI = 15.7-25.1) in 2009 in children aged 6-35 months. Severe anemia prevalence decreased from 20.4% (95% CI: 17.3-24.0) in 2004 to 13.1% (95% CI = 11.0-15.4) in 2010 in children aged 6-23 months. ACCM decreased 41%, from 188.6 deaths per 1,000 live births (95% CI = 179.1-198.0) during 1996-2000, to 112.1 deaths per 1,000 live births (95% CI = 105.8-118.5) during 2006-2010. When controlling for other covariates in random effects logistic regression models, household ITN ownership was protective against malaria parasitemia in children (odds ratio [OR] = 0.81, 95% CI = 0.72-0.92) and severe anemia (OR = 0.82, 95% CI = 0.72-0.94). After considering the magnitude of changes in malaria intervention coverage and nonmalaria factors, and given the contribution of malaria to all-cause mortality in malaria-endemic countries, the substantial increase in malaria control interventions likely improved child survival in Malawi during 2000-2010.
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Etang, Josiane; Nwane, Philippe; Piameu, Michael; Manga, Blaise; Souop, Daniel; Awono-Ambene, Parfait
2013-01-01
Background From 2006 to 2011, biological activity of insecticides for Indoor Residual Spraying (IRS), conventional treatment of nets (CTNs) or long lasting insecticidal nets (LLINs) was evaluated before their approval in Cameroon. The objective of the study was to select the best tools for universal malaria vector control coverage. Methodology Bioassays were performed using WHO cones and the Kisumu susceptible strain of Anopheles gambiae s.s.. Among tested products, residual activity and wash resistance of Alpha-cypermethrin LLINs (Interceptor) and CTNs (Fendona) were assessed during 5 months in the Ntougou neighborhood. Principal Findings All the 14 tested products were found effective (95–100% knockdown and mortality rates), although a significant decrease of efficacy was seen with lambda-cyhalothrinWP IRS, alpha-cypermethrin CTNs and LLINs (p< 0.05). However, the efficacy of Interceptor nets did not decrease during the 5 months evaluation, even after 25 washes (0.07
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Malaria rapid diagnostic tests.
Wilson, Michael L
2012-06-01
Global efforts to control malaria are more complex than those for other infectious diseases, in part because of vector transmission, the complex clinical presentation of Plasmodium infections, >1 Plasmodium species causing infection, geographic distribution of vectors and infection, and drug resistance. The World Health Organization approach to global malaria control focuses on 2 components: vector control and diagnosis and treatment of clinical malaria. Although microscopy performed on peripheral blood smears remains the most widely used diagnostic test and the standard against which other tests are measured, rapid expansion of diagnostic testing worldwide will require use of other diagnostic approaches. This review will focus on the malaria rapid diagnostic test (MRDT) for detecting malaria parasitemia, both in terms of performance characteristics of MRDTs and how they are used under field conditions. The emphasis will be on the performance and use of MRDTs in regions of endemicity, particularly sub-Saharan Africa, where most malaria-related deaths occur.
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Reduced risk for placental malaria in iron deficient women
2011-01-01
Background Nutritional iron deficiency may limit iron availability to the malaria parasite reducing infection risk, and/or impair host immunity thereby increasing this risk. In pregnant women, there is evidence of an adverse effect with iron supplementation, but the few reported studies are strongly confounded. Methods A case control study in pregnant Malawian women was undertaken in Chikhwawa southern Malawi in order to describe iron status in relation to placental malaria controlling for several confounding factors. Pregnancy characteristics were obtained and a blood sample at delivery. A full blood count was performed and serum ferritin and transferrin receptor quantified by enzyme-linked immunoassay. DNA analysis was used to identify genetic polymorphisms for ABO phenotype, hemoglobin HbS, and glucose -6 phosphate dehydrogenase deficiency. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection. Results 112 cases with placental malaria were identified and 110 women with no evidence of placental infection. Iron deficiency was less frequent in women with placental Plasmodium falciparum infection. In those with acute, chronic or past placental infections the odds ratio for iron deficiency was 0.4, 95% CI 0.2-0.8, p = 0.01; for acute and chronic infections 0.4, 0.2-0.8, p = 0.006; for acute infection 0.3, 0.1-0.7, p = 0.001. The association was greater in multigravidae. Conclusion Women with either acute, or acute and chronic placental malaria were less likely to have iron deficiency than women without placental malaria infection There is a priority to establish if reversing iron deficiency through iron supplementation programs either prior to or during pregnancy enhances malaria risk. PMID:21345193
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Chanda, Emmanuel; Ameneshewa, Birkinesh; Angula, Hans A; Iitula, Iitula; Uusiku, Pentrina; Trune, Desta; Islam, Quazi M; Govere, John M
2015-08-05
Namibia has made tremendous gains in malaria control and the epidemiological trend of the disease has changed significantly over the past years. In 2010, the country reoriented from the objective of reducing disease morbidity and mortality to the goal of achieving malaria elimination by 2020. This manuscript outlines the processes undertaken in strengthening tactical planning and operational frameworks for vector control to facilitate expeditious malaria elimination in Namibia. The information sources for this study included all available data and accessible archived documentary records on malaria vector control in Namibia. A methodical assessment of published and unpublished documents was conducted via a literature search of online electronic databases, Google Scholar, PubMed and WHO, using a combination of search terms. To attain the goal of elimination in Namibia, systems are being strengthened to identify and clear all infections, and significantly reduce human-mosquito contact. Particularly, consolidating vector control for reducing transmission at the identified malaria foci will be critical for accelerated malaria elimination. Thus, guarding against potential challenges and the need for evidence-based and sustainable vector control instigated the strengthening of strategic frameworks by: adopting the integrated vector management (IVM) strategy; initiating implementation of the global plan for insecticide resistance management (GPIRM); intensifying malaria vector surveillance; improving data collection and reporting systems on DDT; updating the indoor residual spraying (IRS) data collection and reporting tool; and, improving geographical reconnaissance using geographical information system-based satellite imagery. Universal coverage with IRS and long-lasting insecticidal nets, supplemented by larval source management in the context of IVM and guided by vector surveillance coupled with rational operationalization of the GPIRM, will enable expeditious
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Pearce, George W.; Gooden, E. L.; Johnson, Donald R.
1959-01-01
Background information is presented on the development of specifications for 75% DDT water-dispersible powder for use in malaria control programmes supported by the International Cooperation Administration (ICA) of the United States Government. Early difficulties with DDT powders used in these programmes were investigated and it was found that the most critical requirements involved packaging, suspensibility and storage stability. ICA specifications were evolved to meet these requirements. The suspensibility test developed is described, and the importance of inspection of the material procured is discussed. PMID:14431217
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Malaria in India: The Center for the Study of Complex Malaria in India
Das, Aparup; Anvikar, Anupkumar R.; Cator, Lauren J.; Dhiman, Ramesh C.; Eapen, Alex; Mishra, Neelima; Nagpal, Bhupinder N.; Nanda, Nutan; Raghavendra, Kamaraju; Read, Andrew F.; Sharma, Surya K.; Singh, Om P.; Singh, Vineeta; Sinnis, Photini; Srivastava, Harish C.; Sullivan, Steven A.; Sutton, Patrick L.; Thomas, Matthew B.; Carlton, Jane M.; Valecha, Neena
2012-01-01
Malaria is a major public health problem in India and one which contributes significantly to the overall malaria burden in Southeast Asia. The National Vector Borne Disease Control Program of India reported ~1.6 million cases and ~1100 malaria deaths in 2009. Some experts argue that this is a serious underestimation and that the actual number of malaria cases per year is likely between 9 and 50 times greater, with an approximate 13-fold underestimation of malaria-related mortality. The difficulty in making these estimations is further exacerbated by (i) highly variable malaria eco-epidemiological profiles, (ii) the transmission and overlap of multiple Plasmodium species and Anopheles vectors, (iii) increasing antimalarial drug resistance and insecticide resistance, and (iv) the impact of climate change on each of these variables. Simply stated, the burden of malaria in India is complex. Here we describe plans for a Center for the Study of Complex Malaria in India (CSCMi), one of ten International Centers of Excellence in Malaria Research (ICEMRs) located in malarious regions of the world recently funded by the National Institute of Allergy and Infectious Diseases, National Institutes of Health. The CSCMi is a close partnership between Indian and United States scientists, and aims to address major gaps in our understanding of the complexity of malaria in India, including changing patterns of epidemiology, vector biology and control, drug resistance, and parasite genomics. We hope that such a multidisciplinary approach that integrates clinical and field studies with laboratory, molecular, and genomic methods will provide a powerful combination for malaria control and prevention in India. PMID:22142788
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2012-01-01
Background Recently, IMACCESS® developed a new malaria test (VIKIA Malaria Ag Pf/Pan™), based on the detection of falciparum malaria (HRP-2) and non-falciparum malaria (aldolase). Methods The performance of this new malaria rapid diagnostic test (RDT) was assessed using 1,000 febrile patients seeking malaria treatment in four health centres in Cambodia from August to December 2011. The results of the VIKIA Malaria Ag Pf/Pan were compared with those obtained by microscopy, the CareStart Malaria™ RDT (AccessBio®) which is currently used in Cambodia, and real-time PCR (as “gold standard”). Results The best performances of the VIKIA Malaria Ag Pf/Pan™ test for detection of both Plasmodium falciparum and non-P. falciparum were with 20–30 min reading times (sensitivity of 93.4% for P. falciparum and 82.8% for non-P. falciparum and specificity of 98.6% for P. falciparum and 98.9% for non-P. falciparum) and were similar to those for the CareStart Malaria™ test. Conclusions This new RDT performs similarly well as other commercially available tests (especially the CareStart Malaria™ test, used as comparator), and conforms to the World Health Organization’s recommendations for RDT performance. It is a good alternative tool for the diagnosis of malaria in endemic areas. PMID:22920654
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Sharma, V. P.
2012-01-01
Malaria control in India has occupied high priority in health sector consuming major resources of the Central and State governments. Several new initiatives were launched from time to time supported by foreign aids but malaria situation has remained static and worsened in years of good rainfall. At times malaria relented temporarily but returned with vengeance at the local, regional and national level, becoming more resilient by acquiring resistance in the vectors and the parasites. National developments to improve the economy, without health impact assessment, have had adverse consequences by providing enormous breeding grounds for the vectors that have become refractory to interventions. As a result, malaria prospers and its control is in dilemma, as finding additional resources is becoming difficult with the ongoing financial crisis. Endemic countries must contribute to make up the needed resources, if malaria is to be contained. Malaria control requires long term planning, one that will reduce receptivity and vulnerability, and uninterrupted financial support for sustained interventions. While this seems to be a far cry, the environment is becoming more receptive for vectors, and epidemics visit the country diverting major resources in their containment, e.g. malaria, dengue and dengue haemorrhagic fevers, and Chikungunya virus infection. In the last six decades malaria has taken deep roots and diversified into various ecotypes, the control of these ecotypes requires local knowledge about the vectors and the parasites. In this review we outline the historical account of malaria and methods of control that have lifted the national economy in many countries. While battles against malaria should continue at the local level, there is a need for large scale environmental improvement. Global Fund for AIDS, Tuberculosis and Malaria has provided huge funds for malaria control worldwide touching US$ 2 billion in 2011. Unfortunately it is likely to decline to US$ 1
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Sharma, V P
2012-12-01
Malaria control in India has occupied high priority in health sector consuming major resources of the Central and State governments. Several new initiatives were launched from time to time supported by foreign aids but malaria situation has remained static and worsened in years of good rainfall. At times malaria relented temporarily but returned with vengeance at the local, regional and national level, becoming more resilient by acquiring resistance in the vectors and the parasites. National developments to improve the economy, without health impact assessment, have had adverse consequences by providing enormous breeding grounds for the vectors that have become refractory to interventions. As a result, malaria prospers and its control is in dilemma, as finding additional resources is becoming difficult with the ongoing financial crisis. Endemic countries must contribute to make up the needed resources, if malaria is to be contained. Malaria control requires long term planning, one that will reduce receptivity and vulnerability, and uninterrupted financial support for sustained interventions. While this seems to be a far cry, the environment is becoming more receptive for vectors, and epidemics visit the country diverting major resources in their containment, e.g. malaria, dengue and dengue haemorrhagic fevers, and Chikungunya virus infection. In the last six decades malaria has taken deep roots and diversified into various ecotypes, the control of these ecotypes requires local knowledge about the vectors and the parasites. In this review we outline the historical account of malaria and methods of control that have lifted the national economy in many countries. While battles against malaria should continue at the local level, there is a need for large scale environmental improvement. Global Fund for AIDS, Tuberculosis and Malaria has provided huge funds for malaria control worldwide touching US$ 2 billion in 2011. Unfortunately it is likely to decline to US$ 1
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[Malaria situation and evaluation on the control effect in Henan Province during 1990-2005].
Liu, Xue-zhou; Xu, Bian-li
2006-06-01
To analyze malaria situation and evaluate the effect of control program in Henan Province during 1990-2005. Data were collected and analyzed on the measures and effects of malaria control, vector surveillance, blood examination for cases with fever and serological surveillance in the province during 1990-2005. In the 16 years, a total of 802,700 people were given pre-transmission season treatment with chloroquine and primaquine for a radical cure of vivax malaria, chemoprophylaxis was given to 764,300 people at high risk during the transmission season, treatment or presumptive treatment was given to 43,891 cases. 11,216,100 cases with fever were tested and 11,213 (0.10%) were found positive accounting for 29.01% (11 213/338 654) of all malaria cases. A total of 1 332 800 bed nets were treated with insecticide and 1,999 300 people were protected in 1990-1992 and 1996-1999. 34,846 residents including pupils were tested with IFAT in 1990-2000 and 1149 (3.30%) were positive. The parasite rate amongst 71,234 local residents including pupils was 0.40% (286/71,234). The principal transmitting vectors were Anopheles sinensis and An. anthropophagus. The man-biting habit for An. sinensis and An. anthropophagus was 0.0608 and 0.3143 respectively, and the vectorial capacity of An. anthropophagus was 22.4 times higher than that of An. sinensis. In this period, 38,654 malaria cases were reported in the province and the annual malaria incidence was 2.62 per hundred thousand, the lowest annual incidence was in 1992 (0.37 per hundred thousand). 70.05% (27,076/38,654) of these malaria cases were from areas where An. anthropophagus was present. In general, the malaria control activities have been effective and the epidemiological situation kept stable in Henan Province, although in some areas the situation is unstable and outbreak spots or focal epidemics occur.
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Combining fungal biopesticides and insecticide-treated bednets to enhance malaria control.
Hancock, Penelope A
2009-10-01
In developing strategies to control malaria vectors, there is increased interest in biological methods that do not cause instant vector mortality, but have sublethal and lethal effects at different ages and stages in the mosquito life cycle. These techniques, particularly if integrated with other vector control interventions, may produce substantial reductions in malaria transmission due to the total effect of alterations to multiple life history parameters at relevant points in the life-cycle and transmission-cycle of the vector. To quantify this effect, an analytically tractable gonotrophic cycle model of mosquito-malaria interactions is developed that unites existing continuous and discrete feeding cycle approaches. As a case study, the combined use of fungal biopesticides and insecticide treated bednets (ITNs) is considered. Low values of the equilibrium EIR and human prevalence were obtained when fungal biopesticides and ITNs were combined, even for scenarios where each intervention acting alone had relatively little impact. The effect of the combined interventions on the equilibrium EIR was at least as strong as the multiplicative effect of both interventions. For scenarios representing difficult conditions for malaria control, due to high transmission intensity and widespread insecticide resistance, the effect of the combined interventions on the equilibrium EIR was greater than the multiplicative effect, as a result of synergistic interactions between the interventions. Fungal biopesticide application was found to be most effective when ITN coverage was high, producing significant reductions in equilibrium prevalence for low levels of biopesticide coverage. By incorporating biological mechanisms relevant to vectorial capacity, continuous-time vector population models can increase their applicability to integrated vector management.
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Kiware, Samson S; Chitnis, Nakul; Tatarsky, Allison; Wu, Sean; Castellanos, Héctor Manuel Sánchez; Gosling, Roly; Smith, David; Marshall, John M
2017-01-01
Despite great achievements by insecticide-treated nets (ITNs) and indoor residual spraying (IRS) in reducing malaria transmission, it is unlikely these tools will be sufficient to eliminate malaria transmission on their own in many settings today. Fortunately, field experiments indicate that there are many promising vector control interventions that can be used to complement ITNs and/or IRS by targeting a wide range of biological and environmental mosquito resources. The majority of these experiments were performed to test a single vector control intervention in isolation; however, there is growing evidence and consensus that effective vector control with the goal of malaria elimination will require a combination of interventions. We have developed a model of mosquito population dynamic to describe the mosquito life and feeding cycles and to optimize the impact of vector control intervention combinations at suppressing mosquito populations. The model simulations were performed for the main three malaria vectors in sub-Saharan Africa, Anopheles gambiae s.s, An. arabiensis and An. funestus. We considered areas having low, moderate and high malaria transmission, corresponding to entomological inoculation rates of 10, 50 and 100 infective bites per person per year, respectively. In all settings, we considered baseline ITN coverage of 50% or 80% in addition to a range of other vector control tools to interrupt malaria transmission. The model was used to sweep through parameters space to select the best optimal intervention packages. Sample model simulations indicate that, starting with ITNs at a coverage of 50% (An. gambiae s.s. and An. funestus) or 80% (An. arabiensis) and adding interventions that do not require human participation (e.g. larviciding at 80% coverage, endectocide treated cattle at 50% coverage and attractive toxic sugar baits at 50% coverage) may be sufficient to suppress all the three species to an extent required to achieve local malaria elimination
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Kibret, Solomon; Wilson, G Glenn; Tekie, Habte; Petros, Beyene
2014-09-13
Irrigation schemes have been blamed for the increase in malaria in many parts of sub-Saharan Africa. However, proper water management could help mitigate malaria around irrigation schemes in this region. This study investigates the link between irrigation and malaria in Central Ethiopia. Larval and adult mosquitoes were collected fortnightly between November 2009 and October 2010 from two irrigated and two non-irrigated (control) villages in the Ziway area, Central Ethiopia. Daily canal water releases were recorded during the study period and bi-weekly correlation analysis was done to determine relationships between canal water releases and larval/adult vector densities. Blood meal sources (bovine vs human) and malaria sporozoite infection were tested using enzyme-linked immunosorbent assay (ELISA). Monthly malaria data were also collected from central health centre of the study villages. Monthly malaria incidence was over six-fold higher in the irrigated villages than the non-irrigated villages. The number of anopheline breeding habitats was 3.6 times higher in the irrigated villages than the non-irrigated villages and the most common Anopheles mosquito breeding habitats were waterlogged field puddles, leakage pools from irrigation canals and poorly functioning irrigation canals. Larval and adult anopheline densities were seven- and nine-fold higher in the irrigated villages than in the non-irrigated villages, respectively, during the study period. Anopheles arabiensis was the predominant species in the study area. Plasmodium falciparum sporozoite rates of An. arabiensis and Anopheles pharoensis were significantly higher in the irrigated villages than the non-irrigated villages. The annual entomological inoculation rate (EIR) calculated for the irrigated and non-irrigated villages were 34.8 and 0.25 P. falciparum infective bites per person per year, respectively. A strong positive correlation was found between bi-weekly anopheline larval density and canal water
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Das, Ashis; Das Gupta, R K; Friedman, Jed; Pradhan, Madan M; Mohapatra, Charu C; Sandhibigraha, Debakanta
2013-01-29
community perceptions and practices on malaria management. The current community awareness on symptoms of malaria and prevention is fair, yet the prevention and treatment practices are not optimal. Promoting active community involvement and ownership in malaria control and management through strengthening community based organizations would be relevant. Further, timely availability of drugs and commodities at the community level can improve their confidence in the public health system.
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Mosquito Infectivity and Parasitemia after Controlled Human Malaria Infection.
Walk, Jona; van Gemert, Geert-Jan; Graumans, Wouter; Sauerwein, Robert; Bijker, Else M
2018-04-30
Controlled Human Malaria Infection (CHMI) has become an increasingly important tool for the evaluation of drugs and vaccines. Controlled Human Malaria Infection has been demonstrated to be a reproducible model; however, there is some variability in time to onset of parasitemia between volunteers and studies. At our center, mosquitoes infected with Plasmodium falciparum by membrane feeding have variable and high salivary gland sporozoite load (mean 78,415; range 26,500-160,500). To determine whether this load influences parasitemia after CHMI, we analyzed data from 13 studies. We found no correlation between the sporozoite load of a mosquito batch and time to parasitemia or parasite density of first-wave parasitemia. These findings support the use of infected mosquito bite as a reproducible means of inducing P. falciparum infection and suggest that within this range, salivary gland sporozoite load does not influence the stringency of a CHMI.
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PARACHUTING CATS AND CRUSHED EGGS The Controversy Over the Use of DDT to Control Malaria
2008-01-01
The use of DDT to control malaria has been a contentious practice for decades. This controversy centers on concerns over the ecological harm caused by DDT relative to the gains in public health from its use to prevent malaria. Given the World Health Organization's recent policy decisions concerning the use of DDT to control malaria, it is worth reviewing the historical context of DDT use. Ecological concerns focused on evidence that DDT ingestion by predatory birds resulted in eggs with shells so thin they were crushed by adult birds. In addition, DDT spraying to control malaria allegedly resulted in cats being poisoned in some areas, which led to increased rodent populations and, in turn, the parachuting of cats into the highlands of the island of Borneo to kill the rodents, a story that influenced the decision to ban DDT spraying. I focus on this story with the intention of grounding the current debate on lessons from the past. PMID:18799776
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The Value of Information in Decision-Analytic Modeling for Malaria Vector Control in East Africa.
Kim, Dohyeong; Brown, Zachary; Anderson, Richard; Mutero, Clifford; Miranda, Marie Lynn; Wiener, Jonathan; Kramer, Randall
2017-02-01
Decision analysis tools and mathematical modeling are increasingly emphasized in malaria control programs worldwide to improve resource allocation and address ongoing challenges with sustainability. However, such tools require substantial scientific evidence, which is costly to acquire. The value of information (VOI) has been proposed as a metric for gauging the value of reduced model uncertainty. We apply this concept to an evidenced-based Malaria Decision Analysis Support Tool (MDAST) designed for application in East Africa. In developing MDAST, substantial gaps in the scientific evidence base were identified regarding insecticide resistance in malaria vector control and the effectiveness of alternative mosquito control approaches, including larviciding. We identify four entomological parameters in the model (two for insecticide resistance and two for larviciding) that involve high levels of uncertainty and to which outputs in MDAST are sensitive. We estimate and compare a VOI for combinations of these parameters in evaluating three policy alternatives relative to a status quo policy. We find having perfect information on the uncertain parameters could improve program net benefits by up to 5-21%, with the highest VOI associated with jointly eliminating uncertainty about reproductive speed of malaria-transmitting mosquitoes and initial efficacy of larviciding at reducing the emergence of new adult mosquitoes. Future research on parameter uncertainty in decision analysis of malaria control policy should investigate the VOI with respect to other aspects of malaria transmission (such as antimalarial resistance), the costs of reducing uncertainty in these parameters, and the extent to which imperfect information about these parameters can improve payoffs. © 2016 Society for Risk Analysis.
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Noviyanti, Rintis; Coutrier, Farah; Utami, Retno A. S.; Trimarsanto, Hidayat; Tirta, Yusrifar K.; Trianty, Leily; Kusuma, Andreas; Sutanto, Inge; Kosasih, Ayleen; Kusriastuti, Rita; Hawley, William A.; Laihad, Ferdinand; Lobo, Neil; Marfurt, Jutta; Clark, Taane G.; Price, Ric N.; Auburn, Sarah
2015-01-01
Background Outside of Africa, P. falciparum and P. vivax usually coexist. In such co-endemic regions, successful malaria control programs have a greater impact on reducing falciparum malaria, resulting in P. vivax becoming the predominant species of infection. Adding to the challenges of elimination, the dormant liver stage complicates efforts to monitor the impact of ongoing interventions against P. vivax. We investigated molecular approaches to inform the respective transmission dynamics of P. falciparum and P. vivax and how these could help to prioritize public health interventions. Methodology/ Principal Findings Genotype data generated at 8 and 9 microsatellite loci were analysed in 168 P. falciparum and 166 P. vivax isolates, respectively, from four co-endemic sites in Indonesia (Bangka, Kalimantan, Sumba and West Timor). Measures of diversity, linkage disequilibrium (LD) and population structure were used to gauge the transmission dynamics of each species in each setting. Marked differences were observed in the diversity and population structure of P. vivax versus P. falciparum. In Bangka, Kalimantan and Timor, P. falciparum diversity was low, and LD patterns were consistent with unstable, epidemic transmission, amenable to targeted intervention. In contrast, P. vivax diversity was higher and transmission appeared more stable. Population differentiation was lower in P. vivax versus P. falciparum, suggesting that the hypnozoite reservoir might play an important role in sustaining local transmission and facilitating the spread of P. vivax infections in different endemic settings. P. vivax polyclonality varied with local endemicity, demonstrating potential utility in informing on transmission intensity in this species. Conclusions/ Significance Molecular approaches can provide important information on malaria transmission that is not readily available from traditional epidemiological measures. Elucidation of the transmission dynamics circulating in a given
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Ouattara, Amed; Laurens, Matthew B.
2015-01-01
Despite global efforts to control malaria, the illness remains a significant public health threat. Currently, there is no licensed vaccine against malaria, but an efficacious vaccine would represent an important public health tool for successful malaria elimination. Malaria vaccine development continues to be hindered by a poor understanding of antimalarial immunity, a lack of an immune correlate of protection, and the genetic diversity of malaria parasites. Current vaccine development efforts largely target Plasmodium falciparum parasites in the pre-erythrocytic and erythrocytic stages, with some research on transmission-blocking vaccines against asexual stages and vaccines against pregnancy-associated malaria. The leading pre-erythrocytic vaccine candidate is RTS,S, and early results of ongoing Phase 3 testing show overall efficacy of 46% against clinical malaria. The next steps for malaria vaccine development will focus on the design of a product that is efficacious against the highly diverse strains of malaria and the identification of a correlate of protection against disease. PMID:25452593
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Garley, Ashley; Eckert, Erin; Sie, Ali; Ye, Maurice; Malm, Keziah; Afari, Edwin A; Sawadogo, Mamadou; Herrera, Samantha; Ivanovich, Elizabeth; Ye, Yazoume
2016-05-28
Malaria control interventions in most endemic countries have intensified in recent years and so there is a need for a robust monitoring and evaluation (M&E) system to measure progress and achievements. Providing programme and M&E officers with the appropriate skills is a way to strengthen malaria's M&E systems and enhance information use for programmes' implementation. This paper describes a recent effort in capacity strengthening for malaria M&E in sub-Saharan Africa (SSA). From 2010 to 2014, capacity-strengthening efforts consisted of organizing regional in-person workshops for M&E of malaria programmes for Anglophone and Francophone countries in SSA in collaboration with partners from Ghana and Burkina Faso. Open-sourced online courses were also available in English. A post-workshop assessment was conducted after 5 years to assess the effects of these regional workshops and identify gaps in capacity. The regional workshops trained 181 participants from 28 countries from 2010 to 2014. Trained participants were from ministries of health, national malaria control and elimination programmes, non-governmental organizations, and development partners. The average score (%) for participants' knowledge tests increased from pretest to posttest for Anglophone workshops (2011: 59 vs. 76, 2012: 41 vs. 63, 2013: 51 vs. 73; 2014: 50 vs. 74). Similarly, Francophone workshop posttest scores increased, but were lower than Anglophone due to higher scores at pretest. (2011: 70 vs. 76, 2012: 74 vs. 79, 2013: 61 vs. 68; 2014: 64 vs. 75). Results of the post-workshop assessment revealed that participants retained practical M&E knowledge and skills for malaria programs, but there is a need for a module on malaria surveillance adapted to the pre-elimination context. The workshops were successful because of the curriculum content, facilitation quality, and the engagement of partner institutions with training expertise. Results from the post-workshop assessment will guide the curriculum
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Malaria in India: the center for the study of complex malaria in India.
Das, Aparup; Anvikar, Anupkumar R; Cator, Lauren J; Dhiman, Ramesh C; Eapen, Alex; Mishra, Neelima; Nagpal, Bhupinder N; Nanda, Nutan; Raghavendra, Kamaraju; Read, Andrew F; Sharma, Surya K; Singh, Om P; Singh, Vineeta; Sinnis, Photini; Srivastava, Harish C; Sullivan, Steven A; Sutton, Patrick L; Thomas, Matthew B; Carlton, Jane M; Valecha, Neena
2012-03-01
Malaria is a major public health problem in India and one which contributes significantly to the overall malaria burden in Southeast Asia. The National Vector Borne Disease Control Program of India reported ∼1.6 million cases and ∼1100 malaria deaths in 2009. Some experts argue that this is a serious underestimation and that the actual number of malaria cases per year is likely between 9 and 50 times greater, with an approximate 13-fold underestimation of malaria-related mortality. The difficulty in making these estimations is further exacerbated by (i) highly variable malaria eco-epidemiological profiles, (ii) the transmission and overlap of multiple Plasmodium species and Anopheles vectors, (iii) increasing antimalarial drug resistance and insecticide resistance, and (iv) the impact of climate change on each of these variables. Simply stated, the burden of malaria in India is complex. Here we describe plans for a Center for the Study of Complex Malaria in India (CSCMi), one of ten International Centers of Excellence in Malaria Research (ICEMRs) located in malarious regions of the world recently funded by the National Institute of Allergy and Infectious Diseases, National Institutes of Health. The CSCMi is a close partnership between Indian and United States scientists, and aims to address major gaps in our understanding of the complexity of malaria in India, including changing patterns of epidemiology, vector biology and control, drug resistance, and parasite genomics. We hope that such a multidisciplinary approach that integrates clinical and field studies with laboratory, molecular, and genomic methods will provide a powerful combination for malaria control and prevention in India. Copyright © 2011 Elsevier B.V. All rights reserved.
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Ruiz, Daniel; Poveda, Germán; Vélez, Iván D; Quiñones, Martha L; Rúa, Guillermo L; Velásquez, Luz E; Zuluaga, Juan S
2006-01-01
Background Malaria has recently re-emerged as a public health burden in Colombia. Although the problem seems to be climate-driven, there remain significant gaps of knowledge in the understanding of the complexity of malaria transmission, which have motivated attempts to develop a comprehensive model. Methods The mathematical tool was applied to represent Plasmodium falciparum malaria transmission in two endemic-areas. Entomological exogenous variables were estimated through field campaigns and laboratory experiments. Availability of breeding places was included towards representing fluctuations in vector densities. Diverse scenarios, sensitivity analyses and instabilities cases were considered during experimentation-validation process. Results Correlation coefficients and mean square errors between observed and modelled incidences reached 0.897–0.668 (P > 0.95) and 0.0002–0.0005, respectively. Temperature became the most relevant climatic parameter driving the final incidence. Accordingly, malaria outbreaks are possible during the favourable epochs following the onset of El Niño warm events. Sporogonic and gonotrophic cycles showed to be the entomological key-variables controlling the transmission potential of mosquitoes' population. Simulation results also showed that seasonality of vector density becomes an important factor towards understanding disease transmission. Conclusion The model constitutes a promising tool to deepen the understanding of the multiple interactions related to malaria transmission conducive to outbreaks. In the foreseeable future it could be implemented as a tool to diagnose possible dynamical patterns of malaria incidence under several scenarios, as well as a decision-making tool for the early detection and control of outbreaks. The model will be also able to be merged with forecasts of El Niño events to provide a National Malaria Early Warning System. PMID:16882349
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International Advocacy against DDT and Other Public Health Insecticides for Malaria Control
2011-01-19
compared with controls. This was true across all eight countries. Broad use of antimalarial drugs was the primary method of malaria suppression in...eight countries. Broad use of antimalarial drugs was the primary method of malaria suppression in the eight countries, but this method was not a GEF...Available evidence suggests the NMCPs did their work regardless of the presence or absence of GEF project personnel. Thus, antimalarial treatment (the
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Malaria in the WHO Southeast Asia region.
Kondrashin, A V
1992-09-01
Malaria endemic countries in the southeast Asia region include Bangladesh, Bhutan, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka, and Thailand. Population movement and rapid urbanization, both largely caused by unemployment, and environmental deterioration change the malaria pattern. They also increase the incidence of drug-resistant malaria, especially resistance to 4-aminoquinolines. In India, Plasmodium falciparum is linked to the density and distribution of tribals, and, in southern Thailand, rubber tappers have the highest malaria incidence rate (46.29%). Since the population is young and the young are highly sensitive to malaria infection, the region has low community immunity. High malaria priority areas are forests, forested hills, forest fringe areas, developmental project sites, and border areas. High risk groups include infants, young children, pregnant women, and mobile population groups. Malaria incidence is between 2.5-2.8 million cases, and the slide positivity rate is about 3%. P. falciparum constitutes 40% for all malaria cases. In 1988 in India, there were 222 malaria deaths. Malaria is the 7th most common cause of death in Thailand. 3 of the 19 Anopheline species are resistant to at least 1 insecticide, particularly DDT. Posteradication epidemics surfaced in the mid-1970s. Malaria control programs tend to use the primary health care and integration approach to malaria control. Antiparasite measures range from a single-dose of an antimalarial to mass drug administration. Residual spraying continues to be the main strategy of vector control. Some other vector control measures are fish feeding on mosquito larvae, insecticide impregnated mosquito nets, and repellents. Control programs also have health education activities. India allocates the highest percentage of its total health budget to malaria control (21.54%). Few malariology training programs exist in the region. Slowly processed surveillance data limit the countries' ability to
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Progress in malaria vector control.
Pant, C P; Rishikesh, N; Bang, Y H; Smith, A
1981-01-01
Malaria control, except in tropical Africa, will probably continue to be based to a large extent on the use of insecticides for many years. However, the development of resistance to insecticides in the vectors has caused serious difficulties and it is necessary to change the strategy of insecticide use to maximize their efficacy. A thorough knowledge of the ecology and behaviour of each vector species is required before the control strategy can be adapted to different epidemiological situations. The behavioural differences between sibling species have been recognized for several years, but study of this problem has recently been simplified by improved means of identification that involve chromosomal banding patterns and electrophoretic analysis. Behavioural differences have also been associated with certain chromosomal rearrangements.New records of insecticide resistance among anophelines continue to appear and the impact of this on antimalaria operations has been seriously felt in Central America (multi-resistance in Anopheles albimanus), Turkey (A. sacharovi), India and several Asian countries (A. culicifacies and A. stephensi), and some other countries. Work continues on the screening and testing of newer insecticides that can be used as alternatives, but DDT, malathion, temephos, fenitrothion, and propoxur continue to be used as the main insecticides in many malaria control projects. The search for simpler and innovative approaches to insecticide application also continues.Biological control of vectors is receiving increased attention, as it could become an important component of integrated vector control strategies, and most progress has been made with the spore-forming bacterium, serotype H-14 of Bacillus thuringiensis. Larvivorous fish such as Gambusia spp. and Poecilia spp. continue to be used in some programmes.Application of environmental management measures, such as source reduction, source elimination, flushing of drainage and irrigation channels, and
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Wangdi, Kinley; Banwell, Cathy; Gatton, Michelle L; Kelly, Gerard C; Namgay, Rinzin; Clements, Archie C A
2016-05-01
The number of malaria cases has fallen in Bhutan in the past two decades, and the country has a goal of complete elimination of malaria by 2016. The aims of this study are to ascertain the trends and burden of malaria, the costs of intensified control activities, the main donors of funding for the control activities, and the costs of different preventive measures in the pre-elimination phase (2006-14) in Bhutan. We undertook a descriptive analysis of malaria surveillance data from 2006 to 2014, using data from the Vector-borne Disease Control Programme (VDCP) run by the Department of Public Health of Bhutan's Ministry of Health. Malaria morbidity and mortality in local Bhutanese people and foreign nationals were analysed. The cost of different control and preventive measures were calculated, and the average numbers of long-lasting insecticidal nests per person were estimated. A total of 5491 confirmed malaria cases occurred in Bhutan between 2006 and 2014. By 2013, there was an average of one long-lasting insecticidal net for every 1·51 individuals. The cost of procuring long-lasting insecticidal nets accounted for more than 90% of the total cost of prevention measures. The Global Fund to Fight AIDS, Tuberculosis and Malaria was the main international donor, accounting for more than 80% of the total funds. The malaria burden in Bhutan decreased significantly during the study period with high coverage of long-lasting insecticidal nets. The foreseeable challenges that require national attention to maintain a malaria-free status after elimination are importation of malaria, especially from India; continued protection of the population in endemic districts through complete coverage with long-lasting insecticidal nets and indoor residual spraying; and exploration of local funding modalities post-elimination in the event of a reduction in international funding. None. Copyright © 2016 Wangdi et al. Open Access article distributed under the terms of CC BY. Published by
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2013-01-01
Background As successful malaria control programmes move towards elimination, they must identify residual transmission foci, target vector control to high-risk areas, focus on both asymptomatic and symptomatic infections, and manage importation risk. High spatial and temporal resolution maps of malaria risk can support all of these activities, but commonly available malaria maps are based on parasite rate, a poor metric for measuring malaria at extremely low prevalence. New approaches are required to provide case-based risk maps to countries seeking to identify remaining hotspots of transmission while managing the risk of transmission from imported cases. Methods Household locations and travel histories of confirmed malaria patients during 2011 were recorded through routine surveillance by the Swaziland National Malaria Control Programme for the higher transmission months of January to April and the lower transmission months of May to December. Household locations for patients with no travel history to endemic areas were compared against a random set of background points sampled proportionate to population density with respect to a set of variables related to environment, population density, vector control, and distance to the locations of identified imported cases. Comparisons were made separately for the high and low transmission seasons. The Random Forests regression tree classification approach was used to generate maps predicting the probability of a locally acquired case at 100 m resolution across Swaziland for each season. Results Results indicated that case households during the high transmission season tended to be located in areas of lower elevation, closer to bodies of water, in more sparsely populated areas, with lower rainfall and warmer temperatures, and closer to imported cases than random background points (all p < 0.001). Similar differences were evident during the low transmission season. Maps from the fit models suggested better predictive
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Ayi, Irene; Nonaka, Daisuke; Adjovu, Josiah K; Hanafusa, Shigeki; Jimba, Masamine; Bosompem, Kwabena M; Mizoue, Tetsuya; Takeuchi, Tsutomu; Boakye, Daniel A; Kobayashi, Jun
2010-04-18
School children have been increasingly recognized as health messengers for malaria control. However, little evidence is available. The objective of this study was to determine the impact of school-based malaria education intervention on school children and community adults. This study was conducted in the Dangme-East district of the Greater Accra Region, Ghana, between 2007 and 2008. Trained schoolteachers designed participatory health education activities and led school children to disseminate messages related to malaria control to their communities. Three schools and their respective communities were chosen for the study and assigned to an intervention group (one school) and a control group (two schools). Questionnaire-based interviews and parasitological surveys were conducted before and after the intervention, with the intervention group (105 children, 250 community adults) and the control group (81 children, 133 community adults). Chi-square and Fisher's Exact tests were used to analyse differences in knowledge, practices, and parasite prevalence between pre- and post-intervention. After the intervention, the misperception that malaria has multiple causes was significantly improved, both among children and community adults. Moreover, the community adults who treated a bed net with insecticide in the past six months, increased from 21.5% to 50.0% (p < 0.001). Parasite prevalence in school children decreased from 30.9% to 10.3% (p = 0.003). These positive changes were observed only in the intervention group. This study suggests that the participatory health education intervention contributed to the decreased malaria prevalence among children. It had a positive impact not only on school children, but also on community adults, through the improvement of knowledge and practices. This strategy can be applied as a complementary approach to existing malaria control strategies in West African countries where school health management systems have been strengthened.
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Spatial trend, environmental and socioeconomic factors associated with malaria prevalence in Chennai
2014-01-01
Background Urban malaria is considered to be one of the most significant infectious diseases due to varied socioeconomic problems especially in tropical countries like India. Among the south Indian cities, Chennai is endemic for malaria. The present study aimed to identify the hot spots of malaria prevalence and the relationship with other factors in Chennai during 2005-2011. Methods Data on zone-wise and ward-wise monthly malaria positive cases were collected from the Vector Control Office, Chennai Corporation, for the year 2005 to 2011 and verified using field data. This data was used to calculate the prevalence among thousand people. Hotspot analysis for all the years in the study period was done to observe the spatial trend. Association of environmental factors like altitude, population density and climatic variables was assessed using ArcGIS 9.3 version and SPSS 11.5. Pearson’s correlation of climate parameters at 95% and 99% was considered to be the most significant. Social parameters of the highly malaria prone region were evaluated through a structured random questionnaire field survey. Results Among the ten zones of Chennai Corporation, Basin Bridge zone showed high malaria prevalence during the study period. The ‘hotspot’ analysis of malaria prevalence showed the emergence of newer hotspots in the Adyar zone. These hotspots of high prevalence are places of moderately populated and moderately elevated areas. The prevalence of malaria in Chennai could be due to rainfall and temperature, as there is a significant correlation with monthly rainfall and one month lag of monthly mean temperature. Further it has been observed that the socioeconomic status of people in the malaria hotspot regions and unhygienic living conditions were likely to aggravate the malaria problem. Conclusion Malaria hotspots will be the best method to use for targeting malaria control activities. Proper awareness and periodical monitoring of malaria is one of the quintessential
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2014-01-01
Background Mass insecticide treated bed net (ITN) deployment, and its associated coverage of populations at risk, had “pushed” a decline in malaria transmission. However, it is unknown whether malaria control is being enhanced by zooprophylaxis, i.e., mosquitoes diverted to feed on hosts different from humans, a phenomenon that could further reduce malaria entomological transmission risk in areas where livestock herding is common. Methods Between May and July 2009, we collected mosquitoes in 104 houses from three neighboring villages with high ITN coverage (over 80%), along Lake Victoria. We also performed a census of livestock in the area and georeferenced tethering points for all herds, as well as, mosquito larval habitats. Bloodmeal contents from sampled mosquitoes were analyzed, and each mosquito was individually tested for malaria sporozoite infections. We then evaluated the association of human density, ITN use, livestock abundance and larval habitats with mosquito abundance, bloodfeeding on humans and malaria sporozoite rate using generalized linear mixed effects models. Results We collected a total of 8123 mosquitoes, of which 1664 were Anopheles spp. malaria vectors over 295 household spray catches. We found that vector household abundance was mainly driven by the number of householders (P < 0.05), goats/sheep tethered around the house (P < 0.05) and ITNs, which halved mosquito abundance (P < 0.05). In general, similar patterns were observed for Anopheles arabiensis, but not An. gambiae s.s. and An. funestus s.s., whose density did not increase with the presence of livestock animals. Feeding on humans significantly increased in all species with the number of householders (P < 0.05), and only significantly decreased for An. arabiensis in the presence of cattle (P < 0.05). Only 26 Anopheles spp. vectors had malaria sporozoites with the sporozoite rate significantly decreasing as the proportion of cattle feeding mosquitoes increased
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Prosper, Olivia; Ruktanonchai, Nick; Martcheva, Maia
2014-07-21
Following over two decades of research, the malaria vaccine candidate RTS,S has reached the final stages of vaccine trials, demonstrating an efficacy of roughly 50% in young children. Regions with high malaria prevalence tend to have high levels of naturally acquired immunity (NAI) to severe malaria; NAI is caused by repeated exposure to infectious bites and results in large asymptomatic populations. To address concerns about how these vaccines will perform in regions with existing NAI, we developed a simple malaria model incorporating vaccination and NAI. Typically, if the basic reproduction number (R0) for malaria is greater than unity, the disease will persist; otherwise, the disease will become extinct. However, analysis of this model revealed that NAI, compounded by a subpopulation with only partial protection to malaria, may render vaccination efforts ineffective and potentially detrimental to malaria control, by increasing R0 and increasing the likelihood of malaria persistence even when R0<1. The likelihood of this scenario increases when non-immune infected individuals are treated disproportionately compared with partially immune individuals - a plausible scenario since partially immune individuals are more likely to be asymptomatically infected. Consequently, we argue that active case-detection of asymptomatic infections is a critical component of an effective malaria control program. We then investigated optimal vaccination and bednet control programs under two endemic settings with varying levels of naturally acquired immunity: a typical setting under which prevalence decays when R0<1, and a setting in which subthreshold endemic equilibria exist. A qualitative comparison of the optimal control results under the first setting revealed that the optimal policy differs depending on whether the goal is to reduce total morbidity, or to reduce clinical infections. Furthermore, this comparison dictates that control programs should place less effort in
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Microbial larvicides for malaria control in The Gambia
Majambere, Silas; Lindsay, Steven W; Green, Clare; Kandeh, Balla; Fillinger, Ulrike
2007-01-01
Background Mosquito larval control may prove to be an effective tool for incorporating into integrated vector management (IVM) strategies for reducing malaria transmission. Here the efficacy of microbial larvicides against Anopheles gambiae s.l. was tested in preparation for a large-scale larviciding programme in The Gambia. Methods The impact of water-dispersible (WDG) and corn granule (CG) formulations of commercial Bacillus sphaericus strain 2362 (Bs; VectoLex®) and Bacillus thuringiensis var.israelensis strain AM65-52 (Bti; VectoBac®) on larval development were tested under laboratory and field conditions to (1) identify the susceptibility of local vectors, (2) evaluate the residual effect and re-treatment intervals, (3) test the effectiveness of the microbials under operational application conditions and (4) develop a method for large-scale application. Results The major malaria vectors were highly susceptible to both microbials. The lethal concentration (LC) to kill 95% of third instar larvae of Anopheles gambiae s.s. after 24 hours was 0.023 mg/l (14.9 BsITU/l) for Bs WDG and 0.132 mg/l (396 ITU/l) for Bti WDG. In general Bs had little residual effect under field conditions even when the application rate was 200 times greater than the LC95. However, there was a residual effect up to 10 days in standardized field tests implemented during the dry season. Both microbials achieved 100% mortality of larvae 24–48 hours post-application but late instar larvae were detected 4 days after treatment. Pupae development was reduced by 94% (95% Confidence Interval = 90.8–97.5%) at weekly re-treatment intervals. Field tests showed that Bs had no residual activity against anopheline larvae. Both microbials provided complete protection when applied weekly. The basic training of personnel in identification of habitats, calibration of application equipment and active larviciding proved to be successful and achieved full coverage and control of mosquito larvae for three
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Thera, Mahamadou A.; Doumbo, Ogobara K.; Coulibaly, Drissa; Diallo, Dapa A.; Kone, Abdoulaye K.; Guindo, Ando B.; Traore, Karim; Dicko, Alassane; Sagara, Issaka; Sissoko, Mahamadou S.; Baby, Mounirou; Sissoko, Mady; Diarra, Issa; Niangaly, Amadou; Dolo, Amagana; Daou, Modibo; Diawara, Sory I.; Heppner, D. Gray; Stewart, V. Ann; Angov, Evelina; Bergmann-Leitner, Elke S.; Lanar, David E.; Dutta, Sheetij; Soisson, Lorraine; Diggs, Carter L.; Leach, Amanda; Owusu, Alex; Dubois, Marie-Claude; Cohen, Joe; Nixon, Jason N.; Gregson, Aric; Takala, Shannon L.; Lyke, Kirsten E.; Plowe, Christopher V.
2008-01-01
Background The objective was to evaluate the safety, reactogenicity and immunogenicity of the AMA-1-based blood-stage malaria vaccine FMP2.1/AS02A in adults exposed to seasonal malaria. Methodology/Principal Findings A phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02A is a recombinant protein (FMP2.1) based on apical membrane antigen-1 (AMA-1) from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert). Sixty healthy, malaria-experienced adults aged 18–55 y were recruited into 2 cohorts and randomized to receive either a half dose or full dose of the malaria vaccine (FMP2.1 25 µg/AS02A 0.25 mL or FMP2.1 50 µg/AS02A 0.5 mL) or rabies vaccine given in 3 doses at 0, 1 and 2 mo, and were followed for 1 y. Solicited symptoms were assessed for 7 d and unsolicited symptoms for 30 d after each vaccination. Serious adverse events were assessed throughout the study. Titers of anti-AMA-1 antibodies were measured by ELISA and P. falciparum growth inhibition assays were performed on sera collected at pre- and post-vaccination time points. Transient local pain and swelling were common and more frequent in both malaria vaccine dosage groups than in the comparator group. Anti-AMA-1 antibodies increased significantly in both malaria vaccine groups, peaking at nearly 5-fold and more than 6-fold higher than baseline in the half-dose and full-dose groups, respectively. Conclusion/Significance The FMP2.1/AS02A vaccine had a good safety profile, was well-tolerated, and was highly immunogenic in malaria-exposed adults. This malaria vaccine is being evaluated in Phase 1 and 2 trials in children at this site. Trial Registration ClinicalTrials.gov NCT00308061 PMID:18213374
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Killeen, G F; McKenzie, F E; Foy, B D; Schieffelin, C; Billingsley, P F; Beier, J C
2000-05-01
We have used a relatively simple but accurate model for predicting the impact of integrated transmission control on the malaria entomologic inoculation rate (EIR) at four endemic sites from across sub-Saharan Africa and the southwest Pacific. The simulated campaign incorporated modestly effective vaccine coverage, bed net use, and larval control. The results indicate that such campaigns would reduce EIRs at all four sites by 30- to 50-fold. Even without the vaccine, 15- to 25-fold reductions of EIR were predicted, implying that integrated control with a few modestly effective tools can meaningfully reduce malaria transmission in a range of endemic settings. The model accurately predicts the effects of bed nets and indoor spraying and demonstrates that they are the most effective tools available for reducing EIR. However, the impact of domestic adult vector control is amplified by measures for reducing the rate of emergence of vectors or the level of infectiousness of the human reservoir. We conclude that available tools, including currently neglected methods for larval control, can reduce malaria transmission intensity enough to alleviate mortality. Integrated control programs should be implemented to the fullest extent possible, even in areas of intense transmission, using simple models as decision-making tools. However, we also conclude that to eliminate malaria in many areas of intense transmission is beyond the scope of methods which developing nations can currently afford. New, cost-effective, practical tools are needed if malaria is ever to be eliminated from highly endemic areas.
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2013-01-01
Background Long-lasting insecticide treated nets (LLINs) and indoor residual house spraying (IRS) are the main interventions for the control of malaria vectors in Zanzibar. The aim of the present study was to assess the susceptibility status of malaria vectors against the insecticides used for LLINs and IRS and to determine the durability and efficacy of LLINs on the island. Methods Mosquitoes were sampled from Pemba and Unguja islands in 2010–2011 for use in WHO susceptibility tests. One hundred and fifty LLINs were collected from households on Unguja, their physical state was recorded and then tested for efficacy as well as total insecticide content. Results Species identification revealed that over 90% of the Anopheles gambiae complex was An. arabiensis with a small number of An. gambiae s.s. and An. merus being present. Susceptibility tests showed that An. arabiensis on Pemba was resistant to the pyrethroids used for LLINs and IRS. Mosquitoes from Unguja Island, however, were fully susceptible to all pyrethroids tested. A physical examination of 150 LLINs showed that two thirds were damaged after only three years in use. All used nets had a significantly lower (p < 0.001) mean permethrin concentration of 791.6 mg/m2 compared with 944.2 mg/m2 for new ones. Their efficacy decreased significantly against both susceptible An. gambiae s.s. colony mosquitoes and wild-type mosquitoes from Pemba after just six washes (p < 0.001). Conclusion The sustainability of the gains achieved in malaria control in Zanzibar is seriously threatened by the resistance of malaria vectors to pyrethroids and the short-lived efficacy of LLINs. This study has revealed that even in relatively well-resourced and logistically manageable places like Zanzibar, malaria elimination is going to be difficult to achieve with the current control measures. PMID:23537463
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2012-01-01
Background Ensuring the quality of malaria medicines is crucial in working toward malaria control and eventual elimination. Unlike other validated tests that can assess all critical quality attributes, which is the standard for determining the quality of medicines, basic tests are significantly less expensive, faster, and require less skilled labour; yet, these tests provide reproducible data and information on several critical quality attributes, such as identity, purity, content, and disintegration. Visual and physical inspection also provides valuable information about the manufacturing and the labelling of medicines, and in many cases this inspection is sufficient to detect counterfeit medicines. The Promoting the Quality of Medicines (PQM) programme has provided technical assistance to Amazon Malaria Initiative (AMI) countries to implement the use of basic tests as a key screening mechanism to assess the quality of malaria medicines available to patients in decentralized regions. Methods Trained personnel from the National Malaria Control Programmes (NMCPs), often in collaboration with country’s Official Medicine Control Laboratory (OMCL), developed country- specific protocols that encompassed sampling methods, sample analysis, and data reporting. Sampling sites were selected based on malaria burden, accessibility, and geographical location. Convenience sampling was performed and countries were recommended to store the sampled medicines under conditions that did not compromise their quality. Basic analytical tests, such as disintegration and thin layer chromatography (TLC), were performed utilizing a portable mini-laboratory. Results Results were originally presented at regional meetings in a non-standardized format that lacked relevant medicines information. However, since 2008 information has been submitted utilizing a template specifically developed by PQM for that purpose. From 2005 to 2010, the quality of 1,663 malaria medicines from seven AMI countries
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Yeboah-Antwi, Kojo; Pilingana, Portipher; Macleod, William B.; Semrau, Katherine; Siazeele, Kazungu; Kalesha, Penelope; Hamainza, Busiku; Seidenberg, Phil; Mazimba, Arthur; Sabin, Lora; Kamholz, Karen; Thea, Donald M.; Hamer, Davidson H.
2010-01-01
Background Pneumonia and malaria, two of the leading causes of morbidity and mortality among children under five in Zambia, often have overlapping clinical manifestations. Zambia is piloting the use of artemether-lumefantrine (AL) by community health workers (CHWs) to treat uncomplicated malaria. Valid concerns about potential overuse of AL could be addressed by the use of malaria rapid diagnostics employed at the community level. Currently, CHWs in Zambia evaluate and treat children with suspected malaria in rural areas, but they refer children with suspected pneumonia to the nearest health facility. This study was designed to assess the effectiveness and feasibility of using CHWs to manage nonsevere pneumonia and uncomplicated malaria with the aid of rapid diagnostic tests (RDTs). Methods and Findings Community health posts staffed by CHWs were matched and randomly allocated to intervention and control arms. Children between the ages of 6 months and 5 years were managed according to the study protocol, as follows. Intervention CHWs performed RDTs, treated test-positive children with AL, and treated those with nonsevere pneumonia (increased respiratory rate) with amoxicillin. Control CHWs did not perform RDTs, treated all febrile children with AL, and referred those with signs of pneumonia to the health facility, as per Ministry of Health policy. The primary outcomes were the use of AL in children with fever and early and appropriate treatment with antibiotics for nonsevere pneumonia. A total of 3,125 children with fever and/or difficult/fast breathing were managed over a 12-month period. In the intervention arm, 27.5% (265/963) of children with fever received AL compared to 99.1% (2066/2084) of control children (risk ratio 0.23, 95% confidence interval 0.14–0.38). For children classified with nonsevere pneumonia, 68.2% (247/362) in the intervention arm and 13.3% (22/203) in the control arm received early and appropriate treatment (risk ratio 5.32, 95
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Optimal Control of Malaria Transmission using Insecticide Treated Nets and Spraying
NASA Astrophysics Data System (ADS)
Athina, D.; Bakhtiar, T.; Jaharuddin
2017-03-01
In this paper, we consider a model of the transmission of malaria which was developed by Silva and Torres equipped with two control variables, namely the use of insecticide treated nets (ITN) to reduce the number of human beings infected and spraying to reduce the number of mosquitoes. Pontryagin maximum principle was applied to derive the differential equation system as optimality conditions which must be satisfied by optimal control variables. The Mangasarian sufficiency theorem shows that Pontryagin maximum principle is necessary as well as sufficient conditions for optimization problem. The 4th-order Runge Kutta method was then performed to solve the differential equations system. The numerical results show that both controls given at once can reduce the number of infected individuals as well as the number of mosquitoes which reduce the impact of malaria transmission.
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Couto AA; Calvosa, V S; Lacerda, R; Castro, F; Santa Rosa, E; Nascimento, J M
2001-01-01
This paper reports on the epidemiological characterization of malaria following implementation of a program to control the endemic in a gold-mining area in northern Amapá State. The study focuses on total malaria cases in Amapá and the impact of the disease on the population, as represented by the Mineração Novo Astro S/A company and its employees as well as the community of Vila de Lourenço in the municipality of Calçoene, and adjacent gold miners. The effect of control measures in the program area is indicated by a significant reduction in malaria incidence and malaria-related morbidity and mortality. The importance of participation by private enterprise is emphasized, particularly in large projects for the control of endemic diseases (notably malaria) in the Amazon Region.
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Plasmodium vivax Hospitalizations in a Monoendemic Malaria Region: Severe Vivax Malaria?
Quispe, Antonio M.; Pozo, Edwar; Guerrero, Edith; Durand, Salomón; Baldeviano, G. Christian; Edgel, Kimberly A.; Graf, Paul C. F.; Lescano, Andres G.
2014-01-01
Severe malaria caused by Plasmodium vivax is no longer considered rare. To describe its clinical features, we performed a retrospective case control study in the subregion of Luciano Castillo Colonna, Piura, Peru, an area with nearly exclusive vivax malaria transmission. Severe cases and the subset of critically ill cases were compared with a random set of uncomplicated malaria cases (1:4). Between 2008 and 2009, 6,502 malaria cases were reported, including 106 hospitalized cases, 81 of which fit the World Health Organization definition for severe malaria. Of these 81 individuals, 28 individuals were critically ill (0.4%, 95% confidence interval = 0.2–0.6%) with severe anemia (57%), shock (25%), lung injury (21%), acute renal failure (14%), or cerebral malaria (11%). Two potentially malaria-related deaths occurred. Compared with uncomplicated cases, individuals critically ill were older (38 versus 26 years old, P < 0.001), but similar in other regards. Severe vivax malaria monoinfection with critical illness is more common than previously thought. PMID:24752683
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2012-01-01
Background Malaria and anaemia (Haemoglobin <11 g/dl) remain frequent in tropical regions and are closely associated. Although anaemia aetiologies are known to be multi-factorial, most studies in malaria endemic areas have been confined to analysis of possible associations between anaemia and individual factors such as malaria. A case control study involving children aged from 1 to 10 years was conducted to assess some assumed contributors to anaemia in the area of Bonconto Health post in Senegal. Methods Study participants were randomly selected from a list of children who participated in a survey in December 2010. Children aged from 1 to 10 years with haemoglobin level below 11 g/dl represented cases (anaemic children). Control participants were eligible if of same age group and their haemoglobin level was >= 11 g/dl. For each participant, a physical examination was done and anthropometric data collected prior to a biological assessment which included: malaria parasitaemia infection, intestinal worm carriage, G6PD deficiency, sickle cell disorders, and alpha-talassaemia. Results Three hundred and fifty two children < 10 years of age were enrolled (176 case and 176 controls). In a logistic regression analysis, anaemia was significantly associated with malaria parasitaemia (aOR=5.23, 95%CI[1.1-28.48]), sickle cell disorders (aOR=2.89, 95%CI[1,32-6.34]), alpha-thalassemia (aOR=1.82, 95%CI[1.2-3.35]), stunting (aOR=3.37, 95%CI[1.93-5.88], age ranged from 2 to 4 years (aOR=0.13, 95%CI[0.05-0.31]) and age > 5 years (aOR=0.03, 95%CI[0.01-0.08]). Stratified by age group, anaemia was significantly associated with stunting in children less than 5 years (aOR=3.1 95%CI[1.4 – 6.8]), with, sickle cell disorders (aOR=3.5 95%CI [1.4 – 9.0]), alpha-thalassemia (or=2.4 95%CI[1.1–5.3]) and stunting (aOR=3.6 95%CI [1.6–8.2]) for children above 5 years. No association was found between G6PD deficiency, intestinal worm carriage and children’s gender. Conclusion Malaria
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MEDSAT - A remote sensing satellite for malaria early warning and control
NASA Technical Reports Server (NTRS)
Vesecky, John; Slawski, James; Stottlemeyer, Bret; De La Sierra, Ruben; Daida, Jason; Wood, Byron; Lawless, James
1992-01-01
A remote sensing, medical satellite (MEDSAT) aids in the control of carrier (vector) borne disease. The prototype design is a light satellite to test for control of malaria. The design features a 340-kg satellite with visual/IR and SAR sensors in a low inclination orbit observing a number of worldwide test sites. The approach is to use four-band visual/IR and dual-polarized L-band SAR images obtained from MEDSAT in concert with in-situ data to estimate the temporal and spatial variations of malaria risk. This allows public health resources to focus on the most vulnerable areas at the appropriate time. It is concluded that a light-satellite design for a MEDSAT satellite with a Pegasus launch is feasible.
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Malaria epidemiology in Lihir Island, Papua New Guinea
2013-01-01
Background Plasmodium vivax and Plasmodium falciparum malaria remain highly endemic in the Pacific Islands including Lihir Island, Papua New Guinea. Lihir Gold Limited is conducting mining activities and funded an integrated vector control intervention within the villages surrounding the mine. The aim of this study was to assess the impact of such programme by comparing the epidemiological trends of malaria in different parts of the island. Methods Two cross-sectional surveys were conducted before and after the intervention (2006–2010) to determine malaria prevalence in mine-impact (MI) and non-MI areas. Incidence of malaria was estimated for the Lihir Medical Centre catchment area using island population denominators and a health-centre passive case detection ongoing from 2006–2011. Results A total of 2,264 and 1,653 children < 15 were surveyed in the cross-sectional studies. The prevalence of any malaria parasitaemia initially was 31.5% in MI areas and, 34.9% in non-MI (POR 1.17; 95 CI 0.97 – 1.39). After four years there was a significant reduction in prevalence in the MI areas (5.8%; POR 0.13, 95 CI 0.09–0.20), but reduction was less marked in non-MI areas (26.9%; POR 0.69, 95 CI 0.58-0.81). 28,747 patients were included in the evaluation of incidence trends and overall malaria in local Lihirian population in MI areas declined over time, while it remained at similar high levels among migrants. The age-incidence analysis showed that for each higher age range the malaria incidence declines compared to that of the previous stratum. Conclusions There was a substantial reduction in prevalence and incidence rates of both P. vivax and P. falciparum in the mining area following implementation of a malaria control intervention, which was not seen in the area outside the mining activities. PMID:23497296
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Liu, Xue; Culleton, Richard; Tao, Li; Xia, Hui; Gao, Qi
2014-01-01
Abstract Background Congenital malaria, in which infants are directly infected with malaria parasites from their mother prior to or during birth, is a potentially life-threatening condition that occurs at relatively low rates in malaria-endemic regions. It is recognized as a serious problem in Plasmodium falciparum–endemic sub-Saharan Africa, where recent data suggests that it is more common than previously believed. In such regions where malaria transmission is high, neonates may be protected from disease caused by congenital malaria through the transfer of maternal antibodies against the parasite. However, in low P. vivax–endemic regions, immunity to vivax malaria is low; thus, there is the likelihood that congenital vivax malaria poses a more significant threat to newborn health. Malaria had previously been a major parasitic disease in China, and congenital malaria case reports in Chinese offer valuable information for understanding the risks posed by congenital malaria to neonatal health. As most of the literature documenting congenital malaria cases in China are written in Chinese and therefore are not easily accessible to the global malaria research community, we have undertaken an extensive review of the Chinese literature on this subject. Methods/Principal Findings Here, we reviewed congenital malaria cases from three major searchable Chinese journal databases, concentrating on data from 1915 through 2011. Following extensive screening, a total of 104 cases of congenital malaria were identified. These cases were distributed mainly in the eastern, central, and southern regions of China, as well as in the low-lying region of southwest China. The dominant species was P. vivax (92.50%), reflecting the malaria parasite species distribution in China. The leading clinical presentation was fever, and other clinical presentations were anaemia, jaundice, paleness, diarrhoea, vomiting, and general weakness. With the exception of two cases, all patients were cured
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Liu, Yao-Bao; Cao, Jun; Zhou, Hua-Yun; Wang, Wei-Ming; Cao, Yuan-Yuan; Gao, Qi
2013-02-01
To analyze the epidemiological characteristics of overseas imported malaria in Jiangsu Province and explore the strategies and priorities in prevention and control, so as to provide the evidence for improving the diagnosis, treatment and management of imported malaria. The data of overseas imported malaria as well as the case epidemiological investigation in Jiangsu Province from July 18, 2011 to June 30, 2012 were collected and analyzed descriptively for the species composition, original countries, population distribution, regional distribution, onset time, diagnosis and treatment, channels to go abroad, and counterparts returned together with the patients. A total of 233 overseas imported malaria cases were reported, and 226 cases (97.0%) were imported from African countries. A total of 208 cases (89.3%) were falciparum malaria, and 224 cases (96.1%) were laboratory-confirmed. The imported malaria cases were young adults who were mainly migrant farmer and skilled male workers. There was no significant seasonal variation for onset time. Totally 145 cases (62.2%) got malaria onset in 20 days after returning home. The median time from onset to seeing doctor was two days and the median time from seeing doctor to being diagnosed was one day. The first visit health facilities by the patients were relatively scattered and the diagnostic health facilities were mainly medical institutions and CDC at the county level and above (220 cases, accounting for 94.4%). The ratio of standard treatment after malaria diagnosis was 100%. A total of 205 cases (88.0%) were workers dispatched to abroad as labor export by the company, and 142 cases (60.9%) cases had counterparts returned together. The situation of overseas imported malaria in Jiangsu Province is severe. It is necessary to further strengthen the professional training and multi-sectoral cooperation, establish the collaborative investigation mechanism for high-risk groups, and take effective prevention and control measures
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NASA Technical Reports Server (NTRS)
Kiang, R.; Adimi, F.; Nigro, J.
2007-01-01
Meteorological and environmental parameters important to malaria transmission include temperature, relative humidity, precipitation, and vegetation conditions. These parameters can most conveniently be obtained using remote sensing. Selected provinces and districts in Thailand and Indonesia are used to illustrate how remotely sensed meteorological and environmental parameters may enhance the capabilities for malaria surveillance and control. Hindcastings based on these environmental parameters have shown good agreement to epidemiological records.
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[Current malaria situation in Turkey].
Gockchinar, T; Kalipsi, S
2001-01-01
Geographically, Turkey is situated in an area where malaria is very risky. The climatic conditions in the region are suitable for the malaria vector to proliferate. Due to agricultural infrastructural changes, GAP and other similar projects, insufficient environmental conditions, urbanization, national and international population moves, are a key to manage malaria control activities. It is estimated that malaria will be a potential danger for Turkey in the forthcoming years. The disease is located largely in south-eastern Anatolia. The Diyarbakir, Batman, Sanliurfa, Siirt, and Mardin districts are the most affected areas. In western districts, like Aydin and Manisa, an increase in the number of indigenous cases can be observed from time to time. This is due to workers moving from malaria districts to western parts to final work. Since these workers cannot be controlled, the population living in these regions get infected from indigenous cases. There were 84,345 malaria cases in 1994 and 82,096 in 1995, they decreased to 60,884 in 1996 and numbered 35,456 in 1997. They accounted for 36,842 and 20,963 in 1998 and 1999, respectively. In Turkey there are almost all cases of P. vivax malaria. There are also P. vivax and P. falciparum malaria cases coming from other countries: There were 321 P. vivax cases, including 2 P. falciparum ones, arriving to Turkey from Iraq in 1995. The P. vivax malaria cases accounted for 229 in 1996, and 67, cases P. vivax including 12 P. falciparum cases, in 1997, and 4 P. vivax cases in 1998 that came from that country. One P. vivax case entered Turkey from Georgia in 1998. The cause of higher incidence of P. vivax cases in 1995, it decreasing in 1999, is the lack of border controls over workers coming to Turkey. The other internationally imported cases are from Syria, Sudan, Pakistan, Afghanistan, Nigeria, India, Azerbaijan, Malaysia, Ghana, Indonesia, Yemen. Our examinations have shown that none of these internationally imported cases
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Hershey, Christine L.; Florey, Lia S.; Ali, Doreen; Bennett, Adam; Luhanga, Misheck; Mathanga, Don P.; Salgado, S. René; Nielsen, Carrie F.; Troell, Peter; Jenda, Gomezgani; Yé, Yazoume; Bhattarai, Achuyt
2017-01-01
Abstract. Malaria control intervention coverage increased nationwide in Malawi during 2000–2010. Trends in intervention coverage were assessed against trends in malaria parasite prevalence, severe anemia (hemoglobin < 8 g/dL), and all-cause mortality in children under 5 years of age (ACCM) using nationally representative household surveys. Associations between insecticide-treated net (ITN) ownership, malaria morbidity, and ACCM were also assessed. Household ITN ownership increased from 27.4% (95% confidence interval [CI] = 25.9–29.0) in 2004 to 56.8% (95% CI = 55.6–58.1) in 2010. Similarly intermittent preventive treatment during pregnancy coverage increased from 28.2% (95% CI = 26.7–29.8) in 2000 to 55.0% (95% CI = 53.4–56.6) in 2010. Malaria parasite prevalence decreased significantly from 60.5% (95% CI = 53.0–68.0) in 2001 to 20.4% (95% CI = 15.7–25.1) in 2009 in children aged 6–35 months. Severe anemia prevalence decreased from 20.4% (95% CI: 17.3–24.0) in 2004 to 13.1% (95% CI = 11.0–15.4) in 2010 in children aged 6–23 months. ACCM decreased 41%, from 188.6 deaths per 1,000 live births (95% CI = 179.1–198.0) during 1996–2000, to 112.1 deaths per 1,000 live births (95% CI = 105.8–118.5) during 2006–2010. When controlling for other covariates in random effects logistic regression models, household ITN ownership was protective against malaria parasitemia in children (odds ratio [OR] = 0.81, 95% CI = 0.72–0.92) and severe anemia (OR = 0.82, 95% CI = 0.72–0.94). After considering the magnitude of changes in malaria intervention coverage and nonmalaria factors, and given the contribution of malaria to all-cause mortality in malaria-endemic countries, the substantial increase in malaria control interventions likely improved child survival in Malawi during 2000–2010. PMID:28990920
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Application of spatial technology in malaria research & control: some new insights.
Saxena, Rekha; Nagpal, B N; Srivastava, Aruna; Gupta, S K; Dash, A P
2009-08-01
Geographical information System (GIS) has emerged as the core of the spatial technology which integrates wide range of dataset available from different sources including Remote Sensing (RS) and Global Positioning System (GPS). Literature published during the decade (1998-2007) has been compiled and grouped into six categories according to the usage of the technology in malaria epidemiology. Different GIS modules like spatial data sources, mapping and geo-processing tools, distance calculation, digital elevation model (DEM), buffer zone and geo-statistical analysis have been investigated in detail, illustrated with examples as per the derived results. These GIS tools have contributed immensely in understanding the epidemiological processes of malaria and examples drawn have shown that GIS is now widely used for research and decision making in malaria control. Statistical data analysis currently is the most consistent and established set of tools to analyze spatial datasets. The desired future development of GIS is in line with the utilization of geo-statistical tools which combined with high quality data has capability to provide new insight into malaria epidemiology and the complexity of its transmission potential in endemic areas.
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2012-01-01
Background Control of mosquitoes that transmit malaria has been the mainstay in the fight against the disease, but alternative methods are required in view of emerging insecticide resistance. Entomopathogenic fungi are candidate alternatives, but to date, few trials have translated the use of these agents to field-based evaluations of their actual impact on mosquito survival and malaria risk. Mineral oil-formulations of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were applied using five different techniques that each exploited the behaviour of malaria mosquitoes when entering, host-seeking or resting in experimental huts in a malaria endemic area of rural Tanzania. Results Survival of mosquitoes was reduced by 39-57% relative to controls after forcing upward house-entry of mosquitoes through fungus treated baffles attached to the eaves or after application of fungus-treated surfaces around an occupied bed net (bed net strip design). Moreover, 68 to 76% of the treatment mosquitoes showed fungal growth and thus had sufficient contact with fungus treated surfaces. A population dynamic model of malaria-mosquito interactions shows that these infection rates reduce malaria transmission by 75-80% due to the effect of fungal infection on adult mortality alone. The model also demonstrated that even if a high proportion of the mosquitoes exhibits outdoor biting behaviour, malaria transmission was still significantly reduced. Conclusions Entomopathogenic fungi strongly affect mosquito survival and have a high predicted impact on malaria transmission. These entomopathogens represent a viable alternative for malaria control, especially if they are used as part of an integrated vector management strategy. PMID:22449130
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KILLEEN, GERRY F.; McKENZIE, F. ELLIS; FOY, BRIAN D.; SCHIEFFELIN, CATHERINE; BILLINGSLEY, PETER F.; BEIER, JOHN C.
2008-01-01
We have used a relatively simple but accurate model for predicting the impact of integrated transmission control on the malaria entomologic inoculation rate (EIR) at four endemic sites from across sub-Saharan Africa and the southwest Pacific. The simulated campaign incorporated modestly effective vaccine coverage, bed net use, and larval control. The results indicate that such campaigns would reduce EIRs at all four sites by 30- to 50-fold. Even without the vaccine, 15- to 25-fold reductions of EIR were predicted, implying that integrated control with a few modestly effective tools can meaningfully reduce malaria transmission in a range of endemic settings. The model accurately predicts the effects of bed nets and indoor spraying and demonstrates that they are the most effective tools available for reducing EIR. However, the impact of domestic adult vector control is amplified by measures for reducing the rate of emergence of vectors or the level of infectiousness of the human reservoir. We conclude that available tools, including currently neglected methods for larval control, can reduce malaria transmission intensity enough to alleviate mortality. Integrated control programs should be implemented to the fullest extent possible, even in areas of intense transmission, using simple models as decision-making tools. However, we also conclude that to eliminate malaria in many areas of intense transmission is beyond the scope of methods which developing nations can currently afford. New, cost-effective, practical tools are needed if malaria is ever to be eliminated from highly endemic areas. PMID:11289662
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Evaluation of the Clearview® malaria pLDH malaria rapid diagnostic test in a non-endemic setting
2011-01-01
Background Malaria Rapid Diagnostic Tests (RDTs) are widely used to diagnose malaria. The present study evaluated a new RDT, the Clearview® Malaria pLDH test targeting the pan-Plasmodium antigen lactate dehydrogenase (pLDH). Methods The Clearview® Malaria pLDH test was evaluated on fresh samples obtained in returned international travellers using microscopy corrected by PCR as the reference method. Included samples were Plasmodium falciparum (139), Plasmodium vivax (22), Plasmodium ovale (20), Plasmodium malariae (7), and 102 negative. Results Overall sensitivity for the detection of Plasmodium spp was 93.2%. For P. falciparum, the sensitivity was 98.6%; for P. vivax, P. ovale and P. malariae, overall sensitivities were 90.9%, 60.0% and 85.7% respectively. For P. falciparum and for P. vivax, the sensitivities increased to 100% at parasite densities above 100/μl. The specificity was 100%. The test was easily to perform and the result was stable for at least 1 hour. Conclusion The Clearview® Malaria pLDH was efficient for the diagnosis of malaria. The test was very sensitive for P. falciparum and P. vivax detection. The sensitivities for P. ovale and P. malariae were better than other RDTs PMID:21951996
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Ouattara, Amed; Laurens, Matthew B
2015-03-15
Despite global efforts to control malaria, the illness remains a significant public health threat. Currently, there is no licensed vaccine against malaria, but an efficacious vaccine would represent an important public health tool for successful malaria elimination. Malaria vaccine development continues to be hindered by a poor understanding of antimalarial immunity, a lack of an immune correlate of protection, and the genetic diversity of malaria parasites. Current vaccine development efforts largely target Plasmodium falciparum parasites in the pre-erythrocytic and erythrocytic stages, with some research on transmission-blocking vaccines against asexual stages and vaccines against pregnancy-associated malaria. The leading pre-erythrocytic vaccine candidate is RTS,S, and early results of ongoing Phase 3 testing show overall efficacy of 46% against clinical malaria. The next steps for malaria vaccine development will focus on the design of a product that is efficacious against the highly diverse strains of malaria and the identification of a correlate of protection against disease. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
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Economic aspects of the use of impregnated mosquito nets for malaria control.
Brinkmann, U.; Brinkmann, A.
1995-01-01
The use of pyrethroids to impregnate mosquito nets has had a good impact on the incidence of morbidity and mortality from malaria. These nets are therefore likely to be used on a large scale as an important strategy of malaria control in the future. Published information on the cost and effectiveness of mosquito nets is presented and analysed. In two examples, from Malawi and Cameroon, the per household expenditure to purchase and use impregnated mosquito nets compares favourably with the costs of malaria. Thus, we expect that the economic losses from malaria would be reduced by 37.3% over a 3-year period in Malawi. Even if the impact of malaria on productivity is not taken into account, the introduction of nets will result in gains, as shown in Cameroon; savings of 9.3% and 11.2% in two places resulted as a consequence of a diminished need for case treatment. The role of government programmes in the promotion of bednets is indirect and concerned mainly with facilitation and the dissemination of information. Much depends on the capability of the private sector and the willingness of the target population to buy the nets for a programme to be effective. Specific studies by health economists on this subject are lacking. PMID:8846491
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Rapid identification of genes controlling virulence and immunity in malaria parasites
Xangsayarath, Phonepadith; Tang, Jianxia; Yahata, Kazuhide; Zoungrana, Augustin; Mitaka, Hayato; Acharjee, Arita; Datta, Partha P.; Hunt, Paul; Carter, Richard; Kaneko, Osamu; Mustonen, Ville; Pain, Arnab
2017-01-01
Identifying the genetic determinants of phenotypes that impact disease severity is of fundamental importance for the design of new interventions against malaria. Here we present a rapid genome-wide approach capable of identifying multiple genetic drivers of medically relevant phenotypes within malaria parasites via a single experiment at single gene or allele resolution. In a proof of principle study, we found that a previously undescribed single nucleotide polymorphism in the binding domain of the erythrocyte binding like protein (EBL) conferred a dramatic change in red blood cell invasion in mutant rodent malaria parasites Plasmodium yoelii. In the same experiment, we implicated merozoite surface protein 1 (MSP1) and other polymorphic proteins, as the major targets of strain-specific immunity. Using allelic replacement, we provide functional validation of the substitution in the EBL gene controlling the growth rate in the blood stages of the parasites. PMID:28704525
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The economic burden of malaria.
Gallup, J L; Sachs, J D
2001-01-01
Malaria and poverty are intimately connected. Controlling for factors such as tropical location, colonial history, and geographical isolation, countries with intensive malaria had income levels in 1995 of only 33% that of countries without malaria, whether or not the countries were in Africa. The high levels of malaria in poor countries are not mainly a consequence of poverty. Malaria is geographically specific. The ecological conditions that support the more efficient malaria mosquito vectors primarily determine the distribution and intensity of the disease. Intensive efforts to eliminate malaria in the most severely affected tropical countries have been largely ineffective. Countries that have eliminated malaria in the past half century have all been either subtropical or islands. These countries' economic growth in the 5 years after eliminating malaria has usually been substantially higher than growth in the neighboring countries. Cross-country regressions for the 1965-1990 period confirm the relationship between malaria and economic growth. Taking into account initial poverty, economic policy, tropical location, and life expectancy, among other factors, countries with intensive malaria grew 1.3% less per person per year, and a 10% reduction in malaria was associated with 0.3% higher growth. Controlling for many other tropical diseases does not change the correlation of malaria with economic growth, and these diseases are not themselves significantly negatively correlated with economic growth. A second independent measure of malaria has a slightly higher correlation with economic growth in the 1980-1996 period. We speculate about the mechanisms that could cause malaria to have such a large impact on the economy, such as foreign investment and economic networks within the country.
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Rodríguez, Américo David; Penilla, Rosa Patricia; Henry-Rodríguez, Mario; Hemingway, Janet; Francisco Betanzos, Angel; Hernández-Avila, Juan Eugenio
2003-01-01
To investigate the knowledge and beliefs about malaria transmission and practices for vector control in eight villages on the coastal plain of Chiapas, Mexico. A cross-sectional survey was conducted during May and June 1995 in Chiapas, Mexico. A questionnaire to investigate family structure, knowledge on malaria transmission, preventive measures and attitudes towards seeking treatment was applied to both family heads of a sample of households. Associations were analyzed by estimating odds ratios with confidence intervals and p values, using bivariate and multivariate logistic regression methods. Malaria knowledge was poor and only 48% associated malaria with mosquito bites. The perceived benefit of indoor residual spraying was associated to a reduction of mosquitoes, a reduction in the numbers of cockroaches and rats, but only 3% associated it directly with the prevention of malaria transmission. Most villagers (97.6%) agreed with the indoor residual spraying of insecticides. Ninety nine percent of villagers had mosquito bednets, 75.7% used them all year round. Other measures used by villagers to prevent mosquito bites were smoke and mosquito coils. Above 40% of villagers self-medicated when any member of the family had a fever episode, but 51% attended proper health services (community dispensary, private physician, health worker). About 61% used pesticides for agricultural or livestock purposes and 55% applied themselves. Women had a greater participation as family health promoters, with 70% of the housewives being in charge of the application of self-protection preventive measures. Educational programs aimed at increasing awareness on the participation of mosquitoes on malaria transmission could promote community participation in malaria control in the region. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.
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Plasmodium vivax hospitalizations in a monoendemic malaria region: severe vivax malaria?
Quispe, Antonio M; Pozo, Edwar; Guerrero, Edith; Durand, Salomón; Baldeviano, G Christian; Edgel, Kimberly A; Graf, Paul C F; Lescano, Andres G
2014-07-01
Severe malaria caused by Plasmodium vivax is no longer considered rare. To describe its clinical features, we performed a retrospective case control study in the subregion of Luciano Castillo Colonna, Piura, Peru, an area with nearly exclusive vivax malaria transmission. Severe cases and the subset of critically ill cases were compared with a random set of uncomplicated malaria cases (1:4). Between 2008 and 2009, 6,502 malaria cases were reported, including 106 hospitalized cases, 81 of which fit the World Health Organization definition for severe malaria. Of these 81 individuals, 28 individuals were critically ill (0.4%, 95% confidence interval = 0.2-0.6%) with severe anemia (57%), shock (25%), lung injury (21%), acute renal failure (14%), or cerebral malaria (11%). Two potentially malaria-related deaths occurred. Compared with uncomplicated cases, individuals critically ill were older (38 versus 26 years old, P < 0.001), but similar in other regards. Severe vivax malaria monoinfection with critical illness is more common than previously thought. © The American Society of Tropical Medicine and Hygiene.
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Analysing the quality of routine malaria data in Mozambique
Chilundo, Baltazar; Sundby, Johanne; Aanestad, Margunn
2004-01-01
Background In Mozambique, malaria is the principal cause of morbidity and mortality. Efforts are being made to increase control activities within communities. These activities require management decisions based on evidence of malaria incidence. Although some data generated are of poor quality, there is little research towards improving the reporting systems. Methods An analysis of the quality of routine malaria data was performed in selected districts in Southern Mozambique from August to September 2003. The aim was to assess the quality of the source data in terms of completeness, correctness and consistency across management levels. Results Analysis revealed primary data to be of poor quality. The diversity of reporting systems with limited coordination give rise to redundancies and wastage of resources. There was evidence of "invention" of data in health facilities contributing to an incorrect representation of malaria incidence. Large, "non-clinical", time-based variations of malaria cases due to reporting delays were also noted, contributing to false alerts of outbreaks. Furthermore, targets established in the national strategic plan for malaria cannot be calculated through the existing systems; this is the case, for example, for data related to pregnant women and children under-five years. Discussion and recommendations The existing reporting system for malaria is currently not satisfying the information needs of managers. It is suggested that one standardized system, including the creation of one form to include the essential variables required for the calculation of key indicators by age, gender and pregnancy status, and to establish a national database that maps malaria by location. PMID:14998435
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A Literature Review of the Effect of Malaria on Stunting.
Jackson, Bianca D; Black, Robert E
2017-11-01
Background: The current version of the Lives Saved Tool (LiST) maternal and child health impact modeling software does not include an effect of malaria on stunting. Objective: This literature review was undertaken to determine whether such a causal link should be included in the LiST model. Methods: The PubMed, Embase, and Scopus databases were searched by using broad search terms. The searches returned a total of 4281 documents. Twelve studies from among the retrieved documents were included in the review according to the inclusion and exclusion criteria. Results: There was mixed evidence for an effect of malaria on stunting among longitudinal observational studies, and none of the randomized controlled trials of malaria interventions found an effect of the interventions on stunting. Conclusions: There is insufficient evidence to include malaria as a determinant of stunting or an effect of malaria interventions on stunting in the LiST model. The paucity and heterogeneity of the available literature were a major limitation. In addition, the studies included in the review consistently fulfilled their ethical responsibility to treat children under observation for malaria, which may have interfered with the natural history of the disease and prevented any observable effect on stunting or linear growth. © 2017 American Society for Nutrition.
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2014-01-01
Background Countries in the Asia Pacific region have made great progress in the fight against malaria; several are rapidly approaching elimination. However, malaria control programmes operating in elimination settings face substantial challenges, particularly around mobile migrant populations, access to remote areas and the diversity of vectors with varying biting and breeding behaviours. These challenges can be addressed through subnational collaborations with commercial partners, such as mining or plantation companies, that can conduct or support malaria control activities to cover employees. Such partnerships can be a useful tool for accessing high-risk populations and supporting malaria elimination goals. Methods This observational qualitative case study employed semi-structured key informant interviews to describe partnerships between the Malaysian Malaria Control Programme (MCP), and private palm oil, rubber and acacia plantations in the state of Sabah. Semi-structured interview guides were used to examine resource commitments, incentives, challenges, and successes of the collaborations. Results Interviews with workers from private plantations and the state of Sabah MCP indicated that partnerships with the commercial sector had contributed to decreases in incidence at plantation sites since 1991. Several plantations contribute financial and human resources toward malaria control efforts and all plantations frequently communicate with the MCP to help monitor the malaria situation on-site. Management of partnerships between private corporations and government entities can be challenging, as prioritization of malaria control may change with annual profits or arrival of new management. Conclusions Partnering with the commercial sector has been an essential operational strategy to support malaria elimination in Sabah. The successes of these partnerships rely on a common understanding that elimination will be a mutually beneficial outcome for employers and the
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Plasmodium vivax Malaria in Cambodia
Siv, Sovannaroth; Roca-Feltrer, Arantxa; Vinjamuri, Seshu Babu; Bouth, Denis Mey; Lek, Dysoley; Rashid, Mohammad Abdur; By, Ngau Peng; Popovici, Jean; Huy, Rekol; Menard, Didier
2016-01-01
The Cambodian National Strategic Plan for Elimination of Malaria aims to move step by step toward elimination of malaria across Cambodia with an initial focus on Plasmodium falciparum malaria before achieving elimination of all forms of malaria, including Plasmodium vivax in 2025. The emergence of artemisinin-resistant P. falciparum in western Cambodia over the last decade has drawn global attention to support the ultimate goal of P. falciparum elimination, whereas the control of P. vivax lags much behind, making the 2025 target gradually less achievable unless greater attention is given to P. vivax elimination in the country. The following review presents in detail the past and current situation regarding P. vivax malaria, activities of the National Malaria Control Program, and interventional measures applied. Constraints and obstacles that can jeopardize our efforts to eliminate this parasite species are discussed. PMID:27708187
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Cohen, Justin M; Dlamini, Sabelo; Novotny, Joseph M; Kandula, Deepika; Kunene, Simon; Tatem, Andrew J
2013-02-11
As successful malaria control programmes move towards elimination, they must identify residual transmission foci, target vector control to high-risk areas, focus on both asymptomatic and symptomatic infections, and manage importation risk. High spatial and temporal resolution maps of malaria risk can support all of these activities, but commonly available malaria maps are based on parasite rate, a poor metric for measuring malaria at extremely low prevalence. New approaches are required to provide case-based risk maps to countries seeking to identify remaining hotspots of transmission while managing the risk of transmission from imported cases. Household locations and travel histories of confirmed malaria patients during 2011 were recorded through routine surveillance by the Swaziland National Malaria Control Programme for the higher transmission months of January to April and the lower transmission months of May to December. Household locations for patients with no travel history to endemic areas were compared against a random set of background points sampled proportionate to population density with respect to a set of variables related to environment, population density, vector control, and distance to the locations of identified imported cases. Comparisons were made separately for the high and low transmission seasons. The Random Forests regression tree classification approach was used to generate maps predicting the probability of a locally acquired case at 100 m resolution across Swaziland for each season. Results indicated that case households during the high transmission season tended to be located in areas of lower elevation, closer to bodies of water, in more sparsely populated areas, with lower rainfall and warmer temperatures, and closer to imported cases than random background points (all p < 0.001). Similar differences were evident during the low transmission season. Maps from the fit models suggested better predictive ability during the high
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Keiser, J; Utzinger, J; Premji, Z; Yamagata, Y; Singer, B H
2002-10-01
One hundred years ago, Giemsa's stain was employed for the first time for malaria diagnosis. Giemsa staining continues to be the method of choice in most malarious countries, although, in the recent past, several alternatives have been developed that exhibit some advantages. Considerable progress has been made with fluorescent dyes, particularly with Acridine Orange (AO). The literature on the discovery, development and validation of the AO method for malaria diagnosis is reviewed here. Compared with conventional Giemsa staining, AO shows a good diagnostic performance, with sensitivities of 81.3%-100% and specificities of 86.4%-100%. However, sensitivities decrease with lower parasite densities, and species differentiation may occasionally be difficult. The most notable advantage of the AO method over Giemsa staining is its promptness; results are readily available within 3-10 min, whereas Giemsa staining may take 45 min or even longer. This is an important advantage for the organization of health services and the provision of effective treatment of malaria cases. The national malaria control programme of Tanzania, together with the Japan International Co-operation Agency, began to introduce the AO method in Tanzania in 1994. So far, AO staining has been introduced in 70 regional and district hospitals, and 400 laboratory technicians have been trained to use the method. The results of this introduction, which are reviewed here and have several important implications, indicate that AO is a viable alternative technique for the laboratory diagnosis of malaria in highly endemic countries.
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SHAHI, Mehran; KAMRANI, Ehsan; SALEHI, Mehrdad; HABIBI, Reza; HANAFI-BOJD, Ahmad Ali
2015-01-01
Background: The widespread use of chemical insecticides, resistance in vectors and environmental problems, all have led to an increased interest in the use of biological agents in malaria control programs. The most important functional elements are the native fish. The aim of this study was to identify the native species of lavivorous fish in Rudan County, southern Iran, to introduce an effective species and to propose its’ implementation in the national malaria control program. Methods: This ecologically descriptive study was conducted during 2011–2012 using random sampling from different fish habitats of Rudan County. The shoals of fish were caught using fishing net. Fish samples were then identified in the Ichthyology lab, Department of Fisheries and the Environment, Hormozgan University. Results: Three species of larvivorous fish were identified as follows: Gambusia holbrooki, Aphaniusdispar dispar and Aphanius sp. The latter species has the most distribution in the study area and needs more morphological and molecular studies for identification at the species level. Conclusion: Two species of native fish, i.e., A. dispar and A. sp. with larvivorous potential live in the area. Further studies on their predatory property are recommended in order to apply this local potential against malaria vectors in the area. PMID:26744713
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Oguttu, David W; Matovu, Joseph K B; Okumu, David C; Ario, Alex R; Okullo, Allen E; Opigo, Jimmy; Nankabirwa, Victoria
2017-05-30
In 2012, Tororo District had the highest malaria burden in Uganda with community Plasmodium prevalence of 48%. To control malaria in the district, the Ministry of Health introduced universal distribution of long lasting insecticide-treated nets (LLINs) in 2013 and added indoor residual spraying (IRS) in 2014. This study assessed malaria incidence, test positivity rates and outpatient (OPD) attendance due to malaria before and after vector control interventions. This study was based on analysis of Health Management Information System (HMIS) secondary malaria surveillance data of 2,727,850 patient records in OPD registers of 61 health facilities from 2012 to 2015. The analysis estimated monthly malaria incidence for the entire population and also separately for <5- and ≥5-year-olds before and after introduction of vector control interventions; determined laboratory test positivity rates and annual percentage of malaria cases in OPD. Chi square for trends was used to analyse annual change in malaria incidence and logistic regression for monthly reduction. Following universal LLINs coverage, the annual mean monthly malaria incidence fell from 95 cases in 2013 to 76 cases per 1000 in 2014 with no significant monthly reduction (OR = 0.99, 95% CI 0.96-1.01, P = 0.37). Among children <5 years, the malaria incidence reduced from 130 to 100 cases per 1000 (OR = 0.98, 95% CI 0.97-1.00, P = 0.08) when LLINs were used alone in 2014, but declined to 45 per 1000 in 2015 when IRS was combined with LLINs (OR = 0.94, 95% CI 0.91-0.996, P < 0.0001). Among individuals aged ≥5 years, mean monthly malaria incidence reduced from 59 to 52 cases per 1000 (OR = 0.99, 95% CI 0.97-1.02, P = 0.8) when LLINs were used alone in 2014, but reduced significantly to 25 per 1000 in 2015 (OR = 0.91, 95% CI 0.88-0.94, P < 0.0001). Malaria test positivity rate reduced from 57% in 2013 to 30% (Chi = 15, P < 0.0001) in 2015. Slide positivity rate reduced from 45% in 2013
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Escalante, Ananias A.; Ferreira, Marcelo U.; Vinetz, Joseph M.; Volkman, Sarah K.; Cui, Liwang; Gamboa, Dionicia; Krogstad, Donald J.; Barry, Alyssa E.; Carlton, Jane M.; van Eijk, Anna Maria; Pradhan, Khageswar; Mueller, Ivo; Greenhouse, Bryan; Andreina Pacheco, M.; Vallejo, Andres F.; Herrera, Socrates; Felger, Ingrid
2015-01-01
Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts. PMID:26259945
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Challenges for malaria elimination in Brazil.
Ferreira, Marcelo U; Castro, Marcia C
2016-05-20
Brazil currently contributes 42 % of all malaria cases reported in the Latin America and the Caribbean, a region where major progress towards malaria elimination has been achieved in recent years. In 2014, malaria burden in Brazil (143,910 microscopically confirmed cases and 41 malaria-related deaths) has reached its lowest levels in 35 years, Plasmodium falciparum is highly focal, and the geographic boundary of transmission has considerably shrunk. Transmission in Brazil remains entrenched in the Amazon Basin, which accounts for 99.5 % of the country's malaria burden. This paper reviews major lessons learned from past and current malaria control policies in Brazil. A comprehensive discussion of the scientific and logistic challenges that may impact malaria elimination efforts in the country is presented in light of the launching of the Plan for Elimination of Malaria in Brazil in November 2015. Challenges for malaria elimination addressed include the high prevalence of symptomless and submicroscopic infections, emerging anti-malarial drug resistance in P. falciparum and Plasmodium vivax and the lack of safe anti-relapse drugs, the largely neglected burden of malaria in pregnancy, the need for better vector control strategies where Anopheles mosquitoes present a highly variable biting behaviour, human movement, the need for effective surveillance and tools to identify foci of infection in areas with low transmission, and the effects of environmental changes and climatic variability in transmission. Control actions launched in Brazil and results to come are likely to influence control programs in other countries in the Americas.
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Beer Consumption Increases Human Attractiveness to Malaria Mosquitoes
Lefèvre, Thierry; Gouagna, Louis-Clément; Dabiré, Kounbobr Roch; Elguero, Eric; Fontenille, Didier; Renaud, François; Costantini, Carlo; Thomas, Frédéric
2010-01-01
Background Malaria and alcohol consumption both represent major public health problems. Alcohol consumption is rising in developing countries and, as efforts to manage malaria are expanded, understanding the links between malaria and alcohol consumption becomes crucial. Our aim was to ascertain the effect of beer consumption on human attractiveness to malaria mosquitoes in semi field conditions in Burkina Faso. Methodology/Principal Findings We used a Y tube-olfactometer designed to take advantage of the whole body odour (breath and skin emanations) as a stimulus to gauge human attractiveness to Anopheles gambiae (the primary African malaria vector) before and after volunteers consumed either beer (n = 25 volunteers and a total of 2500 mosquitoes tested) or water (n = 18 volunteers and a total of 1800 mosquitoes). Water consumption had no effect on human attractiveness to An. gambiae mosquitoes, but beer consumption increased volunteer attractiveness. Body odours of volunteers who consumed beer increased mosquito activation (proportion of mosquitoes engaging in take-off and up-wind flight) and orientation (proportion of mosquitoes flying towards volunteers' odours). The level of exhaled carbon dioxide and body temperature had no effect on human attractiveness to mosquitoes. Despite individual volunteer variation, beer consumption consistently increased attractiveness to mosquitoes. Conclusions/Significance These results suggest that beer consumption is a risk factor for malaria and needs to be integrated into public health policies for the design of control measures. PMID:20209056
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Early malaria resurgence in pre-elimination areas in Kokap Subdistrict, Kulon Progo, Indonesia
2014-01-01
Background Indonesia is among those countries committed to malaria eradication, with a continuously decreasing incidence of malaria. However, at district level the situation is different. This study presents a case of malaria resurgence Kokap Subdistrict of the Kulon Progo District in Yogyakarta Province, Java after five years of low endemicity. This study also aims to describe the community perceptions and health services delivery situation that contribute to this case. Methods All malaria cases (2007–2011) in Kulon Progo District were stratified to annual parasite incidence (API). Two-hundred and twenty-six cases during an outbreak (May 2011 to April 2012) were geocoded by household addresses using a geographic information system (GIS) technique and clusters were identified by SaTScan software analysis (Arc GIS 10.1). Purposive random sampling was conducted on respondents living inside the clusters to identify community perceptions and behaviour related to malaria. Interviews were conducted with malaria health officers to understand the challenges of malaria surveillance and control. Results After experiencing three consecutive years with API less than 1 per thousand, malaria in Kokap subdistrict increased almost ten times higher than API in the district level and five times higher than national API. Malaria cases were found in all five villages in 2012. One primary and two secondary malaria clusters in Hargotirto and Kalirejo villages were identified during the 2011–2012 outbreak. Most of the respondents were positively aware with malaria signs and activities of health workers to prevent malaria, although some social economic activities could not be hindered. Return transmigrants or migrant workers entering to their villages, reduced numbers of village malaria workers and a surge in malaria cases in the neighbouring district contributed to the resurgence. Conclusion Community perception, awareness and participation could constitute a solid foundation for
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Blanford, Simon; Shi, Wangpeng; Christian, Riann; Marden, James H.; Koekemoer, Lizette L.; Brooke, Basil D.; Coetzee, Maureen; Read, Andrew F.; Thomas, Matthew B.
2011-01-01
Rapidly emerging insecticide resistance is creating an urgent need for new active ingredients to control the adult mosquitoes that vector malaria. Biopesticides based on the spores of entomopathogenic fungi have shown considerable promise by causing very substantial mortality within 7–14 days of exposure. This mortality will generate excellent malaria control if there is a high likelihood that mosquitoes contact fungi early in their adult lives. However, where contact rates are lower, as might result from poor pesticide coverage, some mosquitoes will contact fungi one or more feeding cycles after they acquire malaria, and so risk transmitting malaria before the fungus kills them. Critics have argued that ‘slow acting’ fungal biopesticides are, therefore, incapable of delivering malaria control in real-world contexts. Here, utilizing standard WHO laboratory protocols, we demonstrate effective action of a biopesticide much faster than previously reported. Specifically, we show that transient exposure to clay tiles sprayed with a candidate biopesticide comprising spores of a natural isolate of Beauveria bassiana, could reduce malaria transmission potential to zero within a feeding cycle. The effect resulted from a combination of high mortality and rapid fungal-induced reduction in feeding and flight capacity. Additionally, multiple insecticide-resistant lines from three key African malaria vector species were completely susceptible to fungus. Thus, fungal biopesticides can block transmission on a par with chemical insecticides, and can achieve this where chemical insecticides have little impact. These results support broadening the current vector control paradigm beyond fast-acting chemical toxins. PMID:21897846
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Adult vector control, mosquito ecology and malaria transmission
Brady, Oliver J.; Godfray, H. Charles J.; Tatem, Andrew J.; Gething, Peter W.; Cohen, Justin M.; McKenzie, F. Ellis; Alex Perkins, T.; Reiner, Robert C.; Tusting, Lucy S.; Scott, Thomas W.; Lindsay, Steven W.; Hay, Simon I.; Smith, David L.
2015-01-01
Background Standard advice regarding vector control is to prefer interventions that reduce the lifespan of adult mosquitoes. The basis for this advice is a decades-old sensitivity analysis of ‘vectorial capacity’, a concept relevant for most malaria transmission models and based solely on adult mosquito population dynamics. Recent advances in micro-simulation models offer an opportunity to expand the theory of vectorial capacity to include both adult and juvenile mosquito stages in the model. Methods In this study we revisit arguments about transmission and its sensitivity to mosquito bionomic parameters using an elasticity analysis of developed formulations of vectorial capacity. Results We show that reducing adult survival has effects on both adult and juvenile population size, which are significant for transmission and not accounted for in traditional formulations of vectorial capacity. The elasticity of these effects is dependent on various mosquito population parameters, which we explore. Overall, control is most sensitive to methods that affect adult mosquito mortality rates, followed by blood feeding frequency, human blood feeding habit, and lastly, to adult mosquito population density. Conclusions These results emphasise more strongly than ever the sensitivity of transmission to adult mosquito mortality, but also suggest the high potential of combinations of interventions including larval source management. This must be done with caution, however, as policy requires a more careful consideration of costs, operational difficulties and policy goals in relation to baseline transmission. PMID:25733562
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Tong, Michael Xiaoliang; Hansen, Alana; Hanson-Easey, Scott; Cameron, Scott; Xiang, Jianjun; Liu, Qiyong; Liu, Xiaobo; Sun, Yehuan; Weinstein, Philip; Han, Gil-Soo; Williams, Craig; Bi, Peng
2017-03-31
Though there was the significant decrease in the incidence of malaria in central and southwest China during the 1980s and 1990s, there has been a re-emergence of malaria since 2000. A cross-sectional survey was conducted amongst the staff of eleven Centers for Disease Control and Prevention (CDC) in China to gauge their perceptions regarding the impacts of climate change on malaria transmission and its control and prevention. Descriptive analysis was performed to study CDC staff's knowledge, attitudes, perceptions and suggestions for malaria control in the face of climate change. A majority (79.8%) of CDC staff were concerned about climate change and 79.7% believed the weather was becoming warmer. Most participants (90.3%) indicated climate change had a negative effect on population health, 92.6 and 86.8% considered that increasing temperatures and precipitation would influence the transmission of vector-borne diseases including malaria. About half (50.9%) of the surveyed staff indicated malaria had re-emerged in recent years, and some outbreaks were occurring in new geographic areas. The main reasons for such re-emergence were perceived to be: mosquitoes in high-density, numerous imported cases, climate change, poor environmental conditions, internal migrant populations, and lack of health awareness. This study found most CDC staff endorsed the statement that climate change had a negative impact on infectious disease transmission. Malaria had re-emerged in some areas of China, and most of the staff believed that this can be managed. However, high densities of mosquitoes and the continuous increase in imported cases of malaria in local areas, together with environmental changes are bringing about critical challenges to malaria control in China. This study contributes to an understanding of climate change related perceptions of malaria control and prevention amongst CDC staff. It may help to formulate in-house training guidelines, community health promotion
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A public-private partnership for malaria control: lessons from the Malarone Donation Programme.
Oyediran, A. B. O. Olukayode; Ddumba, Edward M.; Ochola, Samuel A.; Lucas, Adetokunbo O.; Koporc, Kim; Dowdle, Walter R.
2002-01-01
In 1996, Glaxo Wellcome offered to donate up to a million treatment courses annually of Malarone, a new antimalarial, with a view to reducing the global burden of malaria. The Malarone Donation Programme (MDP) was established the following year. Eight pilot sites were selected in Kenya and Uganda to develop and evaluate an effective, locally sustainable donation strategy that ensured controlled and appropriate use of Malarone. The pilot programme targeted individuals who had acute uncomplicated Plasmodium falciparum malaria that had not responded to first-line treatments with chloroquine or sulfadoxine-pyrimethamine. Of the 161 079 patients clinically diagnosed at the pilot sites as having malaria, 1101 (0.68%) met all the conditions for participation and received directly observed treatment with Malarone. MDP had a positive effect at the pilot sites by improving the diagnosis and management of malaria. However, the provision of Malarone as a second-line drug at the district hospital level was not an efficient and effective use of resources. The number of deaths among children and adults ineligible for MDP at the pilot sites suggested that high priority should be given to meeting the challenges of malaria treatment at the community level. PMID:12471403
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Malaria vector control at a crossroads: public health entomology and the drive to elimination.
Mnzava, Abraham P; Macdonald, Michael B; Knox, Tessa B; Temu, Emmanuel A; Shiff, Clive J
2014-09-01
Vector control has been at the core of successful malaria control. However, a dearth of field-oriented vector biologists threatens to undermine global reductions in malaria burden. Skilled cadres are needed to manage insecticide resistance, to maintain coverage with current interventions, to develop new paradigms for tackling 'residual' transmission and to target interventions as transmission becomes increasingly heterogeneous. Recognising this human resource crisis, in September 2013, WHO Global Malaria Programme issued guidance for capacity building in entomology and vector control, including recommendations for countries and implementing partners. Ministries were urged to develop long-range strategic plans for building human resources for public health entomology and vector control (including skills in epidemiology, geographic information systems, operational research and programme management) and to set in place the requisite professional posts and career opportunities. Capacity building and national ownership in all partner projects and a clear exit strategy to sustain human and technical resources after project completion were emphasised. Implementing partners were urged to support global and regional efforts to enhance public health entomology capacity. While the challenges inherent in such capacity building are great, so too are the opportunities to establish the next generation of public health entomologists that will enable programmes to continue on the path to malaria elimination. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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2012-01-01
Background Malaria remains a serious epidemic threat in Mpumalanga Province. In order to appropriately target interventions to achieve substantial reduction in the burden of malaria and ultimately eliminate the disease, there is a need to track progress of malaria control efforts by assessing the time trends and evaluating the impact of current control interventions. This study aimed to assess the changes in the burden of malaria in Mpumalanga Province during the past eight malaria seasons (2001/02 to 2008/09) and whether indoor residual spraying (IRS) and climate variability had an effect on these changes. Methods This is a descriptive retrospective study based on the analysis of secondary malaria surveillance data (cases and deaths) in Mpumalanga Province. Data were extracted from the Integrated Malaria Information System. Time series model (Autoregressive Integrated Moving Average) was used to assess the association between climate and malaria. Results Within the study period, a total of 35,191 cases and 164 deaths due to malaria were notified in Mpumalanga Province. There was a significant decrease in the incidence of malaria from 385 in 2001/02 to 50 cases per 100,000 population in 2008/09 (P < 0.005). The incidence and case fatality (CFR) rates for the study period were 134 cases per 100,000 and 0.54%, respectively. Mortality due to malaria was lower in infants and children (CFR < 0.5%) and higher in those >65 years, with the mean CFR of 2.1% as compared to the national target of 0.5%. A distinct seasonal transmission pattern was found to be significantly related to changes in rainfall patterns (P = 0.007). A notable decline in malaria case notification was observed following apparent scale-up of IRS coverage from 2006/07 to 2008/09 malaria seasons. Conclusions Mpumalanga Province has achieved the goal of reducing malaria morbidity and mortality by over 70%, partly as a result of scale-up of IRS intervention in combination with other control strategies. These
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Review of research on malaria*
Lepes, T.
1974-01-01
This review of progress in malaria research over the periods 1951-1970 and 1970-1973 indicates the results so far achieved in research on the parasite, on the immune response of the host, and on the vector; refers to the means of controlling or eradicating malaria that have been developed in recent years; and outlines the present status of the malaria control and eradication programme. Although impressive results have already been achieved in malaria research, more systematization and concentration of efforts are required if real breakthroughs are to be made. The experience gained in this respect is discussed. PMID:4613499
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Walker, K; Lynch, M
2007-03-01
Malaria vector control targeting the larval stages of mosquitoes was applied successfully against many species of Anopheles (Diptera: Culicidae) in malarious countries until the mid-20th Century. Since the introduction of DDT in the 1940s and the associated development of indoor residual spraying (IRS), which usually has a more powerful impact than larval control on vectorial capacity, the focus of malaria prevention programmes has shifted to the control of adult vectors. In the Afrotropical Region, where malaria is transmitted mainly by Anopheles funestus Giles and members of the Anopheles gambiae Giles complex, gaps in information on larval ecology and the ability of An. gambiae sensu lato to exploit a wide variety of larval habitats have discouraged efforts to develop and implement larval control strategies. Opportunities to complement adulticiding with other components of integrated vector management, along with concerns about insecticide resistance, environmental impacts, rising costs of IRS and logistical constraints, have stimulated renewed interest in larval control of malaria vectors. Techniques include environmental management, involving the temporary or permanent removal of anopheline larval habitats, as well as larviciding with chemical or biological agents. This present review covers large-scale trials of anopheline larval control methods, focusing on field studies in Africa conducted within the past 15 years. Although such studies are limited in number and scope, their results suggest that targeting larvae, particularly in human-made habitats, can significantly reduce malaria transmission in appropriate settings. These approaches are especially suitable for urban areas, where larval habitats are limited, particularly when applied in conjunction with IRS and other adulticidal measures, such as the use of insecticide treated bednets.
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Is There a Risk of Suburban Transmission of Malaria in Selangor, Malaysia?
Braima, Kamil A.; Sum, Jia-Siang; Ghazali, Amir-Ridhwan M.; Muslimin, Mustakiza; Jeffery, John; Lee, Wenn-Chyau; Shaker, Mohammed R.; Elamin, Alaa-Eldeen M.; Jamaiah, Ibrahim; Lau, Yee-Ling; Rohela, Mahmud; Kamarulzaman, Adeeba; Sitam, Frankie; Mohd-Noh, Rosnida; Abdul-Aziz, Noraishah M.
2013-01-01
Background The suburban transmission of malaria in Selangor, Malaysia’s most developed and populous state still remains a concern for public health in this region. Despite much successful control efforts directed at its reduction, sporadic cases, mostly brought in by foreigners have continued to occur. In addition, cases of simian malaria caused by Plasmodium knowlesi, some with fatal outcome have caused grave concern to health workers. The aim of this study was to investigate the possibility of local malaria transmission in suburban regions of Selangor, which are adjacent to secondary rainforests. Findings A malaria survey spanning 7 years (2006 - 2012) was conducted in Selangor. A total of 1623 laboratory confirmed malaria cases were reported from Selangor’s nine districts. While 72.6% of these cases (1178/1623) were attributed to imported malaria (cases originating from other countries), 25.5% (414/1623) were local cases and 1.9% (31/1623) were considered as relapse and unclassified cases combined. In this study, the most prevalent infection was P. vivax (1239 cases, prevalence 76.3%) followed by P. falciparum (211, 13.0%), P. knowlesi (75, 4.6%), P. malariae (71, 4.4%) and P. ovale (1, 0.06%). Mixed infections comprising of P. vivax and P. falciparum were confirmed (26, 1.6%). Entomological surveys targeting the residences of malaria patients’ showed that the most commonly trapped Anopheles species was An. maculatus. No oocysts or sporozoites were found in the An. maculatus collected. Nevertheless, the possibility of An. maculatus being the malaria vector in the investigated locations was high due to its persistent occurrence in these areas. Conclusions Malaria cases reported in this study were mostly imported cases. However the co-existence of local cases and potential Plasmodium spp. vectors should be cause for concern. The results of this survey reflect the need of maintaining closely monitored malaria control programs and continuous extensive malaria
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Chen-Hussey, Vanessa; Carneiro, Ilona; Keomanila, Hongkham; Gray, Rob; Bannavong, Sihamano; Phanalasy, Saysana; Lindsay, Steven W.
2013-01-01
Background Mosquito vectors of malaria in Southeast Asia readily feed outdoors making malaria control through indoor insecticides such as long-lasting insecticidal nets (LLINs) and indoor residual spraying more difficult. Topical insect repellents may be able to protect users from outdoor biting, thereby providing additional protection above the current best practice of LLINs. Methods and Findings A double blind, household randomised, placebo-controlled trial of insect repellent to reduce malaria was carried out in southern Lao PDR to determine whether the use of repellent and long-lasting insecticidal nets (LLINs) could reduce malaria more than LLINs alone. A total of 1,597 households, including 7,979 participants, were recruited in June 2009 and April 2010. Equal group allocation, stratified by village, was used to randomise 795 households to a 15% DEET lotion and the remainder were given a placebo lotion. Participants, field staff and data analysts were blinded to the group assignment until data analysis had been completed. All households received new LLINs. Participants were asked to apply their lotion to exposed skin every evening and sleep under the LLINs each night. Plasmodium falciparum and P. vivax cases were actively identified by monthly rapid diagnostic tests. Intention to treat analysis found no effect from the use of repellent on malaria incidence (hazard ratio: 1.00, 95% CI: 0.99–1.01, p = 0.868). A higher socio-economic score was found to significantly decrease malaria risk (hazard ratio: 0.72, 95% CI: 0.58–0.90, p = 0.004). Women were also found to have a reduced risk of infection (hazard ratio: 0.59, 95% CI: 0.37–0.92, p = 0.020). According to protocol analysis which excluded participants using the lotions less than 90% of the time found similar results with no effect from the use of repellent. Conclusions This randomised controlled trial suggests that topical repellents are not a suitable intervention in addition to LLINs
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Talisuna, Ambrose O; Noor, Abdisalan M; Okui, Albert P; Snow, Robert W
2015-04-15
An important prelude to developing strategies to control infectious diseases is a detailed epidemiological evidence platform to target cost-effective interventions and define resource needs. A review of published and un-published reports of malaria vector control and parasite prevention in Uganda was conducted for the period 1900-2013. The objective was to provide a perspective as to how epidemiological intelligence was used to design malaria control before and during the global malaria eradication programme (GMEP) and to contrast this with the evidence generated in support of the Roll Back Malaria (RBM) initiative from 1998 to date. During the GMEP era, comprehensive investigations were undertaken on the effectiveness of vector and parasite control such as indoor residual house-spraying (IRS) and mass drug administration (MDA) at different sites in Uganda. Nationwide malariometric surveys were undertaken between 1964 and 1967 to provide a profile of risk, epidemiology and seasonality leading to an evidence-based national cartography of risk to characterize the diversity of malaria transmission in Uganda. At the launch of the RBM initiative in the late 1990s, an equivalent level of evidence was lacking. There was no contemporary national evidence-base for the likely impact of insecticide-treated nets (ITN), no new malariometric data, no new national cartography of malaria risk or any evidence of tailored intervention delivery based on variations in the ecology of malaria risk in Uganda. Despite millions of dollars of overseas development assistance over the last ten years in ITN, and more recently the resurrection of the use of IRS, the epidemiological impact of vector control remains uncertain due to an absence of nationwide basic parasite and vector-based field studies. Readily available epidemiological data should become the future business model to maximize malaria funding from 2015. Over the next five to ten years, accountability, impact analysis, financial
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The Gates Malaria Partnership: a consortium approach to malaria research and capacity development.
Greenwood, Brian; Bhasin, Amit; Targett, Geoffrey
2012-05-01
Recently, there has been a major increase in financial support for malaria control. Most of these funds have, appropriately, been spent on the tools needed for effective prevention and treatment of malaria such as insecticide-treated bed nets, indoor residual spraying and artemisinin combination therapy. There has been less investment in the training of the scientists from malaria-endemic countries needed to support these large and increasingly complex malaria control programmes, especially in Africa. In 2000, with support from the Bill & Melinda Gates Foundation, the Gates Malaria Partnership was established to support postgraduate training of African scientists wishing to pursue a career in malaria research. The programme had three research capacity development components: a PhD fellowship programme, a postdoctoral fellowship programme and a laboratory infrastructure programme. During an 8-year period, 36 African PhD students and six postdoctoral fellows were supported, and two research laboratories were built in Tanzania. Some of the lessons learnt during this project--such as the need to improve PhD supervision in African universities and to provide better support for postdoctoral fellows--are now being applied to a successor malaria research capacity development programme, the Malaria Capacity Development Consortium, and may be of interest to other groups involved in improving postgraduate training in health sciences in African universities. © 2012 Blackwell Publishing Ltd.
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The role of vector control in stopping the transmission of malaria: threats and opportunities.
Hemingway, Janet
2014-01-01
Malaria control, and that of other insect borne diseases such as dengue, is heavily dependent on our ability to control the mosquito populations that transmit these diseases. The major push over the last decade to reduce the global burden of malaria has been driven by the distribution of pyrethroid insecticide-treated bednets and an increase in coverage of indoor residual spraying (IRS). This has reduced malaria deaths by a third. Progress towards the goal of reducing this further is threatened by lack of funding and the selection of drug and insecticide resistance. When malaria control was initially scaled up, there was little pyrethroid resistance in the major vectors, today there is no country in Africa where the vectors remain fully susceptible to pyrethroids. The first pyrethroid resistance mechanisms to be selected produced low-level resistance which had little or no operational significance. More recently, metabolically based resistance has been selected, primarily in West Africa, which in some mosquito populations produces more than 1000-fold resistance. As this spreads the effectiveness of pyrethroid-based bednets and IRS will be compromised. New public health insecticides are not readily available. The pipeline of agrochemical insecticides that can be re-purposed for public health dried up 30 years ago when the target product profile for agricultural insecticides shifted from broad spectrum, stable, contact-acting insecticides to narrow spectrum stomach poisons that could be delivered through the plant. A public-private partnership, the Innovative Vector Control Consortium, was established in 2005 to stimulate the development of new public health pesticides. Nine potential new classes of chemistry are in the pipeline, with the intention of developing three into new insecticides. While this has been successfully achieved, it will still take 6-9 years for new insecticides to reach the market. Careful management of the resistance situation in the interim
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The role of vector control in stopping the transmission of malaria: threats and opportunities
Hemingway, Janet
2014-01-01
Malaria control, and that of other insect borne diseases such as dengue, is heavily dependent on our ability to control the mosquito populations that transmit these diseases. The major push over the last decade to reduce the global burden of malaria has been driven by the distribution of pyrethroid insecticide-treated bednets and an increase in coverage of indoor residual spraying (IRS). This has reduced malaria deaths by a third. Progress towards the goal of reducing this further is threatened by lack of funding and the selection of drug and insecticide resistance. When malaria control was initially scaled up, there was little pyrethroid resistance in the major vectors, today there is no country in Africa where the vectors remain fully susceptible to pyrethroids. The first pyrethroid resistance mechanisms to be selected produced low-level resistance which had little or no operational significance. More recently, metabolically based resistance has been selected, primarily in West Africa, which in some mosquito populations produces more than 1000-fold resistance. As this spreads the effectiveness of pyrethroid-based bednets and IRS will be compromised. New public health insecticides are not readily available. The pipeline of agrochemical insecticides that can be re-purposed for public health dried up 30 years ago when the target product profile for agricultural insecticides shifted from broad spectrum, stable, contact-acting insecticides to narrow spectrum stomach poisons that could be delivered through the plant. A public–private partnership, the Innovative Vector Control Consortium, was established in 2005 to stimulate the development of new public health pesticides. Nine potential new classes of chemistry are in the pipeline, with the intention of developing three into new insecticides. While this has been successfully achieved, it will still take 6–9 years for new insecticides to reach the market. Careful management of the resistance situation in the interim
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Escalante, Ananias A; Ferreira, Marcelo U; Vinetz, Joseph M; Volkman, Sarah K; Cui, Liwang; Gamboa, Dionicia; Krogstad, Donald J; Barry, Alyssa E; Carlton, Jane M; van Eijk, Anna Maria; Pradhan, Khageswar; Mueller, Ivo; Greenhouse, Bryan; Pacheco, M Andreina; Vallejo, Andres F; Herrera, Socrates; Felger, Ingrid
2015-09-01
Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts. © The American Society of Tropical Medicine and Hygiene.
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Walking or Waiting? Topologies of the Breeding Ground in Malaria Control
Lezaun, Javier
2013-01-01
Few places bear as much historical and scientific significance as the breeding ground, the accumulation of stagnant water where disease-carrying insects lay their eggs. Since the turn of the twentieth century, when mosquitoes of the Anopheles genus were identified as the vector of malaria transmission, these aquatic habitats have been a key object of epidemiological research and public health intervention against the disease. Yet the breeding ground can be incorporated into a number of different topologies, each implying a different spatialization of malaria and a distinct imagination of what kind of mosquito control is ‘doable'. A contemporary example of malaria control in Dar es Salaam, Tanzania, illuminates an essential tension between what we characterize as territorial and bionomic approaches to the breeding ground—that is, between control strategies premised on treating all mosquito habitats within a given region, and those that prioritize certain sites on the basis of their position within ecological networks. Each topology localizes the breeding ground by reference to a distinct set of relations, and thus advances an idiosyncratic understanding of what sort of research is worthwhile conducting and what kinds of intervention are sustainable. The multiple ways in which the breeding ground can become an object of research and action clarifies the role of topology as an infra-logic of public health, and makes explicit the politics implicit in efforts to bring different orders of the local to scale. PMID:25937707
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2013-01-01
Background The last decade has witnessed increased funding for malaria control. Malaria experts have used the opportunity to advocate for rollout of such interventions as free bed nets. A free bed net distribution strategy is seen as the quickest way to improve coverage of effective malaria control tools especially among poorest communities. Evidence to support this claim is however, sparse. This study explored the effectiveness of targeted free bed net distribution strategy in achieving equity in terms of ownership and use of bed nets and also reduction of malaria prevalence among children under-five years of age. Methods National malaria indicator survey (MIS) data from Angola, Tanzania and Uganda was used in the analysis. Hierarchical multilevel logistic regression models were used to analyse the relationship between variables of interest. Outcome variables were defined as: childhood test-confirmed malaria infections, household ownership of any mosquito net and children’s use of any mosquito nets. Marginal effects of having free bed net distribution on households with different wealth status were calculated. Results Angolan children from wealthier households were 6.4 percentage points less likely to be parasitaemic than those in poorest households, whereas those from Tanzania and Uganda were less likely to test malaria positive by 7 and 11.6 percentage points respectively (p < 0.001). The study estimates and present results on the marginal effects based on the impact of free bed net distribution on children's malaria status given their socio-economic background. Poorest households were less likely to own a net by 21.4% in Tanzania, and 2.8% in Uganda, whereas both poorer and wealthier Angolan households almost achieved parity in bed net ownership (p < 0.001). Wealthier households had a higher margin of using nets than poorest people in both Tanzania and Uganda by 11.4% and 3.9% respectively. However, the poorest household in Angola had a 6.1% net use
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Impact of Pregnancy-Associated Malaria on Infant Malaria Infection in Southern Benin
Borgella, Sophie; Fievet, Nadine; Huynh, Bich-Tram; Ibitokou, Samad; Hounguevou, Gbetognon; Affedjou, Jacqueline; Sagbo, Jean-Claude; Houngbegnon, Parfait; Guezo-Mévo, Blaise; Massougbodji, Achille; Luty, Adrian J. F.
2013-01-01
Background Infants of mothers with placental Plasmodium falciparum infections at delivery are themselves more susceptible to malaria attacks or to infection in early life. Methodology/ Principal Findings To assess the impact of either the timing or the number of pregnancy-associated malaria (PAM) infections on the incidence of parasitemia or malaria attacks in infancy, we followed 218 mothers through pregnancy (monthly visits) up to delivery and their infants from birth to 12 months of age (fortnightly visits), collecting detailed clinical and parasitological data. After adjustment on location, mother’s age, birth season, bed net use, and placental malaria, infants born to a mother with PAM during the third trimester of pregnancy had a significantly increased risk of infection (OR [95% CI]: 4.2 [1.6; 10.5], p = 0.003) or of malaria attack (4.6 [1.7; 12.5], p = 0.003). PAM during the first and second trimesters had no such impact. Similarly significant results were found for the effect of the overall number of PAM episodes on the time to first parasitemia and first malaria attack (HR [95% CI]: 2.95 [1.58; 5.50], p = 0.001 and 3.19 [1.59; 6.38], p = 0.001) respectively. Conclusions/ Significance This study highlights the importance of protecting newborns by preventing repeated episodes of PAM in their mothers. PMID:24236190
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Snow, Robert W.; Amratia, Punam; Zamani, Ghasem; Mundia, Clara W.; Noor, Abdisalan M.; Memish, Ziad A.; Al Zahrani, Mohammad H.; Al Jasari, Adel; Fikri, Mahmoud; Atta, Hoda
2014-01-01
The transmission of malaria across the Arabian Peninsula is governed by the diversity of dominant vectors and extreme aridity. It is likely that where malaria transmission was historically possible it was intense and led to a high disease burden. Here, we review the speed of elimination, approaches taken, define the shrinking map of risk since 1960 and discuss the threats posed to a malaria-free Arabian Peninsula using the archive material, case data and published works. From as early as the 1940s, attempts were made to eliminate malaria on the peninsula but were met with varying degrees of success through to the 1970s; however, these did result in a shrinking of the margins of malaria transmission across the peninsula. Epidemics in the 1990s galvanised national malaria control programmes to reinvigorate control efforts. Before the launch of the recent global ambition for malaria eradication, countries on the Arabian Peninsula launched a collaborative malaria-free initiative in 2005. This initiative led a further shrinking of the malaria risk map and today locally acquired clinical cases of malaria are reported only in Saudi Arabia and Yemen, with the latter contributing to over 98% of the clinical burden. PMID:23548086
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Falade, Catherine O.; Ajayi, IkeOluwapo O.; Nsungwa-Sabiiti, Jesca; Siribié, Mohamadou; Diarra, Amidou; Sermé, Luc; Afonne, Chinenye; Yusuf, Oyindamola B.; Gansane, Zakaria; Jegede, Ayodele S.; Singlovic, Jan; Gomes, Melba
2016-01-01
Background. The World Health Organization recommends that malaria treatment be based on demonstration of the infecting Plasmodium parasite specie. Malaria rapid diagnostic tests (RDTs) are recommended at community points of care because they are accurate and rapid. We report on parasitological results in a malaria study in selected rural communities in 3 African countries. Methods. In Nigeria, community health workers (CHWs) performed RDTs (SD-Bioline) and thick blood smears on all children suspected to have malaria. Malaria RDT-positive children able to swallow received artemisinin-based combination therapy (Coartem). In all countries, children unable to take oral drugs received prereferral rectal artesunate irrespective of RDT result and were referred to the nearest health facility. Thick blood smears and RDTs were usually taken at hospital admission. In Nigeria and Burkina Faso, RDT cassettes and blood smears were re-read by an experienced investigator at study end. Results. Trained CHWs enrolled 2148 children in Nigeria. Complete parasitological data of 1860 (86.6%) enrollees were analyzed. The mean age of enrollees was 30.4 ± 15.7 months. The prevalence of malaria parasitemia in the study population was 77.8% (1447/1860), 77.6% (1439/1855), and 54.1% (862/1593) by RDT performed by CHWs vs an expert clinical research assistant vs microscopy (gold standard), respectively. Geometric mean parasite density was 6946/µL (range, 40–436 450/µL). There were 49 cases of RDT false-negative results with a parasite density range of 40–54 059/µL. False-negative RDT results with high parasitemia could be due to non-falciparum infection or result from a prozone effect. Sensitivity and specificity of SD-Bioline RDT results as read by CHWs were 94.3% and 41.6%, respectively, while the negative and positive predictive values were 86.1% and 65.6%, respectively. The level of agreement in RDT reading by the CHWs and experienced research staff was 86.04% and κ
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Alvarado, Beatriz Eugenia; Alzate, Alberto; Mateus, Julio Cesar; Carvajal, Rocío
2006-09-01
A four-component, non randomized, primary-care based intervention for malaria control was implemented in Buenaventura, Colombia. To evaluate the effect of the applied intervention on knowledge about malaria, attention of febrile events and frequency of malaria occurrence in three communities of Buenaventura. A post-intervention evaluation with a non-equivalent control group was performed. Two non-intervened groups (those residing more and less than six months, respectively, in the area) and one intervened group were identified. We interviewed 661 women household heads. Contact was defined as having been exposed to at least one of the four intervention components. Fourteen percent of the respondents had contact with the intervention. The attention of a febrile episode was better in those who had contact with the intervention than in the nonintervened ones who had resided in the area for more than six months. Those without contact and with less than six months stay in the area reported lower use of bed-nets (OR:0.46; 95% CI:0.23-0.93) and less fumigation practices (OR:0.38; 95% CI:0.19-0.75). The analysis of the malaria case trend showed a reduction in the proportion of cases contributed by the intervened communities, from 25% to 17%, six years after the intervention. An educational strategy is effective to enhance knowledge and modify the practices of the urban population of Buenaventura with respect to malaria.
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Rapid urban malaria appraisal (RUMA) in sub-Saharan Africa
Wang, Shr-Jie; Lengeler, Christian; Smith, Thomas A; Vounatsou, Penelope; Cissé, Guéladio; Diallo, Diadie A; Akogbeto, Martin; Mtasiwa, Deo; Teklehaimanot, Awash; Tanner, Marcel
2005-01-01
Background The rapid urban malaria appraisal (RUMA) methodology aims to provide a cost-effective tool to conduct rapid assessments of the malaria situation in urban sub-Saharan Africa and to improve the understanding of urban malaria epidemiology. Methods This work was done in Yopougon municipality (Abidjan), Cotonou, Dar es Salaam and Ouagadougou. The study design consists of six components: 1) a literature review, 2) the collection of available health statistics, 3) a risk mapping, 4) school parasitaemia surveys, 5) health facility-based surveys and 6) a brief description of the health care system. These formed the basis of a multi-country evaluation of RUMA's feasibility, consistency and usefulness. Results A substantial amount of literature (including unpublished theses and statistics) was found at each site, providing a good overview of the malaria situation. School and health facility-based surveys provided an overview of local endemicity and the overall malaria burden in different city areas. This helped to identify important problems for in-depth assessment, especially the extent to which malaria is over-diagnosed in health facilities. Mapping health facilities and breeding sites allowed the visualization of the complex interplay between population characteristics, health services and malaria risk. However, the latter task was very time-consuming and required special expertise. RUMA is inexpensive, costing around 8,500–13,000 USD for a six to ten-week period. Conclusion RUMA was successfully implemented in four urban areas with different endemicity and proved to be a cost-effective first approach to study the features of urban malaria and provide an evidence basis for planning control measures. PMID:16153298
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McCann, Robert S; van den Berg, Henk; Diggle, Peter J; van Vugt, Michèle; Terlouw, Dianne J; Phiri, Kamija S; Di Pasquale, Aurelio; Maire, Nicolas; Gowelo, Steven; Mburu, Monicah M; Kabaghe, Alinune N; Mzilahowa, Themba; Chipeta, Michael G; Takken, Willem
2017-09-22
Due to outdoor and residual transmission and insecticide resistance, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) will be insufficient as stand-alone malaria vector control interventions in many settings as programmes shift toward malaria elimination. Combining additional vector control interventions as part of an integrated strategy would potentially overcome these challenges. Larval source management (LSM) and structural house improvements (HI) are appealing as additional components of an integrated vector management plan because of their long histories of use, evidence on effectiveness in appropriate settings, and unique modes of action compared to LLINs and IRS. Implementation of LSM and HI through a community-based approach could provide a path for rolling-out these interventions sustainably and on a large scale. We will implement community-based LSM and HI, as additional interventions to the current national malaria control strategies, using a randomised block, 2 × 2 factorial, cluster-randomised design in rural, southern Malawi. These interventions will be continued for two years. The trial catchment area covers about 25,000 people living in 65 villages. Community participation is encouraged by training community volunteers as health animators, and supporting the organisation of village-level committees in collaboration with The Hunger Project, a non-governmental organisation. Household-level cross-sectional surveys, including parasitological and entomological sampling, will be conducted on a rolling, 2-monthly schedule to measure outcomes over two years (2016 to 2018). Coverage of LSM and HI will also be assessed throughout the trial area. Combining LSM and/or HI together with the interventions currently implemented by the Malawi National Malaria Control Programme is anticipated to reduce malaria transmission below the level reached by current interventions alone. Implementation of LSM and HI through a community
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Matsiégui, Pierre-Blaise; Missinou, Michel A; Necek, Magdalena; Mavoungou, Elie; Issifou, Saadou; Lell, Bertrand; Kremsner, Peter G
2008-01-01
Background Antipyretic drugs are widely used in children with fever, though there is a controversy about the benefit of reducing fever in children with malaria. In order to assess the effect of ibuprofen on fever compared to placebo in children with uncomplicated Plasmodium falciparum malaria in Gabon, a randomized double blind placebo controlled trial, was designed. Methods Fifty children between two and seven years of age with uncomplicated malaria were included in the study. For the treatment of fever, all patients "received" mechanical treatment when the temperature rose above 37.5°C. In addition to the mechanical treatment, continuous fanning and cooling blanket, patients were assigned randomly to receive ibuprofen (7 mg/kg body weight, every eight hours) or placebo. Results The fever clearance time using a fever threshold of 37.5°C was similar in children receiving ibuprofen compared to those receiving placebo. The difference was also not statistically significant using a fever threshold of 37.8°C or 38.0°C. However, the fever time and the area under the fever curve were significantly smaller in the ibuprofen group compared to the placebo group. Conclusion Ibuprofen is effective in reducing the time with fever. The effect on fever clearance is less obvious and depends on definition of the fever threshold. Trial registration The trial registration number is: NCT00167713 PMID:18503714
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2013-01-01
Background Malaria is a leading cause of morbidity and mortality, with approximately 225 million clinical episodes and >1.2 million deaths annually attributed to malaria. Development of a highly efficacious malaria vaccine will offer unparalleled possibilities for disease prevention and remains a key priority for long-term malaria control and elimination. Discussion The Malaria Vaccine Technology Roadmap’s goal is to 'develop and license a first-generation malaria vaccine that has protective efficacy of more than 50%’. To date, malaria vaccine candidates have only been shown to be partially efficacious (approximately 30% to 60%). However, licensure of a partially effective vaccine will create a number of challenges for the development and progression of new, potentially more efficacious, malaria vaccines in the future. In this opinion piece we discuss the methodological, logistical and ethical issues that may impact on the feasibility and implementation of superiority, non-inferiority and equivalence trials to assess second generation malaria vaccines in the advent of the licensure of a partially efficacious malaria vaccine. Conclusions Selecting which new malaria vaccines go forward, and defining appropriate methodology for assessment in logistically challenging clinical trials, is crucial. It is imperative that the scientific community considers all the issues and starts planning how second-generation malaria vaccines will advance in the advent of licensure of a partially effective vaccine. PMID:24228861
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Malaria in the Greater Mekong Subregion: Heterogeneity and Complexity
Cui, Liwang; Yan, Guiyun; Sattabongkot, Jetsumon; Cao, Yaming; Chen, Bin; Chen, Xiaoguang; Fan, Qi; Fang, Qiang; Jongwutiwes, Somchai; Parker, Daniel; Sirichaisinthop, Jeeraphat; Kyaw, Myat Phone; Su, Xin-zhuan; Yang, Henglin; Yang, Zhaoqing; Wang, Baomin; Xu, Jianwei; Zheng, Bin; Zhong, Daibin; Zhou, Guofa
2011-01-01
The Greater Mekong Subregion (GMS), comprised of six countries including Cambodia, China's Yunnan Province, Lao PDR, Myanmar (Burma), Thailand and Vietnam, is one of the most threatening foci of malaria. Since the initiation of the WHO's Mekong Malaria Program a decade ago, malaria situation in the GMS has greatly improved, reflected in the continuous decline in annual malaria incidence and deaths. However, as many nations are moving towards malaria elimination, the GMS nations still face great challenges. Malaria epidemiology in this region exhibits enormous geographical heterogeneity with Myanmar and Cambodia remaining high-burden countries. Within each country, malaria distribution is also patchy, exemplified by ‘border malaria’ and ‘forest malaria’ with high transmission occurring along international borders and in forests or forest fringes, respectively. ‘Border malaria’ is extremely difficult to monitor, and frequent malaria introductions by migratory human populations constitute a major threat to neighboring, malaria-eliminating countries. Therefore, coordination between neighboring countries is essential for malaria elimination from the entire region. In addition to these operational difficulties, malaria control in the GMS also encounters several technological challenges. Contemporary malaria control measures rely heavily on effective chemotherapy and insecticide control of vector mosquitoes. However, the spread of multidrug resistance and potential emergence of artemisinin resistance in Plasmodium falciparum make resistance management a high priority in the GMS. This situation is further worsened by the circulation of counterfeit and substandard artemisinin-related drugs. In most endemic areas of the GMS, P. falciparum and P. vivax coexist, and in recent malaria control history, P. vivax has demonstrated remarkable resilience to control measures. Deployment of the only registered drug (primaquine) for the radical cure of vivax malaria is
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Declining malaria, rising of dengue and Zika virus: insights for mosquito vector control.
Benelli, Giovanni; Mehlhorn, Heinz
2016-05-01
The fight against mosquito-borne diseases is a challenge of huge public health importance. To our mind, 2015 was an extraordinary year for malaria control, due to three hot news: the Nobel Prize to Youyou Tu for the discovery of artemisinin, the development of the first vaccine against Plasmodium falciparum malaria [i.e. RTS,S/AS01 (RTS,S)], and the fall of malaria infection rates worldwide, with special reference to sub-Saharan Africa. However, there are major challenges that still deserve attention, in order to boost malaria prevention and control. Indeed, parasite strains resistant to artemisinin have been detected, and RTS,S vaccine does not offer protection against Plasmodium vivax malaria, which predominates in many countries outside of Africa. Furthermore, the recent outbreaks of Zika virus infections, occurring in South America, Central America and the Caribbean, represent the most recent of four arrivals of important arboviruses in the Western Hemisphere, over the last 20 years. Zika virus follows dengue (which slyly arrived in the hemisphere over decades and became more aggressive in the 1990s), West Nile virus (emerged in 1999) and chikungunya (emerged in 2013). Notably, there are no specific treatments for these arboviruses. The emerging scenario highlights that the effective and eco-friendly control of mosquito vectors, with special reference to highly invasive species such as Aedes aegypti and Aedes albopictus, is crucial. The concrete potential of screening plant species as sources of metabolites for parasitological purposes is worthy of attention, as elucidated by the Y. Tu's example. Notably, plant-borne molecules are often effective at few parts per million against Aedes, Ochlerotatus, Anopheles and Culex young instars, can be used for the rapid synthesis of mosquitocidal nanoformulations and even employed to prepare cheap repellents with low human toxicity. In addition, behaviour-based control tools relying to the employ of sound traps and the
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Malaria in Sucre State, Venezuela.
Zimmerman, R H
2000-01-01
The author reviews the malaria research program in Sucre State, Venezuela, taking an ecosystem approach. The goal was to determine which methods could have been introduced at the onset that would have made the study more ecological and interdisciplinary. Neither an ecosystem approach nor integrated disease control were in place at the time of the study. This study began to introduce an ecosystem approach when two contrasting ecosystems in Sucre State were selected for study and vector control methods were implemented based on research results. The need to have a health policy in place with an eco-health approach is crucial to the success of research and control. The review suggests that sustainability is low when not all the stakeholders are involved in the design and implementation of the research and control strategy development. The lack of community involvement makes sustainability doubtful. The author concludes that there were two interdependent challenges for malaria control: development of an ecosystem approach for malaria research and control, and the implementation of an integrated disease control strategy, with malaria as one of the important health issues.
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Yé, Yazoume; Eisele, Thomas P; Eckert, Erin; Korenromp, Eline; Shah, Jui A; Hershey, Christine L; Ivanovich, Elizabeth; Newby, Holly; Carvajal-Velez, Liliana; Lynch, Michael; Komatsu, Ryuichi; Cibulskis, Richard E; Moore, Zhuzhi; Bhattarai, Achuyt
2017-09-01
Concerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in sub-Saharan Africa (SSA). This scale-up warrants an assessment of its health impact to guide future efforts and investments; however, measuring malaria-specific mortality and the overall impact of malaria control interventions remains challenging. In 2007, Roll Back Malaria's Monitoring and Evaluation Reference Group proposed a theoretical framework for evaluating the impact of full-coverage malaria control interventions on morbidity and mortality in high-burden SSA countries. Recently, several evaluations have contributed new ideas and lessons to strengthen this plausibility design. This paper harnesses that new evaluation experience to expand the framework, with additional features, such as stratification, to examine subgroups most likely to experience improvement if control programs are working; the use of a national platform framework; and analysis of complete birth histories from national household surveys. The refined framework has shown that, despite persisting data challenges, combining multiple sources of data, considering potential contributions from both fundamental and proximate contextual factors, and conducting subnational analyses allows identification of the plausible contributions of malaria control interventions on malaria morbidity and mortality.
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Yé, Yazoume; Eisele, Thomas P.; Eckert, Erin; Korenromp, Eline; Shah, Jui A.; Hershey, Christine L.; Ivanovich, Elizabeth; Newby, Holly; Carvajal-Velez, Liliana; Lynch, Michael; Komatsu, Ryuichi; Cibulskis, Richard E.; Moore, Zhuzhi; Bhattarai, Achuyt
2017-01-01
Abstract. Concerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in sub-Saharan Africa (SSA). This scale-up warrants an assessment of its health impact to guide future efforts and investments; however, measuring malaria-specific mortality and the overall impact of malaria control interventions remains challenging. In 2007, Roll Back Malaria's Monitoring and Evaluation Reference Group proposed a theoretical framework for evaluating the impact of full-coverage malaria control interventions on morbidity and mortality in high-burden SSA countries. Recently, several evaluations have contributed new ideas and lessons to strengthen this plausibility design. This paper harnesses that new evaluation experience to expand the framework, with additional features, such as stratification, to examine subgroups most likely to experience improvement if control programs are working; the use of a national platform framework; and analysis of complete birth histories from national household surveys. The refined framework has shown that, despite persisting data challenges, combining multiple sources of data, considering potential contributions from both fundamental and proximate contextual factors, and conducting subnational analyses allows identification of the plausible contributions of malaria control interventions on malaria morbidity and mortality. PMID:28990923
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2013-01-01
Background Malaria in pregnancy (MiP) is a major public health problem in endemic areas of sub-Saharan Africa and has important consequences on birth outcome. Because MiP is a complex phenomenon and malaria epidemiology is rapidly changing, additional evidence is still required to understand how best to control malaria. This study followed a prospective cohort of pregnant women who had access to intensive malaria screening and prompt treatment to identify factors associated with increased risk of MiP and to analyse how various characteristics of MiP affect delivery outcomes. Methods Between October 2006 and May 2009, 1,218 pregnant women were enrolled in a prospective cohort. After an initial assessment, they were screened weekly for malaria. At delivery, blood smears were obtained from the mother, placenta, cord and newborn. Multivariate analyses were performed to analyse the association between mothers’ characteristics and malaria risk, as well as between MiP and birth outcome, length and weight at birth. This study is a secondary analysis of a trial registered with ClinicalTrials.gov, number NCT00495508. Results Overall, 288/1,069 (27%) mothers had 345 peripheral malaria infections. The risk of peripheral malaria was higher in mothers who were younger, infected with HIV, had less education, lived in rural areas or reported no bed net use, whereas the risk of placental infection was associated with more frequent malaria infections and with infection during late pregnancy. The risk of pre-term delivery and of miscarriage was increased in mothers infected with HIV, living in rural areas and with MiP occurring within two weeks of delivery. In adjusted analysis, birth weight but not length was reduced in babies of mothers exposed to MiP (−60g, 95%CI: -120 to 0 for at least one infection and -150 g, 95%CI: -280 to −20 for >1 infections). Conclusions In this study, the timing, parasitaemia level and number of peripherally-detected malaria infections, but not the
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Barrenho, Eliana; Miraldo, Marisa; Shaikh, Mujaheed; Atun, Rifat
2017-01-01
Background International and domestic funding for malaria is critically important to achieve the Sustainable Development Goals. Its equitable distribution is key in ensuring that the available, scarce, resources are deployed efficiently for improved progress and a sustained response that enables eradication. Methods We used concentration curves and concentration indices to assess inequalities in malaria funding by different donors across countries, measuring both horizontal and vertical equity. Horizontal equity assesses whether funding is distributed in proportion to health needs, whereas vertical equity examines whether unequal economic needs are addressed by appropriately unequal funding. We computed the Health Inequity Index and the Kakwani Index to assess the former and the latter, respectively. We used data from the World Bank, Global Fund, Unicef, President’s Malaria Initiative and the Malaria Atlas Project to assess the distribution of funding against need for 94 countries. National gross domestic product per capita was used as a proxy for economic need and ‘population-at-risk’ for health need. Findings The level and direction of inequity varies across funding sources. Unicef and the President’s Malaria Initiative were the most horizontally inequitable (pro-poor). Inequity as shown by the Health Inequity Index for Unicef decreased from −0.40 (P<0.05) in 2006 to −0.25 (P<0.10) in 2008, and increased again to −0.58 (P<0.01) in 2009. For President’s Malaria Initiative, it increased from −0.19 (P>0.10) in 2006 to −0.38 (P<0.05) in 2008, and decreased to −0.36 (P<0.10) in 2010. Domestic funding was inequitable (pro-rich) with inequity increasing from 0.28 (P<0.01) in 2006 to 0.39 (P<0.01) in 2009, and then decreasing to 0.22 (P<0.10) in 2010. Funding from the World Bank and the Global Fund was distributed proportionally according to need. In terms of vertical inequity, all sources were progressive: Unicef and the President’s Malaria
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Zhang, Qian; Lai, Shengjie; Zheng, Canjun; Zhang, Honglong; Zhou, Sheng; Hu, Wenbiao; Clements, Archie C A; Zhou, Xiao-Nong; Yang, Weizhong; Hay, Simon I; Yu, Hongjie; Li, Zhongjie
2014-11-03
In China, the national malaria elimination programme has been operating since 2010. This study aimed to explore the epidemiological changes in patterns of malaria in China from intensified control to elimination stages. Data on nationwide malaria cases from 2004 to 2012 were extracted from the Chinese national malaria surveillance system. The secular trend, gender and age features, seasonality, and spatial distribution by Plasmodium species were analysed. In total, 238,443 malaria cases were reported, and the proportion of Plasmodium falciparum increased drastically from <10% before 2010 to 55.2% in 2012. From 2004 to 2006, malaria showed a significantly increasing trend and with the highest incidence peak in 2006 (4.6/100,000), while from 2007 onwards, malaria decreased sharply to only 0.18/100,000 in 2012. Males and young age groups became the predominantly affected population. The areas affected by Plasmodium vivax malaria shrunk, while areas affected by P. falciparum malaria expanded from 294 counties in 2004 to 600 counties in 2012. This study demonstrated that malaria has decreased dramatically in the last five years, especially since the Chinese government launched a malaria elimination programme in 2010, and areas with reported falciparum malaria cases have expanded over recent years. These findings suggest that elimination efforts should be improved to meet these changes, so as to achieve the nationwide malaria elimination goal in China in 2020.
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Malaria control along China-Myanmar Border during 2007-2013: an integrated impact evaluation.
Xu, Jian-Wei; Li, Yong; Yang, Heng-Lin; Zhang, Jun; Zhang, Zai-Xing; Yang, Ya-Ming; Zhou, Hong-Ning; Havumaki, Joshua; Li, Hua-Xian; Liu, Hui; Zhou, Hua; Xie, Xin-Yu; Dong, Jia-Xiang; Zhang, Yue; Sun, Xiao-Ying; Li, Bo; Li, Jia-Yin; Tian, Yang-Hui; Wang, Pi-Yu; Li, Ben-Fu
2016-08-10
Implementing effective interventions remain a lot of difficulties along all border regions. The emergence of artemisinin resistance of Plasmodium falciparum strains in the Greater Mekong Subregion is a matter of great concern. China has effectively controlled cross-border transmission of malaria and artemisinin resistance of P. falciparum along the China-Myanmar border. A combined quantitative and qualitative study was used to collect data, and then an integrated impact evaluation was conducted to malaria control along the China-Myanmar border during 2007-2013. The parasite prevalence rate (PPR) in the five special regions of Myanmar was decreased from 13.6 % in March 2008 to 1.5 % in November 2013. Compared with the baseline (PPR in March 2008), the risk ratio was only 0.11 [95 % confidence interval (CI), 0.09-0. 14) in November 2013, which is equal to an 89 % reduction in the malaria burden. Annual parasite incidence (API) across 19 Chinese border counties was reduced from 19.6 per 10 000 person-years in 2006 to 0.9 per 10 000 person-years in 2013. Compared with the baseline (API in 2006), the API rate ratio was only 0.05(95 % CI, 0.04-0.05) in 2013, which equates to a reduction of the malaria burden by 95.0 %. Meanwhile, the health service system was strengthened and health inequity of marginalized populations reduced along the international border. The effective collaboration between China, Myanmar and the international non-governmental organization promptly carried out the core interventions through simplified processes. The integrated approaches dramatically decreased malaria burden of Chinese-Myanmar border.
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Bradley, John; Knight, Philip; Stone, William; Osoti, Victor; Makori, Euniah; Owaga, Chrispin; Odongo, Wycliffe; China, Pauline; Shagari, Shehu; Doumbo, Ogobara K.; Sauerwein, Robert W.; Kariuki, Simon; Drakeley, Chris; Stevenson, Jennifer; Cox, Jonathan
2016-01-01
Background Malaria transmission is highly heterogeneous, generating malaria hotspots that can fuel malaria transmission across a wider area. Targeting hotspots may represent an efficacious strategy for reducing malaria transmission. We determined the impact of interventions targeted to serologically defined malaria hotspots on malaria transmission both inside hotspots and in surrounding communities. Methods and Findings Twenty-seven serologically defined malaria hotspots were detected in a survey conducted from 24 June to 31 July 2011 that included 17,503 individuals from 3,213 compounds in a 100-km2 area in Rachuonyo South District, Kenya. In a cluster-randomized trial from 22 March to 15 April 2012, we randomly allocated five clusters to hotspot-targeted interventions with larviciding, distribution of long-lasting insecticide-treated nets, indoor residual spraying, and focal mass drug administration (2,082 individuals in 432 compounds); five control clusters received malaria control following Kenyan national policy (2,468 individuals in 512 compounds). Our primary outcome measure was parasite prevalence in evaluation zones up to 500 m outside hotspots, determined by nested PCR (nPCR) at baseline and 8 wk (16 June–6 July 2012) and 16 wk (21 August–10 September 2012) post-intervention by technicians blinded to the intervention arm. Secondary outcome measures were parasite prevalence inside hotpots, parasite prevalence in the evaluation zone as a function of distance from the hotspot boundary, Anopheles mosquito density, mosquito breeding site productivity, malaria incidence by passive case detection, and the safety and acceptability of the interventions. Intervention coverage exceeded 87% for all interventions. Hotspot-targeted interventions did not result in a change in nPCR parasite prevalence outside hotspot boundaries (p ≥ 0.187). We observed an average reduction in nPCR parasite prevalence of 10.2% (95% CI −1.3 to 21.7%) inside hotspots 8 wk post
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Seasonal genetic partitioning in the neotropical malaria vector, Anopheles darlingi
2014-01-01
Background Anopheles darlingi is the main malaria mosquito vector in the Amazonia region. In spite of being considered a riverine, forest-dwelling species, this mosquito is becoming more abundant in peri-urban areas, increasing malaria risk. This has been associated with human-driven environmental changes such as deforestation. Methods Microsatellites were used to characterize A. darlingi from seven localities along the Madeira River, Rondônia (Brazil), collected in the early and late periods of the rainy season. Results Two genetically distinct subpopulations were detected: one (subpopulation A) was associated with the late rainfall period and seems to be ecologically closer to the typical forest A. darlingi; the other (subpopulation B) was associated with the early rainfall period and is probably more adapted to drier conditions by exploiting permanent anthropogenic breeding sites. Results suggest also a pattern of asymmetric introgression, with more subpopulation A alleles introgressed into subpopulation B. Both subpopulations (and admixed mosquitoes) presented similar malaria infection rates, highlighting the potential for perennial malaria transmission in the region. Conclusions The co-occurrence of two genetically distinct subpopulations of A. darlingi adapted to different periods of rainfall may promote a more perennial transmission of malaria throughout the year. These findings, in a context of strong environmental impact due to deforestation and dam construction, have serious implications for malaria epidemiology and control in the Amazonian region. PMID:24885508
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Backward bifurcation and optimal control of Plasmodium Knowlesi malaria
NASA Astrophysics Data System (ADS)
Abdullahi, Mohammed Baba; Hasan, Yahya Abu; Abdullah, Farah Aini
2014-07-01
A deterministic model for the transmission dynamics of Plasmodium Knowlesi malaria with direct transmission is developed. The model is analyzed using dynamical system techniques and it shows that the backward bifurcation occurs for some range of parameters. The model is extended to assess the impact of time dependent preventive (biological and chemical control) against the mosquitoes and vaccination for susceptible humans, while treatment for infected humans. The existence of optimal control is established analytically by the use of optimal control theory. Numerical simulations of the problem, suggest that applying the four control measure can effectively reduce if not eliminate the spread of Plasmodium Knowlesi in a community.
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Baiden, Frank; Webster, Jayne; Tivura, Mathilda; Delimini, Rupert; Berko, Yvonne; Amenga-Etego, Seeba; Agyeman-Budu, Akua; Karikari, Akosua B.; Bruce, Jane; Owusu-Agyei, Seth; Chandramohan, Daniel
2012-01-01
Background WHO now recommends test-based management of malaria across all transmission settings. The accuracy of rapid diagnostic test (RDT) and the outcome of treatment based on the result of tests will influence acceptability of and adherence to the new guidelines. Method We conducted a study at the Kintampo hospital in rural Ghana to evaluate the performance of CareStart, a HRP-2 based RDT, using microscopy as reference. We applied IMCI treatment guidelines, restricted ACT to RDT-positive children and followed-up both RDT-positive (malaria) and RDT-negative (non-malaria) cases over 28 days. Results 436 children were enrolled in the RDT evaluation and 391 (children with haemoglobin >8.0 gm/dl) were followed-up to assess treatment outcomes. Mean age was 25.4 months (s.d. 14.6). Sensitivity and specificity of the RDT were 100.0% and 73.0% respectively. Over the follow-up period, 32 (18.5%) RDT-negative children converted to positive, with 7 (4.0%) of them presenting with fever. More children in the non-malaria group made unscheduled visits than children in the malaria group (13.3% versus 7.7%) On all scheduled follow-up visits, proportion of children having a temperature higher than that recorded on day 0 was higher in the non-malaria group compared to the malaria group. Reports of unfavourable treatment outcomes by caregivers were higher among the non-malaria group than the malaria group. Conclusions The RDT had good sensitivity and specificity. However a minority of children who will not receive ACT based on RDT results may develop clinical malaria within a short period in high transmission settings. This could undermine caregivers' and health workers' confidence in the new guidelines. Improving the quality of management of non-malarial febrile illnesses should be a priority in the era of test-based management of malaria. Trial Registration ClinicalTrials.gov NCT00832754 PMID:22514617
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Controlling Malaria and Other Diseases Using Remote Sensing
NASA Technical Reports Server (NTRS)
Kiang, Richard K.; Wharton, Stephen W. (Technical Monitor)
2001-01-01
Remote sensing offers the vantage of monitoring a vast area of the Earth continuously. Once developed and launched, a satellite gives years of service in collecting data from the land, the oceans, and the atmosphere. Since the 1980s, attempts have been made to relate disease occurrence with remotely sensed environmental and geophysical parameters, using data from Landsat, SPOT, AVHRR, and other satellites. With higher spatial resolution, the recent satellite sensors provide a new outlook for disease control. At sub-meter to I 10m resolution, surface types associated with disease carriers can be identified more accurately. The Ikonos panchromatic sensor with I m resolution, and the Advanced Land Imager with 1 Om resolution on the newly launched Earth Observing-1, both have displayed remarkable mapping capabilities. In addition, an entire array of geophysical parameters can now be measured or inferred from various satellites. Airborne remote sensing, with less concerns on instrument weight, size, and power consumption, also offers a low-cost alternative for regional applications. NASA/GSFC began to collaborate with the Mahidol University on malaria and filariasis control using remote sensing in late 2000. The objectives are: (1) To map the breeding sites for the major vector species; (2) To identify the potential sites for larvicide and insecticide applications; (3) To explore the linkage of vector population and transmission intensity to environmental variables; (4) To monitor the impact of climate change and human activities on vector population and transmission; and (5) To develop a predictive model for disease distribution. Field studies are being conducted in several provinces in Thailand. Data analyses will soon begin. Malaria data in South Korea are being used as surrogates for developing classification techniques. GIS has been shown to be invaluable in making the voluminous remote sensing data more readily understandable. It will be used throughout this study
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van Eijk, Anna M; Hill, Jenny; Noor, Abdisalan M; Snow, Robert W; ter Kuile, Feiko O
2015-01-01
Summary Background In malarious areas, pregnant women are more likely to have detectable malaria than are their non-pregnant peers, and the excess risk of infection varies with gravidity. Pregnant women attending antenatal clinic for their first visit are a potential pragmatic sentinel group to track the intensity of malaria transmission; however, the relation between malaria prevalence in children, a standard measure to estimate malaria endemicity, and pregnant women has never been compared. Methods We obtained data on malaria prevalence in pregnancy from the Malaria in Pregnancy Library (January, 2015) and data for children (0–59 months) were obtained from recently published work on parasite prevalence in Africa and the Malaria in Pregnancy Library. We used random effects meta-analysis to obtain a pooled prevalence ratio (PPR) of malaria in children versus pregnant women (during pregnancy, not at delivery) and by gravidity, and we used meta-regression to assess factors affecting the prevalence ratio. Findings We used data from 18 sources that included 57 data points. There was a strong linear relation between the prevalence of malaria infection in pregnant women and children (r=0·87, p<0·0001). Prevalence was higher in children when compared with all gravidae (PPR=1·44, 95% CI 1·29–1·62; I2=80%, 57 studies), and against multigravidae (1·94, 1·68–2·24; I2=80%, 7 studies), and marginally higher against primigravidae (1·16, 1·05–1·29; I2=48%, 8 studies). PPR was higher in areas of higher transmission. Interpretation Malaria prevalence in pregnant women is strongly correlated with prevalence data in children obtained from household surveys, and could provide a pragmatic adjunct to survey strategies to track trends in malaria transmission in Africa. Funding The Malaria in Pregnancy Consortium, which is funded through a grant from the Bill & Melinda Gates Foundation to the Liverpool School of Tropical Medicine, UK; US Centers for Disease Control and
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Manyangadze, Tawanda; Chimbari, Moses J; Macherera, Margaret; Mukaratirwa, Samson
2017-11-21
Although there has been a decline in the number of malaria cases in Zimbabwe since 2010, the disease remains the biggest public health threat in the country. Gwanda district, located in Matabeleland South Province of Zimbabwe has progressed to the malaria pre-elimination phase. The aim of this study was to determine the spatial distribution of malaria incidence at ward level for improving the planning and implementation of malaria elimination in the district. The Poisson purely spatial model was used to detect malaria clusters and their properties, including relative risk and significance levels at ward level. The geographically weighted Poisson regression (GWPR) model was used to explore the potential role and significance of environmental variables [rainfall, minimum and maximum temperature, altitude, Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), rural/urban] and malaria control strategies [indoor residual spraying (IRS) and long-lasting insecticide-treated nets (LLINs)] on the spatial patterns of malaria incidence at ward level. Two significant clusters (p < 0.05) of malaria cases were identified: (1) ward 24 south of Gwanda district and (2) ward 9 in the urban municipality, with relative risks of 5.583 and 4.316, respectively. The semiparametric-GWPR model with both local and global variables had higher performance based on AICc (70.882) compared to global regression (74.390) and GWPR which assumed that all variables varied locally (73.364). The semiparametric-GWPR captured the spatially non-stationary relationship between malaria cases and minimum temperature, NDVI, NDWI, and altitude at the ward level. The influence of LLINs, IRS and rural or urban did not vary and remained in the model as global terms. NDWI (positive coefficients) and NDVI (range from negative to positive coefficients) showed significant association with malaria cases in some of the wards. The IRS had a protection
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Shaukat, Ayesha M; Breman, Joel G; McKenzie, F Ellis
2010-05-12
Prior studies have shown that annual entomological inoculation rates (EIRs) must be reduced to less than one to substantially reduce the prevalence of malaria infection. In this study, EIR values were used to quantify the impact of insecticide-treated bed nets (ITNs), indoor residual spraying (IRS), and source reduction (SR) on malaria transmission. The analysis of EIR was extended through determining whether available vector control tools can ultimately eradicate malaria. The analysis is based primarily on a review of all controlled studies that used ITN, IRS, and/or SR and reported their effects on the EIR. To compare EIRs between studies, the percent difference in EIR between the intervention and control groups was calculated. Eight vector control intervention studies that measured EIR were found: four ITN studies, one IRS study, one SR study, and two studies with separate ITN and IRS intervention groups. In both the Tanzania study and the Solomon Islands study, one community received ITNs and one received IRS. In the second year of the Tanzania study, EIR was 90% lower in the ITN community and 93% lower in the IRS community, relative to the community without intervention; the ITN and IRS effects were not significantly different. In contrast, in the Solomon Islands study, EIR was 94% lower in the ITN community and 56% lower in the IRS community. The one SR study, in Dar es Salaam, reported a lower EIR reduction (47%) than the ITN and IRS studies. All of these vector control interventions reduced EIR, but none reduced it to zero. These studies indicate that current vector control methods alone cannot ultimately eradicate malaria because no intervention sustained an annual EIR less than one. While researchers develop new tools, integrated vector management may make the greatest impact on malaria transmission. There are many gaps in the entomological malaria literature and recommendations for future research are provided.
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Maternal Malaria and Gravidity Interact to Modify Infant Susceptibility to Malaria
Mutabingwa, Theonest K; Bolla, Melissa C; Li, Jin-Long; Domingo, Gonzalo J; Li, Xiaohong; Fried, Michal; Duffy, Patrick E
2005-01-01
Background In endemic areas, placental malaria due to Plasmodium falciparum is most frequent and severe in first-time mothers, and increases the risk of infant mortality in their offspring. Placental malaria may increase the susceptibility of infants to malaria parasitemia, but evidence for this effect is inconclusive. Methods and Findings During 2002–2004, we monitored parasitemia in 453 infants, including 69 who were born to mothers with placental malaria, in a region of northeastern Tanzania where malaria transmission is intense. We used a Cox proportional hazards model to evaluate the time from birth to first parasitemia, and a generalized estimating equations logistic regression model to evaluate risk of any parasitemia throughout the first year of life. Compared with infants whose mothers did not have placental malaria at delivery (“PM-negative”), offspring of mothers with placental malaria at delivery (“PM-positive”) were 41% more likely to experience their first parasitemia at a younger age (adjusted hazard ratio [AHR] = 1.41, 95% confidence interval [CI] 1.01–1.99). The odds of parasitemia throughout infancy were strongly modified by the interaction between placental malaria and gravidity (p for interaction = 0.008, Type 3 likelihood ratio test). Offspring of PM-negative primigravidae had lower odds of parasitemia during infancy (adjusted odds ratio [AOR] = 0.67, 95% CI 0.50–0.91) than offspring of PM-negative multigravidae, and offspring of PM-positive primigravidae had the lowest odds (AOR = 0.21, 95% CI 0.09–0.47). In contrast, offspring of PM-positive multigravidae had significantly higher odds of parasitemia (AOR = 1.59, 95% CI 1.16–2.17). Conclusion Although parasitemia is more frequent in primigravid than multigravid women, the converse is true in their offspring, especially in offspring of PM-positive women. While placental malaria is known to increase mortality risk for first-born infants, it surprisingly reduced their risk of
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Determinants of malaria infection in Dembia district, Northwest Ethiopia: a case-control study.
Agegnehu, Fisseha; Shimeka, Alemayehu; Berihun, Firnus; Tamir, Melkamu
2018-04-11
Despite the progress in reducing malaria infections and related deaths, the disease remains a major global public health problem. The problem is among the top five leading causes of outpatient visits in Dembia district of the northwest Ethiopia. Therefore, this study aimed to assess the determinants of malaria infections in the district. An institution-based case-control study was conducted in Dembia district from October to November 2016. Out of the ten health centers in the district, four were randomly selected for the study in which 370 participants (185 cases and 185 controls) were enrolled. Data were collected using a pretested structured questionnaire. Factors associated with malaria infections were determined using logistic regression analysis. Odds ratio with 95% CI was used as a measure of association, and variables with a p-value of ≤0.05 were considered as statistically significant. The median age of all participants was 26 years, while that of cases and controls was 22 and 30 with a range of 1 to 80 and 2 to 71, respectively. In the multivariable logistic regression, over 15 years of age adjusted odds ratio(AOR) and confidence interval (CI) of (AOR = 18; 95% CI: 2.1, 161.5), being male (AOR = 2.2; 95% CI: 1.2, 3.9), outdoor activities at night (AOR = 5.7; 95% CI: 2.5, 12.7), bed net sharing (AOR = 3.9; 95% CI: 2.0, 7.7), and proximity to stagnant water sources (AOR = 2.7; 95% CI: 1.3, 5.4) were independent predictors. Being in over 15 years of age group, male gender, night time activity, bed net sharing and proximity to stagnant water sources were determinant factors of malaria infection in Dembia district. Additional interventions and strategies which focus on men, outdoor work at night, household net utilization, and nearby stagnant water sources are essential to reduce malaria infections in the area.
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Impact of Malaria at the End of Pregnancy on Infant Mortality and Morbidity
Sigauque, Betuel; Sanz, Sergi; Maixenchs, María; Ordi, Jaume; Aponte, John J; Mabunda, Samuel; Alonso, Pedro L; Menéndez, Clara
2011-01-01
Background. There is some consensus that malaria in pregnancy may negatively affect infant's mortality and malaria morbidity, but there is less evidence concerning the factors involved. Methods. A total of 1030 Mozambican pregnant women were enrolled in a randomized, placebo-controlled trial of intermittent preventive treatment with sulfadoxine-pyrimethamine, and their infants were followed up throughout infancy. Overall mortality and malaria morbidity rates were recorded. The association of maternal and fetal risk factors with infant mortality and malaria morbidity was assessed. Results. There were 58 infant deaths among 997 live-born infants. The risk of dying during infancy was increased among infants born to women with acute placental infection (odds ratio [OR], 5.08 [95% confidence interval (CI), 1.77–14.53)], parasitemia in cord blood (OR, 19.31 [95% CI, 4.44–84.02]), low birth weight (OR, 2.82 [95% CI, 1.27–6.28]) or prematurity (OR, 3.19 [95% CI, 1.14–8.95]). Infants born to women who had clinical malaria during pregnancy (OR, 1.96 [95% CI, 1.13–3.41]) or acute placental infection (OR, 4.63 [95% CI, 2.10–10.24]) had an increased risk of clinical malaria during infancy. Conclusions. Malaria infection at the end of pregnancy and maternal clinical malaria negatively impact survival and malaria morbidity in infancy. Effective clinical management and prevention of malaria in pregnancy may improve infant's health and survival. PMID:21199881
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Snow, Robert W; Okiro, Emelda A; Gething, Peter W; Atun, Rifat; Hay, Simon I
2010-10-23
Financing for malaria control has increased as part of international commitments to achieve the Millennium Development Goals (MDGs). We aimed to identify the unmet financial needs that would be biologically and economically equitable and would increase the chances of reaching worldwide malaria-control ambitions. Populations at risk of stable Plasmodium falciparum or Plasmodium vivax transmission were calculated for 2007 and 2009 for 93 malaria-endemic countries to measure biological need. National per-person gross domestic product (GDP) was used to define economic need. An analysis of external donor assistance for malaria control was done for the period 2002-09 to compute overall and annualised per-person at-risk-funding commitments. Annualised malaria donor assistance was compared with independent predictions of funding needed to reach international targets of 80% coverage of best practices in case-management and effective disease prevention. Countries were ranked in relation to biological, economic, and unmet needs to examine equity and adequacy of support by 2010. International financing for malaria control has increased by 166% (from $0·73 billion to $1·94 billion) since 2007 and is broadly consistent with biological needs. African countries have become major recipients of external assistance; however, countries where P vivax continues to pose threats to control ambitions are not as well funded. 21 countries have reached adequate assistance to provide a comprehensive suite of interventions by 2009, including 12 countries in Africa. However, this assistance was inadequate for 50 countries representing 61% of the worldwide population at risk of malaria-including ten countries in Africa and five in Asia that coincidentally are some of the poorest countries. Approval of donor funding for malaria control does not correlate with GDP. Funding for malaria control worldwide is 60% lower than the US$4·9 billion needed for comprehensive control in 2010; this includes
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Shafique, Muhammad; Edwards, Hannah M; De Beyl, Celine Zegers; Thavrin, Bou Kheng; Min, Myo; Roca-Feltrer, Arantxa
2016-02-16
Positive deviance (PD) is an asset-based, community-driven approach to behaviour change that has successfully been applied to address many health and social problems. It is yet to have been assessed for malaria control but may represent a promising tool for malaria elimination given its suitability in targeting small and remote population groups, apparent sustainability and ability to instil a high amount of community mobilisation. Here, the PD methodology as applied to malaria is explained, with focus upon and qualitative assessment of a proof of concept study in Cambodia. Three villages in Battambang, northwestern Cambodia were selected for the intervention, with an estimated population of 5036 including both residents and migrant workers. In August 2010, field teams conducted a 1 week PD process to sensitise and mobilise the community, establish normative behaviours in relation to malaria control and prevention, identify positive deviant behaviours from within the community, and identify PD volunteers. Until March 2011, PD volunteers were supported by field teams via monthly meetings to conduct activities in their respective communities to increase practice of PD behaviours. In February 2012, 1 year following the end of external support, evaluative interviews were conducted with community members to qualitatively assess community acceptance and interpretation of the PD intervention, perceived behaviour changes, and perceived positive outcomes. Qualitative data from focus group discussions and in-depth interviews showed that the PD approach was well-accepted into the communities and created a strong sense of community empowerment. Positive behaviour change was linked to the PD intervention, including greater usage of nets by forest goers, and use of public health facilities for malaria diagnosis and treatment. One year following the end of external assistance, PD volunteers were still conducting activities in their respective communities. PD offers a promising
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NASA Astrophysics Data System (ADS)
Gianotti, Rebecca L.; Bomblies, Arne; Eltahir, Elfatih A. B.
2009-08-01
This paper describes the first use of Hydrology-Entomology and Malaria Transmission Simulator (HYDREMATS), a physically based distributed hydrology model, to investigate environmental management methods for malaria vector control in the Sahelian village of Banizoumbou, Niger. The investigation showed that leveling of topographic depressions where temporary breeding habitats form during the rainy season, by altering pool basin microtopography, could reduce the pool persistence time to less than the time needed for establishment of mosquito breeding, approximately 7 days. Undertaking soil surface plowing can also reduce pool persistence time by increasing the infiltration rate through an existing pool basin. Reduction of the pool persistence time to less than the rainfall interstorm period increases the frequency of pool drying events, removing habitat for subadult mosquitoes. Both management approaches could potentially be considered within a given context. This investigation demonstrates that management methods that modify the hydrologic environment have significant potential to contribute to malaria vector control in water-limited, Sahelian Africa.
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Community perceptions of a malaria vaccine in the Kintampo districts of Ghana
2013-01-01
Background Malaria remains the leading cause of morbidity and mortality in sub-Saharan Africa despite tools currently available for its control. Making malaria vaccine available for routine use will be a major hallmark, but its acceptance by community members and health professionals within the health system could pose considerable challenge as has been found with the introduction of polio vaccinations in parts of West Africa. Some of these challenges may not be expected since decisions people make are many a time driven by a complex myriad of perceptions. This paper reports knowledge and perceptions of community members in the Kintampo area of Ghana where malaria vaccine trials have been ongoing as part of the drive for the first-ever licensed malaria vaccine in the near future. Methods Both qualitative and quantitative methods were used in the data collection processes. Women and men whose children were or were not involved in the malaria vaccine trial were invited to participate in focus group discussions (FGDs). Respondents, made up of heads of religious groupings in the study area, health care providers, traditional healers and traditional birth attendants, were also invited to participate in in-depth interviews (IDIs). A cross-sectional survey was conducted in communities where the malaria vaccine trial (Mal 047RTS,S) was carried out. In total, 12 FGDs, 15 IDIs and 466 household head interviews were conducted. Results Knowledge about vaccines was widespread among participants. Respondents would like their children to be vaccinated against all childhood illnesses including malaria. Knowledge of the long existing routine vaccines was relatively high among respondents compared to hepatitis B and Haemophilus influenza type B vaccines that were introduced more recently in 2002. There was no clear religious belief or sociocultural practice that will serve as a possible barrier to the acceptance of a malaria vaccine. Conclusion With the assumption that a malaria
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Optimal control in a model of malaria with differential susceptibility
NASA Astrophysics Data System (ADS)
Hincapié, Doracelly; Ospina, Juan
2014-06-01
A malaria model with differential susceptibility is analyzed using the optimal control technique. In the model the human population is classified as susceptible, infected and recovered. Susceptibility is assumed dependent on genetic, physiological, or social characteristics that vary between individuals. The model is described by a system of differential equations that relate the human and vector populations, so that the infection is transmitted to humans by vectors, and the infection is transmitted to vectors by humans. The model considered is analyzed using the optimal control method when the control consists in using of insecticide-treated nets and educational campaigns; and the optimality criterion is to minimize the number of infected humans, while keeping the cost as low as is possible. One first goal is to determine the effects of differential susceptibility in the proposed control mechanism; and the second goal is to determine the algebraic form of the basic reproductive number of the model. All computations are performed using computer algebra, specifically Maple. It is claimed that the analytical results obtained are important for the design and implementation of control measures for malaria. It is suggested some future investigations such as the application of the method to other vector-borne diseases such as dengue or yellow fever; and also it is suggested the possible application of free software of computer algebra like Maxima.
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Malaria diagnostic capacity in health facilities in Ethiopia
2014-01-01
Background Accurate early diagnosis and prompt treatment is one of the key strategies to control and prevent malaria in Ethiopia where both Plasmodium falciparum and Plasmodium vivax are sympatric and require different treatment regimens. Microscopy is the standard for malaria diagnosis at the health centres and hospitals whereas rapid diagnostic tests are used at community-level health posts. The current study was designed to assess malaria microscopy capacity of health facilities in Oromia Regional State and Dire Dawa Administrative City, Ethiopia. Methods A descriptive cross-sectional study was conducted from February to April 2011 in 122 health facilities, where health professionals were interviewed using a pre-tested, standardized assessment tool and facilities’ laboratory practices were assessed by direct observation. Results Of the 122 assessed facilities, 104 (85%) were health centres and 18 (15%) were hospitals. Out of 94 health facilities reportedly performing blood films, only 34 (36%) used both thin and thick smears for malaria diagnosis. The quality of stained slides was graded in 66 health facilities as excellent, good and poor quality in 11(17%), 31 (47%) and 24 (36%) respectively. Quality assurance guidelines and malaria microscopy standard operating procedures were found in only 13 (11%) facilities and 12 (10%) had involved in external quality assessment activities, and 32 (26%) had supportive supervision within six months of the survey. Only seven (6%) facilities reported at least one staff’s participation in malaria microscopy refresher training during the previous 12 months. Although most facilities, 96 (79%), had binocular microscopes, only eight (7%) had the necessary reagents and supplies to perform malaria microscopy. Treatment guidelines for malaria were available in only 38 (31%) of the surveyed facilities. Febrile patients with negative malaria laboratory test results were managed with artemether-lumefantrine or chloroquine in 51% (53
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Seasonal vaccination against malaria: a potential use for an imperfect malaria vaccine.
Greenwood, Brian; Dicko, Alassane; Sagara, Issaka; Zongo, Issaka; Tinto, Halidou; Cairns, Matthew; Kuepfer, Irene; Milligan, Paul; Ouedraogo, Jean-Bosco; Doumbo, Ogobara; Chandramohan, Daniel
2017-05-02
In many parts of the African Sahel and sub-Sahel, where malaria remains a major cause of mortality and morbidity, transmission of the infection is highly seasonal. Seasonal malaria chemoprevention (SMC), which involves administration of a full course of malaria treatment to young children at monthly intervals during the high transmission season, is proving to be an effective malaria control measure in these areas. However, SMC does not provide complete protection and it is demanding to deliver for both families and healthcare givers. Furthermore, there is a risk of the emergence in the future of resistance to the drugs, sulfadoxine-pyrimethamine and amodiaquine, that are currently being used for SMC. Substantial progress has been made in the development of malaria vaccines during the past decade and one malaria vaccine, RTS,S/AS01, has received a positive opinion from the European Medicines Authority and will soon be deployed in large-scale, pilot implementation projects in sub-Saharan Africa. A characteristic feature of this vaccine, and potentially of some of the other malaria vaccines under development, is that they provide a high level of efficacy during the period immediately after vaccination, but that this wanes rapidly, perhaps because it is difficult to develop effective immunological memory to malaria antigens in subjects exposed previously to malaria infection. A potentially effective way of using malaria vaccines with high initial efficacy but which provide only a short period of protection could be annual, mass vaccination campaigns shortly before each malaria transmission season in areas where malaria transmission is confined largely to a few months of the year.
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Cost Effectiveness of Malaria Interventions from Preelimination through Elimination: a Study in Iran
Rezaei-Hemami, Mohsen; Akbari-Sari, Ali; Raiesi, Ahmad; Vatandoost, Hassan; Majdzadeh, Reza
2014-01-01
Background Malaria still is considered as a public health problem in Iran. The aim of the National Malaria Control Department is to reach the elimination by 2024. By decreasing the number of malaria cases in preelimination phase the cost effectiveness of malaria interventions decreases considerably. This study estimated the cost effectiveness of various strategies to combat malaria in preelimination and elimination phases in Iran. Methods: running costs of the interventions at each level of intervention was estimated by using evidence and expert opinions. The effect of each intervention was estimated using the documentary evidence available and expert opinions. Using a point estimate and distribution of each variable the sensitivity was evaluated with the Monte Carlo method. Results: The most cost-effective interventions were insecticide treated net (ITN), larviciding, surveillance for diagnosis and treatment of patients less than 24 hours, and indoor residual spraying (IRS) respectively, No related evidence found for the effectiveness of the border facilities. Conclusion: This study showed that interventions in the elimination phase of malaria have low cost effectiveness in Iran like many other countries. However ITN is the most cost effective intervention among the available interventions. PMID:25629064
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Malaria eradication: the economic, financial and institutional challenge.
Mills, Anne; Lubell, Yoel; Hanson, Kara
2008-12-11
Malaria eradication raises many economic, financial and institutional challenges. This paper reviews these challenges, drawing on evidence from previous efforts to eradicate malaria, with a special focus on resource-poor settings; summarizes more recent evidence on the challenges, drawing on the literature on the difficulties of scaling-up malaria control and strengthening health systems more broadly; and explores the implications of these bodies of evidence for the current call for elimination and intensified control. Economic analyses dating from the eradication era, and more recent analyses, suggest that, in general, the benefits of malaria control outweigh the costs, though few studies have looked at the relative returns to eradication versus long-term control. Estimates of financial costs are scanty and difficult to compare. In the 1960s, the consolidation phase appeared to cost less than $1 per capita and, in 1988, was estimated to be $2.31 per capita (both in 2006 prices). More recent estimates for high coverage of control measures suggest a per capita cost of several dollars. Institutional challenges faced by malaria eradication included limits to the rule of law (a major problem where malaria was concentrated in border areas with movement of people associated with illegal activities), the existence and performance of local implementing structures, and political sustainability at national and global levels. Recent analyses of the constraints to scaling-up malaria control, together with the historical evidence, are used to discuss the economic, financial and institutional challenges that face the renewed call for eradication and intensified control. The paper concludes by identifying a research agenda covering: issues of the allocative efficiency of malaria eradication, especially using macro-economic modelling to estimate the benefits and costs of malaria eradication and intensified control, and studies of the links between malaria control and economic
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Malaria eradication: the economic, financial and institutional challenge
Mills, Anne; Lubell, Yoel; Hanson, Kara
2008-01-01
Malaria eradication raises many economic, financial and institutional challenges. This paper reviews these challenges, drawing on evidence from previous efforts to eradicate malaria, with a special focus on resource-poor settings; summarizes more recent evidence on the challenges, drawing on the literature on the difficulties of scaling-up malaria control and strengthening health systems more broadly; and explores the implications of these bodies of evidence for the current call for elimination and intensified control. Economic analyses dating from the eradication era, and more recent analyses, suggest that, in general, the benefits of malaria control outweigh the costs, though few studies have looked at the relative returns to eradication versus long-term control. Estimates of financial costs are scanty and difficult to compare. In the 1960s, the consolidation phase appeared to cost less than $1 per capita and, in 1988, was estimated to be $2.31 per capita (both in 2006 prices). More recent estimates for high coverage of control measures suggest a per capita cost of several dollars. Institutional challenges faced by malaria eradication included limits to the rule of law (a major problem where malaria was concentrated in border areas with movement of people associated with illegal activities), the existence and performance of local implementing structures, and political sustainability at national and global levels. Recent analyses of the constraints to scaling-up malaria control, together with the historical evidence, are used to discuss the economic, financial and institutional challenges that face the renewed call for eradication and intensified control. The paper concludes by identifying a research agenda covering: ∘ issues of the allocative efficiency of malaria eradication, especially using macro-economic modelling to estimate the benefits and costs of malaria eradication and intensified control, and studies of the links between malaria control and economic
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Uneke, C J
2008-06-01
Malaria and typhoid fever still remain diseases of major public health importance in the tropics. Individuals in areas endemic for both the diseases are at substantial risk of contracting both these diseases, either concurrently or an acute infection superimposed on a chronic one. The objective of this report was to systematically review scientific data from studies conducted in the tropics on concurrent malaria and typhoid fever within the last two decades (1987-2007), to highlight the diagnostic challenges and the public health implications. Using the MedLine Entrez-PubMed search, relevant publications were identified for the review via the key words Malaria and Typhoid fever, which yielded 287 entries as of January 2008. Most of the studies reviewed expressed concern that poor diagnosis continues to hinder effective control of concurrent malaria and typhoid fever in the tropics due to: non-specific clinical presentation of the diseases; high prevalence of asymptomatic infections; lack of resources and insufficient access to trained health care providers and facilities; and widespread practice of self-treatment for clinically suspected malaria or typhoid fever. There were considerably higher rates of concurrent malaria and typhoid fever by Widal test compared to the bacteriological culture technique. Although culture technique remains the gold standard in typhoid fever diagnosis, Widal test is still of significant diagnostic value provided judicious interpretation of the test is made against a background of pertinent information. Malaria could be controlled through interventions to minimize human-vector contact, while improved personal hygiene, targeted vaccination campaigns and intensive community health education could help to control typhoid fever in the tropics.
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Bhattarai, Achuyt; Ali, Abdullah S; Kachur, S. Patrick; Mårtensson, Andreas; Abbas, Ali K; Khatib, Rashid; Al-mafazy, Abdul-wahiyd; Ramsan, Mahdi; Rotllant, Guida; Gerstenmaier, Jan F; Molteni, Fabrizio; Abdulla, Salim; Montgomery, Scott M; Kaneko, Akira; Björkman, Anders
2007-01-01
Background The Roll Back Malaria strategy recommends a combination of interventions for malaria control. Zanzibar implemented artemisinin-based combination therapy (ACT) for uncomplicated malaria in late 2003 and long-lasting insecticidal nets (LLINs) from early 2006. ACT is provided free of charge to all malaria patients, while LLINs are distributed free to children under age 5 y (“under five”) and pregnant women. We investigated temporal trends in Plasmodium falciparum prevalence and malaria-related health parameters following the implementation of these two malaria control interventions in Zanzibar. Methods and Findings Cross-sectional clinical and parasitological surveys in children under the age of 14 y were conducted in North A District in May 2003, 2005, and 2006. Survey data were analyzed in a logistic regression model and adjusted for complex sampling design and potential confounders. Records from all 13 public health facilities in North A District were analyzed for malaria-related outpatient visits and admissions. Mortality and demographic data were obtained from District Commissioner's Office. P. falciparum prevalence decreased in children under five between 2003 and 2006; using 2003 as the reference year, odds ratios (ORs) and 95% confidence intervals (CIs) were, for 2005, 0.55 (0.28–1.08), and for 2006, 0.03 (0.00–0.27); p for trend < 0.001. Between 2002 and 2005 crude under-five, infant (under age 1 y), and child (aged 1–4 y) mortality decreased by 52%, 33%, and 71%, respectively. Similarly, malaria-related admissions, blood transfusions, and malaria-attributed mortality decreased significantly by 77%, 67% and 75%, respectively, between 2002 and 2005 in children under five. Climatic conditions favorable for malaria transmission persisted throughout the observational period. Conclusions Following deployment of ACT in Zanzibar 2003, malaria-associated morbidity and mortality decreased dramatically within two years. Additional distribution of
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Amadi, Jacinter A; Olago, Daniel O; Ong'amo, George O; Oriaso, Silas O; Nyamongo, Isaac K; Estambale, Benson B A
2018-05-09
The decline in global malaria cases is attributed to intensified utilization of primary vector control interventions and artemisinin-based combination therapies (ACTs). These strategies are inadequate in many rural areas, thus adopting locally appropriate integrated malaria control strategies is imperative in these heterogeneous settings. This study aimed at investigating trends and local knowledge on malaria and to develop a framework for malaria control for communities in Baringo, Kenya. Clinical malaria cases obtained from four health facilities in the riverine and lowland zones were used to analyse malaria trends for the 2005-2014 period. A mixed method approach integrating eight focus group discussions, 12 key informant interviews, 300 survey questionnaires and two stakeholders' consultative forums were used to assess local knowledge on malaria risk and develop a framework for malaria reduction. Malaria cases increased significantly during the 2005-2014 period (tau = 0.352; p < 0.001) in the riverine zone. March, April, May, June and October showed significant increases compared to other months. Misconceptions about the cause and mode of malaria transmission existed. Gender-segregated outdoor occupation such as social drinking, farm activities, herding, and circumcision events increased the risk of mosquito bites. A positive relationship occurred between education level and opinion on exposure to malaria risk after dusk (χ 2 = 2.70, p < 0.05). There was over-reliance on bed nets, yet only 68% (204/300) of respondents owned at least one net. Complementary malaria control measures were under-utilized, with 90% of respondents denying having used either sprays, repellents or burnt cow dung or plant leaves over the last one year before the study was conducted. Baraza, radios, and mobile phone messages were identified as effective media for malaria information exchange. Supplementary strategies identified included unblocking canals, clearing
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Spatial heterogeneity of malaria in Indian reserves of Southwestern Amazonia, Brazil
Souza-Santos, Reinaldo; de Oliveira, Maurício VG; Escobar, Ana Lúcia; Santos, Ricardo Ventura; Coimbra, Carlos EA
2008-01-01
Background Malaria constitutes a major cause of morbidity in the Brazilian Amazon where an estimated 6 million people are considered at high risk of transmission. Indigenous peoples in the Amazon are particularly vulnerable to potentially epidemic disease such as malaria; notwithstanding, very little is known about the epidemiology of malaria in Indian reservations of the region. The aim of this paper is to present a spatial analysis of malaria cases over a four-year time period (2003–2006) among indigenous peoples of the Brazilian State of Rondônia, southwestern Amazon, by using passive morbidity data (results from Giemsa-stained thick blood smears) gathered from the National Malaria Epidemiologic Surveillance System databank. Results A total of 4,160 cases of malaria were recorded in 14 Indian reserves in the State of Rondônia between 2003 and 2006. In six reservations no cases of malaria were reported in the period. Overall, P. vivax accounted for 76.18 of malaria cases reported in the indigenous population of Rondônia. The P. vivax/P. falciparum ratio for the period was 3.78. Two reserves accounted for over half of the cases reported for the total indigenous population in the period – Roosevelt and Pacaas Novas – with a total of 1,646 (39.57%) and 1,145 (27.52%) cases, respectively. Kernel mapping of malaria mean Annual Parasite Index – API according to indigenous reserves and environmental zones revealed a heterogeneous pattern of disease distribution, with one clear area of high risk of transmission comprising reservations of west Rondônia along the Guaporé-Madeira River basins, and another high risk area to the east, on the Roosevelt reserve. Conclusion By means of kernel mapping, it was shown that malaria risk varies widely between Indian reserves and environmental zones defined on the basis of predominant ecologic characteristics and land use patterns observed in the southwestern Brazilian Amazon. The geographical approach in this paper helped
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Alemu, Kassahun; Worku, Alemayehu; Berhane, Yemane; Kumie, Abera
2014-01-01
Background Information about malaria risk factors at high altitudes is scanty. Understanding the risk factors that determine the risk of malaria transmission at high altitude villages is important to facilitate implementing sustainable malaria control and prevention programs. Methods An unmatched case control study was conducted among patients seeking treatment at health centers in high altitude areas. Either microscopy or rapid diagnostic tests were used to confirm the presence of plasmodium species. A generalized linear model was used to identify the predictors of malaria transmission in high altitude villages. Results Males (AOR = 3.11, 95%CI: 2.28, 4.23), and those who traveled away from the home in the previous month (AOR = 2.01, 95% CI: 1.56, 2.58) were strongly associated with presence of malaria in high altitude villages. Other significant factors, including agriculture in occupation (AOR = 1.41, 95% CI: 1.05, 1.93), plants used for fencing (AOR = 1.70, 95% CI: 1.18, 2.52) and forests near the house (AOR = 1.60, 95% CI: 1.15, 2.47), were found predictors for malaria in high altitude villages. Conclusion Travel outside of their home was an important risk of malaria infections acquisition. Targeting males who frequently travel to malarious areas can reduce malaria transmission risks in high altitude areas. PMID:24748159
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Ippolito, Matthew M; Kamavu, Luc K; Kabuya, Jean-Bertin; Tente, Catherine; Chileshe, Edward; Wapachole, McBerth; Thuma, Philip E; Muleba, Mbanga; Chaponda, Mike; Mulenga, Modest; Moss, William J; For The Southern And Central Africa International Centers Of Excellence For Malaria Research
2018-04-23
Malaria remains a public health crisis in areas where it has resisted control efforts. In Nchelenge District, a high- transmission area in northern Zambia, malaria accounts for more than one-third of pediatric hospitalizations and nearly one-half of hospital deaths in children. To identify risk factors for death due to malaria, we conducted a retrospective, time-matched case-control study of 126 children hospitalized with malaria who died (cases) and 126 children who survived (controls). There were no differences in age, gender, hemoglobin concentration, or prevalence of severe anemia between cases and controls. Children who died were more likely to come from villages located at greater distances from the hospital than children who survived (median 13.5 versus 3.2 km). Each additional kilometer of distance from the hospital increased the odds of death by 4% (odds ratio 1.04, 95% confidence interval 1.01-1.07, P < 0.01). Extent of anemia and admission during periods when blood was unavailable for transfusion were associated with early death ( P ≤ 0.03). Delays in initiation of treatment of severe malaria contribute to the increased odds of death in children referred from more distant health centers, and might be mitigated by transportation improvements, capacity at rural health posts to administer treatment before transfer, hospital triage systems that minimize time to treatment, and reliable blood product stores at referral hospitals.
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Large-scale use of mosquito larval source management for malaria control in Africa: a cost analysis
2011-01-01
Background At present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) is being scaled up in Africa with substantial funding from donors. A third vector control method, larval source management (LSM), has been historically very successful and is today widely used for mosquito control globally, except in Africa. With increasing risk of insecticide resistance and a shift to more exophilic vectors, LSM is now under re-evaluation for use against afro-tropical vector species. Here the costs of this intervention were evaluated. Methods The 'ingredients approach' was used to estimate the economic and financial costs per person protected per year (pppy) for large-scale LSM using microbial larvicides in three ecologically diverse settings: (1) the coastal metropolitan area of Dar es Salaam in Tanzania, (2) a highly populated Kenyan highland area (Vihiga District), and (3) a lakeside setting in rural western Kenya (Mbita Division). Two scenarios were examined to investigate the cost implications of using alternative product formulations. Sensitivity analyses on product prices were carried out. Results The results show that for programmes using the same granular formulation larviciding costs the least pppy in Dar es Salaam (US$0.94), approximately 60% more in Vihiga District (US$1.50) and the most in Mbita Division (US$2.50). However, these costs are reduced substantially if an alternative water-dispensable formulation is used; in Vihiga, this would reduce costs to US$0.79 and, in Mbita Division, to US$1.94. Larvicide and staff salary costs each accounted for approximately a third of the total economic costs per year. The cost pppy depends mainly on: (1) the type of formulation required for treating different aquatic habitats, (2) the human population density relative to the density of aquatic habitats and (3) the potential to target the intervention in space and/or time. Conclusion Costs for LSM
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Njoroge, Margaret M; Tirados, Inaki; Lindsay, Steven W; Vale, Glyn A; Torr, Stephen J; Fillinger, Ulrike
2017-01-10
Malaria vector mosquitoes with exophilic and zoophilic tendencies, or with a high acceptance of alternative blood meal sources when preferred human blood-hosts are unavailable, may help maintain low but constant malaria transmission in areas where indoor vector control has been scaled up. This residual transmission might be addressed by targeting vectors outside the house. Here we investigated the potential of insecticide-treated cattle, as routinely used for control of tsetse and ticks in East Africa, for mosquito control. The malaria vector population in the study area was investigated weekly for 8 months using two different trapping tools: light traps indoors and cattle-baited traps (CBTs) outdoors. The effect of the application of the insecticide deltamethrin and the acaricide amitraz on cattle on host-seeking Anopheles arabiensis was tested experimentally in field-cages and the impact of deltamethrin-treated cattle explored under field conditions on mosquito densities on household level. CBTs collected on average 2.8 (95% CI: 1.8-4.2) primary [Anopheles gambiae (s.s.), An. arabiensis and An. funestus (s.s.)] and 6.3 (95% CI: 3.6-11.3) secondary malaria vectors [An. ivulorum and An. coustani (s.l.)] per trap night and revealed a distinct, complementary seasonality. At the same time on average only 1.4 (95% CI: 0.8-2.3) primary and 1.1 (95% CI: 0.6-2.0) secondary malaria vectors were collected per trap night with light traps indoors. Amitraz had no effect on survival of host-seeking An. arabiensis under experimental conditions but deltamethrin increased mosquito mortality (OR 19, 95% CI: 7-50), but only for 1 week. In the field, vector mortality in association with deltamethrin treatment was detected only with CBTs and only immediately after the treatment (OR 0.25, 95% CI: 0.13-0.52). Entomological sampling with CBTs highlights that targeting cattle for mosquito control has potential since it would not only target naturally zoophilic malaria vectors but also
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2010-01-01
Background Long-lasting insecticidal nets (LLINs) are an important tool for controlling malaria. Much attention has been devoted to determine both the effect of LLINs on the reduction of Plasmodium infection rate and on clinically-confirmed malaria cases in sub-Saharan Africa. We carried out an epidemiological study to investigate whether LLINs impact on Plasmodium prevalence rate and the proportion of clinically-confirmed malaria cases, in five villages in the district of Toumodi, central Côte d'Ivoire. Methods From April 2007 to November 2008, a community-based malaria control programme was implemented in the study villages, which involved large-scale distribution of LLINs, and training and sensitization activities within the community. We determined the effect of this programme on Plasmodium prevalence rate, clinically-confirmed malaria cases and proportion of high parasitaemia rates in children aged 6-59 months through a series of cross-sectional surveys starting in April 2007 and repeated once every 6 months. Results We observed a significant decrease in the mean P. falciparum prevalence rate from April 2007 to April 2008 (p = 0.029). An opposite trend was observed from November 2007 to November 2008 when P. falciparum prevalence rate increased significantly (p = 0.003). Highly significant decreases in the proportions of clinical malaria cases were observed between April 2007 and April 2008 (p < 0.001), and between November 2007 and November 2008 (p = 0.001). Conclusions Large-scale distribution of LLINs, accompanied by training and sensitization activities, significantly reduced Plasmodium prevalence rates among young children in the first year of the project, whereas overall clinical malaria rates dropped over the entire 18-month project period. A decrease in community motivation to sleep under bed nets, perhaps along with changing patterns of malaria transmission, might explain the observed increase in the Plasmodium prevalence rate between November 2007
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Smith, Jason; Tahani, Lloyd; Bobogare, Albino; Bugoro, Hugo; Otto, Francis; Fafale, George; Hiriasa, David; Kazazic, Adna; Beard, Grant; Amjadali, Amanda; Jeanne, Isabelle
2017-11-21
Malaria control remains a significant challenge in the Solomon Islands. Despite progress made by local malaria control agencies over the past decade, case rates remain high in some areas of the country. Studies from around the world have confirmed important links between climate and malaria transmission. This study focuses on understanding the links between malaria and climate in Guadalcanal, Solomon Islands, with a view towards developing a climate-based monitoring and early warning for periods of enhanced malaria transmission. Climate records were sourced from the Solomon Islands meteorological service (SIMS) and historical malaria case records were sourced from the National Vector-Borne Disease Control Programme (NVBDCP). A declining trend in malaria cases over the last decade associated with improved malaria control was adjusted for. A stepwise regression was performed between climate variables and climate-associated malaria transmission (CMT) at different lag intervals to determine where significant relationships existed. The suitability of these results for use in a three-tiered categorical warning system was then assessed using a Mann-Whitney U test. Of the climate variables considered, only rainfall had a consistently significant relationship with malaria in North Guadalcanal. Optimal lag intervals were determined for prediction using R 2 skill scores. A highly significant negative correlation (R = - 0.86, R 2 = 0.74, p < 0.05, n = 14) was found between October and December rainfall at Honiara and CMT in northern Guadalcanal for the subsequent January-June. This indicates that drier October-December periods are followed by higher malaria transmission periods in January-June. Cross-validation emphasized the suitability of this relationship for forecasting purposes [Formula: see text] as did Mann-Whitney U test results showing that rainfall below or above specific thresholds was significantly associated with above or below normal malaria
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Chuang, Ting-Wu; Soble, Adam; Ntshalintshali, Nyasatu; Mkhonta, Nomcebo; Seyama, Eric; Mthethwa, Steven; Pindolia, Deepa; Kunene, Simon
2017-06-01
Swaziland aims to eliminate malaria by 2020. However, imported cases from neighbouring endemic countries continue to sustain local parasite reservoirs and initiate transmission. As certain weather and climatic conditions may trigger or intensify malaria outbreaks, identification of areas prone to these conditions may aid decision-makers in deploying targeted malaria interventions more effectively. Malaria case-surveillance data for Swaziland were provided by Swaziland's National Malaria Control Programme. Climate data were derived from local weather stations and remote sensing images. Climate parameters and malaria cases between 2001 and 2015 were then analysed using seasonal autoregressive integrated moving average models and distributed lag non-linear models (DLNM). The incidence of malaria in Swaziland increased between 2005 and 2010, especially in the Lubombo and Hhohho regions. A time-series analysis indicated that warmer temperatures and higher precipitation in the Lubombo and Hhohho administrative regions are conducive to malaria transmission. DLNM showed that the risk of malaria increased in Lubombo when the maximum temperature was above 30 °C or monthly precipitation was above 5 in. In Hhohho, the minimum temperature remaining above 15 °C or precipitation being greater than 10 in. might be associated with malaria transmission. This study provides a preliminary assessment of the impact of short-term climate variations on malaria transmission in Swaziland. The geographic separation of imported and locally acquired malaria, as well as population behaviour, highlight the varying modes of transmission, part of which may be relevant to climate conditions. Thus, the impact of changing climate conditions should be noted as Swaziland moves toward malaria elimination.
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Ogoma, Sheila B.; Lweitoijera, Dickson W.; Ngonyani, Hassan; Furer, Benjamin; Russell, Tanya L.; Mukabana, Wolfgang R.; Killeen, Gerry F.; Moore, Sarah J.
2010-01-01
Background Partial mosquito-proofing of houses with screens and ceilings has the potential to reduce indoor densities of malaria mosquitoes. We wish to measure whether it will also reduce indoor densities of vectors of neglected tropical diseases. Methodology The main house entry points preferred by anopheline and culicine vectors were determined through controlled experiments using specially designed experimental huts and village houses in Lupiro village, southern Tanzania. The benefit of screening different entry points (eaves, windows and doors) using PVC-coated fibre glass netting material in terms of reduced indoor densities of mosquitoes was evaluated compared to the control. Findings 23,027 mosquitoes were caught with CDC light traps; 77.9% (17,929) were Anopheles gambiae sensu lato, of which 66.2% were An. arabiensis and 33.8% An. gambiae sensu stricto. The remainder comprised 0.2% (50) An. funestus, 10.2% (2359) Culex spp. and 11.6% (2664) Mansonia spp. Screening eaves reduced densities of Anopheles gambiae s. l. (Relative ratio (RR) = 0.91; 95% CI = 0.84, 0.98; P = 0.01); Mansonia africana (RR = 0.43; 95% CI = 0.26, 0.76; P<0.001) and Mansonia uniformis (RR = 0.37; 95% CI = 0.25, 0.56; P<0.001) but not Culex quinquefasciatus, Cx. univittatus or Cx. theileri. Numbers of these species were reduced by screening windows and doors but this was not significant. Significance This study confirms that across Africa, screening eaves protects households against important mosquito vectors of filariasis, Rift Valley Fever and O'Nyong nyong as well as malaria. While full house screening is required to exclude Culex species mosquitoes, screening of eaves alone or fitting ceilings has considerable potential for integrated control of other vectors of filariasis, arbovirus and malaria. PMID:20689815
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Brown, Zachary S.; Dickinson, Katherine L.; Kramer, Randall A.
2014-01-01
The evolutionary dynamics of insecticide resistance in harmful arthropods has economic implications, not only for the control of agricultural pests (as has been well studied), but also for the control of disease vectors, such as malaria-transmitting Anopheles mosquitoes. Previous economic work on insecticide resistance illustrates the policy relevance of knowing whether insecticide resistance mutations involve fitness costs. Using a theoretical model, this article investigates economically optimal strategies for controlling malaria-transmitting mosquitoes when there is the potential for mosquitoes to evolve resistance to insecticides. Consistent with previous literature, we find that fitness costs are a key element in the computation of economically optimal resistance management strategies. Additionally, our models indicate that different biological mechanisms underlying these fitness costs (e.g., increased adult mortality and/or decreased fecundity) can significantly alter economically optimal resistance management strategies. PMID:23448053
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Smith, Jennifer L; Auala, Joyce; Haindongo, Erastus; Uusiku, Petrina; Gosling, Roly; Kleinschmidt, Immo; Mumbengegwi, Davis; Sturrock, Hugh J W
2017-02-10
A key component of malaria elimination campaigns is the identification and targeting of high risk populations. To characterize high risk populations in north central Namibia, a prospective health facility-based case-control study was conducted from December 2012-July 2014. Cases (n = 107) were all patients presenting to any of the 46 health clinics located in the study districts with a confirmed Plasmodium infection by multi-species rapid diagnostic test (RDT). Population controls (n = 679) for each district were RDT negative individuals residing within a household that was randomly selected from a census listing using a two-stage sampling procedure. Demographic, travel, socio-economic, behavioural, climate and vegetation data were also collected. Spatial patterns of malaria risk were analysed. Multivariate logistic regression was used to identify risk factors for malaria. Malaria risk was observed to cluster along the border with Angola, and travel patterns among cases were comparatively restricted to northern Namibia and Angola. Travel to Angola was associated with excessive risk of malaria in males (OR 43.58 95% CI 2.12-896), but there was no corresponding risk associated with travel by females. This is the first study to reveal that gender can modify the effect of travel on risk of malaria. Amongst non-travellers, male gender was also associated with a higher risk of malaria compared with females (OR 1.95 95% CI 1.25-3.04). Other strong risk factors were sleeping away from the household the previous night, lower socioeconomic status, living in an area with moderate vegetation around their house, experiencing moderate rainfall in the month prior to diagnosis and living <15 km from the Angolan border. These findings highlight the critical need to target malaria interventions to young male travellers, who have a disproportionate risk of malaria in northern Namibia, to coordinate cross-border regional malaria prevention initiatives and to scale up coverage of
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2012-01-01
Background The burden of malaria has decreased in parts of Africa following the scaling up of control interventions. However, similar data are limited from high transmission settings. Methods A cohort of 100 children, aged six weeks to 10 months of age, were enrolled in an area of high malaria transmission intensity and followed through 48 months of age. Children were given a long-lasting insecticide-treated bed net (LLIN) at enrolment and received all care, including monthly blood smears and treatment with artemisinin-based combination therapy (ACT) for uncomplicated malaria, at a dedicated clinic. The incidence of malaria was estimated by passive surveillance and associations between malaria incidence and age, calendar time and season were measured using generalized estimating equations. Results Reported compliance with LLINs was 98% based on monthly routine evaluations. A total of 1,633 episodes of malaria were observed, with a median incidence of 5.3 per person-year (PPY). There were only six cases of complicated malaria, all single convulsions. Malaria incidence peaked at 6.5 PPY at 23 months of age before declining to 3.5 PPY at 48 months. After adjusting for age and season, the risk of malaria increased by 52% from 2008 to 2011 (RR 1.52, 95% CI 1.10-2.09). Asymptomatic parasitaemia was uncommon (monthly prevalence <10%) and rarely observed prior to 24 months of age. Conclusions In Tororo, despite provision of LLINs and prompt treatment with ACT, the incidence of malaria is very high and appears to be rising. Additional malaria control interventions in high transmission settings are likely needed. Trial registration Current Controlled Trials Identifier NCT00527800 PMID:23273022
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2013-01-01
Background Malaria rapid diagnostic tests (RDTs) are a useful tool in endemic malaria countries, where light microscopy is not feasible. In non-endemic countries they can be used as complementary tests to provide timely results in case of microscopy inexperience. This study aims to compare the new VIKIA Malaria Ag Pf/Pan™ RDT with PCR-corrected microscopy results and the commonly used CareStart™ RDT to diagnose falciparum and non-falciparum malaria in the endemic setting of Bamako, Mali and the non-endemic setting of Lyon, France. Methods Blood samples were collected during a 12-months and six-months period in 2011 from patients suspected to have malaria in Lyon and Bamako respectively. The samples were examined by light microscopy, the VIKIA Malaria Ag Pf/Pan™ test and in Bamako additionally with the CareStart™ RDT. Discordant results were corrected by real-time PCR. Sensitivity, specificity, positive predictive value and negative predictive value were used to evaluate test performance. Results Samples of 877 patients from both sites were included. The VIKIA Malaria Ag Pf/Pan™ had a sensitivity of 98% and 96% for Plasmodium falciparum in Lyon and Bamako, respectively, performing similar to PCR-corrected microscopy. Conclusions The VIKIA Malaria Ag Pf/Pan™ performs similar to PCR-corrected microscopy for the detection of P. falciparum, making it a valuable tool in malaria endemic and non-endemic regions. PMID:23742633
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2014-01-01
Background Rapid diagnostic tests (RDTs) are the current complement to microscopy for ensuring prompt malaria treatment. We determined the performance of three candidate RDTs (Paracheck™-Pf, SD Bioline malaria Ag-Pf and SD Bioline malaria Ag-Pf/pan) for rapid diagnosis of malaria in the Central African Republic. Methods Blood samples from consecutive febrile patients who attended for laboratory analysis of malaria at the three main health centres of Bangui were screened by microscopy and the RDTs. Two reference standards were used to assess the performance of the RDTs: microscopy and, a combination of microscopy plus nested PCR for slides reported as negative, on the assumption that negative results by microscopy were due to sub-patent parasitaemia. Results We analysed 436 samples. Using the combined reference standard of microscopy + PCR, the sensitivity of Paracheck™-Pf was 85.7% (95% CI, 80.8–89.8%), that of SD Bioline Ag-Pf was 85.4% (95% CI, 80.5–90.7%), and that of SD Bioline Ag-Pf/pan was 88.2% (95% CI, 83.2–92.0%). The tests performed less well in cases of low parasitaemia; however, the sensitivity was > 95% at > 500 parasites/μl. Conclusions Overall, SD Bioline malaria Ag-Pf and SD Bioline malaria Ag-Pf/pan performed slightly better than Paracheck™-Pf. Use of RDTs with reinforced microscopy practice and laboratory quality assurance should improve malaria treatment in the Central African Republic. PMID:24568311
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2011-01-01
Background About 90% of all malaria deaths in sub-Saharan Africa occur in children under five years. Fast and reliable diagnosis of malaria requires confirmation of the presence of malaria parasites in the blood of patients with fever or history suggestive of malaria; hence a prompt and accurate diagnosis of malaria is the key to effective disease management. Confirmation of malaria infection requires the availability of a rapid, sensitive, and specific testing at an affordable cost. We compared two recent methods (the novel Partec Rapid Malaria Test® (PT) and the Binax Now® Malaria Rapid Diagnostic Test (BN RDT) with the conventional Giemsa stain microscopy (GM) for the diagnosis of malaria among children in a clinical laboratory of a hospital in a rural endemic area of Ghana. Methods Blood samples were collected from 263 children admitted with fever or a history of fever to the pediatric clinic of the Agogo Presbyterian Hospital. The three different test methods PT, BN RDT and GM were performed independently by well trained and competent laboratory staff to assess the presence of malaria parasites. Results were analyzed and compared using GM as the reference standard. Results In 107 (40.7%) of 263 study participants, Plasmodium sp. was detected by GM. PT and BN RDT showed positive results in 111 (42.2%) and 114 (43.4%), respectively. Compared to GM reference standard, the sensitivities of the PT and BN RDT were 100% (95% CI: 96.6-100) and 97.2% (95% CI: 92.0-99.4), respectively, specificities were 97.4% (95% CI: 93.6-99.3) and 93.6% (95% CI: 88.5-96.9), respectively. There was a strong agreement (kappa) between the applied test methods (GM vs PT: 0.97; p < 0.001 and GM vs BN RDT: 0.90; p < 0.001). The average turnaround time per tests was 17 minutes. Conclusion In this study two rapid malaria tests, PT and BN RDT, demonstrated a good quality of their performance compared to conventional GM. Both methods require little training, have short turnaround times, are
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Ashley, Elizabeth A; Pyae Phyo, Aung; Woodrow, Charles J
2018-04-21
Following unsuccessful eradication attempts there was a resurgence of malaria towards the end of the 20th century. Renewed control efforts using a range of improved tools, such as long-lasting insecticide-treated bednets and artemisinin-based combination therapies, have more than halved the global burden of disease, but it remains high with 445 000 deaths and more than 200 million cases in 2016. Pitfalls in individual patient management are delayed diagnosis and overzealous fluid resuscitation in severe malaria. Even in the absence of drug resistance, parasite recurrence can occur, owing to high parasite densities, low host immunity, or suboptimal drug concentrations. Malaria elimination is firmly back as a mainstream policy but resistance to the artemisinin derivatives, their partner drugs, and insecticides present major challenges. Vaccine development continues on several fronts but none of the candidates developed to date have been shown to provide long-lasting benefits at a population level. Increased resources and unprecedented levels of regional cooperation and societal commitment will be needed if further substantial inroads into the malaria burden are to be made. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Ocampo, Denise; Booth, Mark
2016-07-22
Current interventions against malaria have significantly reduced the number of people infected and the number of deaths. Concerns about emerging resistance of both mosquitoes and parasites to intervention have been raised, and questions remain about how best to generate wider knowledge of the underlying evolutionary processes. The pedagogical and research principles of evolutionary medicine may provide an answer to this problem. Eight programme managers and five academic researchers were interviewed by telephone or videoconference to elicit their first-hand views and experiences of malaria control given that evolution is a constant threat to sustainable control. Interviewees were asked about their views on the relationship between practit groups and academics and for their thoughts on whether or not evolutionary medicine may provide a solution to reported tensions. There was broad agreement that evolution of both parasites and vectors presents an obstacle to sustainable control. It was also widely agreed that through more efficient monitoring, evolution could be widely monitored. Interviewees also expressed the view that even well planned interventions may fail if the evolutionary biology of the disease is not considered, potentially making current tools redundant. This scoping study suggests that it is important to make research, including evolutionary principles, available and easily applicable for programme managers and key decision-makers, including donors and politicians. The main conclusion is that sharing knowledge through the educational and research processes embedded within evolutionary medicine has potential to relieve tensions and facilitate sustainable control of malaria and other parasitic infections.
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Malaria Situation and Anopheline Mosquitoes in Qom Province, Central Iran
Farzinnia, B; Saghafipour, A; Abai, MR
2010-01-01
Background: The aims of this study was to analysis the current situation of malaria and to find the distribution of anopheline mosquitoes, as probable vectors of the disease, in Qom Province, central Iran. Methods: This study was carried out in two parts. First stage was data collection about malaria cases using recorded documents of patients in the Province health center, during 2001–2008. The second stage was entomological survey conducted by mosquito larval collection method in 4 villages with different geographical positions in 2008. Data were analyzed using Excel software. Results: Of 4456 blood slides, 10.9% out were positive. Most of cases were imported from other countries (90.4%), mainly from Afghanistan (56.5%) and Pakistan (16.3%). Slide positive rate showed a maximum of 16.9% and a minimum of 2.9% in 2008 and 2007, respectively. Plasmodium vivax was causative agent of 93.75% of cases, followed by P. falciparum (6.25%). More than 15 years old age group contained the most malaria reported cases (66.7%). Two Anopheles species, An. superpictus and An. claviger were collected and identified. This is the first report of Anopheles claviger in Qom Province. Conclusion: Malaria is in the control stage in Qom Province. The rate of local transmission is very low (only 1 case), shows Anopheles superpictus, as the main malaria vector of central part of Iran, can play its role in malaria transmission in the area. PMID:22808402
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A weather-driven model of malaria transmission
Hoshen, Moshe B; Morse, Andrew P
2004-01-01
Background Climate is a major driving force behind malaria transmission and climate data are often used to account for the spatial, seasonal and interannual variation in malaria transmission. Methods This paper describes a mathematical-biological model of the parasite dynamics, comprising both the weather-dependent within-vector stages and the weather-independent within-host stages. Results Numerical evaluations of the model in both time and space show that it qualitatively reconstructs the prevalence of infection. Conclusion A process-based modelling structure has been developed that may be suitable for the simulation of malaria forecasts based on seasonal weather forecasts. PMID:15350206
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Kong, Xiangli; Liu, Xin; Tu, Hong; Xu, Yan; Niu, Jianbing; Wang, Yongbin; Zhao, Changlei; Kou, Jingxuan; Feng, Jun
2017-01-31
Shandong Province experienced a declining malaria trend of local-acquired transmission, but the increasing imported malaria remains a challenge. Therefore, understanding the epidemiological characteristics of malaria and the control and elimination strategy and interventions is needed for better planning to achieve the overall elimination goal in Shandong Province. A retrospective study was conducted and all individual cases from a web-based reporting system were reviewed and analysed to explore malaria-endemic characteristics in Shandong from 2005 to 2015. Annual malaria incidence reported in 2005-2015 were geo-coded and matched to the county-level. Spatial cluster analysis was performed to evaluate any identified spatial disease clusters for statistical significance. The space-time cluster was detected with high rates through the retrospective space-time analysis scanning using the discrete Poisson model. The overall malaria incidence decreased to a low level during 2005-2015. In total, 1564 confirmed malaria cases were reported, 27.1% of which (n = 424) were indigenous cases. Most of the indigenous case (n = 339, 80.0%) occurred from June to October. However, the number and scale of imported cases have been increased but no significant difference was observed during months. Shandong is endemic for both Plasmodium vivax (n = 730) and Plasmodium falciparum (n = 674). The disease is mainly distributed in Southern (n = 710) and Eastern region (n = 424) of Shandong, such as Jinning (n = 214 [13.7%]), Weihai (n = 151 [9.7%]), and Yantai (n = 107 [6.8%]). Furthermore, the spatial cluster analysis of malaria cases from 2005 to 2015 indicated that the diseased was not randomly distributed. For indigenous cases, a total of 15 and 2 high-risk counties were determined from 2005 to 2009 (control phase) and from 2010 to 2015 (elimination phase), respectively. For imported cases, a total of 26 and 29 high-risk counties were determined from 2005 to 2009
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Ferguson, Heather M; Ng'habi, Kija R; Walder, Thomas; Kadungula, Demetrius; Moore, Sarah J; Lyimo, Issa; Russell, Tanya L; Urassa, Honorathy; Mshinda, Hassan; Killeen, Gerry F; Knols, Bart GJ
2008-01-01
Background Medical entomologists increasingly recognize that the ability to make inferences between laboratory experiments of vector biology and epidemiological trends observed in the field is hindered by a conceptual and methodological gap occurring between these approaches which prevents hypothesis-driven empirical research from being conducted on relatively large and environmentally realistic scales. The development of Semi-Field Systems (SFS) has been proposed as the best mechanism for bridging this gap. Semi-field systems are defined as enclosed environments, ideally situated within the natural ecosystem of a target disease vector and exposed to ambient environmental conditions, in which all features necessary for its life cycle completion are present. Although the value of SFS as a research tool for malaria vector biology is gaining recognition, only a few such facilities exist worldwide and are relatively small in size (< 100 m2). Methods The establishment of a 625 m2 state-of-the-art SFS for large-scale experimentation on anopheline mosquito ecology and control within a rural area of southern Tanzania, where malaria transmission intensities are amongst the highest ever recorded, is described. Results A greenhouse frame with walls of mosquito netting and a polyethylene roof was mounted on a raised concrete platform at the Ifakara Health Institute. The interior of the SFS was divided into four separate work areas that have been set up for a variety of research activities including mass-rearing for African malaria vectors under natural conditions, high throughput evaluation of novel mosquito control and trapping techniques, short-term assays of host-seeking behaviour and olfaction, and longer-term experimental investigation of anopheline population dynamics and gene flow within a contained environment that simulates a local village domestic setting. Conclusion The SFS at Ifakara was completed and ready for use in under two years. Preliminary observations
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Urbanization and the global malaria recession.
Tatem, Andrew J; Gething, Peter W; Smith, David L; Hay, Simon I
2013-04-17
The past century has seen a significant contraction in the global extent of malaria transmission, resulting in over 50 countries being declared malaria free, and many regions of currently endemic countries eliminating the disease. Moreover, substantial reductions in transmission have been seen since 1900 in those areas that remain endemic today. Recent work showed that this malaria recession was unlikely to have been driven by climatic factors, and that control measures likely played a significant role. It has long been considered, however, that economic development, and particularly urbanization, has also been a causal factor. The urbanization process results in profound socio-economic and landscape changes that reduce malaria transmission, but the magnitude and extent of these effects on global endemicity reductions are poorly understood. Global data at subnational spatial resolution on changes in malaria transmission intensity and urbanization trends over the past century were combined to examine the relationships seen over a range of spatial and temporal scales. A consistent pattern of increased urbanization coincident with decreasing malaria transmission and elimination over the past century was found. Whilst it remains challenging to untangle whether this increased urbanization resulted in decreased transmission, or that malaria reductions promoted development, the results point to a close relationship between the two, irrespective of national wealth. The continuing rapid urbanization in malaria-endemic regions suggests that such malaria declines are likely to continue, particularly catalyzed by increasing levels of direct malaria control.
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Elimination of Plasmodium vivax Malaria in Azerbaijan
Mammadov, Suleyman; Gasimov, Elkhan; Kurdova-Mintcheva, Rossitza; Wongsrichanalai, Chansuda
2016-01-01
Azerbaijan in the south caucasus region of far southeastern Europe has a long history of malaria endemicity but just successfully eliminated local transmission. After a period of relatively stable malaria situation (1960–1970), the country witnessed an epidemic followed by a series of outbreaks of various magnitudes in the following two decades, all caused by Plasmodium vivax. Compared with 1993, the number of malaria cases in the country jumped 29 times in 1994, 123 times in 1995, and 571 times in 1996 at the peak of the epidemic, when 13,135 cases were officially registered. Incidence rate increased dramatically from 0.2/100,000 population in 1991 to over 17/100,000 population in 1996. Scaled-up malaria control led to the containment of the epidemic and to a dramatic decrease of malaria burden nationwide. Azerbaijan has applied contemporary, complex control and surveillance strategies and approaches and is currently in the prevention of reintroduction phase. This article describes Azerbaijan's public health experience in conducting malaria control and elimination interventions over several decades until 2013 when the country reached an important milestone—no indigenous malaria cases were recorded. PMID:27708184
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Quantifying the economic burden of malaria in Nigeria using the willingness to pay approach
Jimoh, Ayodele; Sofola, Oluyemi; Petu, Amos; Okorosobo, Tuoyo
2007-01-01
Background Malaria illness imposes great burden on the society as it has adverse effects on the physical, mental and social well being of the people as well as on the economic development of the nation. Methods The study uses the Willingness To Pay (WTP) approach to evaluate the burden of malaria in Nigeria. Results The results indicate that households would be prepared to pay an average of about Naira 1,112 (USD 9.3) per month for the treatment of malaria. This is about Naira 427 (USD 3.6) in excess of the average expenditure they currently make on malaria treatment per month. Similarly, households are willing to pay on the average a sum of Naira 7,324 (USD 61) per month for the control of malaria. Again, this is an excess of about Naira 2,715 (USD 22.6) over the cost they currently bear (protection, treatment and indirect costs), and it represents households' average valuation of their intangible costs of malaria illness. This amount represents about Naira 611.7 (USD 5.1) per head per month and Naira 7,340 (USD 61.2) per year. For a country with a population of about 120 million this translates to about Naira 880,801 million per annum representing about 12.0 per cent of Gross Domestic Product. Hence, the malaria burden in Nigeria is enormous and has a devastating impact on economic growth. Conclusion In the long term, it is important to recognize that health and poverty are closely linked. Reducing the burden of malaria in Nigeria will help to contribute to the economic well-being of communities; and poverty-reduction will be an essential input into improving health. National malaria control programme in Nigeria and their partners need to recognize these links, and identify mechanisms for ensuring that the poorest have access to essential health interventions. PMID:17517146
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Plasmodium falciparum Malaria Endemicity in Indonesia in 2010
Elyazar, Iqbal R. F.; Gething, Peter W.; Patil, Anand P.; Rogayah, Hanifah; Kusriastuti, Rita; Wismarini, Desak M.; Tarmizi, Siti N.; Baird, J. Kevin; Hay, Simon I.
2011-01-01
Background Malaria control programs require a detailed understanding of the contemporary spatial distribution of infection risk to efficiently allocate resources. We used model based geostatistics (MBG) techniques to generate a contemporary map of Plasmodium falciparum malaria risk in Indonesia in 2010. Methods Plasmodium falciparum Annual Parasite Incidence (PfAPI) data (2006–2008) were used to map limits of P. falciparum transmission. A total of 2,581 community blood surveys of P. falciparum parasite rate (PfPR) were identified (1985–2009). After quality control, 2,516 were included into a national database of age-standardized 2–10 year old PfPR data (PfPR2–10) for endemicity mapping. A Bayesian MBG procedure was used to create a predicted surface of PfPR2–10 endemicity with uncertainty estimates. Population at risk estimates were derived with reference to a 2010 human population count surface. Results We estimate 132.8 million people in Indonesia, lived at risk of P. falciparum transmission in 2010. Of these, 70.3% inhabited areas of unstable transmission and 29.7% in stable transmission. Among those exposed to stable risk, the vast majority were at low risk (93.39%) with the reminder at intermediate (6.6%) and high risk (0.01%). More people in western Indonesia lived in unstable rather than stable transmission zones. In contrast, fewer people in eastern Indonesia lived in unstable versus stable transmission areas. Conclusion While further feasibility assessments will be required, the immediate prospects for sustained control are good across much of the archipelago and medium term plans to transition to the pre-elimination phase are not unrealistic for P. falciparum. Endemicity in areas of Papua will clearly present the greatest challenge. This P. falciparum endemicity map allows malaria control agencies and their partners to comprehensively assess the region-specific prospects for reaching pre-elimination, monitor and evaluate the effectiveness of
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Gyuse, Abraham N.; Etokidem, Aniekan J.
2010-01-01
ABSTRACT Background Malaria prevention and treatment constitute an unbearable economic burden to most African countries, especially south of the Sahara, where about 500 million cases occur annually. The problem of malaria among adolescents has largely been overshadowed by the huge burden of the disease among young children. Attention to malaria among adolescents has also been diverted by the huge burden of HIV/AIDS among adolescents. Some surveys reveal a lack of knowledge and many misconceptions about the transmission and treatment of malaria, which could adversely affect malaria control measures and antimalarial therapy. Such a knowledge gap could have an adverse effect on school children, who could be used as change agents and as role models for their siblings and peers in the malaria control strategy. Objectives To determine the malaria prevention practices of school adolescents in the coastal community of Calabar, Nigeria. Method This was a cross-sectional survey involving secondary schools in southern Calabar. Four hundred adolescents were randomly selected from the 4565 learners in 5 out of 17 secondary schools in southern Calabar, Cross River State, Nigeria. A self-administered, semi-structured questionnaire was administered to the respondents. Results Most respondents (77.5%) were aware that the vector transmits the malaria parasite through biting. Fewer respondents would prevent malaria attacks by clearing the vegetation in the peri-domestic environment (13.5%), filling up potholes (16.9%), opening up drainage (11%), using insecticide-treated nets (25.7%) or using antimalarial drugs (11.2%). Less than one-tenth (8%) would use various other methods such as not accepting unscreened blood, while only 11% obtained the information from their teachers. Conclusion The study identified knowledge gaps among school children. There is a need to empower teachers with information about the cause of malaria and prevention strategies.
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Ferede, Getachew; Worku, Abiyu; Getaneh, Alemtegna; Ahmed, Ali; Haile, Tarekegn; Abdu, Yenus; Tessema, Belay; Wondimeneh, Yitayih; Alemu, Abebe
2013-01-01
Background. Malaria is a major public health problem in Ethiopia where an estimated 68% of the population lives in malarious areas. Studying its prevalence is necessary to implement effective control measures. Therefore, the aim of this study was to determine seven-year slide positive rate of malaria. Methods. A retrospective study was conducted at Metema Hospital from September 2006 to August 2012. Seven-year malaria cases data had been collected from laboratory registration book. Results. A total of 55,833 patients were examined for malaria; of these, 9486 (17%) study subjects were positive for malaria. The predominant Plasmodium species detected was P. falciparum (8602) (90.7%) followed by P. vivax (852) (9%). A slide positive rate of malaria within the last seven years (2006-2012) was almost constant with slight fluctuation. The age groups of 5-14 years old were highly affected by malariainfection (1375) (20.1%), followed by 15-29 years old (3986) (18.5%). High slide positive rate of malaria occurred during spring (September-November), followed by summer (June-August). Conclusion. Slide positive rate of malaria was high in study area. Therefore, health planners and administrators should give intensive health education for the community.
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Regules, Jason A; Cicatelli, Susan B; Bennett, Jason W; Paolino, Kristopher M; Twomey, Patrick S; Moon, James E; Kathcart, April K; Hauns, Kevin D; Komisar, Jack L; Qabar, Aziz N; Davidson, Silas A; Dutta, Sheetij; Griffith, Matthew E; Magee, Charles D; Wojnarski, Mariusz; Livezey, Jeffrey R; Kress, Adrian T; Waterman, Paige E; Jongert, Erik; Wille-Reece, Ulrike; Volkmuth, Wayne; Emerling, Daniel; Robinson, William H; Lievens, Marc; Morelle, Danielle; Lee, Cynthia K; Yassin-Rajkumar, Bebi; Weltzin, Richard; Cohen, Joe; Paris, Robert M; Waters, Norman C; Birkett, Ashley J; Kaslow, David C; Ballou, W Ripley; Ockenhouse, Christian F; Vekemans, Johan
2016-09-01
Three full doses of RTS,S/AS01 malaria vaccine provides partial protection against controlled human malaria parasite infection (CHMI) and natural exposure. Immunization regimens, including a delayed fractional third dose, were assessed for potential increased protection against malaria and immunologic responses. In a phase 2a, controlled, open-label, study of healthy malaria-naive adults, 16 subjects vaccinated with a 0-, 1-, and 2-month full-dose regimen (012M) and 30 subjects who received a 0-, 1-, and 7-month regimen, including a fractional third dose (Fx017M), underwent CHMI 3 weeks after the last dose. Plasmablast heavy and light chain immunoglobulin messenger RNA sequencing and antibody avidity were evaluated. Protection against repeat CHMI was evaluated after 8 months. A total of 26 of 30 subjects in the Fx017M group (vaccine efficacy [VE], 86.7% [95% confidence interval [CI], 66.8%-94.6%]; P < .0001) and 10 of 16 in the 012M group (VE, 62.5% [95% CI, 29.4%-80.1%]; P = .0009) were protected against infection, and protection differed between schedules (P = .040, by the log rank test). The fractional dose boosting increased antibody somatic hypermutation and avidity and sustained high protection upon rechallenge. A delayed third fractional vaccine dose improved immunogenicity and protection against infection. Optimization of the RTS,S/AS01 immunization regimen may lead to improved approaches against malaria. NCT01857869. Published by Oxford University Press on behalf of the Infectious Diseases Society of America, 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
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Uyoga, Sophie; Ndila, Carolyne M; Macharia, Alex W; Nyutu, Gideon; Shah, Shivang; Peshu, Norbert; Clarke, Geraldine M; Kwiatkowski, Dominic P; Rockett, Kirk A; Williams, Thomas N
2015-01-01
Summary Background The global prevalence of X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency is thought to be a result of selection by malaria, but epidemiological studies have yielded confusing results. We investigated the relationships between G6PD deficiency and both malaria and non-malarial illnesses among children in Kenya. Methods We did this study in Kilifi County, Kenya, where the G6PD c.202T allele is the only significant cause of G6PD deficiency. We tested the associations between G6PD deficiency and severe and complicated Plasmodium falciparum malaria through a case-control study of 2220 case and 3940 control children. Cases were children aged younger than 14 years, who visited the high dependency ward of Kilifi County Hospital with severe malaria between March 1, 1998, and Feb 28, 2010. Controls were children aged between 3–12 months who were born within the same study area between August 2006, and September 2010. We assessed the association between G6PD deficiency and both uncomplicated malaria and other common diseases of childhood in a cohort study of 752 children aged younger than 10 years. Participants of this study were recruited from a representative sample of households within the Ngerenya and Chonyi areas of Kilifi County between Aug 1, 1998, and July 31, 2001. The primary outcome measure for the case-control study was the odds ratio for hospital admission with severe malaria (computed by logistic regression) while for the cohort study it was the incidence rate ratio for uncomplicated malaria and non-malaria illnesses (computed by Poisson regression), by G6PD deficiency category. Findings 2863 (73%) children in the control group versus 1643 (74%) in the case group had the G6PD normal genotype, 639 (16%) versus 306 (14%) were girls heterozygous for G6PD c.202T, and 438 (11%) versus 271 (12%) children were either homozygous girls or hemizygous boys. Compared with boys and girls without G6PD deficiency, we found significant
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Lennon, Shirley Evelyn; Miranda, Adolfo; Henao, Juliana; Vallejo, Andres F; Perez, Julianh; Alvarez, Alvaro; Arévalo-Herrera, Myriam; Herrera, Sócrates
2016-08-30
Even though malaria incidence has decreased substantially in Guatemala since 2000, Guatemala remains one of the countries with the highest malaria transmission in Mesoamerica. Guatemala is committed to eliminating malaria as part of the initiative 'Elimination of Malaria in Mesoamerica and the Island of Hispaniola' (EMMIE); however, it is still in the control phase. During the past decade, the government strengthened malaria control activities including mass distribution of long-lasting insecticide-impregnated bed nets, early diagnosis and prompt treatment. This study aimed to determine the prevalence of malaria, including gametocytes, in three areas of Guatemala using active case detection (ACD) and quantitative polymerase chain reaction (qPCR). Cross-sectional surveys were conducted in three departments with varying transmission intensities: Escuintla, Alta Verapaz and Zacapa. Blood samples from 706 volunteers were screened for malaria using microscopy and qPCR which was also used to determine the prevalence of gametocytes among infected individuals. Results were collected and analysed using REDCap and R Project, respectively. Malaria was diagnosed by microscopy in only 2.8 % (4/141) of the volunteers from Escuintla. By contrast, qPCR detected a prevalence of 7.1 % (10/141) in the same volunteers, 8.4 % (36/429) in Alta Verapaz, and 5.9 % (8/136) in Zacapa. Overall, 7.6 % (54/706) of the screened individuals were positive, with an average parasitaemia level of 40.2 parasites/μL (range 1-1133 parasites/μL) and 27.8 % carried mature gametocytes. Fifty-seven percent (31/54) of qPCR positive volunteers were asymptomatic and out of the 42.6 % of symptomatic individuals, only one had a positive microscopy result. This study found a considerable number of asymptomatic P. vivax infections that were mostly submicroscopic, of which, approximately one-quarter harboured mature gametocytes. This pattern is likely to contribute to maintaining transmission across the
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2014-01-01
Background A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission. Methods and Findings 6,537 infants aged 6–12 wk and 8,923 children aged 5–17 mo were randomized to receive three doses of RTS,S/AS01 or comparator vaccine. VE against clinical malaria in children during the 18 mo after vaccine dose 3 (per protocol) was 46% (95% CI 42% to 50%) (range 40% to 77%; VE, p<0.01 across all sites). VE during the 20 mo after vaccine dose 1 (intention to treat [ITT]) was 45% (95% CI 41% to 49%). VE against severe malaria, malaria hospitalization, and all-cause hospitalization was 34% (95% CI 15% to 48%), 41% (95% CI 30% to 50%), and 19% (95% CI 11% to 27%), respectively (ITT). VE against clinical malaria in infants was 27% (95% CI 20% to 32%, per protocol; 27% [95% CI 21% to 33%], ITT), with no significant protection against severe malaria, malaria hospitalization, or all-cause hospitalization. Post-vaccination anti-circumsporozoite antibody geometric mean titer varied from 348 to 787 EU/ml across sites in children and from 117 to 335 EU/ml in infants (per protocol). VE waned over time in both age categories (Schoenfeld residuals p<0.001). The number of clinical and severe malaria cases averted per 1,000 children vaccinated ranged across sites from 37 to 2,365 and from −1 to 49, respectively; corresponding ranges among infants were −10 to 1,402 and −13 to 37, respectively (ITT). Meningitis was reported as a serious adverse event in 16/5,949 and 1/2,974 children and in 9/4,358 and 3/2,179 infants in the RTS,S/AS01 and control groups, respectively. Conclusions RTS,S/AS01 prevented many cases of clinical and severe malaria over the 18 mo after vaccine dose 3, with the highest impact in areas with the greatest malaria incidence. VE was higher in children than in infants, but even at
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Malaria vaccines: past, present and future.
von Seidlein, Lorenz; Bejon, Philip
2013-12-01
The currently available malaria control tools have allowed malaria elimination in many regions but there remain many regions where malaria control has made little progress. A safe and protective malaria vaccine would be a huge asset for malaria control. Despite the many challenges, efforts continue to design and evaluate malaria vaccine candidates. These candidates target different stages in the life cycle of Plasmodia. The most advanced vaccine candidates target the pre-erythrocytic stages in the life cycle of the parasite and include RTS,S/AS01, which has progressed through clinical development to the stage that it may be licensed in 2015. Attenuated whole-parasite vaccine candidates are highly protective, but there are challenges to manufacture and to administration. Cellular immunity is targeted by the prime-boost approach. Priming vectors trigger only modest responses but these are focused on the recombinant antigen. Boosting vectors trigger strong but broad non-specific responses. The heterologous sequence produces strong immunological responses to the recombinant antigen. Candidates that target the blood stages of the parasite have to result in an immune response that is more effective than the response to an infection to abort or control the infection of merozoites and hence disease. Finally, the sexual stages of the parasite offer another target for vaccine development, which would prevent the transmission of malaria. Today it seems unlikely that any candidate targeting a single antigen will provide complete protection against an organism of the complexity of Plasmodium. A systematic search for vaccine targets and combinations of antigens may be a more promising approach.
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NASA Technical Reports Server (NTRS)
Kiang, Richard K.; Adimi, Farida; Soika, Valerii; Nigro, Joseph
2007-01-01
These slides address the use of remote sensing in a public health application. Specifically, this discussion focuses on the of remote sensing to detect larval habitats to predict current and future endemicity and identify key factors that sustain or promote transmission of malaria in a targeted geographic area (Thailand). In the Malaria Modeling and Surveillance Project, which is part of the NASA Applied Sciences Public Health Applications Program, we have been developing techniques to enhance public health's decision capability for malaria risk assessments and controls. The main objectives are: 1) identification of the potential breeding sites for major vector species; 2) implementation of a risk algorithm to predict the occurrence of malaria and its transmission intensity; 3) implementation of a dynamic transmission model to identify the key factors that sustain or intensify malaria transmission. The potential benefits are: 1) increased warning time for public health organizations to respond to malaria outbreaks; 2) optimized utilization of pesticide and chemoprophylaxis; 3) reduced likelihood of pesticide and drug resistance; and 4) reduced damage to environment. !> Environmental parameters important to malaria transmission include temperature, relative humidity, precipitation, and vegetation conditions. The NASA Earth science data sets that have been used for malaria surveillance and risk assessment include AVHRR Pathfinder, TRMM, MODIS, NSIPP, and SIESIP. Textural-contextual classifications are used to identify small larval habitats. Neural network methods are used to model malaria cases as a function of the remotely sensed parameters. Hindcastings based on these environmental parameters have shown good agreement to epidemiological records. Discrete event simulations are used for modeling the detailed interactions among the vector life cycle, sporogonic cycle and human infection cycle, under the explicit influences of selected extrinsic and intrinsic factors
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Alves, Joana; Roque, Ana Luísa; Cravo, Pedro; Valdez, Tomás; Jelinek, Tomas; do Rosário, Virgílio E; Arez, Ana Paula
2006-01-01
Background Malaria has come near eradication at archipelago of Cabo Verde in 1970. Infections are now only observed in Santiago, where outbreaks occur. In these islands, malaria is considered by the international community as being of limited risk and, therefore, no prophylaxis is recommended. Since the understanding of factors that determine malaria outbreaks are crucial for controlling the disease, the present study aimed to investigate if the malaria infections observed in Santiago Island are maintained in isolated foci and in asymptomatic individuals. Methods The occurrence of asymptomatic carriers in villages with history of malaria as well as the level of exposure of these populations were investigated using PCR and serological analyses. Results Results indicate that malaria is maintained as asymptomatic and sub-patent infections and that the majority of the circulating parasite populations harbour chloroquine-resistant mutations. Conclusion These observations highlight the alarming prospect of malaria to become a serious public health problem and underscore the need for a tighter surveillance. PMID:16630349
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Voordouw, Maarten J; Anholt, Bradley R; Taylor, Pam J; Hurd, Hilary
2009-01-01
Background Trade-offs between anti-parasite defence mechanisms and other life history traits limit the evolution of host resistance to parasites and have important implications for understanding diseases such as malaria. Mosquitoes have not evolved complete resistance to malaria parasites and one hypothesis is that anti-malaria defence mechanisms are costly. Results We used matrix population models to compare the population growth rates among lines of Anopheles gambiae that had been selected for resistance or high susceptibility to the rodent malaria parasite, Plasmodium yoelii nigeriensis. The population growth rate of the resistant line was significantly lower than that of the highly susceptible and the unselected control lines, regardless of whether mosquitoes were infected with Plasmodium or not. The lower population growth of malaria-resistant mosquitoes was caused by reduced post blood-feeding survival of females and poor egg hatching. Conclusion With respect to eradicating malaria, the strategy of releasing Plasmodium-resistant Anopheles mosquitoes is unlikely to be successful if the costs of Plasmodium-resistance in the field are as great as the ones measured in this study. High densities of malaria-resistant mosquitoes would have to be maintained by continuous release from captive breeding facilities. PMID:19379508
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Active case detection for malaria elimination: a survey among Asia Pacific countries
2013-01-01
Background Moving from malaria control to elimination requires national malaria control programmes to implement strategies to detect both symptomatic and asymptomatic cases in the community. In order to do this, malaria elimination programmes follow up malaria cases reported by health facilities to carry out case investigations that will determine the origin of the infection, whether it has been imported or is due to local malaria transmission. If necessary, the malaria programme will also carry out active surveillance to find additional malaria cases in the locality to prevent further transmission. To understand current practices and share information on malaria elimination strategies, a survey specifically addressing country policies on case investigation and reactive case detection was carried out among fourteen countries of the Asia Pacific Malaria Elimination Network (APMEN). Methods A questionnaire was distributed to the malaria control programme managers amongst 14 countries in the Asia Pacific who have national or sub-national malaria elimination goals. Results Results indicate that there are a wide variety of case investigation and active case detection activities employed by the 13 countries that responded to the survey. All respondents report conducting case investigation as part of surveillance activities. More than half of these countries conduct investigations for each case. Over half aim to accomplish the investigation within one to two days of a case report. Programmes collect a broad array of demographic data during investigation procedures and definitions for imported cases are varied across respondents. Some countries report intra-national (from a different province or district) importation while others report only international importation (from a different country). Reactive case detection in respondent countries is defined as screening households within a pre-determined radius in order to identify other locally acquired infections, whether
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Dlamini, Sabelo V; Liao, Chien-Wei; Dlamini, Zandile H; Siphepho, Jameson S; Cheng, Po-Ching; Chuang, Ting-Wu; Fan, Chia-Kwung
2017-04-01
Although malaria control programs have made rapid progress recently, they neglect important social and behavioral factors associated with the disease. Social, political, and cultural factors are involved in malaria control, and individuals in a community may be comfortable in behaving in ways that, to an outsider, may seem contrary to commonly held perceptions. Malaria control efforts can no longer afford to overlook the multidimensional human contexts that create and support varying notions of malaria and its prevention, treatment, and control. This study aimed to assess the knowledge and perceptions of malaria issues in the community, and to identify practices that support or hinder the progress of malaria control programs. A triangulation study involving individual interviews, focus group discussions, and observatory analysis between 2003 and 2010 at Lomahasha, a malarious community on the eastern border of Swaziland and Mozambique, was conducted. Results indicated that a high knowledge level and good perception of the disease were observed in the age group of < 40 years, contrary to those in higher age groups, among the Lomahasha community members. However, behavior of certain community groups includes practices that are not supportive of the national control program's aspirations, such as delay in seeking medical attention, staying outdoors until late, maintaining stagnant water in roadside excavations, and seeking medical assistance from wrong sources. Malpractices are more commonly observed among men, boys, and those who drink alcohol. This study suggests a thorough community diagnosis before all intervention programs for malaria control are instituted. Copyright © 2015. Published by Elsevier B.V.
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Combating severe malaria in African children*
Breman, J. G.; Campbell, C. C.
1988-01-01
An initiative to reduce childhood mortality due to malaria, diarrhoea and vaccine-preventable diseases, called the Africa Child Survival Initiative—Combatting Childhood Communicable Diseases (CCCD) project, was started in 1982 and is now operating in 13 African countries, 12 of which are endemic for malaria. The project's malaria control strategy relies on the use of drugs, mainly chloroquine, to prevent severe illness and death in children less than 5 years of age; chemoprophylaxis for pregnant women is also advised to prevent low birth weight in newborns. The strategy is based on WHO recommendations which focus on improved diagnosis and treatment of cases and chemoprophylaxis for pregnant women. In 9 out of the 13 CCCD countries the sensitivity of Plasmodium falciparum to chloroquine in children was investigated and a drug sensitivity surveillance network was established. In areas with chloroquine-resistant P. falciparum, treatment with chloroquine was found to decrease the temperature in febrile children and to greatly reduce the parasite density, thus preventing severe illness and possible death. Baseline surveys in 6 countries have shown a wide range of treatment practices, e.g., use of chloroquine in various doses without standard guidelines and the excessive use of quinine and chloroquine injections in some health units. As pregnant women are often not taking chemoprophylaxis, research has been started on alternative approaches to drug treatment to prevent the adverse effects of malaria on the fetus. Only 4 of the 12 malarious countries had malaria control units when their CCCD programme began and these were concerned mainly with vector control issues; 11 of 12 countries now have such units and a written CCCD malaria plan. These countries have now integrated malaria control activities into primary health care and have begun to implement standardized treatment and prevention practices that are described in their national CCCD malaria plans. PMID:3061675
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Mogeni, Polycarp; Williams, Thomas N; Omedo, Irene; Kimani, Domtila; Ngoi, Joyce M; Mwacharo, Jedida; Morter, Richard; Nyundo, Christopher; Wambua, Juliana; Nyangweso, George; Kapulu, Melissa; Fegan, Gregory; Bejon, Philip
2017-01-01
Abstract Background Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. Methods We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Results Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Conclusion Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls. PMID:28973672
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Comfort, Alison; Leegwater, Anthony; Nakhimovsky, Sharon; Kansembe, Henry; Hamainza, Busiku; Bwalya, Benson; Alilio, Martin; Johns, Ben; Olsho, Lauren
2017-01-04
Country-level evidence on the impact of malaria control on micro-economic outcomes is vital for mobilizing domestic and donor resources for malaria control. Using routinely available survey data could facilitate this investigation in a cost-efficient way. The authors used Malaria Indicator Surveys (MIS) and Living Conditions Monitoring Survey (LCMS) data from 2006 to 2010 for all 72 districts in Zambia to relate malaria control scale-up with household food spending (proxy for household well-being), educational attainment and agricultural production. The authors used two quasi-experimental designs: (1) a generalized propensity score for a continuous treatment variable (defined as coverage from owning insecticide-treated bed nets and/or receipt of indoor residual spraying); and, (2) a district fixed effects model to assess changes in the outcome relative to changes in treatment pre-post scale-up. The unit of analysis was at district level. The authors also conducted simulations post-analysis to assess statistical power. Micro-economic outcomes increased (33% increase in food spending) concurrently with malaria control coverage (62% increase) from 2006 to 2010. Despite using data from all 72 districts, both analytic methods yielded wide confidence intervals that do not conclusively link outcomes and malaria control coverage increases. The authors cannot rule out positive, null or negative effects. The upper bound estimates of the results show that if malaria control coverage increases from 60 to 70%, food spending could increase up to 14%, maize production could increase up to 57%, and years of schooling could increase up to 0.5 years. Simulations indicated that the generalized propensity score model did not have good statistical power. While it is technically possible to use routinely available survey data to relate malaria control scale-up and micro-economic outcomes, it is not clear from this analysis that meaningful results can be obtained when survey data are
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Malaria in selected non-Amazonian countries of Latin America.
Arevalo-Herrera, Myriam; Quiñones, Martha Lucia; Guerra, Carlos; Céspedes, Nora; Giron, Sandra; Ahumada, Martha; Piñeros, Juan Gabriel; Padilla, Norma; Terrientes, Zilka; Rosas, Angel; Padilla, Julio Cesar; Escalante, Ananias A; Beier, John C; Herrera, Socrates
2012-03-01
Approximately 170 million inhabitants of the American continent live at risk of malaria transmission. Although the continent's contribution to the global malaria burden is small, at least 1-1.2 million malaria cases are reported annually. Sixty percent of the malaria cases occur in Brazil and the other 40% are distributed in 20 other countries of Central and South America. Plasmodium vivax is the predominant species (74.2%) followed by P. falciparum (25.7%) and P. malariae (0.1%), and no less than 10 Anopheles species have been identified as primary or secondary malaria vectors. Rapid deforestation and agricultural practices are directly related to increases in Anopheles species diversity and abundance, as well as in the number of malaria cases. Additionally, climate changes profoundly affect malaria transmission and are responsible for malaria epidemics in some regions of South America. Parasite drug resistance is increasing, but due to bio-geographic barriers there is extraordinary genetic differentiation of parasites with limited dispersion. Although the clinical spectrum ranges from uncomplicated to severe malaria cases, due to the generally low to middle transmission intensity, features such as severe anemia, cerebral malaria and other complications appear to be less frequent than in other endemic regions and asymptomatic infections are a common feature. Although the National Malaria Control Programs (NMCP) of different countries differ in their control activities these are all directed to reduce morbidity and mortality by using strategies like health promotion, vector control and impregnate bed nets among others. Recently, international initiatives such as the Malaria Control Program in Andean-country Border Regions (PAMAFRO) (implemented by the Andean Organism for Health (ORAS) and sponsored by The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)) and The Amazon Network for the Surveillance of Antimalarial Drug Resistance (RAVREDA) (sponsored by
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Larvivorous fish for preventing malaria transmission
Walshe, Deirdre P; Garner, Paul; Abdel-Hameed Adeel, Ahmed A; Pyke, Graham H; Burkot, Tom
2013-01-01
Background Adult anopheline mosquitoes transmit Plasmodium parasites that cause malaria. Some fish species eat mosquito larvae and pupae. In disease control policy documents, the World Health Organization includes biological control of malaria vectors by stocking ponds, rivers, and water collections near where people live with larvivorous fish to reduce Plasmodium parasite transmission. The Global Fund finances larvivorous fish programmes in some countries, and, with increasing efforts in eradication of malaria, policy makers may return to this option. We therefore assessed the evidence base for larvivorous fish programmes in malaria control. Objectives Our main objective was to evaluate whether introducing larvivorous fish to anopheline breeding sites impacts Plasmodium parasite transmission. Our secondary objective was to summarize studies evaluating whether introducing larvivorous fish influences the density and presence of Anopheles larvae and pupae in water sources, to understand whether fish can possibly have an effect. Search methods We attempted to identify all relevant studies regardless of language or publication status (published, unpublished, in press, or ongoing). We searched the following databases: the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library; MEDLINE; EMBASE; CABS Abstracts; LILACS; and the metaRegister of Controlled Trials (mRCT) until 18 June 2013. We checked the reference lists of all studies identified by the above methods. We also examined references listed in review articles and previously compiled bibliographies to look for eligible studies. Selection criteria Randomized controlled trials and non-randomized controlled trials, including controlled before-and-after studies, controlled time series and controlled interrupted time series studies from malaria-endemic regions that introduced fish as a larvicide and reported on malaria in
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Malaria in selected non-Amazonian countries of Latin America
Arevalo-Herrera, Myriam; Quiñones, Martha Lucia; Guerra, Carlos; Céspedes, Nora; Giron, Sandra; Ahumada, Martha; Piñeros, Juan Gabriel; Padilla, Norma; Terrientes, Zilka; Rosas, Ángel; Padilla, Julio Cesar; Escalante, Ananias A.; Beier, John C.; Herrera, Socrates
2011-01-01
Approximately 170 million inhabitants of the American continent live at risk of malaria transmission. Although the continent’s contribution to the global malaria burden is small, at least 1 to 1.2 million malaria cases are reported annually. Sixty per cent of the malaria cases occur in Brazil and the other 40% are distributed in 20 other countries of Central and South America. Plasmodium vivax is the predominant species (74.2 %) followed by P. falciparum (25.7 %) and P. malariae (0.1%), and no less than 10 Anopheles species have been identified as primary or secondary malaria vectors. Rapid deforestation and agricultural practices are directly related to increases in Anopheles species diversity and abundance, as well as in the number of malaria cases. Additionally, climate changes profoundly affect malaria transmission and are responsible for malaria epidemics in some regions of South America. Parasite drug resistance is increasing, but due to bio-geographic barriers there is extraordinary genetic differentiation of parasites with limited dispersion. Although the clinical spectrum ranges from uncomplicated to severe malaria cases, due to the generally low to middle transmission intensity, features such as severe anemia, cerebral malaria and other complications appear to be less frequent than in other endemic regions and asymptomatic infections are a common feature. Although the National Malaria Control Programs (NMCP) of different countries differ in their control activities these are all directed to reduce morbidity and mortality by using strategies like health promotion, vector control and impregnate bed nets among others. Recently, international initiatives such as the Malaria Control Program in Andean-country Border Regions (PAMAFRO) (implemented by the Andean Organism for Health (ORAS) and sponsored by The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)) and The Amazon Network for the Surveillance of Antimalarial Drug Resistance (RAVREDA
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Messenger, Louisa A; Rowland, Mark
2017-05-22
While long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the cornerstones of malaria vector control throughout sub-Saharan Africa, there is an urgent need for the development of novel insecticide delivery mechanisms to sustain and consolidate gains in disease reduction and to transition towards malaria elimination and eradication. Insecticide-treated durable wall lining (ITWL) may represent a new paradigm for malaria control as a potential complementary or alternate longer-lasting intervention to IRS. ITWL can be attached to inner house walls, remain efficacious over multiple years and overcome some of the operational constraints of first-line control strategies, specifically nightly behavioural compliance required of LLINs and re-current costs and user fatigue associated with IRS campaigns. Initial experimental hut trials of insecticide-treated plastic sheeting reported promising results, achieving high levels of vector mortality, deterrence and blood-feeding inhibition, particularly when combined with LLINs. Two generations of commercial ITWL have been manufactured to date containing either pyrethroid or non-pyrethroid formulations. While some Phase III trials of these products have demonstrated reductions in malaria incidence, further large-scale evidence is still required before operational implementation of ITWL can be considered either in a programmatic or more targeted community context. Qualitative studies of ITWL have identified aesthetic value and observable entomological efficacy as key determinants of household acceptability. However, concerns have been raised regarding installation feasibility and anticipated cost-effectiveness. This paper critically reviews ITWL as both a putative mechanism of house improvement or more conventional intervention and discusses its future prospects as a method for controlling malaria and other vector-borne diseases.
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Oladeinde, Bankole Henry; Omoregie, Richard; Odia, Ikponmwosa; Oladeinde, Oladapo Babatunde
2012-01-01
Objectives To determine the prevalence of malaria and anemia among pregnant women attending a traditional birth center as well as the effect of herbal remedies, gravidity, age, educational background and malaria prevention methods on their prevalence. Methods Blood specimens were collected from 119 pregnant women attending a Traditional Birth Home in Benin City, Nigeria. Malaria parasitemia was diagnosed by microscopy while anemia was defined as hemoglobin concentration <11 g/dL. Results The prevalence of malaria infection was (OR=4.35 95% CI=1.213, 15.600; p=0.016) higher among primigravidae (92.1%). Pregnant women (38.5%) with tertiary level of education had significantly lower prevalence of malaria infection (p=0.002). Malaria significantly affected the prevalence of anemia (p<0.05). Anemia was associated with consumption of herbal remedies (OR=2.973; 95% CI=1.206, 7.330; p=0.017). The prevalence of malaria parasitemia and anemia were not affected by malaria prevention methods used by the participants. Conclusion The overall prevalence of malaria infection and anemia observed in this study were 78.9% and 46.2%, respectively. Higher prevalence of malaria infection was associated with primigravidae and lower prevalence with tertiary education of subjects. Anemia was associated with consumption of herbal remedies. There is urgent need to control the prevalence of malaria and anemia among pregnant women attending traditional birth homes. PMID:22811774
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Spatial analysis of malaria in Anhui province, China
Zhang, Wenyi; Wang, Liping; Fang, Liqun; Ma, Jiaqi; Xu, Youfu; Jiang, Jiafu; Hui, Fengming; Wang, Jianjun; Liang, Song; Yang, Hong; Cao, Wuchun
2008-01-01
Background Malaria has re-emerged in Anhui Province, China, and this province was the most seriously affected by malaria during 2005–2006. It is necessary to understand the spatial distribution of malaria cases and to identify highly endemic areas for future public health planning and resource allocation in Anhui Province. Methods The annual average incidence at the county level was calculated using malaria cases reported between 2000 and 2006 in Anhui Province. GIS-based spatial analyses were conducted to detect spatial distribution and clustering of malaria incidence at the county level. Results The spatial distribution of malaria cases in Anhui Province from 2000 to 2006 was mapped at the county level to show crude incidence, excess hazard and spatial smoothed incidence. Spatial cluster analysis suggested 10 and 24 counties were at increased risk for malaria (P < 0.001) with the maximum spatial cluster sizes at < 50% and < 25% of the total population, respectively. Conclusion The application of GIS, together with spatial statistical techniques, provide a means to quantify explicit malaria risks and to further identify environmental factors responsible for the re-emerged malaria risks. Future public health planning and resource allocation in Anhui Province should be focused on the maximum spatial cluster region. PMID:18847489
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Malaria Diagnostics in Clinical Trials
Murphy, Sean C.; Shott, Joseph P.; Parikh, Sunil; Etter, Paige; Prescott, William R.; Stewart, V. Ann
2013-01-01
Malaria diagnostics are widely used in epidemiologic studies to investigate natural history of disease and in drug and vaccine clinical trials to exclude participants or evaluate efficacy. The Malaria Laboratory Network (MLN), managed by the Office of HIV/AIDS Network Coordination, is an international working group with mutual interests in malaria disease and diagnosis and in human immunodeficiency virus/acquired immunodeficiency syndrome clinical trials. The MLN considered and studied the wide array of available malaria diagnostic tests for their suitability for screening trial participants and/or obtaining study endpoints for malaria clinical trials, including studies of HIV/malaria co-infection and other malaria natural history studies. The MLN provides recommendations on microscopy, rapid diagnostic tests, serologic tests, and molecular assays to guide selection of the most appropriate test(s) for specific research objectives. In addition, this report provides recommendations regarding quality management to ensure reproducibility across sites in clinical trials. Performance evaluation, quality control, and external quality assessment are critical processes that must be implemented in all clinical trials using malaria tests. PMID:24062484
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Nnko, Soori E; Whyte, Susan R; Geissler, Wenzel P; Aagaard-Hansen, Jens
2012-04-01
Despite existence of effective tools for malaria control, malaria continues to be one of the leading killer diseases especially among under-five year children and pregnant women in poor rural populations of Sub Saharan Africa. In Tanzania Mainland the disease contributes to 39.4% of the total OPD attendances. In terms of mortality, malaria is known to be responsible for more than one third of deaths among children of age below 5 years and also contributes for up to one fifth of deaths among pregnant women. This paper is based on a study conducted in a rural community along the shores of Lake Victoria in Mwanza region, North-Western Tanzania. The study explores reasons for scepticism and low uptake of insecticide treated mosquito nets (ITNs) that were promoted through social marketing strategy for malaria control prior to the introduction of long lasting nets (LLN). The paper breaks from traditional approach that tend to study low uptake of health interventions in terms of structural practical constraints--cost, accessibility, everyday priorities--or in terms of cognition--insufficient knowledge of benefits e.g. ignorance of public health messages. This paper has shown that, the majority of people who could afford the prices of ITNs and who knew where to obtain the insecticides did not necessarily buy them. This suggests that, although people tend to report cost-related factors as a barrier against the use of ITNs, there are other critical concerns at work. Without underestimating the practical factors, our study have recommended to consider critical examinations of those other concerns that hinder optimal utilization of ITN for malaria control, and the basis for those concerns.
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2014-01-01
Background This paper establishes empirical evidence relating the agriculture and health sectors in Uganda. The analysis explores linkages between agricultural management, malaria and implications for improving community health outcomes in rural Uganda. The goal of this exploratory work is to expand the evidence-base for collaboration between the agricultural and health sectors in Uganda. Methods The paper presents an analysis of data from the 2006 Uganda National Household Survey using a parametric multivariate Two-Limit Tobit model to identify correlations between agro-ecological variables including geographically joined daily seasonal precipitation records and household level malaria risk. The analysis of agricultural and environmental factors as they affect household malaria rates, disaggregated by age-group, is inspired by a complimentary review of existing agricultural malaria literature indicating a gap in evidence with respect to agricultural management as a form of malaria vector management. Crop choices and agricultural management practices may contribute to vector control through the simultaneous effects of reducing malaria transmission, improving housing and nutrition through income gains, and reducing insecticide resistance in both malaria vectors and agricultural pests. Results The econometric results show the existence of statistically significant correlations between crops, such as sweet potatoes/yams, beans, millet and sorghum, with household malaria risk. Local environmental factors are also influential- daily maximum temperature is negatively correlated with malaria, while daily minimum temperature is positively correlated with malaria, confirming trends in the broader literature are applicable to the Ugandan context. Conclusions Although not necessarily causative, the findings provide sufficient evidence to warrant purposefully designed work to test for agriculture health causation in vector management. A key constraint to modeling the
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The evil circle of poverty: a qualitative study of malaria and disability
2012-01-01
Background This article discusses the link between disability and malaria in a poor rural setting. Global malaria programmes and rehabilitation programmes are organized as vertical and separate programmes, and as such they focus on prevention, cure and control, and disability respectively. When looking at specific conditions and illnesses, the impairing long-term consequences of illness incidents during childhood are not questioned. Methods The study design was ethnographic with an open, exploratory approach. Data were collected in Mangochi District in Malawi through qualitative in-depth interviews and participant observation. Results Despite a local-based health service system, people living in poor rural areas are confronted with a multitude of barriers when accessing malaria prevention and treatment. Lack of skilled health personnel and equipment add to the general burden of poverty: insufficient knowledge about health care, problems connected to accessing the health facility in time, insufficient initiatives to prevent malaria attacks, and a general lack of attention to the long term disabling effects of a malaria attack. Conclusions This study points to the importance of building malaria programmes, research and statistics that take into consideration the consequences of permanent impairment after a malaria attack, as well as the context of poverty in which they often occur. In order to do so, one needs to develop methods for detecting people whose disabilities are a direct result of not having received health services after a malaria episode. This may be done through qualitative approaches in local communities and should also be supplemented by suitable surveys in order to estimate the problem on a larger scale. PMID:22236358
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Enhancing the application of effective malaria interventions in Africa through training.
Ijumba, Jasper N; Kitua, Andrew Y
2004-08-01
Africa bears more than 90% of the entire global malaria disease burden. Surprisingly, even with the current renewed interest in malaria prevention and control and the enabling environment resulting from the Roll Back Malaria initiative and the political commitment made by the African Presidents at the Abuja Summit, there are still no significant initiatives for strengthening capacity for malaria control through training within the African continent itself. The Center for Enhancement of Effective Malaria Interventions (CEEMI) has been established in Dar es Salaam, Tanzania for results-oriented training. It is intended to provide the needed skills for identifying and solving malaria control problems and providing incentives to malaria control workers in their work performance. The intention is to produce implementers with leadership skills for planning and managing malaria control activities and who can use strategic thinking in improving their work performance. To sustain political commitment and support and to sensitize the community on malaria issues, the CEEMI, in collaboration with the Ministry of Health (National Malaria Control Program), the Institute of Journalism and Mass Communication of the University of Dar es Salaam, and the Commonwealth Broadcasting Association have already conducted malaria seminars for Tanzanian Members of Parliament and journalists from Kenya, Malawi, Tanzania, and Uganda. Additionally, a diploma course in health communication is being developed for journalists and for the same purpose. Also being developed is a training module for "Council Malaria Focal Person." This is aimed at complementing the Roll Back Malaria initiative to meet the Abuja targets of reducing morbidity and mortality due to malaria by 50% by 2010. Copyright 2004 The American Society of Tropical Medicine and Hygiene
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A malaria transmission-directed model of mosquito life cycle and ecology
2011-01-01
Background Malaria is a major public health issue in much of the world, and the mosquito vectors which drive transmission are key targets for interventions. Mathematical models for planning malaria eradication benefit from detailed representations of local mosquito populations, their natural dynamics and their response to campaign pressures. Methods A new model is presented for mosquito population dynamics, effects of weather, and impacts of multiple simultaneous interventions. This model is then embedded in a large-scale individual-based simulation and results for local elimination of malaria are discussed. Mosquito population behaviours, such as anthropophily and indoor feeding, are included to study their effect upon the efficacy of vector control-based elimination campaigns. Results Results for vector control tools, such as bed nets, indoor spraying, larval control and space spraying, both alone and in combination, are displayed for a single-location simulation with vector species and seasonality characteristic of central Tanzania, varying baseline transmission intensity and vector bionomics. The sensitivities to habitat type, anthropophily, indoor feeding, and baseline transmission intensity are explored. Conclusions The ability to model a spectrum of local vector species with different ecologies and behaviours allows local customization of packages of interventions and exploration of the effect of proposed new tools. PMID:21999664
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The role of ENSO in understanding changes in Colombia's annual malaria burden by region, 1960–2006
Mantilla, Gilma; Oliveros, Hugo; Barnston, Anthony G
2009-01-01
Background Malaria remains a serious problem in Colombia. The number of malaria cases is governed by multiple climatic and non-climatic factors. Malaria control policies, and climate controls such as rainfall and temperature variations associated with the El Niño/Southern Oscillation (ENSO), have been associated with malaria case numbers. Using historical climate data and annual malaria case number data from 1960 to 2006, statistical models are developed to isolate the effects of climate in each of Colombia's five contrasting geographical regions. Methods Because year to year climate variability associated with ENSO causes interannual variability in malaria case numbers, while changes in population and institutional control policy result in more gradual trends, the chosen predictors in the models are annual indices of the ENSO state (sea surface temperature [SST] in the tropical Pacific Ocean) and time reference indices keyed to two major malaria trends during the study period. Two models were used: a Poisson and a Negative Binomial regression model. Two ENSO indices, two time reference indices, and one dummy variable are chosen as candidate predictors. The analysis was conducted using the five geographical regions to match the similar aggregation used by the National Institute of Health for its official reports. Results The Negative Binomial regression model is found better suited to the malaria cases in Colombia. Both the trend variables and the ENSO measures are significant predictors of malaria case numbers in Colombia as a whole, and in two of the five regions. A one degree Celsius change in SST (indicating a weak to moderate ENSO event) is seen to translate to an approximate 20% increase in malaria cases, holding other variables constant. Conclusion Regional differentiation in the role of ENSO in understanding changes in Colombia's annual malaria burden during 1960–2006 was found, constituting a new approach to use ENSO as a significant predictor of the
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Winstanley, Peter; Ward, Stephen
2006-01-01
Most malaria control strategies today depend on safe and effective drugs, as they have done for decades. But sensitivity to chloroquine, hitherto the workhorse of malaria chemotherapy, has rapidly declined throughout the tropics since the 1980s, and this drug is now useless in many high-transmission areas. New options for resource-constrained governments are few, and there is growing evidence that the burden from malaria has been increasing, as has malaria mortality in Africa. In this chapter, we have tried to outline the main pharmacological properties of current drugs, and their therapeutic uses and limitations. We have summarised the ways in which these drugs are employed, both in the formal health sector and in self-medication. We have briefly touched on the limitations of current drug development, but have tried to pick out a few promising drugs that are under development. Given that Plasmodium falciparum is the organism that kills, and that has developed multi-drug resistance, we have tended to focus upon it. Similarly, given that around 90% of global mortality from malaria occurs in Africa, there is the tendency to dwell on this continent. We give no apology for placing our emphasis upon the use of antimalarial drugs in endemic populations rather than their use for prophylaxis in travellers.
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Quartan malaria; Falciparum malaria; Biduoterian fever; Blackwater fever; Tertian malaria; Plasmodium ... Malaria is caused by a parasite that is passed to humans by the bite of infected anopheles ...
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[A history of malaria in modern Korea 1876-1945].
Yeo, Insok
2011-06-30
Although it is not certain when malaria began to appear in Korea, malaria is believed to have been an endemic disease from ancient times. It was Dr. H. N. Allen (1858-1932) who made the first description and diagnosis of malaria in terms of Western medicine. In his first year report (1885) of Korean Government Hospital he mentioned malaria as the most prevalent disease. Very effective anti-malarial drug quinine was imported and it made great contribution in treating malaria. After Japan had annexed Korea in 1910, policies for public health system were fundamentally revised. Japan assumed control of Korean medical institutions and built high-quality Western hospitals for the health care of Japanese residents. The infectious diseases which were under special surveillance were cholera, typhoid fever, dysentery, typhus, scarlet fever, smallpox, and paratyphoid fever. Among chronic infectious diseases tuberculosis and leprosy were those under special control. Malaria, however, was not one of these specially controlled infectious diseases although it was widely spread throughout the peninsula. But serious studies on malaria were carried out by Japanese medical scientists. In particular, a Japanese parasitologist Kobayasi Harujiro(1884-1969) carried out extensive studies on human parasites, including malaria, in Korea. According to his study, most of the malaria in Korea turned out to be tertian fever. In spite of its high prevalence, malaria did not draw much attention from the colonial authorities and no serious measure was taken since tertian fever is a mild form of malaria caused by Plasmodium vivax and is not so much fatal as tropical malaria caused by P. falciparum. And tertian malaria was easily controlled by taking quinine. Although the majority of malaria in Korea was tertian fever, other types were not absent. Quartan fever was not rarely reported in 1930s. The attitude of colonial authorities toward malaria in Korea was contrasted with that in Taiwan. After
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Malaria vaccine: the pros and cons.
Saleh, J A; Yusuph, H; Zailani, S B; Aji, B
2010-01-01
Malaria is an important parasitic disease of humans caused by infection with a parasite of the genus Polasmodium and transmitted by female anopheles. Infection caused by P. falciparum is the most serious of all the other species (P. ovale, P. vivax and P. malariae) especially in terms of morbidity and mortality hence the reason why most of the research has been focussed on this species. The disease affects up to about 40 per cent of the world's population with around 300-500 million people currently infected and mainly in the tropics. It has a high morbidity and mortality especially in resource-poor tropical and subtropical regions with an economic fall of about US$ 12 billion annually in Africa alone. relevant literatures were reviewed from medical journals, library search and internet source. Other relevant websites like PATH, Malaria Vaccine Initiative and Global Fund were also visited to source for information. The key words employed were: malaria, vaccine, anopheles mosquito, insecticide treated bed-nets, pyrethroids and Plasmodium. several studies have underscored the need to develop an effective human malaria vaccine for the control and possible eradication of malaria across the globe with the view to reduce the morbidity and mortality associated with the disease, improve on the social and economic losses and also protect those at risk. It is very obvious that the need for effective human malaria vaccine is not only to serve those living in malaria endemic regions but also the non-immune travellers especially those travelling to malaria endemic areas; this would offer cost effective means of preventing the disease, reducing the morbidity and mortality associated with it in addition to closing the gap left by other control measures. It is very obvious that there is no single control measure known to be effective in the control of malaria, hence the need for combination of more than one method with the aim of achieving synergy in the total control and possible
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Spatial targeting of interventions against malaria.
Carter, R.; Mendis, K. N.; Roberts, D.
2000-01-01
Malaria transmission is strongly associated with location. This association has two main features. First, the disease is focused around specific mosquito breeding sites and can normally be transmitted only within certain distances from them: in Africa these are typically between a few hundred metres and a kilometre and rarely exceed 2-3 kilometres. Second, there is a marked clustering of persons with malaria parasites and clinical symptoms at particular sites, usually households. In localities of low endemicity the level of malaria risk or case incidence may vary widely between households because the specific characteristics of houses and their locations affect contact between humans and vectors. Where endemicity is high, differences in human/vector contact rates between different households may have less effect on malaria case incidences. This is because superinfection and exposure-acquired immunity blur the proportional relationship between inoculation rates and case incidences. Accurate information on the distribution of malaria on the ground permits interventions to be targeted towards the foci of transmission and the locations and households of high malaria risk within them. Such targeting greatly increases the effectiveness of control measures. On the other hand, the inadvertent exclusion of these locations causes potentially effective control measures to fail. The computerized mapping and management of location data in geographical information systems should greatly assist the targeting of interventions against malaria at the focal and household levels, leading to improved effectiveness and cost-effectiveness of control. PMID:11196487
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Spatial targeting of interventions against malaria.
Carter, R; Mendis, K N; Roberts, D
2000-01-01
Malaria transmission is strongly associated with location. This association has two main features. First, the disease is focused around specific mosquito breeding sites and can normally be transmitted only within certain distances from them: in Africa these are typically between a few hundred metres and a kilometre and rarely exceed 2-3 kilometres. Second, there is a marked clustering of persons with malaria parasites and clinical symptoms at particular sites, usually households. In localities of low endemicity the level of malaria risk or case incidence may vary widely between households because the specific characteristics of houses and their locations affect contact between humans and vectors. Where endemicity is high, differences in human/vector contact rates between different households may have less effect on malaria case incidences. This is because superinfection and exposure-acquired immunity blur the proportional relationship between inoculation rates and case incidences. Accurate information on the distribution of malaria on the ground permits interventions to be targeted towards the foci of transmission and the locations and households of high malaria risk within them. Such targeting greatly increases the effectiveness of control measures. On the other hand, the inadvertent exclusion of these locations causes potentially effective control measures to fail. The computerized mapping and management of location data in geographical information systems should greatly assist the targeting of interventions against malaria at the focal and household levels, leading to improved effectiveness and cost-effectiveness of control.
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Kishore, J; Gupta, V K; Singh, S V; Garg, S; Kaur, Ravneet; Ingle, G K
2008-09-01
Malaria affects millions of people in India despite decades of efforts to control it. It has acquired greater importance in last two decades due to emergence of vector resistance, poor quality of care and low utilization of services. The study was conducted to improve the management of malaria by IEC and training activities in slum areas of Delhi. The baseline and post intervention data on knowledge, attitude, behavior and practices (KABP) regarding malaria was collected from 601 and 593 subjects respectively from two zones of Municipal Corporation of Delhi (MCD). At the same time, knowledge and skills regarding management of malaria were assessed among 15 health workers working in these two zones of MCD. An intervention package in the form of health education material for the community and training modules for the workers were designed and implemented. Post intervention data were collected. The knowledge about cause of malaria, season of malaria and breeding places of mosquito increased among community members after the intervention, which was found to be statistically significant. Similarly, more people were aware about the methods of prevention of mosquito breeding after the intervention. Methods like mosquito coil (post-64.92% vs pre-55.41%) and bet nets (post-24.96% vs pre-14.47%) were used by more people in post intervention phase. The Interval between onset of symptoms and seeking treatment decreased after the intervention from 1.66 days to 1.37 days. Among the workers, knowledge and skills regarding malaria management improved after the intervention. More blood slides were made, side effects of the treatment were explained to the patients and better compliance to treatment was observed in post intervention phase. IEC activities using attractive pamphlets to the community and on-job training of workers improves management of malaria and should be used more frequently more so in the slum areas for the success of the National Anti-Malaria Program.
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2014-01-01
Background Despite the significant reduction of malaria transmission in Rwanda, Ruhuha sector is still a highly endemic area for malaria. The objective of this activity was to explore and brainstorm the potential roles of various community stakeholders in malaria elimination. Methods Horizontal participatory approaches such as ‘open space’ have been deployed to explore local priorities, stimulate community contribution to project planning, and to promote local capacity to manage programmes. Two open space meetings were conducted with 62 and 82 participants in years 1 and 2, respectively. Participants included purposively selected community and local organizations’ representatives. Results Malaria was perceived as a health concern by the respondents despite the reported reduction in prevalence from 60 to 20% for cases at the local health centre. Some misconceptions of the cause of malaria and misuse of preventive strategies were noted. Poverty was deemed to be a contributing factor to malaria transmission, with suggestions that improvement of living conditions for poor families might help malaria reduction. Participants expressed willingness to contribute to malaria elimination and underscored the need for constant education, sensitization and mobilization towards malaria control in general. Active diagnosis, preventative strategies and prompt treatment of malaria cases were all mentioned by participants as ways to reduce malaria. Participants suggested that partnership of stakeholders at various levels could speed up programme activities. A community rewards system was deemed important to motivate engaged participants, i.e., community health workers and households. Establishment of malaria clubs in schools settings was also suggested as crucial to speed up community awareness and increase skills towards further malaria reduction. Conclusions This bottom-up approach was found useful in engaging the local community, enabling them to explore issues related to
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2012-01-01
Backgound Treatment of confirmed malaria patients with Artemisinin-based Combination Therapy (ACT) at remote areas is the goal of many anti-malaria programs. Introduction of effective and affordable malaria Rapid Diagnosis Test (RDT) in remote areas could be an alternative tool for malaria case management. This study aimed to assess performance of the OptiMAL dipstick for rapid malaria diagnosis in children under five. Methods Malaria symptomatic and asymptomatic children were recruited in a passive manner in two community clinics (CCs). Malaria diagnosis by microscopy and RDT were performed. Performance of the tests was determined. Results RDT showed similar ability (61.2%) to accurately diagnose malaria as microscopy (61.1%). OptiMAL showed a high level of sensitivity and specificity, compared with microscopy, during both transmission seasons (high & low), with a sensitivity of 92.9% vs. 74.9% and a specificity of 77.2% vs. 87.5%. Conclusion By improving the performance of the test through accurate and continuous quality control of the device in the field, OptiMAL could be suitable for use at CCs for the management and control of malaria. PMID:22647557
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Congenital malaria in Urabá, Colombia
2011-01-01
Background Congenital malaria has been considered a rare event; however, recent reports have shown frequencies ranging from 3% to 54.2% among newborns of mothers who had suffered malaria during pregnancy. There are only a few references concerning the epidemiological impact of this entity in Latin-America and Colombia. Objective The aim of the study was to measure the prevalence of congenital malaria in an endemic Colombian region and to determine some of its characteristics. Methods A prospective, descriptive study was carried out in the mothers who suffered malaria during pregnancy and their newborns. Neonates were clinically evaluated at birth and screened for Plasmodium spp. infection by thick smear from the umbilical cord and peripheral blood, and followed-up weekly during the first 21 days of postnatal life through clinical examinations and thick smears. Results 116 newborns were included in the study and 80 umbilical cord samples were obtained. Five cases of congenital infection were identified (four caused by P. vivax and one by P. falciparum), two in umbilical cord blood and three in newborn peripheral blood. One case was diagnosed at birth and the others during follow-up. Prevalence of congenital infection was 4.3%. One of the infected newborns was severely ill, while the others were asymptomatic and apparently healthy. The mothers of the newborns with congenital malaria had been diagnosed with malaria in the last trimester of pregnancy or during delivery, and also presented placental infection. Conclusions Congenital malaria may be a frequent event in newborns of mothers who have suffered malaria during pregnancy in Colombia. An association was found between congenital malaria and the diagnosis of malaria in the mother during the last trimester of pregnancy or during delivery, and the presence of placental infection. PMID:21846373
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High prevalence of asymptomatic malaria in south-eastern Bangladesh
2014-01-01
Background The WHO has reported that RDT and microscopy-confirmed malaria cases have declined in recent years. However, it is still unclear if this reflects a real decrease in incidence in Bangladesh, as particularly the hilly and forested areas of the Chittagong Hill Tract (CHT) Districts report more than 80% of all cases and deaths. surveillance and epidemiological data on malaria from the CHT are limited; existing data report Plasmodium falciparum and Plasmodium vivax as the dominant species. Methods A cross-sectional survey was conducted in the District of Bandarban, the southernmost of the three Hill Tracts Districts, to collect district-wide malaria prevalence data from one of the regions with the highest malaria endemicity in Bangladesh. A multistage cluster sampling technique was used to collect blood samples from febrile and afebrile participants and malaria microscopy and standardized nested PCR for diagnosis were performed. Demographic data, vital signs and splenomegaly were recorded. Results Malaria prevalence across all subdistricts in the monsoon season was 30.7% (95% CI: 28.3-33.2) and 14.2% (95% CI: 12.5-16.2) by PCR and microscopy, respectively. Plasmodium falciparum mono-infections accounted for 58.9%, P. vivax mono-infections for 13.6%, Plasmodium malariae for 1.8%, and Plasmodium ovale for 1.4% of all positive cases. In 24.4% of all cases mixed infections were identified by PCR. The proportion of asymptomatic infections among PCR-confirmed cases was 77.0%, oligosymptomatic and symptomatic cases accounted for only 19.8 and 3.2%, respectively. Significantly (p < 0.01) more asymptomatic cases were recorded among participants older than 15 years as compared to younger participants, whereas prevalence and parasite density were significantly (p < 0.01) higher in patients younger than 15 years. Spleen rate and malaria prevalence in two to nine year olds were 18.6 and 34.6%, respectively. No significant difference in malaria prevalence and
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Bennett, Adam; Yukich, Josh; Miller, John M; Keating, Joseph; Moonga, Hawela; Hamainza, Busiku; Kamuliwo, Mulakwa; Andrade-Pacheco, Ricardo; Vounatsou, Penelope; Steketee, Richard W; Eisele, Thomas P
2016-08-05
Four malaria indicator surveys (MIS) were conducted in Zambia between 2006 and 2012 to evaluate malaria control scale-up. Nationally, coverage of insecticide-treated nets (ITNs) and indoor residual spraying (IRS) increased over this period, while parasite prevalence in children 1-59 months decreased dramatically between 2006 and 2008, but then increased from 2008 to 2010. We assessed the relative effects of vector control coverage and climate variability on malaria parasite prevalence over this period. Nationally-representative MISs were conducted in April-June of 2006, 2008, 2010 and 2012 to collect household-level information on malaria control interventions such as IRS, ITN ownership and use, and child parasite prevalence by microscopic examination of blood smears. We fitted Bayesian geostatistical models to assess the association between IRS and ITN coverage and climate variability and malaria parasite prevalence. We created predictions of the spatial distribution of malaria prevalence at each time point and compared results of varying IRS, ITN, and climate inputs to assess their relative contributions to changes in prevalence. Nationally, the proportion of households owning an ITN increased from 37.8 % in 2006 to 64.3 % in 2010 and 68.1 % in 2012, with substantial heterogeneity sub-nationally. The population-adjusted predicted child malaria parasite prevalence decreased from 19.6 % in 2006 to 10.4 % in 2008, but rose to 15.3 % in 2010 and 13.5 % in 2012. We estimated that the majority of this prevalence increase at the national level between 2008 and 2010 was due to climate effects on transmission, although there was substantial heterogeneity at the provincial level in the relative contribution of changing climate and ITN availability. We predict that if climate factors preceding the 2010 survey were the same as in 2008, the population-adjusted prevalence would have fallen to 9.9 % nationally. These results suggest that a combination of climate factors
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Elimination of Plasmodium falciparum malaria in Tajikistan.
Kondrashin, Anatoly V; Sharipov, Azizullo S; Kadamov, Dilshod S; Karimov, Saifuddin S; Gasimov, Elkhan; Baranova, Alla M; Morozova, Lola F; Stepanova, Ekaterina V; Turbabina, Natalia A; Maksimova, Maria S; Morozov, Evgeny N
2017-05-30
Malaria was eliminated in Tajikistan by the beginning of the 1960s. However, sporadic introduced cases of malaria occurred subsequently probably as a result of transmission from infected mosquito Anopheles flying over river the Punj from the border areas of Afghanistan. During the 1970s and 1980s local outbreaks of malaria were reported in the southern districts bordering Afghanistan. The malaria situation dramatically changed during the 1990s following armed conflict and civil unrest in the newly independent Tajikistan, which paralyzed health services including the malaria control activities and a large-scale malaria epidemic occurred with more than 400,000 malaria cases. The malaria epidemic was contained by 1999 as a result of considerable financial input from the Government and the international community. Although Plasmodium falciparum constituted only about 5% of total malaria cases, reduction of its incidence was slower than that of Plasmodium vivax. To prevent increase in P. falciparum malaria both in terms of incidence and territory, a P. falciparum elimination programme in the Republic was launched in 200, jointly supported by the Government and the Global Fund for control of AIDS, tuberculosis and malaria. The main activities included the use of pyrethroids for the IRS with determined periodicity, deployment of mosquito nets, impregnated with insecticides, use of larvivorous fishes as a biological larvicide, implementation of small-scale environmental management, and use of personal protection methods by population under malaria risk. The malaria surveillance system was strengthened by the use of ACD, PCD, RCD and selective use of mass blood surveys. All detected cases were timely epidemiologically investigated and treated based on the results of laboratory diagnosis. As a result, by 2009, P. falciparum malaria was eliminated from all of Tajikistan, one year ahead of the originally targeted date. Elimination of P. falciparum also contributed towards
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Quantitative detection of PfHRP2 in saliva of malaria patients in the Philippines
2012-01-01
Background Malaria is a global health priority with a heavy burden of fatality and morbidity. Improvements in field diagnostics are needed to support the agenda for malaria elimination. Saliva has shown significant potential for use in non-invasive diagnostics, but the development of off-the-shelf saliva diagnostic kits requires best practices for sample preparation and quantitative insight on the availability of biomarkers and the dynamics of immunoassay in saliva. This pilot study measured the levels of the PfHRP2 in patient saliva to inform the development of salivary diagnostic tests for malaria. Methods Matched samples of blood and saliva were collected between January and May, 2011 from eight patients at Palawan Baptist Hospital in Roxas, Palawan, Philippines. Parasite density was determined from thick-film blood smears. Concentrations of PfHRP2 in saliva of malaria-positive patients were measured using a custom chemiluminescent ELISA in microtitre plates. Sixteen negative-control patients were enrolled at UCLA. A substantive difference between this protocol and previous related studies was that saliva samples were stabilized with protease inhibitors. Results Of the eight patients with microscopically confirmed P. falciparum malaria, seven tested positive for PfHRP2 in the blood using rapid diagnostic test kits, and all tested positive for PfHRP2 in saliva. All negative-control samples tested negative for salivary PfHRP2. On a binary-decision basis, the ELISA agreed with microscopy with 100 % sensitivity and 100 % specificity. Salivary levels of PfHRP2 ranged from 17 to 1,167 pg/mL in the malaria-positive group. Conclusion Saliva is a promising diagnostic fluid for malaria when protein degradation and matrix effects are mitigated. Systematic quantitation of other malaria biomarkers in saliva would identify those with the best clinical relevance and suitability for off-the-shelf diagnostic kits. PMID:22631858
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Ghosh, S K; Patil, Rajan R; Tiwari, S N
2012-01-01
Objective. A Socio-economic-political-cultural (SEPC) study was undertaken under the Roll Back Malaria (RBM) initiative to understand the process of programme implementation and how far in the changing malaria context, the broader environment has been understood and programme components have undergone changes. Material and Methods. Two studies were carried out; first in four villages under the primary health unit (PHU) Banavaralu in Tiptur Taluka in September 2002 and the second one in April 2003 in four villages in Chitradurga district, namely, Kappagere, Kellodu in Hosadurga Taluka, and Vani Vilas Puram and Kathrikenhally in Hiriyur Taluka. Focus group discussion and key interviews were adopted to collect the qualitative data. Results. Gender discrimination and lack of empowerment of women came out strongly in social analysis. In the rural elected bodies called Panchayats, the concept of health committees was not known. Health committees as one of the important statutory committees under every Panchayat were nonexistent in reality in these villages. Financial difficulties at Grama Panchayat level and also meager budget allocation for health have led to indifferent attitude of Panchayat members towards health. It was observed that there were generally no specific cultural practices in relation to malaria cure. Cultural and traditional practices in malaria-related issues were not predominant in the community except for some sporadic instances. Conclusion and Recommendation. SEPC study is an important indicator in malaria control programme. It is ultimately the community that takes the major decision directly or indirectly and the health authority must guide them in right direction.
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Ahorlu, Collins K; Koram, Kwadwo A; Seake-Kwawu, Atsu; Weiss, Mitchell G
2011-05-15
Intermittent preventive treatment (IPT) has recently been accepted as an important component of the malaria control strategy. Intermittent preventive treatment for children (IPTc) combined with timely treatment of malaria related febrile illness at home to reduce parasite prevalence and malaria morbidity in children aged between six and 60 months in a coastal community in Ghana. This paper reports persistence of reduced parasitaemia two years into the intervention. The baseline and year-one-evaluation findings were published earlier. The main objective in the second year was to demonstrate whether the two interventions would further reduce parasite prevalence and malaria-related febrile illness in the study population. This was an intervention study designed to compare baseline and evaluation findings without a control group. The study combined home-based delivery of intermittent preventive treatment for children (IPTc) aged 6 - 60 months and home treatment of suspected febrile malaria-related illness within 24 hours. All children aged 6-60 months received home-based delivery of intermittent preventive treatment using amodiaquine + artesunate, delivered at home by community assistants every four months (6 times in 24 months). Malaria parasite prevalence surveys were conducted before the first and after the third and sixth IPTc to the children. The evaluation surveys were done four months after the third and sixth IPTc was given. Parasite prevalence which reduced from 25% to 3.0% at year-one evaluation had reduced further from 3% to 1% at year-two-evaluation. At baseline, 13.8% of the children were febrile (axilary temperature of ≥ 37.5 °C) compared to 2.2% at year-one-evaluation while 2.1% were febrile at year-two-evaluation. The year-two-evaluation result indicates that IPTc given three times in a year (every four months) combined with timely treatment of febrile malaria illness, is effective to reduce malaria parasite prevalence in children aged 6 to 60 months
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A World Malaria Map: Plasmodium falciparum Endemicity in 2007
Hay, Simon I; Guerra, Carlos A; Gething, Peter W; Patil, Anand P; Tatem, Andrew J; Noor, Abdisalan M; Kabaria, Caroline W; Manh, Bui H; Elyazar, Iqbal R. F; Brooker, Simon; Smith, David L; Moyeed, Rana A; Snow, Robert W
2009-01-01
Background Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007. Methods and Findings A total of 8,938 P. falciparum parasite rate (PfPR) surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2–10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia), 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+), and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2−10 ≤ 5%). The vast majority (88%) of those living under stable risk in CSE Asia were also in this low endemicity class; a small remainder (11%) were in the intermediate endemicity class (PfPR2−10 > 5 to < 40%); and the remaining fraction (1%) in high endemicity (PfPR2−10 ≥ 40%) areas. High endemicity was widespread in the
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Migliani, R; Meynard, J-B; Milleliri, J-M; Verret, C; Rapp, C
2014-01-01
The French joint military health corps has long experience in malaria control. Many military physicians played an essential role in the 19th century: Maillot revolutionized malaria treatment by using quinine during the conquest of Algeria, and Laveran discovered the causal parasite (the genus Plasmodium) there. This experience continued under the direction of Laveran and the Sergent brothers on the eastern front in Greek Macedonia during World War I. The vast coordinated control plan established on this front from 1917 delivered the French infantrymen from malaria and led to victory over the Bulgarian forces, which capitulated in September 1918.
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Way, Albert G
2015-06-01
This essay tells the story of the Emory University Field Station, a malaria research station in southwest Georgia that operated from 1939 to 1958. Using the tools of environmental history and the history of science, it examines the station's founding, its fieldwork, and its place within the broader history of malaria control, eradication, and research. A joint effort of Emory University, the U.S. Public Health Service, and the Communicable Disease Center (CDC), this station was closely aligned with a broader movement of ideas about tropical diseases across the globe, but it also offers a case study of how science in the field can veer from mainstream thinking and official policy. As the CDC and other disease-fighting organizations were moving toward a global strategy of malaria eradication through the use of DDT, the Emory Field Station developed a postsanitarian approach to malaria. Drawing on resistance among American conservationists to environmental transformation in the name of malaria control, the station's staff embraced the science and worldview of ecology in an effort to lighten public health's hand on the land and to link human health to the environment in innovative, if sometimes opaque, ways. This essay, then, argues that the Emory Field Station represents an early confluence of ecology with the biomedical sciences, something very similar to what is now the important discipline of disease ecology.
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Sirima, Sodiomon B; Mordmüller, Benjamin; Milligan, Paul; Ngoa, Ulysse Ateba; Kironde, Fred; Atuguba, Frank; Tiono, Alfred B; Issifou, Saadou; Kaddumukasa, Mark; Bangre, Oscar; Flach, Clare; Christiansen, Michael; Bang, Peter; Chilengi, Roma; Jepsen, Søren; Kremsner, Peter G; Theisen, Michael
2016-08-31
GMZ2 is a recombinant protein malaria vaccine, comprising two blood-stage antigens of Plasmodium falciparum, glutamate-rich protein and merozoite surface protein 3. We assessed efficacy of GMZ2 in children in Burkina Faso, Gabon, Ghana and Uganda. Children 12-60months old were randomized to receive three injections of either 100μg GMZ2 adjuvanted with aluminum hydroxide or a control vaccine (rabies) four weeks apart and were followed up for six months to measure the incidence of malaria defined as fever or history of fever and a parasite density ⩾5000/μL. A cohort of 1849 children were randomized, 1735 received three doses of vaccine (868 GMZ2, 867 control-vaccine). There were 641 malaria episodes in the GMZ2/Alum group and 720 in the control group. In the ATP analysis, vaccine efficacy (VE), adjusted for age and site was 14% (95% confidence interval [CI]: 3.6%, 23%, p-value=0.009). In the ITT analysis, age-adjusted VE was 11.3% (95% CI 2.5%, 19%, p-value=0.013). VE was higher in older children. In GMZ2-vaccinated children, the incidence of malaria decreased with increasing vaccine-induced anti-GMZ2 IgG concentration. There were 32 cases of severe malaria (18 in the rabies vaccine group and 14 in the GMZ2 group), VE 27% (95% CI -44%, 63%). GMZ2 is the first blood-stage malaria vaccine to be evaluated in a large multicenter trial. GMZ2 was well tolerated and immunogenic, and reduced the incidence of malaria, but efficacy would need to be substantially improved, using a more immunogenic formulation, for the vaccine to have a public health role. Copyright © 2016 Elsevier Ltd. All rights reserved.
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2010-01-01
Background Scaling up insecticide-treated mosquito net (ITN) coverage is a key malaria control strategy even in conflict-affected countries [1,2]. Socio-economic factors influence access to ITNs whether subsidized or provided free to users. This study examines reported ITN purchasing, coverage, and usage in eastern Afghanistan and explores women's access to health information during the Taliban regime (1996-2001). This strengthens the knowledge base on household-level health choices in complex-emergency settings. Methods Fifteen focus group discussions (FGDs) and thirty in-depth interviews were conducted with men and women from ITN-owning and non-owning households. FGDs included rank ordering, pile sorting and focused discussion of malaria knowledge and ITN purchasing. Interviews explored general health issues, prevention and treatment practices, and women's malaria knowledge and concerns. Seven key informant interviews with health-related workers and a concurrent survey of 200 ITN-owning and 214 non-owning households were used to clarify or quantify findings. Results Malaria knowledge was similar among men and women and ITN owners and non-owners. Women reported obtaining health information through a variety of sources including clinic staff, their husbands who had easier access to information, and particularly female peers. Most participants considered ITNs very desirable, though not usually household necessities. ITN owners reported more household assets than non-owners. Male ITN owners and non-owners ranked rugs and ITNs as most desired, while women ranked personal assets such as jewellery highest. While men were primarily responsible for household decision-making and purchasing, older women exerted considerable influence. Widow-led and landless households reported most difficulties purchasing ITNs. Most participants wanted to buy ITNs only if they could cover all household members. When not possible, preferential usage was given to women and children
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Hay, S.I.; Omumbo, J.A.; Craig, M.H.; Snow, R. W.
2011-01-01
This review highlights the progress and current status of remote sensing (RS) and geographical information systems (GIS) as currently applied to the problem of Plasmodium falciparum malaria in sub-Saharan Africa (SSA). The burden of P. falciparum malaria in SSA is first summarized and then contrasted with the paucity of accurate and recent information on the nature and extent of the disease. This provides perspective on both the global importance of the pathogen and the potential for contribution of RS and GIS techniques. The ecology of P. falciparum malaria and its major anopheline vectors in SSA is then outlined, to provide the epidemiological background for considering disease transmission processes and their environmental correlates. Because RS and GIS are recent techniques in epidemiology, all mosquito-borne diseases are considered in this review in order to convey the range of ideas, insights and innovation provided. To conclude, the impact of these initial studies is assessed and suggestions provided on how these advances could be best used for malaria control in an appropriate and sustainable manner, with key areas for future research highlighted. PMID:10997207
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A research agenda for malaria eradication: vector control.
2011-01-25
Different challenges are presented by the variety of malaria transmission environments present in the world today. In each setting, improved control for reduction of morbidity is a necessary first step towards the long-range goal of malaria eradication and a priority for regions where the disease burden is high. For many geographic areas where transmission rates are low to moderate, sustained and well-managed application of currently available tools may be sufficient to achieve local elimination. The research needs for these areas will be to sustain and perhaps improve the effectiveness of currently available tools. For other low-to-moderate transmission regions, notably areas where the vectors exhibit behaviours such as outdoor feeding and resting that are not well targeted by current strategies, new interventions that target predictable features of the biology/ecologies of the local vectors will be required. To achieve elimination in areas where high levels of transmission are sustained by very efficient vector species, radically new interventions that significantly reduce the vectorial capacity of wild populations will be needed. Ideally, such interventions should be implemented with a one-time application with a long-lasting impact, such as genetic modification of the vectorial capacity of the wild vector population.
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Increasing malaria hospital admissions in Uganda between 1999 and 2009
2011-01-01
Background Some areas of Africa are witnessing a malaria transition, in part due to escalated international donor support and intervention coverage. Areas where declining malaria rates have been observed are largely characterized by relatively low baseline transmission intensity and rapid scaling of interventions. Less well described are changing patterns of malaria burden in areas of high parasite transmission and slower increases in control and treatment access. Methods Uganda is a country predominantly characterized by intense, perennial malaria transmission. Monthly pediatric admission data from five Ugandan hospitals and their catchments have been assembled retrospectively across 11 years from January 1999 to December 2009. Malaria admission rates adjusted for changes in population density within defined catchment areas were computed across three time periods that correspond to periods where intervention coverage data exist and different treatment and prevention policies were operational. Time series models were developed adjusting for variations in rainfall and hospital use to examine changes in malaria hospitalization over 132 months. The temporal changes in factors that might explain changes in disease incidence were qualitatively examined sequentially for each hospital setting and compared between hospital settings Results In four out of five sites there was a significant increase in malaria admission rates. Results from time series models indicate a significant month-to-month increase in the mean malaria admission rates at four hospitals (trend P < 0.001). At all hospitals malaria admissions had increased from 1999 by 47% to 350%. Observed changes in intervention coverage within the catchments of each hospital showed a change in insecticide-treated net coverage from <1% in 2000 to 33% by 2009 but accompanied by increases in access to nationally recommended drugs at only two of the five hospital areas studied. Conclusions The declining malaria disease
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Challenges facing drug development for malaria.
Craft, J Carl
2008-10-01
Malaria is a significant cause of morbidity and mortality in the developing world. Until recently malaria was winning but with increase in funding particularly from philanthropic groups the ability to control malaria is again possible. There are still many challenges to developing the next generations of anti-malarials. This article will briefly discuss the challenges and the advance that are being made.
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Soto, J; Toledo, J; Rodriquez, M; Sanchez, J; Herrera, R; Padilla, J; Berman, J
1998-08-01
Primaquine had a prophylactic efficacy of 90% to 95% against infection with Plasmodium falciparum and P. vivax in Indonesian settlers. To evaluate the efficacy of primaquine prophylaxis for protecting nonimmune persons from malaria. Randomized, double-blind, placebo-controlled field study. A malaria-endemic area in Colombia. 176 healthy, young, nonimmune adult male soldiers. Primaquine, 30 mg/d, or matching placebo during 15 weeks of patrol in the endemic area and 1 week afterward. Symptomatic parasitemia was determined over the 16-week intervention period and for 3 weeks in base camp. Protective efficacy in the primaquine group (122 participants) was 89% (95% CI, 75% to 96%) against all types of malaria, 94% (CI, 78% to 99%) against P. falciparum malaria, and 85% (CI, 57% to 95%) against P. vivax malaria. Six primaquine recipients had mild to moderate gastrointestinal distress, and three had severe distress. For prophylaxis against P. falciparum malaria, primaquine has an efficacy and toxicity competitive with those of standard agents. A potential advantage of primaquine is that prophylaxis may be discontinued 1 week after the recipient has left the endemic area.
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Corbellini, G
1998-06-01
The Third General Report of the Malaria Commission, printed in 1933, suggested for the control of malaria a strategy aimed to promote the acquisition of a "relative immunity" through a non radical treatment of the infected people living in highly endemic areas. The paper discusses the content of the Report and describes the scientific (empirical) premises on which it stood. Moreover, it illustrates the criticism that was directed against the immunological strategy and that eventually led to its abandonment.
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Gillet, Philippe; Mumba Ngoyi, Dieudonné; Lukuka, Albert; Kande, Viktor; Atua, Benjamin; van Griensven, Johan; Muyembe, Jean-Jacques; Jacobs, Jan; Lejon, Veerle
2013-01-01
Background In endemic settings, diagnosis of malaria increasingly relies on the use of rapid diagnostic tests (RDTs). False positivity of such RDTs is poorly documented, although it is especially relevant in those infections that resemble malaria, such as human African trypanosomiasis (HAT). We therefore examined specificity of malaria RDT products among patients infected with Trypanosoma brucei gambiense. Methodology/Principal Findings Blood samples of 117 HAT patients and 117 matched non-HAT controls were prospectively collected in the Democratic Republic of the Congo. Reference malaria diagnosis was based on real-time PCR. Ten commonly used malaria RDT products were assessed including three two-band and seven three-band products, targeting HRP-2, Pf-pLDH and/or pan-pLDH antigens. Rheumatoid factor was determined in PCR negative subjects. Specificity of the 10 malaria RDT products varied between 79.5 and 100% in HAT-negative controls and between 11.3 and 98.8% in HAT patients. For seven RDT products, specificity was significantly lower in HAT patients compared to controls. False positive reactions in HAT were mainly observed for pan-pLDH test lines (specificities between 13.8 and 97.5%), but also occurred frequently for the HRP-2 test line (specificities between 67.9 and 98.8%). The Pf-pLDH test line was not affected by false-positive lines in HAT patients (specificities between 97.5 and 100%). False positivity was not associated to rheumatoid factor, detected in 7.6% of controls and 1.2% of HAT patients. Conclusions/Significance Specificity of some malaria RDT products in HAT was surprisingly low, and constitutes a risk for misdiagnosis of a fatal but treatable infection. Our results show the importance to assess RDT specificity in non-targeted infections when evaluating diagnostic tests. PMID:23638201
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2012-01-01
Background The simian parasite Plasmodium knowlesi is recognized as a common cause of severe and fatal human malaria in Sabah, Malaysia, but is morphologically indistinguishable from and still commonly reported as Plasmodium malariae, despite the paucity of this species in Sabah. Since December 2008 Sabah Department of Health has recommended intravenous artesunate and referral to a general hospital for all severe malaria cases of any species. This paper reviews all malaria deaths in Sabah subsequent to the introduction of these measures. Reporting of malaria deaths in Malaysia is mandatory. Methods Details of reported malaria deaths during 2010-2011 were reviewed to determine the proportion of each Plasmodium species. Demographics, clinical presentations and management of severe malaria caused by each species were compared. Results Fourteen malaria deaths were reported, comprising seven Plasmodium falciparum, six P. knowlesi and one Plasmodium vivax (all PCR-confirmed). Of the six P. knowlesi deaths, five were attributable to knowlesi malaria and one was attributable to P. knowlesi-associated enterobacter sepsis. Patients with directly attributable P. knowlesi deaths (N = 5) were older than those with P. falciparum (median age 51 [IQR 50-65] vs 22 [IQR 9-55] years, p = 0.06). Complications in fatal P. knowlesi included respiratory distress (N = 5, 100%), hypotension (N = 4, 80%), and renal failure (N = 4, 80%). All patients with P. knowlesi were reported as P. malariae by microscopy. Only two of five patients with severe knowlesi malaria on presentation received immediate parenteral anti-malarial treatment. The patient with P. vivax-associated severe illness did not receive parenteral treatment. In contrast six of seven patients with severe falciparum malaria received immediate parenteral treatment. Conclusion Plasmodium knowlesi was responsible, either directly or through gram-negative bacteraemia, for almost half of malaria deaths in Sabah
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Nyasembe, Vincent O; Tchouassi, David P; Kirwa, Hillary K; Foster, Woodbridge A; Teal, Peter E A; Borgemeister, Christian; Torto, Baldwyn
2014-01-01
Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based synthetic odor baits in trapping outdoor populations of malaria vectors. Three plant-based lures ((E)-linalool oxide [LO], (E)-linalool oxide and (E)-β-ocimene [LO + OC], and a six-component blend comprising (E)-linalool oxide, (E)-β-ocimene, hexanal, β-pinene, limonene, and (E)-β-farnesene [Blend C]), were tested alongside an animal/human-based synthetic lure (comprising heptanal, octanal, nonanal, and decanal [Blend F]) and worn socks in a malaria endemic zone in the western part of Kenya. Mosquito Magnet-X (MM-X) and lightless Centre for Disease Control (CDC) light traps were used. Odor-baited traps were compared with traps baited with either solvent alone or solvent + carbon dioxide (controls) for 18 days in a series of randomized incomplete-block designs of days × sites × treatments. The interactive effect of plant and animal/human odor was also tested by combining LO with either Blend F or worn socks. Our results show that irrespective of trap type, traps baited with synthetic plant odors compared favorably to the same traps baited with synthetic animal odors and worn socks in trapping malaria vectors, relative to the controls. Combining LO and worn socks enhanced trap captures of Anopheles species while LO + Blend F recorded reduced trap capture. Carbon dioxide enhanced total trap capture of both plant- and animal/human-derived odors. However, significantly higher proportions of male and engorged female Anopheles gambiae s.l. were caught when the odor treatments did not include carbon dioxide. The results highlight the potential of plant-based odors and specifically linalool oxide, with or without carbon dioxide, for surveillance and mass trapping of malaria vectors.
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Howard, Natasha; Enayatullah, Sayed; Mohammad, Nader; Mayan, Ismail; Shamszai, Zohra; Rowland, Mark; Leslie, Toby
2015-11-04
Afghanistan has some of the worst maternal and infant mortality indicators in the world and malaria is a significant public health concern. Study objectives were to assess prevalence of malaria and anaemia, related knowledge and practices, and malaria prevention barriers among pregnant women in eastern Afghanistan. Three studies were conducted: (1) a clinical survey of maternal malaria, maternal anaemia, and neonatal birthweight in a rural district hospital delivery-ward; (2) a case-control study of malaria risk among reproductive-age women attending primary-level clinics; and (3) community surveys of malaria and anaemia prevalence, socioeconomic status, malaria knowledge and reported behaviour among pregnant women. Among 517 delivery-ward participants (1), one malaria case (prevalence 1.9/1000), 179 anaemia cases (prevalence 346/1000), and 59 low-birthweight deliveries (prevalence 107/1000) were detected. Anaemia was not associated with age, gravidity, intestinal parasite prevalence, or low-birthweight at delivery. Among 141 malaria cases and 1010 controls (2), no association was found between malaria infection and pregnancy (AOR 0.89; 95 % CI 0.57-1.39), parity (AOR 0.95; 95 % CI 0.85-1.05), age (AOR 1.02; 95 % CI 1.00-1.04), or anaemia (AOR 1.00; 95 % CI 0.65-1.54). Those reporting insecticide-treated net usage had 40 % reduced odds of malaria infection (AOR 0.60; 95 % CI 0.40-0.91). Among 530 community survey participants (3), malaria and anaemia prevalence were 3.9/1000 and 277/1000 respectively, with 34/1000 experiencing severe anaemia. Despite most women having no formal education, malaria knowledge was high. Most expressed reluctance to take malaria preventive medication during pregnancy, deeming it potentially unsafe. Given the low malaria risk and reported avoidance of medication during pregnancy, intermittent preventive treatment is hard to justify or implement. Preventive strategy should instead focus on long-lasting insecticidal nets for all pregnant
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Malaria in gold-mining areas in Colombia
Castellanos, Angélica; Chaparro-Narváez, Pablo; Morales-Plaza, Cristhian David; Alzate, Alberto; Padilla, Julio; Arévalo, Myriam; Herrera, Sócrates
2016-01-01
Gold-mining may play an important role in the maintenance of malaria worldwide. Gold-mining, mostly illegal, has significantly expanded in Colombia during the last decade in areas with limited health care and disease prevention. We report a descriptive study that was carried out to determine the malaria prevalence in gold-mining areas of Colombia, using data from the public health surveillance system (National Health Institute) during the period 2010-2013. Gold-mining was more prevalent in the departments of Antioquia, Córdoba, Bolívar, Chocó, Nariño, Cauca, and Valle, which contributed 89.3% (270,753 cases) of the national malaria incidence from 2010-2013 and 31.6% of malaria cases were from mining areas. Mining regions, such as El Bagre, Zaragoza, and Segovia, in Antioquia, Puerto Libertador and Montelíbano, in Córdoba, and Buenaventura, in Valle del Cauca, were the most endemic areas. The annual parasite index (API) correlated with gold production (R2 0.82, p < 0.0001); for every 100 kg of gold produced, the API increased by 0.54 cases per 1,000 inhabitants. Lack of malaria control activities, together with high migration and proliferation of mosquito breeding sites, contribute to malaria in gold-mining regions. Specific control activities must be introduced to control this significant source of malaria in Colombia. PMID:26814645
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Malaria in gold-mining areas in Colombia.
Castellanos, Angélica; Chaparro-Narváez, Pablo; Morales-Plaza, Cristhian David; Alzate, Alberto; Padilla, Julio; Arévalo, Myriam; Herrera, Sócrates
2016-01-01
Gold-mining may play an important role in the maintenance of malaria worldwide. Gold-mining, mostly illegal, has significantly expanded in Colombia during the last decade in areas with limited health care and disease prevention. We report a descriptive study that was carried out to determine the malaria prevalence in gold-mining areas of Colombia, using data from the public health surveillance system (National Health Institute) during the period 2010-2013. Gold-mining was more prevalent in the departments of Antioquia, Córdoba, Bolívar, Chocó, Nariño, Cauca, and Valle, which contributed 89.3% (270,753 cases) of the national malaria incidence from 2010-2013 and 31.6% of malaria cases were from mining areas. Mining regions, such as El Bagre, Zaragoza, and Segovia, in Antioquia, Puerto Libertador and Montelíbano, in Córdoba, and Buenaventura, in Valle del Cauca, were the most endemic areas. The annual parasite index (API) correlated with gold production (R2 0.82, p < 0.0001); for every 100 kg of gold produced, the API increased by 0.54 cases per 1,000 inhabitants. Lack of malaria control activities, together with high migration and proliferation of mosquito breeding sites, contribute to malaria in gold-mining regions. Specific control activities must be introduced to control this significant source of malaria in Colombia.
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Chipukuma, Helen Mwiinga; Zulu, Joseph Mumba; Jacobs, Choolwe; Chongwe, Gershom; Chola, Mumbi; Halwiindi, Hikabasa; Zgambo, Jessy; Michelo, Charles
2018-05-08
Community health workers (CHWs) are an important human resource in improving coverage of and success to interventions aimed at reducing malaria incidence. Evidence suggests that the performance of CHWs in malaria programs varies in different contexts. However, comprehensive frameworks, based on systematic reviews, to guide the analysis of determinants of performance of CHWs in malaria prevention and control programs are lacking. We systematically searched Google Scholar, Science Direct, and PubMed including reference lists that had English language publications. We included 16 full text articles that evaluated CHW performance in malaria control. Search terms were used and studies that had performance as an outcome of interest attributed to community-based interventions done by CHWs were included. Sixteen studies were included in the final review and were mostly on malaria Rapid Diagnosis and Treatment, as well as adherence to referral guidelines. Factors determining performance and effective implementation of CHW malaria programs included health system factors such as nature of training of CHWs; type of supervision including feedback process; availability of stocks, supplies, and job aids; nature of work environment and reporting systems; availability of financial resources and transport systems; types of remuneration; health staff confidence in CHWs; and workload. In addition, community dynamics such as nature of community connectedness and support from the community and utilization of services by the community also influenced performance. Furthermore, community health worker characteristics such marital status, sex, and CHW confidence levels also shaped CHW performance. Effectively analyzing and promoting the performance of CHWs in malaria prevention and control programs may require adopting a framework that considers health systems and community factors as well as community health worker characteristics.
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Changing Malaria Prevalence on the Kenyan Coast since 1974: Climate, Drugs and Vector Control
Snow, Robert W.; Kibuchi, Eliud; Karuri, Stella W.; Sang, Gilbert; Gitonga, Caroline W.; Mwandawiro, Charles; Bejon, Philip; Noor, Abdisalan M.
2015-01-01
Background Progress toward reducing the malaria burden in Africa has been measured, or modeled, using datasets with relatively short time-windows. These restricted temporal analyses may miss the wider context of longer-term cycles of malaria risk and hence may lead to incorrect inferences regarding the impact of intervention. Methods 1147 age-corrected Plasmodium falciparum parasite prevalence (PfPR2-10) surveys among rural communities along the Kenyan coast were assembled from 1974 to 2014. A Bayesian conditional autoregressive generalized linear mixed model was used to interpolate to 279 small areas for each of the 41 years since 1974. Best-fit polynomial splined curves of changing PfPR2-10 were compared to a sequence of plausible explanatory variables related to rainfall, drug resistance and insecticide-treated bed net (ITN) use. Results P. falciparum parasite prevalence initially rose from 1974 to 1987, dipped in 1991–92 but remained high until 1998. From 1998 onwards prevalence began to decline until 2011, then began to rise through to 2014. This major decline occurred before ITNs were widely distributed and variation in rainfall coincided with some, but not all, short-term transmission cycles. Emerging resistance to chloroquine and introduction of sulfadoxine/pyrimethamine provided plausible explanations for the rise and fall of malaria transmission along the Kenyan coast. Conclusions Progress towards elimination might not be as predictable as we would like, where natural and extrinsic cycles of transmission confound evaluations of the effect of interventions. Deciding where a country lies on an elimination pathway requires careful empiric observation of the long-term epidemiology of malaria transmission. PMID:26107772
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Gender aspects and women's participation in the control and management of malaria in central Sudan.
A/Rahman, S H; Mohamedani, A A; Mirgani, E M; Ibrahim, A M
1996-05-01
This work was designed to study the contribution of women in central Sudan in the control and management of malaria with particular emphasis on gender-related aspects that define women's role and participation. The Blue Nile Health Project (BNHP 1980-1990) was launched in 1980 mainly for control of water associated diseases in central Sudan. The BNHP model was chosen to conduct this work. The study showed that women were actively involved in the implementation of the BNHP strategies as health instructors (murshidat) who constituted 75% of the staff of BNHP unit of health education, as members of village health committees (VHC) where they constituted 40% of the VHC members and also as recipients of the project services. All murshidat were interviewed whereas multistage random sampling for VHC members and recipient women in 40 villages was used to select a sample which was interviewed. The results showed that the murshidat and VHC women members played a major role in the motivation, organization and health education of local communities prior to campaigns of environmental sanitation and vector control. Household commitments and difficulties in communication with the public were the main gender-related factors that contributed negatively to women's activities. Cases of malaria have more considerable socio-economic impact than other common diseases, especially with regard to women's household commitments and work. Recipient women were more concerned with aspects of self protection, management of family cases of malaria and health education programmes. They were less involved in drying mosquito breeding sites and spraying activities of insecticides which had been reluctantly accepted because of allergy and bad odour. Although the majority of women considered antimalarials to be less harmful than effects of malaria itself on pregnancy, they did not realize the role of malaria chemoprophylaxis during pregnancy. This needs more health education. The study showed that the
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2014-01-01
Background Malaria in pregnancy remains a major health problem. Placental malaria infection may cause pathophysiological changes in pregnancy and result in morphological changes to placental villi. Quantitative histomorphological image analysis of placental biopsies was performed to compare placental villous architecture between active or treated placental malaria cases and controls. Methods A total of 67 placentas were studied from three clinical groups: control patients who did not have malaria (n = 27), active (n = 14) and treated (n=26) malaria cases, including both Plasmodium falciparum and Plasmodium vivax infections. Image analysis of histological placental sections was performed using ImageJ software to measure the number and size (area) of terminal villi, perimeter measurement per villus and total perimeter per unit area, and number of capillaries per villus (vascularity). Histological features of placental malaria were scored and these results were correlated with malaria status and clinical outcomes. Results Villous size correlated with vascularity (p <0.0001) but was inversely correlated with observed villi per unit area, (p = 0.0001). Significantly greater villous area and vascularity was observed in UK controls. Indices of histological malaria infection were significantly greater in active versus treated malaria cases. Active placental malaria cases showed significantly smaller villous area (p <0.0084), vascularity (p <0.0139) and perimeter (p <0.0006) than treated malaria cases or controls, but significantly more villi per unit area (p <0.0001). Villous size in treated malaria cases was significantly larger than active placental malaria cases (p <0.001) and similar to controls. There was a significant relationship between villous number and anaemia at the time of infection (p <0.0034), but not placental weight, birth weight or gestational age at delivery. No differences were found between histology or villous morphology comparing infections with P
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Malaria in rural Mozambique. Part I: Children attending the outpatient clinic
Guinovart, Caterina; Bassat, Quique; Sigaúque, Betuel; Aide, Pedro; Sacarlal, Jahit; Nhampossa, Tacilta; Bardají, Azucena; Nhacolo, Ariel; Macete, Eusébio; Mandomando, Inácio; Aponte, John J; Menéndez, Clara; Alonso, Pedro L
2008-01-01
Background Malaria represents a huge burden for the health care services across Africa. Describing malaria attending health services contributes to quantify the burden and describe the epidemiology and clinical presentation. Methods Retrospective analysis of data collected through the Manhiça morbidity surveillance system (Mozambique) on all paediatric visits (<15 years) to the outpatient clinic from June 2003 to May 2005. Age-specific minimum community-based incidence rates (MCBIRs) of malaria were calculated using demographic surveillance system data. Malaria was defined as fever or history of fever in the preceding 24 hours with asexual Plasmodium falciparum parasitaemia of any density in the blood smear. Results A total of 94,941 outpatient visits were seen during the study period, of which 30.5% had malaria. Children younger than three years accounted for almost half of the total malaria cases and children aged ≥ 5 years represented 36.4% of the cases. Among children who presented with malaria, 56.7% had fever and among children who presented with fever or a history of fever only 37.2% had malaria. The geometric mean parasitaemia in malaria cases was 8582.2 parasites/μL, peaking in children aged two to three years. 13% of malaria cases had a PCV<25% and the mean PCV in malaria cases increased gradually with age, ranging from 27.8% in children aged 2–12 months to 34.4% in ≥ 5 years. The percentage of cases admitted or transferred showed a clear decreasing trend with age. MCBIRs of outpatient malaria per 1,000 child years at risk for the whole study period were of 394 in infants, 630 in children aged 1 to <5 years and 237 in children aged five years or more. A clustering of the cases was observed, whereby most children never had malaria, some had a few episodes and very few had many episodes. Conclusion Preventive measures should be targeted at children younger than three years, as they carry the highest burden of malaria. Children aged 5–15 years
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Nmor, Jephtha C; Sunahara, Toshihiko; Goto, Kensuke; Futami, Kyoko; Sonye, George; Akweywa, Peter; Dida, Gabriel; Minakawa, Noboru
2013-01-16
Identification of malaria vector breeding sites can enhance control activities. Although associations between malaria vector breeding sites and topography are well recognized, practical models that predict breeding sites from topographic information are lacking. We used topographic variables derived from remotely sensed Digital Elevation Models (DEMs) to model the breeding sites of malaria vectors. We further compared the predictive strength of two different DEMs and evaluated the predictability of various habitat types inhabited by Anopheles larvae. Using GIS techniques, topographic variables were extracted from two DEMs: 1) Shuttle Radar Topography Mission 3 (SRTM3, 90-m resolution) and 2) the Advanced Spaceborne Thermal Emission Reflection Radiometer Global DEM (ASTER, 30-m resolution). We used data on breeding sites from an extensive field survey conducted on an island in western Kenya in 2006. Topographic variables were extracted for 826 breeding sites and for 4520 negative points that were randomly assigned. Logistic regression modelling was applied to characterize topographic features of the malaria vector breeding sites and predict their locations. Model accuracy was evaluated using the area under the receiver operating characteristics curve (AUC). All topographic variables derived from both DEMs were significantly correlated with breeding habitats except for the aspect of SRTM. The magnitude and direction of correlation for each variable were similar in the two DEMs. Multivariate models for SRTM and ASTER showed similar levels of fit indicated by Akaike information criterion (3959.3 and 3972.7, respectively), though the former was slightly better than the latter. The accuracy of prediction indicated by AUC was also similar in SRTM (0.758) and ASTER (0.755) in the training site. In the testing site, both SRTM and ASTER models showed higher AUC in the testing sites than in the training site (0.829 and 0.799, respectively). The predictability of habitat types
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Chronic Malaria Revealed by a New Fluorescence Pattern on the Antinuclear Autoantibodies Test
Hommel, Benjamin; Charuel, Jean-Luc; Jaureguiberry, Stéphane; Arnaud, Laurent; Courtin, Regis; Kassab, Petra; Prendki, Virginie; Paris, Luc; Ghillani-Dalbin, Pascale; Thellier, Marc; Caumes, Eric; Amoura, Zahir; Mazier, Dominique; Musset, Lucile; Buffet, Pierre; Miyara, Makoto
2014-01-01
Background Several clinical forms of malaria such as chronic carriage, gestational malaria or hyper-reactive malarial splenomegaly may follow a cryptic evolution with afebrile chronic fatigue sometimes accompanied by anemia and/or splenomegaly. Conventional parasitological tests are often negative or not performed, and severe complications may occur. Extensive explorations of these conditions often include the search for antinuclear autoantibodies (ANA). Methods We analysed fluorescence patterns in the ANA test in patients with either chronic cryptic or acute symptomatic malaria, then conducted a one-year prospective study at a single hospital on all available sera drawn for ANA detections. We then identified autoantibodies differentially expressed in malaria patients and in controls using human protein microarray. Results We uncovered and defined a new, malaria-related, nucleo-cytoplasmic ANA pattern displaying the specific association of a nuclear speckled pattern with diffuse cytoplasmic perinuclearly-enhanced fluorescence. In the one-year prospective analysis, 79% of sera displaying this new nucleo-cytoplasmic fluorescence were from patients with malaria. This specific pattern, not seen in other parasitic diseases, allowed a timely reorientation of the diagnosis toward malaria. To assess if the autoantibody immune response was due to autoreactivity or molecular mimicry we isolated 42 autoantigens, targets of malarial autoantibodies. BLAST analysis indicated that 23 of recognized autoantigens were homologous to plasmodial proteins suggesting autoimmune responses directly driven by the plasmodial infection. Conclusion In patients with malaria in whom parasitological tests have not been performed recognition of this new, malaria-related fluorescence pattern on the ANA test is highly suggestive of the diagnosis and triggers immediate, easy confirmation and adapted therapy. PMID:24551116
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2017-01-01
Since the turn of the century, a remarkable expansion has been achieved in the range and effectiveness of products and strategies available to prevent, treat, and control malaria, including advances in diagnostics, drugs, vaccines, and vector control. These advances have once again put malaria elimination on the agenda. However, it is clear that even with the means available today, malaria control and elimination pose a formidable challenge in many settings. Thus, currently available resources must be used more effectively, and new products and approaches likely to achieve these goals must be developed. This paper considers tools (both those available and others that may be required) to achieve and maintain malaria elimination. New diagnostics are needed to direct treatment and detect transmission potential; new drugs and vaccines to overcome existing resistance and protect against clinical and severe disease, as well as block transmission and prevent relapses; and new vector control measures to overcome insecticide resistance and more powerfully interrupt transmission. It is also essential that strategies for combining new and existing approaches are developed for different settings to maximise their longevity and effectiveness in areas with continuing transmission and receptivity. For areas where local elimination has been recently achieved, understanding which measures are needed to maintain elimination is necessary to prevent rebound and the reestablishment of transmission. This becomes increasingly important as more countries move towards elimination. PMID:29190291
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2017-11-01
Since the turn of the century, a remarkable expansion has been achieved in the range and effectiveness of products and strategies available to prevent, treat, and control malaria, including advances in diagnostics, drugs, vaccines, and vector control. These advances have once again put malaria elimination on the agenda. However, it is clear that even with the means available today, malaria control and elimination pose a formidable challenge in many settings. Thus, currently available resources must be used more effectively, and new products and approaches likely to achieve these goals must be developed. This paper considers tools (both those available and others that may be required) to achieve and maintain malaria elimination. New diagnostics are needed to direct treatment and detect transmission potential; new drugs and vaccines to overcome existing resistance and protect against clinical and severe disease, as well as block transmission and prevent relapses; and new vector control measures to overcome insecticide resistance and more powerfully interrupt transmission. It is also essential that strategies for combining new and existing approaches are developed for different settings to maximise their longevity and effectiveness in areas with continuing transmission and receptivity. For areas where local elimination has been recently achieved, understanding which measures are needed to maintain elimination is necessary to prevent rebound and the reestablishment of transmission. This becomes increasingly important as more countries move towards elimination.
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2010-01-01
Background Despite continuous efforts by the government and private sectors, malaria is still a public health problem in rural Peninsular Malaysia. This study investigated household knowledge, attitude and practices (KAP) regarding malaria in two malaria endemic communities, forest-aboriginal and rural communities, in the Lipis district of Pahang state, Malaysia. Methods A descriptive cross-sectional study with a semi-structured questionnaire was carried out among 100 and 123 households from forest-aboriginal and rural areas, respectively. Results Knowledge about malaria and its transmission is significantly higher among the rural participants than the aborigines (86.2% vs 76%, p < 0.01). However, use of medicinal plants and beliefs in witchcraft and sorcery in treating febrile diseases were significantly higher among the aboriginal population (p < 0.01). There were no significant differences between the two communities in terms of the knowledge about malaria symptoms, attitudes towards its severity and practices in preventive measures against malaria by using mosquito bed nets. However, the knowledge and practice of different preventive measures to combat malaria, such as insecticide and the elimination of breeding areas, was significantly higher among the rural population than the aborigines (p < 0.001). Conclusions Both communities were aware of malaria as a disease, but knowledge, attitudes and practices were inadequate. Providing efficient health education to people residing in malaria endemic areas would improve their understanding about malaria prevention in order to bring about the elimination of malaria from the country. PMID:20497543
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Ding, Guisheng; Zhu, Guoding; Cao, Caiqun; Miao, Ping; Cao, Yuanyuan; Wang, Weiming; Gu, Yaping; Xu, Sui; Wang, Shengqiang; Zhou, Huayun; Cao, Jun
2018-04-12
Local malaria transmission has decreased rapidly since the National Malaria Elimination Action Plan was launched in China in 2010. However, imported malaria cases from Africa and Southeast Asia still occur in China due to overseas laborers. Diagnosis by microscopy is the gold standard for malaria and is used in most hospitals in China. However, the current capacity of microscopists to manage malaria cases in hospitals and public health facilities to meet the surveillance needs to eliminate and prevent the reintroduction of malaria is unknown. Malaria diagnoses were assessed by comparing the percentage of first visit and confirmed malaria diagnoses at Centers for Disease Control and Prevention (CDCs) and hospitals. The basic personnel information for public health departments and hospitals at different levels was investigated. The skills of microscopists for blood smear preparation and slide interpretation were also examined at the county and township levels. Inaccurate rate with 13.49% and 7.32%, respectively, in 2013 and 2014, from 341 and 355 reported cases from sub-provincial levels in Jiangsu province. Most of the 523 malaria cases reported in Nantong Prefecture from 2000 to 2014 involved patients who first visited county CDCs seeking treatment, however, none of these cases received confirmed diagnosis of malaria in townships or villages.The staff at county CDCs and hospitals with a higher education background performed better at making and interpreting blood smears than staff from townships. The network for malaria elimination in an entire province has been well established. However, an insufficient capacity for malaria diagnosis was observed, especially the preparing and reading the blood smears at the township and village levels, which is a challenge to achieving and maintaining malaria elimination.
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Rapid diagnostic tests for malaria
Daily, Jennifer; Hotte, Nora; Dolkart, Caitlin; Cunningham, Jane; Yadav, Prashant
2015-01-01
Abstract Maintaining quality, competitiveness and innovation in global health technology is a constant challenge for manufacturers, while affordability, access and equity are challenges for governments and international agencies. In this paper we discuss these issues with reference to rapid diagnostic tests for malaria. Strategies to control and eliminate malaria depend on early and accurate diagnosis. Rapid diagnostic tests for malaria require little training and equipment and can be performed by non-specialists in remote settings. Use of these tests has expanded significantly over the last few years, following recommendations to test all suspected malaria cases before treatment and the implementation of an evaluation programme to assess the performance of the malaria rapid diagnostic tests. Despite these gains, challenges exist that, if not addressed, could jeopardize the progress made to date. We discuss recent developments in rapid diagnostic tests for malaria, highlight some of the challenges and provide suggestions to address them. PMID:26668438
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Challenges and prospects for malaria elimination in the Greater Mekong Subregion
Cui, Liwang; Yan, Guiyun; Sattabongkot, Jetsumon; Chen, Bin; Cao, Yaming; Fan, Qi; Parker, Daniel; Sirichaisinthop, Jeeraphat; Su, Xin-zhuan; Yang, Henglin; Yang, Zhaoqing; Wang, Baomin; Zhou, Guofa
2011-01-01
Despite significant improvement in the malaria situation of the Greater Mekong Subregion (GMS), malaria control for the region continues to face a multitude of challenges. The extremely patchy malaria distribution, especially along international borders, makes disease surveillance and targeted control difficult. The vector systems are also diverse with dramatic differences in habitat ecology, biting behavior, and vectorial capacity, and there is a lack of effective transmission surveillance and control tools. Finally, in an era of heavy deployment of artemisinin-based combination therapies, the region acts as an epicenter of drug resistance, with the emergence of artemisinin resistant P. falciparum posing a threat to both regional and global malaria elimination campaigns. This problem is further exacerbated by the circulation of counterfeit and substandard artemisinin drugs. Accordingly, this Southeast Asian Malaria Research Center, consisting of a consortium of US and regional research institutions, has proposed four interlinked projects to address these most urgent problems in malaria control. The aims of these projects will help to substantially improve our understanding of malaria epidemiology, vector systems and their roles in malaria transmission, as well as the mechanisms of drug resistance in parasites. Through the training of next-generation scientists in malaria research, this program will help build up and strengthen regional research infrastructure and capacities, which are essential for sustained malaria control in this region. PMID:21515238
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Birbeck, Gretchen L; Molyneux, Malcolm E; Kaplan, Peter W; Seydel, Karl B; Chimalizeni, Yamikani F; Kawaza, Kondwani; Taylor, Terrie E
2010-12-01
Cerebral malaria, a disorder characterised by coma, parasitaemia, and no other evident cause of coma, is challenging to diagnose definitively in endemic regions that have high rates of asymptomatic parasitaemia and limited neurodiagnostic facilities. A recently described malaria retinopathy improves diagnostic specificity. We aimed to establish whether retinopathy-positive cerebral malaria is a risk factor for epilepsy or other neurodisabilities. Between 2005 and 2007, we did a prospective cohort study of survivors of cerebral malaria with malaria retinopathy in Blantyre, Malawi. Children with cerebral malaria were identified at the time of their index admission and age-matched to concurrently admitted children without coma or nervous system infection. Initially matching of cases to controls was 1:1 but, in 2006, enrolment criteria for cerebral malaria survivors were revised to limit inclusion to children with cerebral malaria and retinopathy on the basis of indirect ophthalmoscopic examination; matching was then changed to 1:2 and the revised inclusion criteria were applied retrospectively for children enrolled previously. Clinical assessments at discharge and standardised nurse-led follow-up every 3 months thereafter were done to identify children with new seizure disorders or other neurodisabilities. A Kaplan-Meier survival analysis was done for incident epilepsy. 132 children with retinopathy-positive cerebral malaria and 264 age-matched, non-comatose controls were followed up for a median of 495 days (IQR 195-819). 12 of 132 cerebral malaria survivors developed epilepsy versus none of 264 controls (odds ratio [OR] undefined; p<0·0001). 28 of 121 cerebral malaria survivors developed new neurodisabilities, characterised by gross motor, sensory, or language deficits, compared with two of 253 controls (OR 37·8, 95% CI 8·8-161·8; p<0·0001). The risk factors for epilepsy in children with cerebral malaria were a higher maximum temperature (39·4°C [SD 1·2] vs
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Minta, Anna A; Landman, Keren Z; Mwandama, Dyson A; Shah, Monica P; Eng, Jodi L Vanden; Sutcliffe, James F; Chisaka, Joseph; Lindblade, Kim A; Mathanga, Don P; Steinhardt, Laura C
2017-10-02
Long-lasting insecticidal nets (LLINs) are a cornerstone of malaria prevention. Holes develop in LLINs over time and compromise their physical integrity, but how holes affect malaria transmission risk is not well known. After a nationwide mass LLIN distribution in July 2012, a study was conducted to assess the relationship between LLIN damage and malaria. From March to September 2013, febrile children ages 6-59 months who consistently slept under LLINs (every night for 2 weeks before illness onset) were enrolled in a case-control study at Machinga District Hospital outpatient department. Cases were positive for Plasmodium falciparum asexual parasites by microscopy while controls were negative. Digital photographs of participants' LLINs were analysed using an image-processing programme to measure holes. Total hole area was classified by quartiles and according to the World Health Organization's proportionate hole index (pHI) cut-offs [< 79 cm 2 (good), 80-789 cm 2 (damaged), and > 790 cm 2 (too torn)]. Number of holes by location and size, and total hole area, were compared between case and control LLINs using non-parametric analyses and logistic regression. Of 248 LLINs analysed, 97 (39%) were from cases. Overall, 86% of LLINs had at least one hole. The median number of holes of any size was 9 [interquartile range (IQR) 3, 22], and most holes were located in the lower halves of the nets [median 7 (IQR 2, 16)]. There were no differences in number or location of holes between LLINs used by cases and controls. The median total hole area was 10 cm 2 (IQR 2, 125) for control LLINs and 8 cm 2 (IQR 2, 47) for case LLINs (p = 0.10). Based on pHI, 109 (72%) control LLINs and 83 (86%) case LLINs were in "good" condition. Multivariable modeling showed no association between total hole area and malaria, controlling for child age, caregiver education, and iron versus thatched roof houses. LLIN holes were not associated with increased odds of malaria in this study
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Charunwatthana, Prakaykaew; Faiz, M. Abul; Ruangveerayut, Ronnatrai; Maude, Richard; Rahman, M. Ridwanur; Roberts, L. Jackson; Moore, Kevin; Yunus, Emran Bin; Hoque, M. Gofranul; Hasan, Mahatab Uddin; Lee, Sue J.; Pukrittayakamee, Sasithon; Newton, Paul N.; White, Nicholas J.; Day, Nicholas P.J.; Dondorp, Arjen M.
2009-01-01
Objective Markers of oxidative stress are reported to be increased in severe malaria. It has been suggested that the antioxidant N-acetylcysteine (NAC) may be beneficial in treatment. We studied the efficacy and safety of parenteral N-acetylcysteine as an adjunct to artesunate treatment of severe falciparum malaria. Design A randomized double-blind placebo controlled trial on the use of high dose intravenous NAC as adjunctive treatment to artesunate. Setting A provincial hospital in Western Thailand and a tertiary referral hospital in Chittagong, Bangladesh. Patients One hundred and eight adult patients with severe falciparum malaria. Interventions Patients were randomized to receive N-acetylcysteine or placebo as adjunctive treatment to intravenous artesunate. Measurements and main results A total of 56 patients were treated with NAC and 52 received placebo. NAC had no significant effect on mortality, lactate clearance times (p=0.74) or coma recovery times (p=0.46). Parasite clearance time was increased from 30h (range 6h to 144h) to 36h (range 6h to 120h) (p=0.03), but this could be explained by differences in admission parasitemia. Urinary F2-isoprostane metabolites, measured as a marker of oxidative stress, were increased in severe malaria compared to patients with uncomplicated malaria and healthy volunteers. Admission red cell rigidity correlated with mortality, but did not improve with NAC. Conclusion Systemic oxidative stress is increased in severe malaria. Treatment with N-acetylcysteine had no effect on outcome in patients with severe falciparum malaria in this setting. PMID:19114891
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Alonso, Sergi; Zulliger, Rose; Wagman, Joe; Saifodine, Abuchahama; Candrinho, Baltazar; Macete, Eusébio; Brew, Joe; Fornadel, Christen; Kassim, Hidayat; Loch, Lourdes; Sacoor, Charfudin; Varela, Kenyssony; Carty, Cara L; Robertson, Molly; Saute, Francisco
2018-01-01
Background Most of the reduction in malaria prevalence seen in Africa since 2000 has been attributed to vector control interventions. Yet increases in the distribution and intensity of insecticide resistance and higher costs of newer insecticides pose a challenge to sustaining these gains. Thus, endemic countries face challenging decisions regarding the choice of vector control interventions. Methods A cluster randomised trial is being carried out in Mopeia District in the Zambezia Province of Mozambique, where malaria prevalence in children under 5 is high (68% in 2015), despite continuous and campaign distribution of long-lasting insecticide-treated nets (LLINs). Study arm 1 will continue to use the standard, LLIN-based National Malaria Control Programme vector control strategy (LLINs only), while study arm 2 will receive indoor residual spraying (IRS) once a year for 2 years with a microencapsulated formulation of pirimiphos-methyl (Actellic 300 CS), in addition to the standard LLIN strategy (LLINs+IRS). Prior to the 2016 IRS implementation (the first of two IRS campaigns in this study), 146 clusters were defined and stratified per number of households. Clusters were then randomised 1:1 into the two study arms. The public health impact and cost-effectiveness of IRS intervention will be evaluated over 2 years using multiple methods: (1) monthly active malaria case detection in a cohort of 1548 total children aged 6–59 months; (2) enhanced passive surveillance at health facilities and with community health workers; (3) annual cross-sectional surveys; and (4) entomological surveillance. Prospective microcosting of the intervention and provider and societal costs will be conducted. Insecticide resistance status pattern and changes in local Anopheline populations will be included as important supportive outcomes. Discussion By evaluating the public health impact and cost-effectiveness of IRS with a non-pyrethroid insecticide in a high-transmission setting with
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Alam, Mohammad Shafiul; Kabir, Mohammad Moktadir; Hossain, Mohammad Sharif; Naher, Shamsun; Ferdous, Nur E Naznin; Khan, Wasif Ali; Mondal, Dinesh; Karim, Jahirul; Shamsuzzaman, A K M; Ahmed, Be-Nazir; Islam, Akramul; Haque, Rashidul
2016-11-11
Malaria is endemic in 13 districts of Bangladesh. A baseline malaria prevalence survey across the endemic districts of Bangladesh was conducted in 2007, when the prevalence was reported around 39.7 per 1000 population. After two rounds of Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)-funded intervention by the National Malaria Control Programme (NMCP) and a BRAC-led NGO consortium, a follow-up survey was conducted across the malaria-endemic districts of Bangladesh to measure the change in prevalence rate and in people's knowledge of malaria. The survey was carried out from August to November 2013 in 70 upazilas (sub-districts) of 13 malaria-endemic districts of Bangladesh, following the same multi-stage cluster sampling design and the same number of households enrolled during the baseline prevalence survey in 2007, to collect 9750 randomly selected blood samples. For on-the-spot diagnosis of malaria, a rapid diagnostic test was used. The household head or eldest person available was interviewed using a pre-coded structured questionnaire to collect data on the knowledge and awareness of malaria in the household. Based on a weighted calculation, the overall malaria prevalence was found to be 1.41 per 1000 population. The proportion of Plasmodium falciparum mono-infection was 77.78% while both Plasmodium vivax mono-infection and mixed infection of the two species were found to be 11.11%. Bandarban had the highest prevalence (6.67 per 1000 population). Knowledge of malaria signs, symptoms and mode of transmission were higher in the follow-up survey (97.26%) than the baseline survey. Use of bed nets for prevention of malaria was found to be high (90.15%) at respondent level. People's knowledge of selected parameters increased significantly during the follow-up survey compared to the baseline survey conducted in 2007. A reduced prevalence rate of malaria and increased level of knowledge were observed in the present malaria prevalence survey in Bangladesh.
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Chirombo, James; Lowe, Rachel; Kazembe, Lawrence
2014-01-01
Background After years of implementing Roll Back Malaria (RBM) interventions, the changing landscape of malaria in terms of risk factors and spatial pattern has not been fully investigated. This paper uses the 2010 malaria indicator survey data to investigate if known malaria risk factors remain relevant after many years of interventions. Methods We adopted a structured additive logistic regression model that allowed for spatial correlation, to more realistically estimate malaria risk factors. Our model included child and household level covariates, as well as climatic and environmental factors. Continuous variables were modelled by assuming second order random walk priors, while spatial correlation was specified as a Markov random field prior, with fixed effects assigned diffuse priors. Inference was fully Bayesian resulting in an under five malaria risk map for Malawi. Results Malaria risk increased with increasing age of the child. With respect to socio-economic factors, the greater the household wealth, the lower the malaria prevalence. A general decline in malaria risk was observed as altitude increased. Minimum temperatures and average total rainfall in the three months preceding the survey did not show a strong association with disease risk. Conclusions The structured additive regression model offered a flexible extension to standard regression models by enabling simultaneous modelling of possible nonlinear effects of continuous covariates, spatial correlation and heterogeneity, while estimating usual fixed effects of categorical and continuous observed variables. Our results confirmed that malaria epidemiology is a complex interaction of biotic and abiotic factors, both at the individual, household and community level and that risk factors are still relevant many years after extensive implementation of RBM activities. PMID:24991915
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Guintran, Jean-Olivier; Iata, Harry; Anderson, Karen; Nausien, Johnny; Gresty, Karryn J; Waters, Norman C.; Vestergaard, Lasse S.; Taleo, George; Cheng, Qin
2016-01-01
Background As part of efforts to eliminate malaria, Vanuatu has piloted the implementation of enhanced malaria surveillance and response strategies since 2011. This involves passive case detection (PCD) in health facilities, proactive case detection (Pro-ACD) and reactive case detection (Re-ACD) in communities using malaria rapid diagnostic tests (RDTs). While RDTs improve case management, their utility for detection of malaria infections in ACDs in this setting is unclear. Methods The utility of malaria RDTs as diagnostic tools was evaluated in PCD, in five rounds of Pro-ACDs and five rounds of Re-ACDs conducted in Tafea and Torba Provinces between 2011 and 2014. The number of malaria infections detected by RDTs was compared to that detected by PCR from collected used-RDTs. Results PCD in Tafea Province (2013) showed a RDT-positive rate of 0.21% (2/939) and a PCR-positive rate of 0.44% (2/453), indicating less than 1% of suspected malaria cases in Tafea Province were due to malaria. In Pro-ACDs conducted in Tafea and Torba Provinces, RDT-positive rates in 2013 and 2014 were 0.14% (3/2145) and 0% (0/2823), respectively, while the corresponding PCR-positive rates were 0.72% (9/1242) and 0.79% (9/1141). PCR identified villages in both provinces appearing to be transmission foci with a small number of low-density infections, mainly P. falciparum infections. In five rounds of Re-ACD, RDTs did not identify any additional infections while PCR detected only one among 173 subjects screened. Conclusions PCD and Pro-ACDs demonstrate that both Tafea and Torba Provinces in Vanuatu has achieved very low malaria prevalence. In these low-transmission areas, conducting Pro-ACD and Re-ACDs using RDTs appears not cost-effective and may have limited impact on interrupting malaria transmission due to the small number of infections identified by RDTs and considerable operational resources invested. More sensitive, field deployable and affordable diagnostic tools will improve malaria
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Tiffany, Amanda; Moundekeno, Faya Pascal; Traoré, Alexis; Haile, Melat; Sterk, Esther; Guilavogui, Timothée; Genton, Blaise; Serafini, Micaela; Grais, Rebecca F
2016-05-28
Malaria is one of the principal causes of morbidity and mortality in the Republic of Guinea, particularly in the highly endemic regions. To assist in malaria control efforts, a multi-component malaria control intervention was implemented in the hyperendemic region of Guéckédou Prefecture. The coverage of the intervention and its impact on malaria parasite prevalence were assessed. Five cross-sectional surveys using cluster-based sampling and stratified by area were conducted from 2011 to 2013 in three sous-préfectures of Guéckédou Préfecture that received the intervention: Guéckédou City, Tékoulo and Guendembou in addition to one comparison sous-préfecture that did not receive the intervention, Koundou. Surveys were repeated every 6 months, corresponding with the dry and rainy seasons. Rapid diagnostic tests (RDT) were used to diagnose malaria infection. In each selected household, bed net use and ownership were assessed. A total of 35,123 individuals participated in the surveys. Malaria parasite prevalence declined in all intervention sous-préfectures from 2011 to 2013 (56.4-45.9 % in Guéckédou City, 64.9-54.1 % in Tékoulo and 69.4-56.9 % in Guendembou) while increasing in the comparison sous-préfecture (64.5-69 %). It was consistently higher in children 5-14 years of age followed by those 1-59 months and ≥15 years. Indicators of intervention coverage, the proportion of households reporting ownership of at least one bed net and the proportion of survey participants with fever who received treatment from a health facility or community health worker also increased significantly in the intervention areas. Implementation of the multi-component malaria control intervention significantly reduced the prevalence of malaria in the sous-préfectures of intervention while also increasing the coverage of bed nets. However, malaria prevalence remains unacceptably high and disproportionately affects children <15 years of age. In such situations
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2012-01-01
Background Malaria case management is a key strategy for malaria control. Effective coverage of parasite-based malaria diagnosis (PMD) remains limited in malaria endemic countries. This study assessed the health system's capacity to absorb PMD at primary health care facilities in Uganda. Methods In a cross sectional survey, using multi-stage cluster sampling, lower level health facilities (LLHF) in 11 districts in Uganda were assessed for 1) tools, 2) skills, 3) staff and infrastructure, and 4) structures, systems and roles necessary for the implementing of PMD. Results Tools for PMD (microscopy and/or RDTs) were available at 30 (24%) of the 125 LLHF. All LLHF had patient registers and 15% had functional in-patient facilities. Three months’ long stock-out periods were reported for oral and parenteral quinine at 39% and 47% of LLHF respectively. Out of 131 health workers interviewed, 86 (66%) were nursing assistants; 56 (43%) had received on-job training on malaria case management and 47 (36%) had adequate knowledge in malaria case management. Overall, only 18% (131/730) Ministry of Health approved staff positions were filled by qualified personnel and 12% were recruited or transferred within six months preceding the survey. Of 186 patients that received referrals from LLHF, 130(70%) had received pre-referral anti-malarial drugs, none received pre-referral rectal artesunate and 35% had been referred due to poor response to antimalarial drugs. Conclusion Primary health care facilities had inadequate human and infrastructural capacity to effectively implement universal parasite-based malaria diagnosis. The priority capacity building needs identified were: 1) recruitment and retention of qualified staff, 2) comprehensive training of health workers in fever management, 3) malaria diagnosis quality control systems and 4) strengthening of supply chain, stock management and referral systems. PMID:22920954
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Advances in nanomedicines for malaria treatment.
Aditya, N P; Vathsala, P G; Vieira, V; Murthy, R S R; Souto, E B
2013-12-01
Malaria is an infectious disease that mainly affects children and pregnant women from tropical countries. The mortality rate of people infected with malaria per year is enormous and became a public health concern. The main factor that has contributed to the success of malaria proliferation is the increased number of drug resistant parasites. To counteract this trend, research has been done in nanotechnology and nanomedicine, for the development of new biocompatible systems capable of incorporating drugs, lowering the resistance progress, contributing for diagnosis, control and treatment of malaria by target delivery. In this review, we discussed the main problems associated with the spread of malaria and the most recent developments in nanomedicine for anti-malarial drug delivery. © 2013.
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The effect of dams and seasons on malaria incidence and anopheles abundance in Ethiopia
2013-01-01
Background Reservoirs created by damming rivers are often believed to increase malaria incidence risk and/or stretch the period of malaria transmission. In this paper, we report the effects of a mega hydropower dam on P. falciparum malaria incidence in Ethiopia. Methods A longitudinal cohort study was conducted over a period of 2 years to determine Plasmodium falciparum malaria incidence among children less than 10 years of age living near a mega hydropower dam in Ethiopia. A total of 2080 children from 16 villages located at different distances from a hydropower dam were followed up from 2008 to 2010 using active detection of cases based on weekly house to house visits. Of this cohort of children, 951 (48.09%) were females and 1059 (51.91%) were males, with a median age of 5 years. Malaria vectors were simultaneously surveyed in all the 16 study villages. Frailty models were used to explore associations between time-to-malaria and potential risk factors, whereas, mixed-effects Poisson regression models were used to assess the effect of different covariates on anopheline abundance. Results Overall, 548 (26.86%) children experienced at least one clinical malaria episode during the follow up period with mean incidence rate of 14.26 cases/1000 child-months at risk (95% CI: 12.16 - 16.36). P. falciparum malaria incidence showed no statistically significant association with distance from the dam reservoir (p = 0.32). However, P. falciparum incidence varied significantly between seasons (p < 0.01). The malaria vector, Anopheles arabiensis, was however more abundant in villages nearer to the dam reservoir. Conclusions P. falciparum malaria incidence dynamics were more influenced by seasonal drivers than by the dam reservoir itself. The findings could have implications in timing optimal malaria control interventions and in developing an early warning system in Ethiopia. PMID:23566411
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... Insecticide-Treated Nets (ITNs) Intermittent Preventive Treatment of Malaria in Pregnanct Women (IPTp) Indoor Residual Spraying (IRS) Vector Control Antimalarials to Reduce Transmission Vaccines Microscopy Rapid Diagnostic Tests Drug Resistance Counterfeit and ...
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Quantifying the impact of decay in bed-net efficacy on malaria transmission
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ngonghala, Calistus N.; Del Valle, Sara Y.; Zhao, Ruijun
Insecticide-treated nets (ITNs) are at the forefront of malaria control programs and even though the percentage of households in sub-Saharan Africa that owned nets increased from 3% in 2000 to 53% in 2012, many children continue to die from malaria. The potential impact of ITNs on reducing malaria transmission is limited due to inconsistent or improper use, as well as physical decay in effectiveness. Most mathematical models for malaria transmission have assumed a fixed effectiveness rate for bed-nets, which can overestimate the impact of nets on malaria control. We develop a model for malaria spread that captures the decrease inmore » ITN effectiveness due to physical and chemical decay, as well as human behavior as a function of time. We perform uncertainty and sensitivity analyses to identify and rank parameters that play a critical role in malaria transmission. These analyses show that the basic reproduction number R 0, and the infectious human population are most sensitive to bed-net coverage and the biting rate of mosquitoes. Our results show the existence of a backward bifurcation for the case in which ITN efficacy is constant over time, which occurs for some range of parameters and is characterized by high malaria mortality in humans. This result implies that bringing R 0 to less than one is not enough for malaria elimination but rather additional efforts will be necessary to control the disease. For the case in which ITN efficacy decays over time, we determine coverage levels required to control malaria for different ITN efficacies and demonstrate that ITNs with longer useful lifespans perform better in malaria control. We conclude that malaria control programs should focus on increasing bed-net coverage, which can be achieved by enhancing malaria education and increasing bed-net distribution in malaria endemic regions.« less
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Quantifying the impact of decay in bed-net efficacy on malaria transmission
Ngonghala, Calistus N.; Del Valle, Sara Y.; Zhao, Ruijun; ...
2014-08-23
Insecticide-treated nets (ITNs) are at the forefront of malaria control programs and even though the percentage of households in sub-Saharan Africa that owned nets increased from 3% in 2000 to 53% in 2012, many children continue to die from malaria. The potential impact of ITNs on reducing malaria transmission is limited due to inconsistent or improper use, as well as physical decay in effectiveness. Most mathematical models for malaria transmission have assumed a fixed effectiveness rate for bed-nets, which can overestimate the impact of nets on malaria control. We develop a model for malaria spread that captures the decrease inmore » ITN effectiveness due to physical and chemical decay, as well as human behavior as a function of time. We perform uncertainty and sensitivity analyses to identify and rank parameters that play a critical role in malaria transmission. These analyses show that the basic reproduction number R 0, and the infectious human population are most sensitive to bed-net coverage and the biting rate of mosquitoes. Our results show the existence of a backward bifurcation for the case in which ITN efficacy is constant over time, which occurs for some range of parameters and is characterized by high malaria mortality in humans. This result implies that bringing R 0 to less than one is not enough for malaria elimination but rather additional efforts will be necessary to control the disease. For the case in which ITN efficacy decays over time, we determine coverage levels required to control malaria for different ITN efficacies and demonstrate that ITNs with longer useful lifespans perform better in malaria control. We conclude that malaria control programs should focus on increasing bed-net coverage, which can be achieved by enhancing malaria education and increasing bed-net distribution in malaria endemic regions.« less
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Mitchell, Sara N; Catteruccia, Flaminia
2017-12-01
Vectorial capacity is a mathematical approximation of the efficiency of vector-borne disease transmission, measured as the number of new infections disseminated per case per day by an insect vector. Multiple elements of mosquito biology govern their vectorial capacity, including survival, population densities, feeding preferences, and vector competence. Intriguingly, biological pathways essential to mosquito reproductive fitness directly or indirectly influence a number of these elements. Here, we explore this complex interaction, focusing on how the interplay between mating and blood feeding in female Anopheles not only shapes their reproductive success but also influences their ability to sustain Plasmodium parasite development. Central to malaria transmission, mosquito reproductive biology has recently become the focus of research strategies aimed at malaria control, and we discuss promising new methods based on the manipulation of key reproductive steps. In light of widespread resistance to all public health-approved insecticides targeting mosquito reproduction may prove crucial to the success of malaria-eradication campaigns. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.
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Oral iron supplements for children in malaria-endemic areas
Neuberger, Ami; Okebe, Joseph; Yahav, Dafna; Paul, Mical
2016-01-01
Background Iron-deficiency anaemia is common during childhood. Iron administration has been claimed to increase the risk of malaria. Objectives To evaluate the effects and safety of iron supplementation, with or without folic acid, in children living in areas with hyperendemic or holoendemic malaria transmission. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library, MEDLINE (up to August 2015) and LILACS (up to February 2015). We also checked the metaRegister of Controlled Trials (mRCT) and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) up to February 2015. We contacted the primary investigators of all included trials, ongoing trials, and those awaiting assessment to ask for unpublished data and further trials. We scanned references of included trials, pertinent reviews, and previous meta-analyses for additional references. Selection criteria We included individually randomized controlled trials (RCTs) and cluster RCTs conducted in hyperendemic and holoendemic malaria regions or that reported on any malaria-related outcomes that included children younger than 18 years of age. We included trials that compared orally administered iron, iron with folic acid, and iron with antimalarial treatment versus placebo or no treatment. We included trials of iron supplementation or fortification interventions if they provided at least 80% of the Recommended Dietary Allowance (RDA) for prevention of anaemia by age. Antihelminthics could be administered to either group, and micronutrients had to be administered equally to both groups. Data collection and analysis The primary outcomes were clinical malaria, severe malaria, and death from any cause. We assessed the risk of bias in included trials with domain-based evaluation and assessed the quality of the evidence using the Grading of Recommendations Assessment
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Malaria transmission in Tripura: Disease distribution & determinants.
Dev, Vas; Adak, Tridibes; Singh, Om P; Nanda, Nutan; Baidya, Bimal K
2015-12-01
Malaria is a major public health problem in Tripura and focal disease outbreaks are of frequent occurrence. The state is co-endemic for both Plasmodium falciparum and P. vivax and transmission is perennial and persistent. The present study was aimed to review data on disease distribution to prioritize high-risk districts, and to study seasonal prevalence of disease vectors and their bionomical characteristics to help formulate vector species-specific interventions for malaria control. Data on malaria morbidity in the State were reviewed retrospectively (2008-2012) for understanding disease distribution and transmission dynamics. Cross-sectional mass blood surveys were conducted in malaria endemic villages of South Tripura district to ascertain the prevalence of malaria and proportions of parasite species. Mosquito collections were made in human dwellings of malaria endemic villages aiming at vector incrimination and to study relative abundance, resting and feeding preferences, and their present susceptibility status to DDT. The study showed that malaria was widely prevalent and P. falciparum was the predominant infection (>90%), the remaining were P. vivax cases. The disease distribution, however, was uneven with large concentration of cases in districts of South Tripura and Dhalai coinciding with vast forest cover and tribal populations. Both Anopheles minimus s.s. and An. baimaii were recorded to be prevalent and observed to be highly anthropophagic and susceptible to DDT. Of these, An. minimus was incriminated (sporozoite infection rate 4.92%), and its bionomical characteristics revealed this species to be largely indoor resting and endophagic. For effective control of malaria in the state, it is recommended that diseases surveillance should be robust, and vector control interventions including DDT spray coverage, mass distribution of insecticide-treated nets/ long-lasting insecticidal nets should be intensified prioritizing population groups most at risk to
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Hodson, C N; Yu, Y; Plettner, E; Roitberg, B D
2016-12-01
Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is a vector for Plasmodium, the causative agent of malaria. Current control strategies to reduce the impact of malaria focus on reducing the frequency of mosquito attacks on humans, thereby decreasing Plasmodium transmission. A need for new repellents effective against Anopheles mosquitoes has arisen because of changes in vector behaviour as a result of control strategies and concern over the health impacts of current repellents. The response of A. gambiae to potential repellents was investigated through an electroantennogram screen and the most promising of these candidates (1-allyloxy-4-propoxybenzene, 3c{3,6}) chosen for behavioural testing. An assay to evaluate the blood-host seeking behaviour of A. gambiae towards a simulated host protected with this repellent was then performed. The compound 3c{3,6} was shown to be an effective repellent, causing mosquitoes to reduce their contact with a simulated blood-host and probe less at the host odour. Thus, 3c{3,6} may be an effective repellent for the control of A. gambiae. © 2016 The Royal Entomological Society.
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Estimating the malaria risk of African mosquito movement by air travel
Tatem, Andrew J; Rogers, David J; Hay, Simon I
2006-01-01
Background The expansion of global travel has resulted in the importation of African Anopheles mosquitoes, giving rise to cases of local malaria transmission. Here, cases of 'airport malaria' are used to quantify, using a combination of global climate and air traffic volume, where and when are the greatest risks of a Plasmodium falciparum-carrying mosquito being importated by air. This prioritises areas at risk of further airport malaria and possible importation or reemergence of the disease. Methods Monthly data on climate at the World's major airports were combined with air traffic information and African malaria seasonality maps to identify, month-by-month, those existing and future air routes at greatest risk of African malaria-carrying mosquito importation and temporary establishment. Results The location and timing of recorded airport malaria cases proved predictable using a combination of climate and air traffic data. Extending the analysis beyond the current air network architecture enabled identification of the airports and months with greatest climatic similarity to P. falciparum endemic regions of Africa within their principal transmission seasons, and therefore at risk should new aviation routes become operational. Conclusion With the growth of long haul air travel from Africa, the identification of the seasonality and routes of mosquito importation is important in guiding effective aircraft disinsection and vector control. The recent and continued addition of air routes from Africa to more climatically similar regions than Europe will increase movement risks. The approach outlined here is capable of identifying when and where these risks are greatest. PMID:16842613
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Lessons learnt from the first controlled human malaria infection study conducted in Nairobi, Kenya.
Hodgson, Susanne H; Juma, Elizabeth; Salim, Amina; Magiri, Charles; Njenga, Daniel; Molyneux, Sassy; Njuguna, Patricia; Awuondo, Ken; Lowe, Brett; Billingsley, Peter F; Cole, Andrew O; Ogwang, Caroline; Osier, Faith; Chilengi, Roma; Hoffman, Stephen L; Draper, Simon J; Ogutu, Bernhards; Marsh, Kevin
2015-04-28
Controlled human malaria infection (CHMI) studies, in which healthy volunteers are infected with Plasmodium falciparum to assess the efficacy of novel malaria vaccines and drugs, have become a vital tool to accelerate vaccine and drug development. CHMI studies provide a cost-effective and expeditious way to circumvent the use of large-scale field efficacy studies to deselect intervention candidates. However, to date few modern CHMI studies have been performed in malaria-endemic countries. An open-label, randomized pilot CHMI study was conducted using aseptic, purified, cryopreserved, infectious P. falciparum sporozoites (SPZ) (Sanaria® PfSPZ Challenge) administered intramuscularly (IM) to healthy Kenyan adults (n = 28) with varying degrees of prior exposure to P. falciparum. The purpose of the study was to establish the PfSPZ Challenge CHMI model in a Kenyan setting with the aim of increasing the international capacity for efficacy testing of malaria vaccines and drugs, and allowing earlier assessment of efficacy in a population for which interventions are being developed. This was part of the EDCTP-funded capacity development of the CHMI platform in Africa. This paper discusses in detail lessons learnt from conducting the first CHMI study in Kenya. Issues pertinent to the African setting, including community sensitization, consent and recruitment are considered. Detailed reasoning regarding the study design (for example, dose and route of administration of PfSPZ Challenge, criteria for grouping volunteers according to prior exposure to malaria and duration of follow-up post CHMI) are given and changes other centres may want to consider for future studies are suggested. Performing CHMI studies in an African setting presents unique but surmountable challenges and offers great opportunity for acceleration of malaria vaccine and drug development. The reflections in this paper aim to aid other centres and partners intending to use the CHMI model in Africa.
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Current management and prevention of malaria in pregnancy: a review.
Agboghoroma, C O
2014-01-01
Pregnant women suffer more frequent and severe malaria than non-pregnant women. Malaria in pregnancy contributes to the high maternal and perinatal morbidity and mortality in Africa. To review the burden and highlight the current management and prevention strategies for control of malaria in pregnancy in Africa. Papers for this review were identified by searches of PubMed and Google, and references from relevant articles. Search terms were "malaria", "malaria in pregnancy", "Malaria during pregnancy" and "antimalarial drug". Only papers published in English between 1983 and 2013 were included. In malarial endemic areas, acquired partial malarial immunity is not effective during pregnancy. Pregnant women are prone to frequent malaria infections which may be severe or asymptomatic but associated with placental parasitization. Malaria contributes 2-15% to maternal anaemia, 13-70% to intrauterine growth restriction, 8-14% to low birth weight, 8-36% to prematurity, 3-8% to infant deaths and 2.9-17.6% to maternal mortality. The control of malaria in pregnancy is currently predicated on three main strategies: 1) Prompt and effective case management of malaria; 2).Use of Insecticide-treated nets; and 3).Intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine. Artemisinin-based combined therapy is the recommended treatment for uncomplicated malaria in the second and third trimesters of pregnancy, while quinine is used in the first trimester and for severe cases of malaria at any gestational age. The control of malaria during pregnancy should be an integral part of efforts to reduce maternal and perinatal morbidity and mortality in Africa.
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2012-01-01
Background Children are most vulnerable to malaria. A pyronaridine-artesunate pediatric granule formulation is being developed for the treatment of uncomplicated Plasmodium falciparum malaria. Methods This phase III, multi-center, comparative, open-label, parallel-group, controlled clinical trial included patients aged ≤12 years, bodyweight ≥5 to <25 kg, with a reported history of fever at inclusion or in the previous 24 h and microscopically-confirmed uncomplicated P. falciparum malaria. Patients were randomized (2:1) to pyronaridine-artesunate granules (60/20 mg) once daily or artemether-lumefantrine crushed tablets (20/120 mg) twice daily, both dosed by bodyweight, orally (liquid suspension) for three days. Results Of 535 patients randomized, 355 received pyronaridine-artesunate and 180 received artemether-lumefantrine. Day-28 adequate clinical and parasitological response (ACPR), corrected for re-infection using polymerase chain reaction (PCR) genotyping (per-protocol population) was 97.1% (329/339; 95% CI 94.6, 98.6) for pyronaridine-artesunate; 98.8% (165/167; 95% CI 95.7, 99.9) for artemether-lumefantrine. The primary endpoint was achieved: pyronaridine-artesunate PCR-corrected day-28 ACPR was statistically significantly >90% (P < .0001). Pyronaridine-artesunate was non-inferior to artemether-lumefantrine: treatment difference -1.8% (95% CI -4.3 to 1.6). The incidence of drug-related adverse events was 37.2% (132/355) with pyronaridine-artesunate, 44.4% (80/180) with artemether-lumefantrine. Clinical biochemistry results showed similar mean changes versus baseline in the two treatment groups. From day 3 until study completion, one patient in each treatment group had peak alanine aminotransferase (ALT) >3 times the upper limit of normal (ULN) and peak total bilirubin >2xULN (i.e. within the Hy’s law definition). Conclusions The pyronaridine-artesunate pediatric granule formulation was efficacious and was non-inferior to artemether-lumefantrine. The
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Effective Program Management: A Cornerstone of Malaria Elimination
Gosling, Jonathan; Case, Peter; Tulloch, Jim; Chandramohan, Daniel; Wegbreit, Jennifer; Newby, Gretchen; Gueye, Cara Smith; Koita, Kadiatou; Gosling, Roly
2015-01-01
Effective program management is essential for successful elimination of malaria. In this perspective article, evidence surrounding malaria program management is reviewed by management science and malaria experts through a literature search of published and unpublished gray documents and key informant interviews. Program management in a malaria elimination setting differs from that in a malaria control setting in a number of ways, although knowledge and understanding of these distinctions are lacking. Several core features of successful health program management are critical to achieve elimination, including effective leadership and supervision at all levels, sustained political and financial commitment, reliable supply and control of physical resources, effective management of data and information, appropriate incentives, and consistent accountability. Adding to the complexity, the requirements of an elimination program may conflict with those of a control regimen. Thus, an additional challenge is successfully managing program transitions along the continuum from control to elimination to prevention of reintroduction. This article identifies potential solutions to these challenges by exploring managerial approaches that are flexible, relevant, and sustainable in various cultural and health system contexts. PMID:26013372
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Magris, M; Rubio-Palis, Y; Alexander, N; Ruiz, B; Galván, N; Frias, D; Blanco, M; Lines, J
2007-03-01
We conducted a community-randomized controlled trial in an area of moderate malaria transmission in the Amazon region, southern Venezuela, home of the Yanomami indigenous ethnic group. The aim was to compare the malaria incidence rate in villages with lambdacyhalothrin-treated hammock nets (ITHN) or with placebo-treated hammock nets (PTHN). In both arms of the study, intensive surveillance for early case detection was maintained and prompt malaria treatment was administered. Baseline data were collected before the intervention and a population of around 924 Yanomami was followed for 2 years. Despite the recent introduction of nets in the Yanomami villages and the adverse natural conditions in the area, the nets were accepted enthusiastically by the study population, used conscientiously and looked after carefully. The malaria incidence rate per thousand person-years at risk was 114.6 in the IHTN group and 186.8 in the PTHN group. The adjusted rate ratios indicated that ITHN prevent 56% [IRR: 0.44, 95% confidence interval (CI): 52-59%] of new malaria cases. ITHN reduced the prevalence of parasitaemia by 83% [relative risks (RR): 0.17, 95% CI: 47-100%], according to a cross-sectional survey carried out during the high transmission season. The prevalence of splenomegaly and anaemia was too low to detect any possible reduction as a result of ITHN. The main conclusion of the present study is that ITHN can reduce malaria incidence in the area and it is the most feasible method for malaria control in a forested area where indigenous villages are scattered over a large territory. This is the first community-level epidemiological trial to show that ITHN are highly effective against malaria transmitted by Anopheles darlingi.
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Alba, Sandra; Nathan, Rose; Schulze, Alexander; Mshinda, Hassan; Lengeler, Christian
2014-02-01
Between 1997 and 2009, a number of key malaria control interventions were implemented in the Kilombero and Ulanga Districts in south central Tanzania to increase insecticide-treated nets (ITN) coverage and improve access to effective malaria treatment. In this study we estimated the contribution of these interventions to observed decreases in child mortality. The local Health and Demographic Surveillance Site (HDSS) provided monthly estimates of child mortality rates (age 1 to 5 years) expressed as cases per 1000 person-years (c/1000py) between 1997 and 2009. We conducted a time series analysis of child mortality rates and explored the contribution of rainfall and household food security. We used Poisson regression with linear and segmented effects to explore the impact of malaria control interventions on mortality. Child mortality rates decreased by 42.5% from 14.6 c/1000py in 1997 to 8.4 c/1000py in 2009. Analyses revealed the complexity of child mortality patterns and a strong association with rainfall and food security. All malaria control interventions were associated with decreases in child mortality, accounting for the effect of rainfall and food security. Reaching the fourth Millenium Development Goal will require the contribution of many health interventions, as well as more general improvements in socio-environmental and nutritional conditions. Distinguishing between the effects of these multiple factors is difficult and represents a major challenge in assessing the effect of routine interventions. However, this study suggests that credible estimates can be obtained when high-quality data on the most important factors are available over a sufficiently long time period.
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Parobek, Christian M.; Lin, Jessica T.; Saunders, David L.; Barnett, Eric J.; Lon, Chanthap; Lanteri, Charlotte A.; Balasubramanian, Sujata; Brazeau, Nicholas; DeConti, Derrick K.; Garba, Deen L.; Meshnick, Steven R.; Spring, Michele D.; Chuor, Char Meng; Bailey, Jeffrey A.; Juliano, Jonathan J.
2016-01-01
Cambodia, in which both Plasmodium vivax and Plasmodium falciparum are endemic, has been the focus of numerous malaria-control interventions, resulting in a marked decline in overall malaria incidence. Despite this decline, the number of P. vivax cases has actually increased. To understand better the factors underlying this resilience, we compared the genetic responses of the two species to recent selective pressures. We sequenced and studied the genomes of 70 P. vivax and 80 P. falciparum isolates collected between 2009 and 2013. We found that although P. falciparum has undergone population fracturing, the coendemic P. vivax population has grown undisrupted, resulting in a larger effective population size, no discernable population structure, and frequent multiclonal infections. Signatures of selection suggest recent, species-specific evolutionary differences. Particularly, in contrast to P. falciparum, P. vivax transcription factors, chromatin modifiers, and histone deacetylases have undergone strong directional selection, including a particularly strong selective sweep at an AP2 transcription factor. Together, our findings point to different population-level adaptive mechanisms used by P. vivax and P. falciparum parasites. Although population substructuring in P. falciparum has resulted in clonal outgrowths of resistant parasites, P. vivax may use a nuanced transcriptional regulatory approach to population maintenance, enabling it to preserve a larger, more diverse population better suited to facing selective threats. We conclude that transcriptional control may underlie P. vivax’s resilience to malaria control measures. Novel strategies to target such processes are likely required to eradicate P. vivax and achieve malaria elimination. PMID:27911780
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Koita, Kadiatou; Novotny, Joseph; Kunene, Simon; Zulu, Zulizile; Ntshalintshali, Nyasatu; Gandhi, Monica; Gosling, Roland
2013-06-27
Swaziland has made great progress towards its goal of malaria elimination by 2015. However, malaria importation from neighbouring high-endemic Mozambique through Swaziland's eastern border remains a major factor that could prevent elimination from being achieved. In order to reach elimination, Swaziland must rapidly identify and treat imported malaria cases before onward transmission occurs. A nationwide formative assessment was conducted over eight weeks to determine if the imported cases of malaria identified by the Swaziland National Malaria Control Programme could be linked to broader social networks and to explore methods to access these networks. Using a structured format, interviews were carried out with malaria surveillance agents (6), health providers (10), previously identified imported malaria cases (19) and people belonging to the networks identified through these interviews (25). Most imported malaria cases were Mozambicans (63%, 12/19) making a living in Swaziland and sustaining their families in Mozambique. The majority of imported cases (73%, 14/19) were labourers and self-employed contractors who travelled frequently to Mozambique to visit their families and conduct business. Social networks of imported cases with similar travel patterns were identified through these interviews. Nearly all imported cases (89%, 17/19) were willing to share contact information to enable network members to be interviewed. Interviews of network members and key informants revealed common congregation points, such as the urban market places in Manzini and Malkerns, as well as certain bus stations, where people with similar travel patterns and malaria risk behaviours could be located and tested for malaria. This study demonstrated that imported cases of malaria belonged to networks of people with similar travel patterns. This study may provide novel methods for screening high-risk groups of travellers using both snowball sampling and time-location sampling of networks to
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The economic benefits of malaria elimination: do they include increases in tourism?
2012-01-01
Background Policy makers have speculated that one of the economic benefits of malaria elimination includes increases in foreign direct investment, particularly tourism. Methods This study examines the empirical relationship between the demand for travel and malaria cases in two countries with large tourism industries around the time in which they carried out malaria-elimination campaigns. In Mauritius, this analysis examines historical, yearly tourist arrivals and malaria cases from 1978–1999, accounting for the background secular trend of increasing international travel. In Dominican Republic, a country embarking upon malaria elimination, it employs a time-series analysis of the monthly, international tourist arrivals from 1998–2010 to determine whether the timing of significant deviations in tourist arrivals coincides with malaria outbreaks. Results While naïve relationships exist in both cases, the results show that the relationships between tourist arrivals and malaria cases are relatively weak and statistically insignificant once secular confounders are accounted for. Conclusions This suggests that any economic benefits from tourism that may be derived from actively pursuing elimination in countries that have high tourism potential are likely to be small when measured at a national level. Rather, tourism benefits are likely to be experienced with greater impact in more concentrated tourist areas within countries, and future studies should seek to assess these relationships at a regional or local level. PMID:22839351
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PIRAHMADI, Sakineh; ZAKERI, Sedigheh; RAEISI, Ahmad
2017-01-01
Background: Asymptomatic malaria infection provides a reservoir of parasites, causing the persistence of malaria transmission. It accounts an important challenge for successful management of the control, elimination, and eradication programmes in any malaria-endemic region. This investigation was designed to assess the presence and the prevalence of asymptomatic carriers in Iranshahr district of Sistan and Baluchistan Province (2013–2014), with a considerable population movement, during the malaria elimination phase in Iran. Methods: Finger-prick blood samples were collected from symptomless (n=250) and febrile (n=50) individuals residing in Iranshahr district, easthern Iran (Hoodian, Mand, Chah-e Giji, Jolgehashem, Esfand, Dalgan and Chahshour) during Jan 2013 to Dec 2014, and Plasmodium infections were detected using light microscopic and highly sensitive nested-PCR techniques. Results: Thick and thin Giemsa-stained blood smears were negative for Plasmodium parasites. In addition, based on nested-PCR analysis, no P. vivax, P. falciparum, and P. malariae parasites were detected among the studied individuals. Conclusion: Investigation the absence of asymptomatic carriers in Iranshahr district was illustrated and achieving malaria elimination in this area is feasible in a near future. PMID:28761465
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Heng, Somony; Sluydts, Vincent; Durnez, Lies; Mean, Vanna; Polo, Koh; Tho, Sochantha; Coosemans, Marc; van Griensven, Johan
2017-01-01
Background While community distribution of topical repellents has been proposed as an additional malaria control intervention, the safety of this intervention at the population level remains poorly evaluated. We describe the safety of mass distribution of the picaridin repellent during a cluster-randomised trial in rural Cambodia in 2012–2013. Methods The repellent was distributed among 57 intervention villages with around 25,000 inhabitants by a team of village distributors. Information on individual adverse events, reported by phone by the village distributors, was obtained through home visits. Information on perceived side effects, reported at the family level, was obtained during two-weekly bottle exchange. Adverse events were classified as adverse reactions (events likely linked to the repellent), cases of repellent abuse and events not related to the repellent use, and classified as per Common Terminology Criteria for Adverse Events. Findings Of the 41 adverse events notified by phone by the village distributors, there were 22 adverse reactions, 11 cases of repellent abuse (6 accidental, 5 suicide attempts) and 8 non-related events. All adverse reactions were mild, occurred in the first few months of use, and mainly manifested as skin conditions. Of the 11 cases of abuse, 2 were moderate and 2 life-threatening. All cases with adverse reactions and repellent abuse recovered completely. 20% of families reported perceived side effects, mainly itching, headache, dizziness and bad smell, but few discontinued repellent use. Conclusions Adverse reactions and abuse during mass use of picaridin were uncommon and generally mild, supporting the safety of the picaridin repellent for malaria control. PMID:28339462
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2010-01-01
Background Given that helminth infections are thought to have strong immunomodulatory activity, the question whether helminth infections might affect responses to malaria antigens needs to be addressed. Different cross-sectional studies using diverse methodologies have reported that helminth infections might either exacerbate or reduce the severity of malaria attacks. The same discrepancies have been reported for parasitemia. Methods/Design To determine the effect of geohelminth infections and their treatment on malaria infection and disease outcome, as well as on immunological parameters, the area of Nangapanda on Flores Island, Indonesia, where malaria and helminth parasites are co-endemic was selected for a longitudinal study. Here a Double-blind randomized trial will be performed, incorporating repeated treatment with albendazole (400 mg) or placebo at three monthly intervals. Household characteristic data, anthropometry, the presence of intestinal helminth and Plasmodium spp infections, and the incidence of malaria episodes are recorded. In vitro cultures of whole blood, stimulated with a number of antigens, mitogens and toll like receptor ligands provide relevant immunological parameters at baseline and following 1 and 2 years of treatment rounds. The primary outcome of the study is the prevalence of Plasmodium falciparum and P. vivax infection. The secondary outcome will be incidence and severity of malaria episodes detected via both passive and active follow-up. The tertiary outcome is the inflammatory cytokine profile in response to parasite antigens. The project also facilitates the transfer of state of the art methodologies and technologies, molecular diagnosis of parasitic diseases, immunology and epidemiology from Europe to Indonesia. Discussion The study will provide data on the effect of helminth infections on malaria. It will also give information on anthelminthic treatment efficacy and effectiveness and could help develop evidence
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Velarde-Rodríguez, Mar; Van den Bergh, Rafael; Fergus, Cristin; Casellas, Aina; Sanz, Sergi; Cibulskis, Richard; Ramsay, Andrew R.; Bissell, Karen; Zachariah, Rony
2015-01-01
Background Countries in the different stages of pre-elimination, elimination, and prevention of reintroduction are required to report the number of indigenous and imported malaria cases to the World Health Organization (WHO). However, these data have not been systematically analysed at the global level. Objective For the period 2007 to 2013, we aimed to report on 1) the proportion of countries providing data on the origin of malaria cases and 2) the origin of malaria cases in countries classified as being in the stages of pre-elimination, elimination and prevention of reintroduction. Design An observational study using annual data reported through routine health information systems to the WHO Global Malaria Programme between 2007 and 2013. Results For all countries classified as being in pre-elimination, elimination, and prevention of reintroduction in the year 2013, there has been a substantial decrease in the total number of indigenous malaria cases, from more than 15,000 cases reported in 2007 to less than 4,000 cases reported in 2013. However, the total number of imported malaria cases has increased over that time period, from 5,600 imported cases in 2007 to approximately 6,800 in 2013. Conclusions Vigilant monitoring of the numbers of imported and indigenous malaria cases at national and global levels as well as appropriate strategies to target these cases will be critical to achieve malaria eradication. PMID:26449205
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Malaria prevalence in Nias District, North Sumatra Province, Indonesia
Syafruddin, Din; Asih, Puji BS; Wahid, Isra; Dewi, Rita M; Tuti, Sekar; Laowo, Idaman; Hulu, Waozidohu; Zendrato, Pardamean; Laihad, Ferdinand; Shankar, Anuraj H
2007-01-01
Background The Nias district of the North Sumatra Province of Indonesia has long been known to be endemic for malaria. Following the economic crisis at the end of 1998 and the subsequent tsunami and earthquake, in December 2004 and March 2005, respectively, the malaria control programme in the area deteriorated. The present study aims to provide baseline data for the establishment of a suitable malaria control programme in the area and to analyse the frequency distribution of drug resistance alleles associated with resistance to chloroquine and sulphadoxine-pyrimethamine. Methods Malariometric and entomology surveys were performed in three subdistricts. Thin and thick blood smears were stained with Giemsa and examined under binocular light microscopy. Blood blots on filter paper were also prepared for isolation of parasite and host DNA to be used for molecular analysis of band 3 (SAO), pfcrt, pfmdr1, dhfr, and dhps. In addition, haemoglobin measurement was performed in the second and third surveys for the subjects less than 10 years old. Results Results of the three surveys revealed an average slide positivity rate of 8.13%, with a relatively higher rate in certain foci. Host genetic analysis, to identify the Band 3 deletion associated with Southeast Asian Ovalocytosis (SAO), revealed an overall frequency of 1.0% among the 1,484 samples examined. One hundred six Plasmodium falciparum isolates from three sub-districts were successfully analysed. Alleles of the dhfr and dhps genes associated with resistance to sulphadoxine-pyrimethamine, dhfr C59R and S108N, and dhps A437G and K540E, were present at frequencies of 52.2%, 82.5%, 1.18% and 1.18%, respectively. The pfmdr1 alleles N86Y and N1042D, putatively associated with mefloquine resistance, were present at 31.4% and 2%, respectively. All but one sample carried the pfcrt 76T allele associated with chloroquine resistance. Entomologic surveys identified three potential anopheline vectors in the area, Anopheles
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Yakob, Laith; Cameron, Mary; Lines, Jo
2017-03-13
Malaria is spread by mosquitoes that are increasingly recognised to have diverse biting behaviours. How a mosquito in a specific environment responds to differing availability of blood-host species is largely unknown and yet critical to vector control efficacy. A parsimonious mathematical model is proposed that accounts for a diverse range of host-biting behaviours and assesses their impact on combining long-lasting insecticidal nets (LLINs) with a novel approach to malaria control: livestock treated with insecticidal compounds ('endectocides') that kill biting mosquitoes. Simulations of a malaria control programme showed marked differences across biting ecologies in the efficacy of both LLINs as a stand-alone tool and the combination of LLINs with endectocide-treated cattle. During the intervals between LLIN mass campaigns, concordant use of endectocides is projected to reduce the bounce-back in malaria prevalence that can occur as LLIN efficacy decays over time, especially if replacement campaigns are delayed. Integrating these approaches can also dramatically improve the attainability of local elimination; endectocidal treatment schedules required to achieve this aim are provided for malaria vectors with different biting ecologies. Targeting blood-feeding mosquitoes by treating livestock with endectocides offers a potentially useful complement to existing malaria control programmes centred on LLIN distribution. This approach is likely to be effective against vectors with a wide range of host-preferences and biting behaviours, with the exception of species that are so strictly anthropophilic that most blood meals are taken on humans even when humans are much less available than non-human hosts. Identifying this functional relationship in wild mosquito populations and ascertaining the extent to which it differs, within as well as between species, is a critical next step before targets can be set for employing this novel approach and combination.
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[Malaria in Guiana. II. The characteristics of different foci and antimalarial control].
Mouchet, J; Nadire-Galliot, M; Gay, F; Poman, J P; Lepelletier, L; Claustre, J; Bellony, S
1989-01-01
In French Guiana, the distribution of malaria in foci inhabited by quite different ethnic groups calls for specific studies. Along the Oyapock on the Brasilian border and along the Litani on the Surinam border, incidence among American Indians and Creoles ranges from 300 and 900 per thousand; Plasmodium falciparum accounts for 65% and P. vivax for 35%. Along the middle and lower Maroni on the Surinam border, the Boni and Ndjukas Negroes move freely through the frontier and since the civil strife Surinamese used to attend health centres of Guiana. Therefore it is difficult to find the sources of contamination and the incidence among French citizens; P. falciparum is the only parasite recorded in this focus. In 1987 a small outbreak mainly due to P. vivax, occurred in a Lao refugees village in the hinterland. The coastal foci harbour large communities of Haitian and Brazilian migrants. The vector is Anopheles darlingi and up to now there is no evidence that other species could be involved. The rise of malaria despite of control measures involves several factors: the house spraying is no more accepted by a large percentage of house holders and the alternative larviciding has only a limited efficacy; the houses of American Indians have no walls to be sprayed; there is a continuous introduction of parasites by migrants. It has been said that vectors have change their behaviour toward exophily but such a statement has not yet been supported by evidence. All these factors should be taken in account to improve malaria control.
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Castro, Marcia C; Tsuruta, Atsuko; Kanamori, Shogo; Kannady, Khadija; Mkude, Sixbert
2009-04-08
Historically, environmental management has brought important achievements in malaria control and overall improvements of health conditions. Currently, however, implementation is often considered not to be cost-effective. A community-based environmental management for malaria control was conducted in Dar es Salaam between 2005 and 2007. After community sensitization, two drains were cleaned followed by maintenance. This paper assessed the impact of the intervention on community awareness, prevalence of malaria infection, and Anopheles larval presence in drains. A survey was conducted in neighbourhoods adjacent to cleaned drains; for comparison, neighbourhoods adjacent to two drains treated with larvicides and two drains under no intervention were also surveyed. Data routinely collected by the Urban Malaria Control Programme were also used. Diverse impacts were evaluated through comparison of means, odds ratios (OR), logistic regression, and time trends calculated by moving averages. Individual awareness of health risks and intervention goals were significantly higher among sensitized neighbourhoods. A reduction in the odds of malaria infection during the post-cleaning period in intervention neighbourhoods was observed when compared to the pre-cleaning period (OR = 0.12, 95% CI 0.05-0.3, p < 0.001). During the post-cleaning period, a higher risk of infection (OR = 1.7, 95% CI 1.1-2.4, p = 0.0069) was observed in neighbourhoods under no intervention compared to intervention ones. Eighteen months after the initial cleaning, one of the drains was still clean due to continued maintenance efforts (it contained no waste materials and the water was flowing at normal velocity). A three-month moving average of the percentage of water habitats in that drain containing pupae and/or Anopheles larvae indicated a decline in larval density. In the other drain, lack of proper resources and local commitment limited success. Although environmental management was historically
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Prevention and control of malaria in pregnancy - new threats, new opportunities?
Rogerson, Stephen J; Unger, Holger W
2017-04-01
Over 100 million women and their babies are at risk of malaria in pregnancy each year. Malaria prevention in pregnancy relies on long-lasting insecticidal nets (LLINs), and, in Africa, intermittent preventive treatment in pregnancy (IPTp). Increasing resistance of malaria parasites to sulfadoxine-pyrimethamine, the only drug endorsed for IPTp, and increasing mosquito resistance to pyrethroids used in LLINs, threaten the efficacy of these proven strategies, while operational challenges restrict their implementation in areas of great need. Areas Covered: This review summarizes strategies for malaria prevention in pregnancy (both currently used and those undergoing preclinical and clinical evaluation), primarily drawing on publications and study protocols from the last decade. Challenges associated with each strategy are discussed, including the particular problem of HIV and malaria in pregnancy, and areas of further research are highlighted. Expert Commentary: Alternative drugs for IPTp are needed. Dihydroartemisinin-piperaquine is particularly promising, but requires further evaluation, and might contribute to artemisinin resistance. Intermittent screening and treatment in pregnancy (ISTp) is an alternative to IPTp that could reduce unnecessary antenatal drug exposure and resistance risk, but it is not recommended with current, insensitive screening tests. Optimal strategies for areas of low or declining malaria transmission remain to be determined.
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Coulibaly, Drissa; Travassos, Mark A; Tolo, Youssouf; Laurens, Matthew B; Kone, Abdoulaye K; Traore, Karim; Sissoko, Mody; Niangaly, Amadou; Diarra, Issa; Daou, Modibo; Guindo, Boureima; Rebaudet, Stanislas; Kouriba, Bourema; Dessay, Nadine; Piarroux, Renaud; Plowe, Christopher V; Doumbo, Ogobara K; Thera, Mahamadou A; Gaudart, Jean
2017-12-01
In areas of seasonal malaria transmission, the incidence rate of malaria infection is presumed to be near zero at the end of the dry season. Asymptomatic individuals may constitute a major parasite reservoir during this time. We conducted a longitudinal analysis of the spatio-temporal distribution of clinical malaria and asymptomatic parasitemia over time in a Malian town to highlight these malaria transmission dynamics. For a cohort of 300 rural children followed over 2009-2014, periodicity and phase shift between malaria and rainfall were determined by spectral analysis. Spatial risk clusters of clinical episodes or carriage were identified. A nested-case-control study was conducted to assess the parasite carriage factors. Malaria infection persisted over the entire year with seasonal peaks. High transmission periods began 2-3 months after the rains began. A cluster with a low risk of clinical malaria in the town center persisted in high and low transmission periods. Throughout 2009-2014, cluster locations did not vary from year to year. Asymptomatic and gametocyte carriage were persistent, even during low transmission periods. For high transmission periods, the ratio of asymptomatic to clinical cases was approximately 0.5, but was five times higher during low transmission periods. Clinical episodes at previous high transmission periods were a protective factor for asymptomatic carriage, but carrying parasites without symptoms at a previous high transmission period was a risk factor for asymptomatic carriage. Stable malaria transmission was associated with sustained asymptomatic carriage during dry seasons. Control strategies should target persistent low-level parasitemia clusters to interrupt transmission.
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Climate change and the global malaria recession.
Gething, Peter W; Smith, David L; Patil, Anand P; Tatem, Andrew J; Snow, Robert W; Hay, Simon I
2010-05-20
The current and potential future impact of climate change on malaria is of major public health interest. The proposed effects of rising global temperatures on the future spread and intensification of the disease, and on existing malaria morbidity and mortality rates, substantively influence global health policy. The contemporary spatial limits of Plasmodium falciparum malaria and its endemicity within this range, when compared with comparable historical maps, offer unique insights into the changing global epidemiology of malaria over the last century. It has long been known that the range of malaria has contracted through a century of economic development and disease control. Here, for the first time, we quantify this contraction and the global decreases in malaria endemicity since approximately 1900. We compare the magnitude of these changes to the size of effects on malaria endemicity proposed under future climate scenarios and associated with widely used public health interventions. Our findings have two key and often ignored implications with respect to climate change and malaria. First, widespread claims that rising mean temperatures have already led to increases in worldwide malaria morbidity and mortality are largely at odds with observed decreasing global trends in both its endemicity and geographic extent. Second, the proposed future effects of rising temperatures on endemicity are at least one order of magnitude smaller than changes observed since about 1900 and up to two orders of magnitude smaller than those that can be achieved by the effective scale-up of key control measures. Predictions of an intensification of malaria in a warmer world, based on extrapolated empirical relationships or biological mechanisms, must be set against a context of a century of warming that has seen marked global declines in the disease and a substantial weakening of the global correlation between malaria endemicity and climate.
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Is outdoor vector control needed for malaria elimination? An individual-based modelling study.
Zhu, Lin; Müller, Günter C; Marshall, John M; Arheart, Kristopher L; Qualls, Whitney A; Hlaing, WayWay M; Schlein, Yosef; Traore, Sekou F; Doumbia, Seydou; Beier, John C
2017-07-03
Residual malaria transmission has been reported in many areas even with adequate indoor vector control coverage, such as long-lasting insecticidal nets (LLINs). The increased insecticide resistance in Anopheles mosquitoes has resulted in reduced efficacy of the widely used indoor tools and has been linked with an increase in outdoor malaria transmission. There are considerations of incorporating outdoor interventions into integrated vector management (IVM) to achieve malaria elimination; however, more information on the combination of tools for effective control is needed to determine their utilization. A spatial individual-based model was modified to simulate the environment and malaria transmission activities in a hypothetical, isolated African village setting. LLINs and outdoor attractive toxic sugar bait (ATSB) stations were used as examples of indoor and outdoor interventions, respectively. Different interventions and lengths of efficacy periods were tested. Simulations continued for 420 days, and each simulation scenario was repeated 50 times. Mosquito populations, entomologic inoculation rates (EIRs), probabilities of local mosquito extinction, and proportion of time when the annual EIR was reduced below one were compared between different intervention types and efficacy periods. In the village setting with clustered houses, the combinational intervention of 50% LLINs plus outdoor ATSBs significantly reduced mosquito population and EIR in short term, increased the probability of local mosquito extinction, and increased the time when annual EIR is less than one per person compared to 50% LLINs alone; outdoor ATSBs alone significantly reduced mosquito population in short term, increased the probability of mosquito extinction, and increased the time when annual EIR is less than one compared to 50% LLINs alone, but there was no significant difference in EIR in short term between 50% LLINs and outdoor ATSBs. In the village setting with dispersed houses, the
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A sticky situation: the unexpected stability of malaria elimination
Smith, David L.; Cohen, Justin M.; Chiyaka, Christinah; Johnston, Geoffrey; Gething, Peter W.; Gosling, Roly; Buckee, Caroline O.; Laxminarayan, Ramanan; Hay, Simon I.; Tatem, Andrew J.
2013-01-01
Malaria eradication involves eliminating malaria from every country where transmission occurs. Current theory suggests that the post-elimination challenges of remaining malaria-free by stopping transmission from imported malaria will have onerous operational and financial requirements. Although resurgent malaria has occurred in a majority of countries that tried but failed to eliminate malaria, a review of resurgence in countries that successfully eliminated finds only four such failures out of 50 successful programmes. Data documenting malaria importation and onwards transmission in these countries suggests malaria transmission potential has declined by more than 50-fold (i.e. more than 98%) since before elimination. These outcomes suggest that elimination is a surprisingly stable state. Elimination's ‘stickiness’ must be explained either by eliminating countries starting off qualitatively different from non-eliminating countries or becoming different once elimination was achieved. Countries that successfully eliminated were wealthier and had lower baseline endemicity than those that were unsuccessful, but our analysis shows that those same variables were at best incomplete predictors of the patterns of resurgence. Stability is reinforced by the loss of immunity to disease and by the health system's increasing capacity to control malaria transmission after elimination through routine treatment of cases with antimalarial drugs supplemented by malaria outbreak control. Human travel patterns reinforce these patterns; as malaria recedes, fewer people carry malaria from remote endemic areas to remote areas where transmission potential remains high. Establishment of an international resource with backup capacity to control large outbreaks can make elimination stickier, increase the incentives for countries to eliminate, and ensure steady progress towards global eradication. Although available evidence supports malaria elimination's stickiness at moderate
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Acceptance of a malaria vaccine by caregivers of sick children in Kenya
2014-01-01
Background Several malaria vaccines are currently in clinical trials and are expected to provide an improved strategy for malaria control. Prior to introduction of a new vaccine, policymakers must consider the socio cultural environment of the region to ensure widespread community approval. This study investigated the acceptance of a malaria vaccine by child caregivers and analysed factors that influence these. Methods Interviews from a standard questionnaire were conducted with 2,003 caregivers at 695 randomly selected health facilities across Kenya during the Kenya Service Provision Assessment Survey 2010. Multinomial regression of quantitative data was conducted using STATA to analyse determinants of caregivers accepting malaria vaccination of their child. Results Mothers represented 90% of caregivers interviewed who brought their child to the health facility, and 77% of caregivers were 20-34 years old. Overall, 88% of respondents indicated that they would accept a malaria vaccine, both for a child in their community and their own child. Approval for a vaccine was highest in malaria-endemic Nyanza Province at 98.9%, and lowest in the seasonal transmission area of North Eastern Province at 23%. Although 94% of respondents who had attended at least some school reported they would accept the vaccine for a child, only 56% of those who had never attended school would do so. The likelihood of accepting one’s own child to be immunized was correlated with province, satisfaction with health care services in the facility attended, age of the caregiver, and level of education. Conclusions Results from this study indicate a need for targeted messages and education on a malaria vaccine, particularly for residents of regions where acceptance is low, older caregivers, and those with low literacy and school-attendance levels. This study provides critical evidence to inform policy for a new malaria vaccine that will support its timely and comprehensive uptake in Kenya. PMID
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Predicting Ebola infection: A malaria-sensitive triage score for Ebola virus disease
Okoni-Williams, Harry Henry; Suma, Mohamed; Mancuso, Brooke; Al-Dikhari, Ahmed; Faouzi, Mohamed
2017-01-01
Background The non-specific symptoms of Ebola Virus Disease (EVD) pose a major problem to triage and isolation efforts at Ebola Treatment Centres (ETCs). Under the current triage protocol, half the patients allocated to high-risk “probable” wards were EVD(-): a misclassification speculated to predispose nosocomial EVD infection. A better understanding of the statistical relevance of individual triage symptoms is essential in resource-poor settings where rapid, laboratory-confirmed diagnostics are often unavailable. Methods/Principal findings This retrospective cohort study analyses the clinical characteristics of 566 patients admitted to the GOAL-Mathaska ETC in Sierra Leone. The diagnostic potential of each characteristic was assessed by multivariate analysis and incorporated into a statistically weighted predictive score, designed to detect EVD as well as discriminate malaria. Of the 566 patients, 28% were EVD(+) and 35% were malaria(+). Malaria was 2-fold more common in EVD(-) patients (p<0.05), and thus an important differential diagnosis. Univariate analyses comparing EVD(+) vs. EVD(-) and EVD(+)/malaria(-) vs. EVD(-)/malaria(+) cohorts revealed 7 characteristics with the highest odds for EVD infection, namely: reported sick-contact, conjunctivitis, diarrhoea, referral-time of 4–9 days, pyrexia, dysphagia and haemorrhage. Oppositely, myalgia was more predictive of EVD(-) or EVD(-)/malaria(+). Including these 8 characteristics in a triage score, we obtained an 89% ability to discriminate EVD(+) from either EVD(-) or EVD(-)/malaria(+). Conclusions/Significance This study proposes a highly predictive and easy-to-use triage tool, which stratifies the risk of EVD infection with 89% discriminative power for both EVD(-) and EVD(-)/malaria(+) differential diagnoses. Improved triage could preserve resources by identifying those in need of more specific differential diagnostics as well as bolster infection prevention/control measures by better compartmentalizing
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Najera, J. A.
1989-01-01
Malaria has been one of the main health problems demanding the attention of WHO from the time the Organization was created. This review of the historical record analyses the different approaches to the malaria problem in the past 40 years and shows how WHO tried to fulfil its constitutional mandate. The article exposes the historical roots of the present situation and helps towards an understanding of current problems and approaches to malaria control. PMID:2670294
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Buffer substitution in malaria rapid diagnostic tests causes false-positive results
2010-01-01
Background Malaria rapid diagnostic tests (RDTs) are kits that generally include 20 to 25 test strips or cassettes, but only a single buffer vial. In field settings, laboratory staff occasionally uses saline, distilled water (liquids for parenteral drugs dilution) or tap water as substitutes for the RDT kit's buffer to compensate for the loss of a diluent bottle. The present study assessed the effect of buffer substitution on the RDT results. Methods Twenty-seven RDT brands were run with EDTA-blood samples of five malaria-free subjects, who were negative for rheumatoid factor and antinuclear antibodies. Saline, distilled water and tap water were used as substitute liquids. RDTs were also run with distilled water, without adding blood. Results were compared to those obtained with the RDT kit's buffer and Plasmodium positive samples. Results Only eight cassettes (in four RDT brands) showed no control line and were considered invalid. Visible test lines occurred for at least one malaria-free sample and one of the substitutes in 20/27 (74%) RDT brands (saline: n = 16; distilled water: n = 17; and tap water: n = 20), and in 15 RDTs which were run with distilled water only. They occurred for all Plasmodium antigens and RDT formats (two-, three- and four-band RDTs). Clearance of the background of the strip was excellent except for saline. The aspects (colour, intensity and crispness) of the control and the false-positive test lines were similar to those obtained with the RDT kits' buffer and Plasmodium positive samples. Conclusion Replacement of the RDT kit's dedicated buffer by saline, distilled water and tap water can cause false-positive test results. PMID:20650003
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Mushi, Adiel K; Schellenberg, Joanna; Mrisho, Mwifadhi; Manzi, Fatuma; Mbuya, Conrad; Mponda, Haji; Mshinda, Hassan; Tanner, Marcel; Alonso, Pedro; Pool, Robert; Schellenberg, David
2008-09-29
Intermittent preventive treatment of malaria in infants (IPTi) using sulphadoxine-pyrimethamine and linked to the expanded programme on immunization (EPI) is a promising strategy for malaria control in young children. As evidence grows on the efficacy of IPTi as public health strategy, information is needed so that this novel control tool can be put into practice promptly, once a policy recommendation is made to implement it. This paper describes the development of a behaviour change communication strategy to support implementation of IPTi by the routine health services in southern Tanzania, in the context of a five-year research programme evaluating the community effectiveness of IPTi. Mixed methods including a rapid qualitative assessment and quantitative health facility survey were used to investigate communities' and providers' knowledge and practices relating to malaria, EPI, sulphadoxine-pyrimethamine and existing health posters. Results were applied to develop an appropriate behaviour change communication strategy for IPTi involving personal communication between mothers and health staff, supported by a brand name and two posters. Malaria in young children was considered to be a nuisance because it causes sleepless nights. Vaccination services were well accepted and their use was considered the mother's responsibility. Babies were generally taken for vaccination despite complaints about fevers and swellings after the injections. Sulphadoxine-pyrimethamine was widely used for malaria treatment and intermittent preventive treatment of malaria in pregnancy, despite widespread rumours of adverse reactions based on hearsay and newspaper reports. Almost all health providers said that they or their spouse were ready to take SP in pregnancy (96%, 223/242). A brand name, key messages and images were developed and pre-tested as behaviour change communication materials. The posters contained public health messages, which explained the intervention itself, how and when
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Comparative benefit of malaria chemoprophylaxis modelled in United Kingdom travellers.
Toovey, Stephen; Nieforth, Keith; Smith, Patrick; Schlagenhauf, Patricia; Adamcova, Miriam; Tatt, Iain; Tomianovic, Danitza; Schnetzler, Gabriel
2014-01-01
Chemoprophylaxis against falciparum malaria is recommended for travellers from non-endemic countries to malarious destinations, but debate continues on benefit, especially with regard to mefloquine. Quantification of benefit for travellers from the United Kingdom (UK) was modelled to assist clinical and public health decision making. The model was constructed utilising: World Tourism Organization data showing total number of arrivals from the UK in countries with moderate or high malaria risk; data from a retrospective UK Clinical Practice Research Datalink (CPRD) drug utilisation study; additional information on chemoprophylaxis, case fatality and tolerability were derived from the travel medicine literature. Chemoprophylaxis with the following agents was considered: atovaquone-proguanil (AP), chloroquine with and without proguanil (C ± P), doxycycline (Dx), mefloquine (Mq). The model was validated for the most recent year with temporally matched datasets for UK travel destinations and imported malaria (2007) against UK Health Protection Agency data on imported malaria. The median (mean) duration of chemoprophylaxis for each agent in weeks (CPRD) was: AP 3.3 (3.5), C ± P 9 (12.1), Dx 8 (10.3), Mq 9 (12.3): the maximum duration of use of all regimens was 52 weeks. The model correctly predicted falciparum malaria deaths and gave a robust estimate of total cases--model: 5 deaths from 1118 cases; UK Health Protection Agency: 5 deaths from 1153 cases. The number needed to take chemoprophylaxis (NNP) to prevent a case of malaria considered against the 'background' reported incidence in non-users of chemoprophylaxis deemed in need of chemoprophylaxis was: C ± P 272, Dx 269, Mq 260, AP 252; the NNP to prevent a UK traveller malaria death was: C ± P 62613, Dx 61923, Mq 59973, AP 58059; increasing the 'background' rate by 50% yielded NNPs of: C ± P 176, Dx 175, Mq 171, AP 168. The impact of substituting atovaquone-proguanil for all mefloquine usage resulted in a 2
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Global malaria connectivity through air travel
2013-01-01
Background Air travel has expanded at an unprecedented rate and continues to do so. Its effects have been seen on malaria in rates of imported cases, local outbreaks in non-endemic areas and the global spread of drug resistance. With elimination and global eradication back on the agenda, changing levels and compositions of imported malaria in malaria-free countries, and the threat of artemisinin resistance spreading from Southeast Asia, there is a need to better understand how the modern flow of air passengers connects each Plasmodium falciparum- and Plasmodium vivax-endemic region to the rest of the world. Methods Recently constructed global P. falciparum and P.vivax malaria risk maps, along with data on flight schedules and modelled passenger flows across the air network, were combined to describe and quantify global malaria connectivity through air travel. Network analysis approaches were then utilized to describe and quantify the patterns that exist in passenger flows weighted by malaria prevalence. Finally, the connectivity within and to the Southeast Asia region where the threat of imported artemisinin resistance arising is highest, was examined to highlight risk routes for its spread. Results The analyses demonstrate the substantial connectivity that now exists between and from malaria-endemic regions through air travel. While the air network provides connections to previously isolated malarious regions, it is clear that great variations exist, with significant regional communities of airports connected by higher rates of flow standing out. The structures of these communities are often not geographically coherent, with historical, economic and cultural ties evident, and variations between P. falciparum and P. vivax clear. Moreover, results highlight how well connected the malaria-endemic areas of Africa are now to Southeast Asia, illustrating the many possible routes that artemisinin-resistant strains could take. Discussion The continuing growth in air
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The influence of mosquito resting behaviour and associated microclimate for malaria risk
2011-01-01
Background The majority of the mosquito and parasite life-history traits that combine to determine malaria transmission intensity are temperature sensitive. In most cases, the process-based models used to estimate malaria risk and inform control and prevention strategies utilize measures of mean outdoor temperature. Evidence suggests, however, that certain malaria vectors can spend large parts of their adult life resting indoors. Presentation of hypothesis If significant proportions of mosquitoes are resting indoors and indoor conditions differ markedly from ambient conditions, simple use of outdoor temperatures will not provide reliable estimates of malaria transmission intensity. To date, few studies have quantified the differential effects of indoor vs outdoor temperatures explicitly, reflecting a lack of proper understanding of mosquito resting behaviour and associated microclimate. Testing the hypothesis Published records from 8 village sites in East Africa revealed temperatures to be warmer indoors than outdoors and to generally show less daily variation. Exploring the effects of these temperatures on malaria parasite development rate suggested indoor-resting mosquitoes could transmit malaria between 0.3 and 22.5 days earlier than outdoor-resting mosquitoes. These differences translate to increases in transmission risk ranging from 5 to approaching 3,000%, relative to predictions based on outdoor temperatures. The pattern appears robust for low- and highland areas, with differences increasing with altitude. Implications of the hypothesis Differences in indoor vs outdoor environments lead to large differences in the limits and the intensity of malaria transmission. This finding highlights a need to better understand mosquito resting behaviour and the associated microclimate, and to broaden assessments of transmission ecology and risk to consider the potentially important role of endophily. PMID:21736735
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Timing of malaria messages for target audience on radio airwaves
2012-01-01
Background Due to the limitations of face-to-face communication to teach families how to manage, control and prevent malaria, national and local malaria programmes try to reach people through the radio. However, information regarding the timing of radio messages for the target audiences is lacking. Methods Within a large-scale trial (Clinicaltrials.gov: NCT00565071), data regarding the time at which people listen to the radio was collected from 1,628 consenting outpatients (and caregivers for minors) attending six rural government primary level health care centres in Bushenyi and Iganga districts of Uganda from February to July 2011. Results The majority of households, 1,099 (67.5%) owned a radio. The majority, 1,221 (86.3%), participants had heard about malaria from the radio. Some participants started listening to the radio at about 06.00 East African local time (EAT). The peak hours at which people listen to the radio are 12.00-14.00 and 18.00-23.00 local time. The median time of listening to the radio by men is 20.00 (inter-quartile range (IQR): 18.30-21.00) and women 19.30 (IQR: 13.00-20.30). Conclusion Planners of malaria radio interventions need to broadcast their messages within the two peak EAT of 12.00-14.00 and 18.00-23.00. PMID:22905781
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Kobayashi, Tamaki; Gamboa, Dionicia; Ndiaye, Daouda; Cui, Liwang; Sutton, Patrick L.; Vinetz, Joseph M.
2015-01-01
Diagnosis is “the act of identifying a disease, illness, or problem by examining someone or something.” When an individual with acute fever presents for clinical attention, accurate diagnosis leading to specific, prompt treatment often saves lives. As applied to malaria, not only individual patient diagnosis is important but also assessing population-level malaria prevalence using appropriate diagnostic methods is essential for public health purposes. Similarly, identifying (diagnosing) fake antimalarial medications prevents the use of counterfeit drugs that can have disastrous effects. Therefore, accurate diagnosis in broad areas related to malaria is fundamental to improving health-care delivery, informing funding agencies of current malaria situations, and aiding in the prioritization of regional and national control efforts. The International Centers of Excellence for Malaria Research (ICEMR), supported by the U.S. National Institute of Allergy and Infectious Diseases, has collaborated on global efforts to improve malaria diagnostics by working to harmonize and systematize procedures across different regions where endemicity and financial resources vary. In this article, the different diagnostic methods used across each ICEMR are reviewed and challenges are discussed. PMID:26259937
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Suswardany, Dwi Linna; Sibbritt, David W.; Supardi, Sudibyo; Pardosi, Jerico F.; Chang, Sungwon; Adams, Jon
2017-01-01
Background The level of traditional medicine use, particularly Jamu use, in Indonesia is substantial. Indonesians do not always seek timely treatment for malaria and may seek self-medication via traditional medicine. This paper reports findings from the first focused analyses of traditional medicine use for malaria in Indonesia and the first such analyses worldwide to draw upon a large sample of respondents across high-risk malaria endemic areas. Methods A sub-study of the Indonesia Basic Health Research/Riskesdas Study 2010 focused on 12,226 adults aged 15 years and above residing in high-risk malaria-endemic provinces. Logistic regression was undertaken to determine the significant associations for traditional medicine use for malaria symptoms. Findings Approximately one in five respondents use traditional medicine for malaria symptoms and the vast majority experiencing multiple episodes of malaria use traditional medicine alongside free antimalarial drug treatments. Respondents consuming traditional medicine for general health/common illness purposes every day (odds ratio: 3.75, 95% Confidence Interval: 2.93 4.79), those without a hospital in local vicinity (odds ratio: 1.31, 95% Confidence Interval: 1.10 1.57), and those living in poorer quality housing, were more likely to use traditional medicine for malaria symptoms. Conclusion A substantial percentage of those with malaria symptoms utilize traditional medicine for treating their malaria symptoms. In order to promote safe and effective malaria treatment, all providing malaria care in Indonesia need to enquire with their patients about possible traditional medicine use. PMID:28329019
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Malaria Evolution in South Asia: Knowledge for Control and Elimination
Narayanasamy, Krishnamoorthy; Chery, Laura; Basu, Analabha; Duraisingh, Manoj T.; Escalante, Ananias; Fowble, Joseph; Guler, Jennifer L.; Herricks, Thurston; Kumar, Ashwani; Majumder, Partha; Maki, Jennifer; Mascarenhas, Anjali; Rodrigues, Janneth; Roy, Bikram; Sen, Somdutta; Shastri, Jayanthi; Smith, Joseph; Valecha, Neena; White, John; Rathod, Pradipsinh K.
2013-01-01
The study of malaria parasites on the Indian subcontinent should help us understand unexpected disease outbreaks and unpredictable disease presentations from Plasmodium falciparum and from Plasmodium vivax infections. The Malaria Evolution in South Asia (MESA) research program is one of ten International Centers of Excellence for Malaria Research (ICEMR) sponsored by the US National Institute of Health. In this second of two reviews, we describe why population structures of Plasmodia in India will be characterized and how we will determine their consequences on disease presentation, outcome and patterns. Specific projects will determine if genetic diversity, possibly driven by parasites with higher genetic plasticity, plays a role in changing epidemiology, pathogenesis, vector competence of parasite populations, and whether innate human genetic traits protect Indians from malaria today. Deep local clinical knowledge of malaria in India will be supplemented by basic scientists who bring new research tools. Such tools will include whole genome sequencing and analysis methods; in vitro assays to measure genome plasticity, RBC cytoadhesion, invasion, and deformability; mosquito infectivity assays to evaluate changing parasite-vector compatibilities; and host genetics to understand protective traits in Indian populations. The MESA-ICEMR study sites span diagonally across India, including a mixture of very urban and rural hospitals, each with very different disease patterns and patient populations. Research partnerships include government-associated research institutes, private medical schools, city and state government hospitals, and hospitals with industry ties. Between 2012-2017, in addition to developing clinical research and basic science infrastructure at new clinical sites, our training workshops will engage new scientists and clinicians throughout South Asia in the malaria research field. PMID:22266213
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2013-01-01
Background The RTS,S/AS malaria candidate vaccine is being developed with the intent to be delivered, if approved, through the Expanded Programme on Immunization (EPI) of the World Health Organization. Safety, immunogenicity and efficacy of the RTS,S/AS02D vaccine candidate when integrated into a standard EPI schedule for infants have been reported over a nine-month surveillance period. This paper describes results following 20 months of follow up. Methods This Phase IIb, single-centre, randomized controlled trial enrolled 340 infants in Tanzania to receive three doses of RTS,S/AS02D or hepatitis B vaccine at 8, 12, and 16 weeks of age. All infants also received DTPw/Hib (diphtheria and tetanus toxoids, whole-cell pertussis vaccine, conjugated Haemophilus influenzae type b vaccine) at the same timepoints. The study was double-blinded to month 9 and single-blinded from months 9 to 20. Results From month 0 to 20, at least one SAE was reported in 57/170 infants who received RTS,S/AS02D (33.5%; 95% confidence interval [CI]: 26.5, 41.2) and 62/170 infants who received hepatitis B vaccine (36.5%; 95% CI: 29.2, 44.2). The SAE profile was similar in both vaccine groups; none were considered to be related to vaccination. At month 20, 18 months after completion of vaccination, 71.8% of recipients of RTS,S/AS02D and 3.8% of recipients of hepatitis B vaccine had seropositive titres for anti-CS antibodies; seroprotective levels of anti-HBs antibodies remained in 100% of recipients of RTS,S/AS02D and 97.7% recipients of hepatitis B vaccine. Anti-HBs antibody GMTs were higher in the RTS,S/AS02D group at all post-vaccination time points compared to control. According to protocol population, vaccine efficacy against multiple episodes of malaria disease was 50.7% (95% CI: -6.5 to 77.1, p = 0.072) and 26.7% (95% CI: -33.1 to 59.6, p = 0.307) over 12 and 18 months post vaccination, respectively. In the Intention to Treat population, over the 20-month follow up, vaccine
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Ferrao, Joao L; Niquisse, Sergio; Mendes, Jorge M; Painho, Marco
2018-04-19
Background : Malaria continues to be a major public health concern in Africa. Approximately 3.2 billion people worldwide are still at risk of contracting malaria, and 80% of deaths caused by malaria are concentrated in only 15 countries, most of which are in Africa. These high-burden countries have achieved a lower than average reduction of malaria incidence and mortality, and Mozambique is among these countries. Malaria eradication is therefore one of Mozambique’s main priorities. Few studies on malaria have been carried out in Chimoio, and there is no malaria map risk of the area. This map is important to identify areas at risk for application of Public Precision Health approaches. By using GIS-based spatial modelling techniques, the research goal of this article was to map and model malaria risk areas using climate, socio-demographic and clinical variables in Chimoio, Mozambique. Methods : A 30 m × 30 m Landsat image, ArcGIS 10.2 and BioclimData were used. A conceptual model for spatial problems was used to create the final risk map. The risks factors used were: the mean temperature, precipitation, altitude, slope, distance to water bodies, distance to roads, NDVI, land use and land cover, malaria prevalence and population density. Layers were created in a raster dataset. For class value comparisons between layers, numeric values were assigned to classes within each map layer, giving them the same importance. The input dataset were ranked, with different weights according to their suitability. The reclassified outputs of the data were combined. Results : Chimoio presented 96% moderate risk and 4% high-risk areas. The map showed that the central and south-west “Residential areas”, namely, Centro Hipico, Trangapsso, Bairro 5 and 1° de Maio, had a high risk of malaria, while the rest of the residential areas had a moderate risk. Conclusions : The entire Chimoio population is at risk of contracting malaria, and the precise estimation of
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Pribluda, Victor S; Barojas, Adrian; Añez, Arletta; López, Cecilia G; Figueroa, Ruth; Herrera, Roxana; Nakao, Gladys; Nogueira, Fernando Ha; Pianetti, Gerson A; Povoa, Marinete M; Viana, Giselle Mr; Gomes, Margarete S Mendonça; Escobar, Jose P; Sierra, Olga L Muñoz; Norena, Susana P Rendon; Veloz, Raúl; Bravo, Marcy Silva; Aldás, Martha R; Hindssemple, Alison; Collins, Marilyn; Ceron, Nicolas; Krishnalall, Karanchand; Adhin, Malti; Bretas, Gustavo; Hernandez, Nelly; Mendoza, Marjorie; Smine, Abdelkrim; Chibwe, Kennedy; Lukulay, Patrick; Evans, Lawrence
2012-06-15
Ensuring the quality of malaria medicines is crucial in working toward malaria control and eventual elimination. Unlike other validated tests that can assess all critical quality attributes, which is the standard for determining the quality of medicines, basic tests are significantly less expensive, faster, and require less skilled labour; yet, these tests provide reproducible data and information on several critical quality attributes, such as identity, purity, content, and disintegration. Visual and physical inspection also provides valuable information about the manufacturing and the labelling of medicines, and in many cases this inspection is sufficient to detect counterfeit medicines. The Promoting the Quality of Medicines (PQM) programme has provided technical assistance to Amazon Malaria Initiative (AMI) countries to implement the use of basic tests as a key screening mechanism to assess the quality of malaria medicines available to patients in decentralized regions. Trained personnel from the National Malaria Control Programmes (NMCPs), often in collaboration with country's Official Medicine Control Laboratory (OMCL), developed country- specific protocols that encompassed sampling methods, sample analysis, and data reporting. Sampling sites were selected based on malaria burden, accessibility, and geographical location. Convenience sampling was performed and countries were recommended to store the sampled medicines under conditions that did not compromise their quality. Basic analytical tests, such as disintegration and thin layer chromatography (TLC), were performed utilizing a portable mini-laboratory. Results were originally presented at regional meetings in a non-standardized format that lacked relevant medicines information. However, since 2008 information has been submitted utilizing a template specifically developed by PQM for that purpose. From 2005 to 2010, the quality of 1,663 malaria medicines from seven AMI countries was evaluated, mostly
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Liverani, Marco; Charlwood, Jacques Derek; Lawford, Harriet; Yeung, Shunmay
2017-10-13
Large-scale use of insecticide-treated nets and indoor residual spraying have contributed to a significant decrease in malaria transmission worldwide. Further reduction and progress towards elimination, however, require complementary control measures which can address the remaining gaps in protection from mosquito bites. Following the development of novel pyrethroids with high knockdown effects on malaria vectors, programmatic use of spatial repellents has been suggested as one potential strategy to fill the gaps. This report explores social and contextual factors that may influence the relevance, uptake and sustainable use of a spatial repellent in two remote villages in Mondulkiri province, Cambodia, with endemic malaria transmission. The repellent consisted of polyethylene emanators, held in an open plastic frame and impregnated with 10% metofluthrin. In a baseline survey, 90.9% of households in Ou Chra (n = 30/33) and 96.6% in Pu Cha (n = 57/59) were interviewed. Behavioural data were collected for all household occupants (n = 448). In both villages, there were times and places in which people remained exposed to mosquito bites. Prior to the installation of the repellent, 50.6 and 59.5% of respondents noted that bites occurred "very often" inside the house and in the outdoor area surrounding the house, respectively. Indoor biting was reported to occur more frequently in the evening, followed by at night, while outdoor biting occurred more frequently in the early morning. In a follow-up survey, spatial repellents were well received in both villages, although 63.2% of respondents would not replace bed nets with repellents. Most participants (96.6%) were willing to use the product again; the mean willingness to pay was US$ 0.3 per unit. A preference for local procurement methods emerged. Widespread use of spatial repellents would not fill all protective gaps, but, if their entomological efficacy can be ascertained, outdoor application has the potential to