[Aspects of the social realities of children and adolescents seen at a reference service for bancroftian filariasis in Recife, state of Pernambuco].

PubMed

Mattos, Denise; Mota, Solange; Dreyer, Gerusa

2008-01-01

The authors report on aspects of the social realities of children and adolescents living in Jaboatão dos Guararapes, State of Pernambuco, who were diagnosed with Bancroftian filariasis infection and were treated at the Filariasis Teaching, Research and Care Center of the Federal University of Pernambuco (Health Sciences Center), which is a tertiary-level reference service for filariasis. The patients' housing conditions were quantified and classified as subhuman, with a direct relationship with the maintenance of Bancroftian filariasis transmission, and the authors highlight the need for political decisions regarding the implementation of basic sanitation projects.

A pilot study on the status of lymphatic filariasis in a rural community of Bihar.

PubMed

Das, V N R; Siddiqui, N A; Kumar, N; Verma, N; Verma, R B; Dinesh, D S; Kar, S K; Das, P

2006-03-01

A pilot study of lymphatic filariasis was conducted in two contiguous villages of Patna district in Bihar situated at the side of the river Ganges, known to be endemic for lymphatic filariasis, to study present status of transmission parameters of filariasis. Of the 1872 persons examined, 8.4% were found asymptomatic but microfilaraemic. Morbidity pattern due to filarial infection showed an increase with advancement of age and significantly high in males as compared to female (p < 0.001). Acute and chronic filarial disease was observed as 0.5% and 9% respectively. Microfilaria was found in 10% of acute and 11.2% of chronic filarial cases. The Mf rate was found to be 9.9% in males and 9.0% in females respectively. The parasite species was identified as W. bancrofti. The vector fauna surveyed show highest prevalence of vector species of Cx. quinquefasciatus (43%) in both domestic as well as predomestic area in the community. Other species like Cx. vishnui and Ma. uniformis were also seen. Each household and predomestic area was searched for mosquito fauna at night. The infection rate in vectors was found to be 14% and infectivity rate (L3) was 8%. The filariasis cases detected in the study were treated with 12 days course of DEC 6 mg/kg body weight.

[Serpiginous calcifications in breast filariasis: A descriptor not included in the BI-RADS classification system].

PubMed

Mora-Encinas, J P; Martín-Martín, B; Martín-Martín, L; Mora-Monago, R

2015-01-01

Filariasis is a parasitic disease with a benign course caused by nematodes. Filariasis is endemic in some tropical regions, and immigration has made it increasingly common in some centers in Spain. The death of the parasites can lead to calcifications that are visible in mammograms; these calcifications have specific characteristics and should not be confused with those arising in other diseases. However, the appearance of calcifications due to filariasis is not included in the most common systems used for the classification of calcifications on mammograms (BI-RADS), and this can lead to confusion. In this article, we discuss the need to update classification systems and warn radiologists about the appearance of these calcifications to ensure their correct diagnosis and avoid confusion with other diseases. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

The Socioeconomic Impact of Lymphatic Filariasis in Tropical Countries

ERIC Educational Resources Information Center

Nwoke, Bertram Ekejiuba Bright; Nwoke, Eunice Anyalewechi; Dozie, Ikechukwu Nosike Simplicius

2007-01-01

Lymphatic filariasis (LF) is an endemic parasitic disease and a major cause of acute and chronic morbidity and incapacitation with devastating public health and socio-economic consequences. It exacerbates poor conditions of afflicted persons and endemic communities through reduced or lost labour supply and productivity. Stigmatisation and…

[Present status of bancroftian filariasis in Maceió, State of Alagoas, Brazil].

PubMed

Fontes, G; Brito, A C; Calheiros, C M; Antunes, C M; da Rocha, E M

1994-01-01

Epidemiological and entomological surveys were carried out in the human and mosquito populations in Maceió, Alagoas, in order to assess the present status of bancroftian lymphatic filariasis. Examination of thick blood smears of 10,450 students from different areas of the city revealed 0.66% Wuchereria bancrofti microfilaria carriers. The distribution of filariasis is focal in the city, 80% of the individuals with patent infection living in two neighboring areas with 1.24% and 5.25% prevalence. Parallel studies performed with samples of all age groups in the human population showed similar microfilaria prevalence rates observed previously in the student survey. However, thick blood smears taken from members of families with at least one subject with patent infection gave a prevalence six times greater suggesting, increased transmission in households. The percentage of carriers was higher in the youngest age group (< 20 years). Culex quinquefasciatus mosquitos caught at the locations where the autochthonous cases were found presented natural infection rates ranging from 0.28% to 4.62%. The combination of all these findings indicates occurrence of active transmission of W. bancrofti in the urban area of Maceió, Alagoas State. Based on these data, measures for the potential control of filariasis were planned.

A Comprehensive, Model-Based Review of Vaccine and Repeat Infection Trials for Filariasis

PubMed Central

Morris, C. Paul; Evans, Holly; Larsen, Sasha E.

2013-01-01

SUMMARY Filarial worms cause highly morbid diseases such as elephantiasis and river blindness. Since the 1940s, researchers have conducted vaccine trials in 27 different animal models of filariasis. Although no vaccine trial in a permissive model of filariasis has provided sterilizing immunity, great strides have been made toward developing vaccines that could block transmission, decrease pathological sequelae, or decrease susceptibility to infection. In this review, we have organized, to the best of our ability, all published filaria vaccine trials and reviewed them in the context of the animal models used. Additionally, we provide information on the life cycle, disease phenotype, concomitant immunity, and natural immunity during primary and secondary infections for 24 different filaria models. PMID:23824365

Identification and characterization of nematode specific protective epitopes of Brugia malayi TRX towards development of synthetic vaccine construct for lymphatic filariasis.

PubMed

Madhumathi, Jayaprakasam; Prince, Prabhu Rajaiah; Anugraha, Gandhirajan; Kiran, Pote; Rao, Donthamsetty Nageswara; Reddy, Maryada Venkata Rami; Kaliraj, Perumal

2010-07-12

Although multi-epitope vaccines have been evaluated for various diseases, they have not yet been investigated for lymphatic filariasis. Here, we report for the first time identification of two immunodominant B epitopes (TRXP1 and TRXP2) from the antioxidant Brugia malayi thioredoxin by studying their immune responses in mice model and human subjects. TRXP1 was also found to harbor a T epitope recognized by human PBMCs and mice splenocytes. Further, the epitopic peptides were synthesized as a single peptide conjugate (PC1) and their prophylactic efficacy was tested in a murine model of filariasis with L3 larvae. PC1 conferred a significantly high protection (75.14%) (P < 0.0001) compared to control (3.7%) and recombinant TRX (63.03%) (P < 0.018) in experimental filariasis. Our results suggest that multi-epitope vaccines could be a promising strategy in the control of lymphatic filariasis.

Travel-related schistosomiasis, strongyloidiasis, filariasis, and toxocariasis: the risk of infection and the diagnostic relevance of blood eosinophilia.

PubMed

Baaten, Gijs G; Sonder, Gerard J; van Gool, Tom; Kint, Joan A; van den Hoek, Anneke

2011-04-05

This study prospectively assessed the occurrence of clinical and subclinical schistosomiasis, strongyloidiasis, filariasis, and toxocariasis, and the screening value of eosinophilia in adult short-term travelers to helminth-endemic countries. Visitors of a pre-travel health advice centre donated blood samples for serology and blood cell count before and after travel. Samples were tested for eosinophilia, and for antibodies against schistosomiasis, strongyloidiasis, filariasis, and toxocariasis. Previous infection was defined as seropositivity in pre- and post-travel samples. Recent infection was defined as a seroconversion. Symptoms of parasitic disease were recorded in a structured diary. Previous infection was found in 112 of 1207 subjects: schistosomiasis in 2.7%, strongyloidiasis in 2.4%, filariasis in 3.4%, and toxocariasis in 1.8%. Recent schistosomiasis was found in 0.51% of susceptible subjects at risk, strongyloidiasis in 0.25%, filariasis in 0.09%, and toxocariasis in 0.08%. The incidence rate per 1000 person-months was 6.4, 3.2, 1.1, and 1.1, respectively. Recent infections were largely contracted in Asia. The positive predictive value of eosinophilia for diagnosis was 15% for previous infection and 0% for recent infection. None of the symptoms studied had any positive predictive value. The chance of infection with schistosomiasis, strongyloidiasis, filariasis, and toxocariasis during one short-term journey to an endemic area is low. However, previous stay leads to a cumulative risk of infection. Testing for eosinophilia appeared to be of no value in routine screening of asymptomatic travelers for the four helminthic infections. Findings need to be replicated in larger prospective studies.

Cystic lymph node enlargement of the neck: filariasis as a rare differential diagnosis in MRI.

PubMed

Schick, Christoph; Thalhammer, Axel; Balzer, Jörn O; Abolmaali, Nasreddin; Vogl, Thomas J

2002-09-01

Cervical lymph node enlargement is a common feature of most inflammatory and neoplastic entities of the head and neck. Filariasis can lead to lymphangiectasis resembling lymph node enlargement; however, this is a rare differential diagnosis in European patients. As ethnic minorities are increasing throughout Europe and personal mobility, e.g. during holidays, is increasing, such rare differential diagnoses have to be taken into consideration. We present the case of an Iraqi patient referred to as for a suspected cystic lymph node mass that was verified histologically by open MRI biopsy and proved to be a cystic manifestation of filariasis.

Data base management system for lymphatic filariasis--a neglected tropical disease.

PubMed

Upadhyayula, Suryanaryana Murty; Mutheneni, Srinivasa Rao; Kadiri, Madhusudhan Rao; Kumaraswamy, Sriram; Nelaturu, Sarat Chandra Babu

2012-01-01

Researchers working in the area of Public Health are being confronted with large volumes of data on various aspects of entomology and epidemiology. To obtain the relevant information out of these data requires particular database management system. In this paper, we have described about the usages of our developed database on lymphatic filariasis. This database application is developed using Model View Controller (MVC) architecture, with MySQL as database and a web based interface. We have collected and incorporated the data on filariasis in the database from Karimnagar, Chittoor, East and West Godavari districts of Andhra Pradesh, India. The importance of this database is to store the collected data, retrieve the information and produce various combinational reports on filarial aspects which in turn will help the public health officials to understand the burden of disease in a particular locality. This information is likely to have an imperative role on decision making for effective control of filarial disease and integrated vector management operations.

The impact of lymphatic filariasis on labour inputs in southern India: results of a multi-site study.

PubMed

Ramaiah, K D; Radhamani, M P; John, K R; Evans, D B; Guyatt, H; Joseph, A; Datta, M; Vanamail, P

2000-06-01

A multi-site study was undertaken, in the rural areas of three districts in Tamil Nadu state, in southern India, to examine the impact of acute and chronic forms of lymphatic filariasis, caused by infection with Wuchereria bancrofti, on labour inputs. More than half of the acute episodes of adenolymphangitis (ADL) observed in the study communities caused total disability. The mean (S.D.) time that each ADL case was able to allocate to economic activity each day during these acute episodes was much less than seen in the controls matched for sex, age and occupation [0.97 (2.36) v. 4.48 (3.82) h; P < 0.01]. The acute disease also severely affected domestic activities, with female ADL cases spending only 1.54 (2.12) h/day on domestic activity, compared with 4.18 (2.61) h by controls. The subjects with chronic filariasis also spent significantly less time in economic activity than their matched controls [4.40 (3.79) v. 5.13 (3.83) h/day; P < 0.01). Although the acute episodes have a dramatic effect on the productivity of the affected individual, the labour loss caused by chronic disease is more serious, as the manifestations of chronic disease mostly affect the most productive age-groups, persist for life and are mostly irreversible. The adverse impact of acute and chronic filariasis was observed in males and females, farmers and non-farmers and during the rainy, winter and summer seasons. It is estimated that about 3.8% of the potential labour inputs of the men and 0.77% of those of the women were lost because of lymphatic filariasis. In addition to this loss, the total economic burden of the disease must include the costs of treatment and other health care and of the resources spent on control programmes. Estimates of the disease burden are likely to be useful in determining the costs and benefits of the recently launched campaign to eliminate lymphatic filariasis.

Salt fortified with diethylcarbamazine (DEC) as an effective intervention for lymphatic filariasis, with lessons learned from salt iodization programmes.

PubMed

Houston, R

2000-01-01

DEC-fortified salt has been used successfully as a principal public health tool to eliminate lymphatic filariasis (LF) in China and, less extensively, in several other countries. Studies from 1967 to the present conducted in Brazil, Japan, Tanzania, India, China, and Taiwan involving administration of DEC salt for 18 days to 1 year, have shown this intervention to be effective for both bancroftian and brugian filariasis, as measured by reductions in both microfilarial density and positivity, and in some studies through reduction in mosquito positivity rates as well. Furthermore, studies suggest specific advantages from using DEC salt, including lack of side effects, particularly for bancroftian filariasis, and ability to reduce prevalence below 1% when used in conjunction with standard regimens of DEC tablets. However, use of DEC salt as a control tool suffers from a concern that health authorities might find it difficult to manage a programme involving a commodity such as salt. In the past decade, the very successful global efforts to eliminate iodine deficiency through universal salt iodization have demonstrated that partnership with the salt industry can be both successful and effective as a public health tool. Use of DEC salt can be most successfully implemented in areas in which (a) there is adequate governmental support for its use and for elimination of filariasis, (b) filariasis-endemic areas are clearly defined, (c) political leaders, health officials and the salt industry agree that DEC salt is an appropriate intervention, (d) the salt industry is well-organized and has known distribution patterns, (e) a successful national salt iodization effort exists, (f) a monitoring system exists that ensures adequacy of salt iodine content during production and that can also measure household coverage, and (g) measurement of impact on transmission of LF with the new antigen or filarial DNA detection methods can be established. There are advantages and disadvantages

Lymphatic filariasis in Uganda: baseline investigations in Lira, Soroti and Katakwi districts.

PubMed

Onapa, A W; Simonsen, P E; Pedersen, E M; Okello, D O

2001-01-01

Baseline epidemiological investigations on lymphatic filariasis were conducted for the first time in Uganda in 3 communities in the districts of Lira (Alebtong area), Soroti (Lwala area) and Katakwi (Obalanga area), located to the north of Lake Kyoga at an altitude of 1000-1100 m above sea level. Individuals from the communities were examined, in April-August 1998, for Wuchereria bancrofti specific circulating antigen (by ICT card test), microfilaraemia (by counting chamber and stained blood-smear techniques) and chronic clinical manifestations of lymphatic filariasis. Endophilic mosquitoes were sampled and dissected for filarial larvae. Prevalences of circulating filarial antigen positivity were 29%, 18% and 30% in the Alebtong, Lwala and Obalanga communities, respectively. Microfilaria (mf) prevalences were 18%, 9% and 21%, and geometric mean mf intensities among mf-positive individuals were 306, 171 and 402 mf/mL blood, in the same communities. Examination of stained blood smears revealed mf of both W. bancrofti and Mansonella perstans, but more than 80% of mf-positive individuals harboured the first of these parasites. Prevalences of hydrocoele in adult (> or = 20 years) males were 28%, 7% and 17%, and prevalences of limb elephantiasis in adults were 9%, 4% and 4%, in the Alebtong, Lwala and Obalanga communities, respectively. Anopheles gambiae s.l. (mainly An. gambiae s.s.) and An. funestus were common in all 3 communities, and showed W. bancrofti infectivity rates of 1.1-1.7% and 1.3-2.9%, respectively. It is concluded that lymphatic filariasis is highly endemic in these high-altitude areas of Uganda, with An. gambiae s.l. and An. funestus being the main vectors.

Morbidity management and disability prevention for lymphatic filariasis in Sri Lanka: Current status and future prospects.

PubMed

Chandrasena, Nilmini; Premaratna, Ranjan; Gunaratna, Indeewarie E; de Silva, Nilanthi R

2018-05-01

Sri Lanka was acknowledged to have eliminated lymphatic filariasis (LF) as a public health problem in 2016, largely due to its success in Mass Drug Administration (MDA) to interrupt disease transmission. Analysis of the Strengths, Weaknesses, Opportunities and Threats (SWOT) of the national Morbidity Management and Disability Prevention (MMDP) program, the other pillar of the LF control program, was carried out with the objective of evaluating it and providing recommendations to optimize the use of available resources. A situation analysis of the MMDP activities provided by the state health sector was carried out using published records, in-depth interviews with key informants of the Anti Filariasis Campaign, site-visits to filariasis clinics with informal discussions with clinic workforce and personal communications to identify strengths and weaknesses; and opportunities to overcome weaknesses and perceived threats to the program were explored. The principal strength of the MMDP program was the filariasis clinics operational in most endemic districts of Sri Lanka, providing free health care and health education to clinic attendees. The weaknesses identified were the low accessibility of clinics, incomplete coverage of the endemic region and lack of facilities for rehabilitation. The perceived threats were diversion of staff and resources for control of other vector-borne infections, under-utilization of clinics and non-compliance with recommended treatment. Enhanced high level commitment for MMDP, wider publicity and referral systems, integration of MMDP with other disease management services and collaboration with welfare organizations and research groups were identified as opportunities to overcome weaknesses and challenges. The recommended basic package of MMDP was functional in most of the LF-endemic region. The highlighted weaknesses and challenges, unless addressed, may threaten program sustainability. The identified opportunities for improvement of the

Will mass drug administration eliminate lymphatic filariasis? Evidence from northern coastal Tanzania.

PubMed

Parker, Melissa; Allen, Tim

2013-07-01

This article documents understandings and responses to mass drug administration (MDA) for the treatment and prevention of lymphatic filariasis among adults and children in northern coastal Tanzania from 2004 to 2011. Assessment of village-level distribution registers, combined with self-reported drug uptake surveys of adults, participant observation and interviews, revealed that at study sites in Pangani and Muheza districts the uptake of drugs was persistently low. The majority of people living at these highly endemic locations either did not receive or actively rejected free treatment. A combination of social, economic and political reasons explain the low uptake of drugs. These include a fear of treatment (attributable, in part, to a lack of trust in international aid and a questioning of the motives behind the distribution); divergence between biomedical and local understandings of lymphatic filariasis; and limited and ineffective communication about the rationale for mass treatment. Other contributory factors are the reliance upon volunteers for distribution within villages and, in some locations, strained relationships between different groups of people within villages as well as between local leaders and government officials. The article also highlights a disjuncture between self-reported uptake of drugs by adults at a village level and the higher uptake of drugs recorded in official reports. The latter informs claims that elimination will be a possibility by 2020. This gives voice to a broader problem: there is considerable pressure for those implementing MDA to report positive results. The very real challenges of making MDA work are pushed to one side - adding to a rhetoric of success at the expense of engaging with local realities. It is vital to address the kind of issues raised in this article if current attempts to eliminate lymphatic filariasis in mainland coastal Tanzania are to achieve their goal.

Can vector control play a useful supplementary role against bancroftian filariasis?

PubMed Central

Maxwell, C. A.; Mohammed, K.; Kisumku, U.; Curtis, C. F.

1999-01-01

A single campaign of mass treatment for bancroftian filariasis with diethylcarbamazine (DEC) in Makunduchi, a town in Zanzibar, United Republic of Tanzania, combined with elimination of mosquito breeding in pit latrines with polystyrene beads was followed by a progressive decline over a 5-year period in the microfilarial rate from 49% to 3%. Evidence that vector control had contributed to this long-term decline was obtained by comparison with another town, Moga, where a DEC campaign was used without vector control and where resurgence of microfilariae could be observed 3-6 years after the campaign. In Zanzibar town, treatment of 3844 wet pit latrines and cesspits with polystyrene beads reduced the adult mosquito population in houses by about 65%. Supplementary treatment of open drains and marshes with Bacillus sphaericus produced little or no additional reduction compared to a sector of the town where only pit treatment with polystyrene was carried out. The cost and effort of achieving the 65% reduction in mosquito population could hardly be justified for its impact on filariasis alone, but its noticeable impact on biting nuisance might help to gain community support for an integrated programme. PMID:10083712

Issues in Delivering Morbidity Management for Lymphatic Filariasis Elimination: A Study in Pondicherry, South India

PubMed Central

Kumari, A. Krishna; J, Yuvaraj; Das, L. K

2012-01-01

Lymphatic filariasis is a vector borne parasitic disease causing long term disability. The Global Programme to Eliminate Lymphatic Filariasis aims to achieve its objective through two strategies; Mass Drug Administration (MDA) to interrupt transmission and Morbidity Management (MM) to manage disability for those already affected. MDA is going on in full swing in endemic areas; but MM is lagging behind. An exploratory study was conducted in Pondicherry through focus group discussions to find out whether there are delivery issues if any, in the MM programme and get suggestions from end users. The study results show that MM has not received the same attention as MDA and there are shortcomings in the delivery mechanism of the programme. The importance of these findings are discussed and suggestions given for improving the programme. PMID:22654597

A comprehensive assessment of lymphatic filariasis in Sri Lanka six years after cessation of mass drug administration.

PubMed

Rao, Ramakrishna U; Nagodavithana, Kumara C; Samarasekera, Sandhya D; Wijegunawardana, Asha D; Premakumara, Welmillage D Y; Perera, Samudrika N; Settinayake, Sunil; Miller, J Phillip; Weil, Gary J

2014-01-01

The Sri Lankan Anti-Filariasis Campaign conducted 5 rounds of mass drug administration (MDA) with diethycarbamazine plus albendazole between 2002 and 2006. We now report results of a comprehensive surveillance program that assessed the lymphatic filariasis (LF) situation in Sri Lanka 6 years after cessation of MDA. Transmission assessment surveys (TAS) were performed per WHO guidelines in primary school children in 11 evaluation units (EUs) in all 8 formerly endemic districts. All EUs easily satisfied WHO criteria for stopping MDA. Comprehensive surveillance was performed in 19 Public Health Inspector (PHI) areas (subdistrict health administrative units). The surveillance package included cross-sectional community surveys for microfilaremia (Mf) and circulating filarial antigenemia (CFA), school surveys for CFA and anti-filarial antibodies, and collection of Culex mosquitoes with gravid traps for detection of filarial DNA (molecular xenomonitoring, MX). Provisional target rates for interruption of LF transmission were community CFA <2%, antibody in school children <2%, and filarial DNA in mosquitoes <0.25%. Community Mf and CFA prevalence rates ranged from 0-0.9% and 0-3.4%, respectively. Infection rates were significantly higher in males and lower in people who denied prior treatment. Antibody rates in school children exceeded 2% in 10 study sites; the area that had the highest community and school CFA rates also had the highest school antibody rate (6.9%). Filarial DNA rates in mosquitoes exceeded 0.25% in 10 PHI areas. Comprehensive surveillance is feasible for some national filariasis elimination programs. Low-level persistence of LF was present in all study sites; several sites failed to meet provisional endpoint criteria for LF elimination, and follow-up testing will be needed in these areas. TAS was not sensitive for detecting low-level persistence of filariasis in Sri Lanka. We recommend use of antibody and MX testing as tools to complement TAS for post

Human infection with sub-periodic Brugia spp. in Gampaha District, Sri Lanka: a threat to filariasis elimination status?

PubMed

Mallawarachchi, Chandana H; Nilmini Chandrasena, T G A; Premaratna, Ranjan; Mallawarachchi, S M N S M; de Silva, Nilanthi R

2018-01-29

Post-mass drug administration (MDA) surveillance during the lymphatic filariasis (LF) elimination program in Sri Lanka, revealed the re-emergence of brugian filariasis after four decades. This study was done with the objectives of investigating the epidemiology and age-specific vulnerability to infection. Surveillance was done using night blood smears (NBS) and the Brugia rapid test (BRT), to detect microfilaria (MF) and anti-Brugia IgG4 antibodies in blood samples collected from an age-stratified population enrolled from two high-risk study areas (SA)s, Pubudugama and Wedamulla in the Gampaha District. The periodicity of the re-emergent Brugia spp. was characterized by quantitative estimation of MF in blood collected periodically over 24 h using nucleopore-membrane filtration method. Of 994 participants [Pubudugama 467 (47.9%) and Wedamulla 527 (53%)] screened by NBS, two and zero cases were positive for MF at Pubudugama (MF rate, 0.43) and Wedamulla (MF rate, 0), respectively, with an overall MF rate of 0.2. Of the two MF positives, one participant had a W. bancrofti while the other had a Brugia spp. infection. Of 984 valid BRT test readings [Pubudugama (n = 461) and Wedamulla (n = 523)], two and seven were positive for anti-brugia antibodies by BRT at Pubudugama (antibody rate 0.43) and Wedamulla (antibody rate 1.34), respectively, with an overall antibody rate of 0.91. Both MF positives detected from SAs and two of three other Brugia spp. MF positives detected at routine surveillance by the National Anti-Filariasis Campaign (AFC) tested negative by the BRT. Association of Brugia spp. infections with age were not evident due to the low case numbers. MF was observed in the peripheral circulation throughout the day (subperiodic) with peak counts occurring at 21 h indicating nocturnal sub-periodicity. There is the low-level persistence of bancroftian filariasis and re-emergence of brugian filariasis in the Gampaha District, Sri Lanka. The periodicity

Evaluation of ICT filariasis card test using whole capillary blood: comparison with Knott's concentration and counting chamber methods.

PubMed

Njenga, S M; Wamae, C N

2001-10-01

An immunochromatographic card test (ICT) that uses fingerprick whole blood instead of serum for diagnosis of bancroftian filariasis has recently been developed. The card test was validated in the field in Kenya by comparing its sensitivity to the combined sensitivity of Knott's concentration and counting chamber methods. A total of 102 (14.6%) and 117 (16.7%) persons was found to be microfilaremic by Knott's concentration and counting chamber methods, respectively. The geometric mean intensities (GMI) were 74.6 microfilariae (mf)/ml and 256.5 mf/ml by Knott's concentration and counting chamber methods, respectively. All infected individuals detected by both Knott's concentration and counting chamber methods were also antigen positive by the ICT filariasis card test (100% sensitivity). Further, of 97 parasitologically amicrofilaremic persons, 24 (24.7%) were antigen positive by the ICT. The overall prevalence of antigenemia was 37.3%. Of 100 nonendemic area control persons, none was found to be filarial antigen positive (100% specificity). The results show that the new version of the ICT filariasis card test is a simple, sensitive, specific, and rapid test that is convenient in field settings.

Morbidity management and disability prevention for lymphatic filariasis in Sri Lanka: Current status and future prospects

PubMed Central

Premaratna, Ranjan; Gunaratna, Indeewarie. E.; de Silva, Nilanthi R.

2018-01-01

Background Sri Lanka was acknowledged to have eliminated lymphatic filariasis (LF) as a public health problem in 2016, largely due to its success in Mass Drug Administration (MDA) to interrupt disease transmission. Analysis of the Strengths, Weaknesses, Opportunities and Threats (SWOT) of the national Morbidity Management and Disability Prevention (MMDP) program, the other pillar of the LF control program, was carried out with the objective of evaluating it and providing recommendations to optimize the use of available resources. Methodology A situation analysis of the MMDP activities provided by the state health sector was carried out using published records, in-depth interviews with key informants of the Anti Filariasis Campaign, site-visits to filariasis clinics with informal discussions with clinic workforce and personal communications to identify strengths and weaknesses; and opportunities to overcome weaknesses and perceived threats to the program were explored. The principal strength of the MMDP program was the filariasis clinics operational in most endemic districts of Sri Lanka, providing free health care and health education to clinic attendees. The weaknesses identified were the low accessibility of clinics, incomplete coverage of the endemic region and lack of facilities for rehabilitation. The perceived threats were diversion of staff and resources for control of other vector-borne infections, under-utilization of clinics and non-compliance with recommended treatment. Enhanced high level commitment for MMDP, wider publicity and referral systems, integration of MMDP with other disease management services and collaboration with welfare organizations and research groups were identified as opportunities to overcome weaknesses and challenges. Conclusions The recommended basic package of MMDP was functional in most of the LF-endemic region. The highlighted weaknesses and challenges, unless addressed, may threaten program sustainability. The identified

Urban lymphatic filariasis.

PubMed

Simonsen, Paul E; Mwakitalu, Mbutolwe E

2013-01-01

Lymphatic filariasis (LF) is a disabling and disfiguring disease resulting from a mosquito-borne parasitic infection. It is a major public health problem in many countries with a warm climate. Research and control activities have mainly focused on LF in rural areas where it also has its major impact. However, with rapid and unplanned growth of cities in the developing world, there is a need also to consider LF transmission and control in urban settings. Here, we review currently available knowledge on urban LF and the environmental and socio-economic basis for its occurrence. Among the three parasite species causing LF in humans, only Wuchereria bancrofti has been documented to have a significant potential for urban transmission. This is primarily because one of its vectors, Culex quinquefasciatus, thrives and proliferates excessively in crowded city areas with poor sanitary, sewerage and drainage facilities. For this reason, urban LF also often shows a marked focality in distribution, with most cases clustered in areas inhabited by the less privileged city populations. More knowledge on urban LF is needed, in particular on its socio-economic and human behavioural context, on the potential for transmission in regions where other LF vector species predominate, and on rapid methods for identification and mapping of risk areas, to provide a strong evidence base for its control.

Lymphatic filariasis transmission risk map of India, based on a geo-environmental risk model.

PubMed

Sabesan, Shanmugavelu; Raju, Konuganti Hari Kishan; Subramanian, Swaminathan; Srivastava, Pradeep Kumar; Jambulingam, Purushothaman

2013-09-01

The strategy adopted by a global program to interrupt transmission of lymphatic filariasis (LF) is mass drug administration (MDA) using chemotherapy. India also followed this strategy by introducing MDA in the historically known endemic areas. All other areas, which remained unsurveyed, were presumed to be nonendemic and left without any intervention. Therefore, identification of LF transmission risk areas in the entire country has become essential so that they can be targeted for intervention. A geo-environmental risk model (GERM) developed earlier was used to create a filariasis transmission risk map for India. In this model, a Standardized Filariasis Transmission Risk Index (SFTRI, based on geo-environmental risk variables) was used as a predictor of transmission risk. The relationship between SFTRI and endemicity (historically known) of an area was quantified by logistic regression analysis. The quantified relationship was validated by assessing the filarial antigenemia status of children living in the unsurveyed areas through a ground truth study. A significant positive relationship was observed between SFTRI and the endemicity of an area. Overall, the model prediction of filarial endemic status of districts was found to be correct in 92.8% of the total observations. Thus, among the 190 districts hitherto unsurveyed, as many as 113 districts were predicted to be at risk, and the remaining at no risk. The GERM developed on geographic information system (GIS) platform is useful for LF spatial delimitation on a macrogeographic/regional scale. Furthermore, the risk map developed will be useful for the national LF elimination program by identifying areas at risk for intervention and for undertaking surveillance in no-risk areas.

Data reporting constraints for the lymphatic filariasis mass drug administration activities in two districts in Ghana: A qualitative study

PubMed Central

Aryeetey, Richmond; Boateng, Richard; Anto, Francis; Aikins, Moses; Gyapong, Margaret; Gyapong, John

2015-01-01

Objectives: Timely and accurate health data are important for objective decision making and policy formulation. However, little evidence exists to explain why poor quality routine health data persist. This study examined the constraints to data reporting for the lymphatic filariasis mass drug administration programme in two districts in Ghana. This qualitative study focused on timeliness and accuracy of mass drug administration reports submitted by community health volunteers. Methods: The study is nested within a larger study focusing on the feasibility of mobile phone technology for the lymphatic filariasis programme. Using an exploratory study design, data were obtained through in-depth interviews (n = 7) with programme supervisors and focus group discussions (n = 4) with community health volunteers. Results were analysed using thematic content analysis. Results: Reasons for delays in reporting were attributed to poor numeracy skills among community health volunteers, difficult physical access to communities, high supervisor workload, poor adherence reporting deadlines, difficulty in reaching communities within allocated time and untimely release of programme funds. Poor accuracy of data was mainly attributed to inadequate motivation for community health volunteers and difficulty calculating summaries. Conclusion: This study has shown that there are relevant issues that need to be addressed in order to improve the quality of lymphatic filariasis treatment coverage reports. Some of the factors identified are problems within the health system; others are specific to the community health volunteers and the lymphatic filariasis programme. Steps such as training on data reporting should be intensified for community health volunteers, allowances for community health volunteers should be re-evaluated and other non-monetary incentives should be provided for community health volunteers. PMID:26770791

Can Lymphatic Filariasis Be Eliminated by 2020?

PubMed

Rebollo, Maria P; Bockarie, Moses J

2017-02-01

Interventions against neglected tropical diseases (NTD), including lymphatic filariasis (LF), scaled up dramatically after the signing of the London Declaration (LD) in 2012. LF is targeted for elimination by 2020, but some countries are considered not on track to meet the 2020 target using the recommended preventive chemotherapy and morbidity management strategies. In this Opinion article we review the prospects for achieving LF elimination by 2020 in the light of the renewed global action against NTDs and the global efforts to achieve the sustainable development goals (SDGs) by 2030. We conclude that LF can be eliminated by 2020 using cross-sectoral and integrated approaches because of the compound effect of the other SDG activities related to poverty reduction and water and sanitation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Controlling lymphatic filariasis and soil-transmitted helminthiasis together in South Asia: opportunities and challenges

PubMed Central

Padmasiri, EA; Montresor, A; Biswas, G; de Silva, NR

2017-01-01

Summary Lymphatic filariasis (LF) and the major soil-transmitted helminth (STH) infections are co-endemic in many countries, particularly in Asia. Control strategies for both groups of infections have increasingly focused on the use of mass chemotherapy. With the use of albendazole, there is now a tool that is common to both. However, there are also important differences in their modes of transmission and epidemiology, and as a result, in the overall control strategies. The Global Programme for the Elimination of Lymphatic Filariasis aims to eliminate LF through time-limited, Mass Drug Administration programmes. STH control activities are more diffuse, aiming to piggy-back de-worming onto existing services such as school health activities; controlling morbidity, rather than eliminating infection, is the stated goal. In order to maximize health benefits to communities that are endemic for one or both of these infections, it is vitally important that policy makers and programme managers have a clear understanding of both commonalities and differences, and implement control programmes that allocate available resources in an optimal manner. PMID:16546228

Controlling lymphatic filariasis and soil-transmitted helminthiasis together in South Asia: opportunities and challenges.

PubMed

Padmasiri, E A; Montresor, A; Biswas, G; de Silva, N R

2006-09-01

Lymphatic filariasis (LF) and the major soil-transmitted helminth (STH) infections are co-endemic in many countries, particularly in Asia. Control strategies for both groups of infections have increasingly focused on the use of mass chemotherapy. With the use of albendazole, there is now a tool that is common to both. However, there are also important differences in their modes of transmission and epidemiology, and, as a result, in the overall control strategies. The Global Programme for the Elimination of Lymphatic Filariasis aims to eliminate LF through time-limited mass drug administration programmes. Control activities for STH are more diffuse, aiming to piggy-back de-worming onto existing services, such as school health activities; controlling morbidity, rather than eliminating infection, is the stated goal. In order to maximize health benefits to communities that are endemic for one or both of these infections, it is vitally important that policy makers and programme managers have a clear understanding of both commonalities and differences, and implement control strategies that allocate available resources in an optimal manner.

[Filariasis control: entry point for other helminthiasis control programs?].

PubMed

Boussinesq, M

2006-08-01

Filariasis control programs are based on a decentralized drug distribution strategy known as "community-directed". This strategy could also be applied to the control of schistosomiasis and intestinal nematode infections. Integration of these control programs could be highly cost-effective. However, as a prerequisite for integration, it would be necessary to identify zones where these helminthic infections co-exist, specify the population categories that should receive each medication (ivermectin, albendazole, mebendazole, and praziquantel), check that combined administration of these drugs is safe and ensure that an integrated program would have no detrimental effect on the health care system and on the efficacy of ongoing programs.

Control of bancroftian filariasis by cooking salt medicated with diethylcarbamazine

PubMed Central

Hawking, Frank; Marques, Ruy João

1967-01-01

In small-scale pilot trials, filarial infection can usually be reduced to low levels by oral administration of diethylcarbamazine to all the persons concerned; but in mass campaigns it is often difficult to persuade large numbers of people to swallow the tablets. In order to overcome this difficulty the authors propose that the compound be incorporated into cooking salt, as has been done with chloroquine to control malaria. There are many reasons why this method of medication should be more effective against filariasis than it has often been against malaria. Laboratory trials showed that cooking the compound in food did not make it toxic for rats or diminish its antifilarial activity. A pilot trial was carried out at Recife, Brazil, in which 1000 adults received salt containing 0.4% diethylcarbamazine (corresponding to a daily intake of 100 mg/day) for 40 days, and then salt containing 0.1% compound for a year. This medication was simple to administer; it was quite acceptable to the subjects; it caused no untoward effects; and it removed almost all the microfilariae from the blood. Administration of medicated salt (0.3%) for 18 days to another group of 1300 adults was well tolerated and produced a considerable reduction of the microfilarial load; but this short period was insufficient to remove all the microfilariae. The authors recommend that this method of administering diethylcarbamazine to large numbers of people should be investigated further to see if it could be used for mass campaigns to control filariasis. PMID:5301383

Strategies and tools for the control/elimination of lymphatic filariasis.

PubMed Central

Ottesen, E. A.; Duke, B. O.; Karam, M.; Behbehani, K.

1997-01-01

Lymphatic filariasis infects 120 million people in 73 countries worldwide and continues to be a worsening problem, especially in Africa and the Indian subcontinent. Elephantiasis, lymphoedema, and genital pathology afflict 44 million men, women and children; another 76 million have parasites in their blood and hidden internal damage to their lymphatic and renal systems. In the past, tools and strategies for the control of the condition were inadequate, but over the last 10 years dramatic research advances have led to new understanding about the severity and impact of the disease, new diagnostic and monitoring tools, and, most importantly, new treatment tools and control strategies. The new strategy aims both at transmission control through community-wide (mass) treatment programmes and at disease control through individual patient management. Annual single-dose co-administration of two drugs (ivermectin + diethylcarbamazine (DEC) or albendazole) reduces blood microfilariae by 99% for a full year; even a single dose of one drug (ivermectin or DEC) administered annually can result in 90% reductions; field studies confirm that such reduction of microfilarial loads and prevalence can interrupt transmission. New approaches to disease control, based on preventing bacterial superinfection, can now halt or even reverse the lymphoedema and elephantiasis sequelae of filarial infection. Recognizing these remarkable technical advances, the successes of recent control programmes, and the biological factors favouring elimination of this infection, the Fiftieth World Health Assembly recently called on WHO and its Member States to establish as a priority the global elimination of lymphatic filariasis as a public health problem. PMID:9509621

Central nervous system filariasis masquerading as a glioma: case report.

PubMed

Shrivastava, Adesh; Arora, Prateek; Khare, Akriti; Goel, Garima; Kapoor, Neelkamal

2017-09-01

Filariasis, an endemic zoonosis in the Southeast Asia region, has been reported to affect various organs as well as the central nervous system (CNS). Inflammatory reactions mimicking those from neoplastic lesions clinically and radiologically have been reported in the breast and urinary bladder. To date, a CNS manifestation of filarial infestation has been reported in the form of meningoencephalitis. The authors here present an interesting case of a young man presenting in status epilepticus, which on radiological evaluation appeared to be a glioma. However, postoperative histopathological examination changed the provisional diagnosis to a filarial infection of the CNS mimicking a primary CNS neoplasm.

Efficacy, Safety, and Pharmacokinetics of Coadministered Diethylcarbamazine, Albendazole, and Ivermectin for Treatment of Bancroftian Filariasis.

PubMed

Thomsen, Edward K; Sanuku, Nelly; Baea, Manasseh; Satofan, Samson; Maki, Elit; Lombore, Bart; Schmidt, Mark S; Siba, Peter M; Weil, Gary J; Kazura, James W; Fleckenstein, Lawrence L; King, Christopher L

2016-02-01

Available treatments for lymphatic filariasis (LF) are limited in their longterm clearance of microfilaria from the blood. The safety and efficacy of a single-dose triple-drug therapy of the antifilarial drugs diethylcarbamazine (DEC), ivermectin (IVM), and albendazole (ALB) for LF are unknown. We performed a pilot study to test the efficacy, safety, and pharmacokinetics of single-dose DEC, IVM, and ALB in Wuchereria bancrofti-infected Papua New Guineans. Adults were randomized into 2 treatment arms, DEC 6 mg/kg + ALB 400 mg (N = 12) or DEC 6 mg/kg + ALB 400 mg + IVM 200 μg/kg (N = 12), and monitored for microfilaria, parasite antigenemia, adverse events (AEs), and serum drug levels. Triple-drug therapy induced >2-log reductions in microfilaria levels at 36 and 168 hours after treatment compared with approximately 1-log reduction with 2 drugs. All 12 individuals who received 3 drugs were microfilaria negative 1 year after treatment, whereas 11 of 12 individuals in the 2-drug regimen were microfilaria positive. In 6 participants followed 2 years after treatment, those who received 3 drugs remained microfilaria negative. AEs, particularly fever, myalgias, pruritus, and proteinuria/hematuria, occurred in 83% vs 50% of those receiving triple-drug compared to 2-drug treatment respectively (P = .021); all resolved within 7 days after treatment. No serious AEs were observed in either group. There was no significant effect of IVM on DEC or ALB drug levels. Triple-drug therapy is safe and more effective than DEC + ALB for Bancroftian filariasis and has the potential to accelerate elimination of lymphatic filariasis. NCT01975441. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Transmission models and management of lymphatic filariasis elimination.

PubMed

Michael, Edwin; Gambhir, Manoj

2010-01-01

The planning and evaluation of parasitic control programmes are complicated by the many interacting population dynamic and programmatic factors that determine infection trends under different control options. A key need is quantification about the status of the parasite system state at any one given timepoint and the dynamic change brought upon that state as an intervention program proceeds. Here, we focus on the control and elimination of the vector-borne disease, lymphatic filariasis, to show how mathematical models of parasite transmission can provide a quantitative framework for aiding the design of parasite elimination and monitoring programs by their ability to support (1) conducting rational analysis and definition of endpoints for different programmatic aims or objectives, including transmission endpoints for disease elimination, (2) undertaking strategic analysis to aid the optimal design of intervention programs to meet set endpoints under different endemic settings and (3) providing support for performing informed evaluations of ongoing programs, including aiding the formation of timely adaptive management strategies to correct for any observed deficiencies in program effectiveness. The results also highlight how the use of a model-based framework will be critical to addressing the impacts of ecological complexities, heterogeneities and uncertainties on effective parasite management and thereby guiding the development of strategies to resolve and overcome such real-world complexities. In particular, we underscore how this approach can provide a link between ecological science and policy by revealing novel tools and measures to appraise and enhance the biological controllability or eradicability of parasitic diseases. We conclude by emphasizing an urgent need to develop and apply flexible adaptive management frameworks informed by mathematical models that are based on learning and reducing uncertainty using monitoring data, apply phased or sequential

Cost-effective antigen testing for delimitation, monitoring and evaluation in bancroftian filariasis.

PubMed

Das, L K; Pani, S P; Vanamail, P; Vijayalakshmi, G; Debritto, L J

2012-01-31

This study was focussed on identifying a cost-effective method for delimitation, monitoring and evaluation in bancroftian filariasis. Finger prick blood samples were collected between 20.00 and 23.00 hours for the detection of microfilariae (mf) from the available population in a village which was endemic for lymphatic filariasis. Simultaneously, from each individual, four spots of 25-μl blood samples were collected on Whatman number 3 filter paper and air dried. Dried filter paper spots were pooled in quantities of 1, 5, 10, 15, 20 and 25 on unknown and simulated mf and antigen prevalence. Pooled samples were assayed for circulating filarial antigen (CFA) using TropBIO Og4C3 ELISA kits. The community mf and CFA rates were 3.4% and 25.9%, respectively. The pool sizes of 20 and 25 showed CFA positivity in all the above categories tested. The results of the pooled blood spot samples suggest that, in areas with mf and CFA prevalence rates between 1 and 10%, pools of 20 or 25 could be considered as the ideal pool size for the detection of filarial infection in the community. CFA prevalence at the level of 5-6% following desirable rounds of mass drug administration (MDA) indicates that the community mf prevalence is likely to be at the 1% level.

COMMUNITY MEMBERS' PERCEPTIONS OF MASS DRUG ADMINISTRATION FOR CONTROL OF LYMPHATIC FILARIASIS IN RURAL AND URBAN TANZANIA.

PubMed

Kisoka, William J; Tersbøl, Britt Pinkowsky; Meyrowitsch, Dan W; Simonsen, Paul E; Mushi, Declare L

2016-01-01

Lymphatic filariasis is one of several neglected tropical diseases with severely disabling and stigmatizing manifestations that are referred to as 'neglected diseases of poverty'. It is a mosquito-borne disease found endemically and exclusively in low-income contexts where, concomitantly, general public health care is often deeply troubled and fails to meet the basic health needs of impoverished populations. This presents particular challenges for the implementation of mass drug administration (MDA), which currently is the principal means of control and eventual elimination. Several MDA programmes face the dilemma that they are unable to attain and maintain the required drug coverage across target groups. In recognition of this, a qualitative study was conducted in the Morogoro and Lindi regions of Tanzania to gain an understanding of community experiences with, and perceptions of, the MDA campaign implemented in 2011 by the National Lymphatic Filariasis Elimination Programme. The study revealed a wide variation of perceptions and experiences regarding the aim, rationale and justification of MDA. There were positive sentiments about the usefulness of the drugs, but many study participants were sceptical about the manner in which MDA is implemented. People were particularly disappointed with the limited attempts by implementers to share information and mobilize residents. In addition, negative sentiments towards MDA for lymphatic filariasis reflected a general feeling of desertion and marginalization by the health care system and political authorities. However, the results suggest that if the communities are brought on board with genuine respect for their integrity and informed self-determination, there is scope for major improvements in community support for MDA-based control activities.

Lymphatic filariasis and associated morbidities in rural communities of Ogun State, Southwestern Nigeria.

PubMed

Christiana, Okonofua; Olajumoke, Morenikeji; Oyetunde, Salawu

2014-01-01

Lymphatic filariasis caused by Wuchereria bancrofti is a serious public health problem in rural communities of Nigeria. The study assessed the prevalence of lymphatic filariasis and associated clinical morbidities in Ado-Odo Ota Local Government Area of Ogun State. Microscopic examination of thick blood smears of 500 participants of both sexes and age ranging from 1 to 79 years was conducted. Visual observations of clinical manifestations of chronic infection were also conducted. The overall prevalence and intensity of infection were 21% and 21.4 mf/mL of blood respectively. Microfilaraemic prevalence was significantly higher in males (27.1%) than in females (16%) (P < 0.001). However, intensity of infection was not gender and age dependent (P > 0.05). The overall prevalence of all clinical manifestations of infection due to W. bancrofti is 15% with hydrocele, limb and breast elephantiasis constituting 16.9%, 4.6% and 5.1% of the total population respectively. Prevalence of hydrocele and limb elephantiasis was significantly higher in the older age groups (P < 0.05). Occurrence of elephantiasis of the breast in women however was not associated with age (P > 0.05). Integrated approach through chemotherapy and vector control is therefore advocated to reduce morbidity due to infection in this study area. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of Methods for Xenomonitoring in Vectors of Lymphatic Filariasis in Northeastern Tanzania

PubMed Central

Irish, Seth R.; Stevens, William M. B.; Derua, Yahya A.; Walker, Thomas; Cameron, Mary M.

2015-01-01

Monitoring Wuchereria bancrofti infection in mosquitoes (xenomonitoring) can play an important role in determining when lymphatic filariasis has been eliminated, or in focusing control efforts. As mosquito infection rates can be low, a method for collecting large numbers of mosquitoes is necessary. Gravid traps collected large numbers of Culex quinquefasciatus in Tanzania, and a collection method that targets mosquitoes that have already fed could result in increased sensitivity in detecting W. bancrofti-infected mosquitoes. The aim of this experiment was to test this hypothesis by comparing U.S. Centers for Disease Control and Prevention (CDC) light traps with CDC gravid traps in northeastern Tanzania, where Cx. quinquefasciatus is a vector of lymphatic filariasis. After an initial study where small numbers of mosquitoes were collected, a second study collected 16,316 Cx. quinquefasciatus in 60 gravid trap-nights and 240 light trap-nights. Mosquitoes were pooled and tested for presence of W. bancrofti DNA. Light and gravid traps collected similar numbers of mosquitoes per trap-night, but the physiological status of the mosquitoes was different. The estimated infection rate in mosquitoes collected in light traps was considerably higher than in mosquitoes collected in gravid traps, so light traps can be a useful tool for xenomonitoring work in Tanzania. PMID:26350454

Prediction of Brugia malayi antigenic peptides: candidates for synthetic vaccine design against lymphatic filariasis.

PubMed

Gomase, Virendra S; Chitlange, Nikhilkumar R; Changbhale, Smruti S; Kale, Karbhari V

2013-08-01

Brugia malayi is a threadlike nematode cause's swelling of lymphatic organs, condition well known as lymphatic filariasis; till date no invention made to effectively address lymphatic filariasis. In this analysis we a have predicted suitable antigenic peptides from Brugia malayi antigen protein for peptide vaccine design against lymphatic filariasis based on cross protection phenomenon as, an ample immune response can be generated with a single protein subunit. We found MHC class II binding peptides of Brugia malayi antigen protein are important determinant against the diseased condition. The analysis shows Brugia malayi antigen protein having 505 amino acids, which shows 497 nonamers. In this assay, we have predicted MHC-I binding peptides for 8mer_H2_Db (optimal score- 15.966), 9mer_H2_Db (optimal score- 15.595), 10mer_H2_Db (optimal score- 19.405), 11mer_H2_Dballeles (optimal score- 23.801). We also predicted the SVM based MHCII-IAb nonamers, 51-FQQIDPLDA, 442-FAAIACLVH, 206-YLNPFGHQF, 167-WYVIMAACY, 367-YAMIVIRLL, 434- LVITTAANF, 176-LDSYCLWKP, 435-VITTAANFA, 364-WPGYAMIVI (optimal score- 13.963); MHCII-IAd nonamers, 52-QQIDPLDAE, 171-MAACYLDSY, 239-QWRSVILCN, 168-YVIMAACYL, 3-QYLSVHSLS, 322-EILLHAKVV, 417- LGIIASFVS, 396-KAIFLAHFG, 167-WYVIMAACY, 269-LALHCINVI, 93-FINKAAPKQ, 259-NCIIVLKAF, 79- QGVLLIIPR, 22-TILQRSQAI, 63-RGFVYGNVS, 109-NISSLAFET,(optimal score- 16.748); and MHCII-IAg7 nonamers 171-MAACYLDSY, 73-KIVNGAQGV, 259-NCIIVLKAF, 209-PFGHQFSFE, 102-SCDTLLKNI, 25-QRSQAIRIV, 444- AIACLVHLF, 88-SLVNGFINK, 252-FPRHQLLNC, 471-RFVLANDNE, 52-QQIDPLDAE, 469-HRRFVLAND, 457- SNRHYFLAD, 362-KSWPGYAMI, 476-NDNEGEDFE, 370-IVIRLLQAL (optimal score- 19.847) which represents potential binders from Brugia malayi antigen protein. The method integrates prediction of MHC class I binding proteasomal C-terminal cleavage peptides and Eighteen potential antigenic peptides at average propensity 1.063 having highest local hydrophilicity. Thus a small antigen fragment can induce

Economic Costs and Benefits of a Community-Based Lymphedema Management Program for Lymphatic Filariasis in Odisha State, India

PubMed Central

Stillwaggon, Eileen; Sawers, Larry; Rout, Jonathan; Addiss, David; Fox, LeAnne

2016-01-01

Lymphatic filariasis afflicts 68 million people in 73 countries, including 17 million persons living with chronic lymphedema. The Global Programme to Eliminate Lymphatic Filariasis aims to stop new infections and to provide care for persons already affected, but morbidity management programs have been initiated in only 24 endemic countries. We examine the economic costs and benefits of alleviating chronic lymphedema and its effects through a simple limb-care program. For Khurda District, Odisha State, India, we estimated lifetime medical costs and earnings losses due to chronic lymphedema and acute dermatolymphangioadenitis (ADLA) with and without a community-based limb-care program. The program would reduce economic costs of lymphedema and ADLA over 60 years by 55%. Savings of US$1,648 for each affected person in the workforce are equivalent to 1,258 days of labor. Per-person savings are more than 130 times the per-person cost of the program. Chronic lymphedema and ADLA impose a substantial physical and economic burden on the population in filariasis-endemic areas. Low-cost programs for lymphedema management based on limb washing and topical medication for infection are effective in reducing the number of ADLA episodes and stopping progression of disabling and disfiguring lymphedema. With reduced disability, people are able to work longer hours, more days per year, and in more strenuous, higher-paying jobs, resulting in an important economic benefit to themselves, their families, and their communities. Mitigating the severity of lymphedema and ADLA also reduces out-of-pocket medical expense. PMID:27573626

The Effect of Compliance on the Impact of Mass Drug Administration for Elimination of Lymphatic Filariasis in Egypt

PubMed Central

El-Setouhy, Maged; Abd Elaziz, Khaled M.; Helmy, Hanan; Farid, Hoda A.; Kamal, Hussein A.; Ramzy, Reda M. R.; Shannon, William D.; Weil, Gary J.

2008-01-01

We studied effects of compliance on the impact of mass drug administration (MDA) with diethylcarbamazine and albendazole for lymphatic filariasis (LF) in an Egyptian village. Baseline microfilaremia (mf) and filarial antigenemia rates were 11.5% and 19.0%, respectively. The MDA compliance rates were excellent (> 85%). However, individual compliance was highly variable; 7.4% of those surveyed after five rounds of MDA denied having ever taken the medications and 52.4% reported that they had taken all five doses. The mf and antigenemia rates were 0.2% and 2.7% in those who reported five doses of MDA and 8.3% and 13.8% in those who reported zero doses. There was no significant difference in residual infection rates among those who had taken two or more doses. These results underscore the importance of compliance for LF elimination programs based on MDA and suggest that two ingested doses of MDA are as effective as five doses for reducing filariasis infection rates. PMID:18165524

Brugia filariasis differentially modulates persistent Helicobacter pylori gastritis in the gerbil model

PubMed Central

Martin, Heather R.; Shakya, Krishna P.; Muthupalani, Sureshkumar; Ge, Zhongming; Klei, Thomas R.; Whary, Mark T.; Fox, James G.

2011-01-01

In select Helicobacter pylori-infected populations with low gastric cancer, nematode coinfections are common and both helicobacter gastritis and filariasis are modeled in gerbils. We evaluated gastritis, worm counts, tissue cytokine gene expression levels and Th1/Th2-associated antibody responses in H. pylori and Brugia pahangi mono- and coinfected gerbils. H. pylori-associated gastritis indices were significantly lower 21 weeks post-infection in coinfected gerbils (p ≤ 0.05) and were inversely proportional to worm counts (r2 = −0.62, p < 0.003). Additionally, IFN-γ, IL-1β, CXCL1, IL-4 and IL-10 mRNA levels in the gastric antrum reflected a significant host response to gastric H. pylori and as well as systemic filariasis (p ≤ 0.05). Despite increasing worm burden (p < 0.05), gastritis progressed in coinfected gerbils (p < 0.03) becoming equivalent to H. pylori-infected gerbils at 42 weeks (p = 0.7). Pro- and anti-inflammatory mediator mRNA levels were notably downregulated in B. pahangi infected gerbils below uninfected control values, suggesting hyporesponsiveness to B. pahangi. Consistent with an increasing Th1 response to H. pylori, IgG2a (p < 0.01), IL-1β (p = 0.04) and CXCL1 (p = 0.006) responses significantly increased and IL-4 (p = 0.05) and IL-10 (p = 0.04) were decreased in coinfected gerbils at 42 weeks. Initial systemic responses to B. pahangi resulted in attenuated gastritis in coinfected gerbils, but subsequent filarid-associated hyporesponsiveness appears to have promoted H. pylori gastritis. PMID:20685294

Spatial analysis of lymphatic filariasis distribution in the Nile Delta in relation to some environmental variables using geographic information system technology.

PubMed

Hassan, A N; Dister, S; Beck, L

1998-04-01

Geographic information system (GIS) was used to analyze the spatial distribution of filariasis in the Nile Delta. The study involved 201 villages belonging to Giza, Qalubiya, Monoufiya, Gharbiya, and Dakahliya governorates. Villages with similar microfilarial (mf) prevalence rates were observed to cluster within 1-2 km distance, then, clustering started to decrease significantly with distance up to 5 km (Pearson correlation coefficient = -0.98). the likelihood of negative and high prevalence villages being contiguous was very low (approximately 1.8%, n = 612 village-pairs) indicating homogeneity in disease processes within the defined spatial scales. Of the villages located within 2 km from the main Nile branches (n = 46), 95% exhibited low prevalence. In addition, the spatial pattern of mf prevalence was shown to be negatively associated with annual rainfall and relative humidity, while it was positively associated with annual daily temperature. Average mf prevalence in warmer, relatively drier areas receiving 25 mm of rain was significantly higher (3.9%) than that in less warmer but more humid areas receiving 50 mm of rain (1.6%) (P < 0.0001). Based on the results of the present study, GIS was used to generate a "filariasis risk map" that could be used by health authorities to efficiently direct surveillance and control efforts. This investigation identified some of the factors underlying filariasis spatial pattern, quantified clustering and demonstrated the potential of GIS application in vector-borne disease epidemiology.

Soil transmitted helminths and scabies in Zanzibar, Tanzania following mass drug administration for lymphatic filariasis - a rapid assessment methodology to assess impact

PubMed Central

2012-01-01

Background Ivermectin and albendazole are used in annual mass drug administration (MDA) for the lymphatic filariasis elimination programmes in African countries co-endemic for onchocerciasis, but have additional impact on soil transmitted helminths and the ectoparasitic mite which causes scabies. Assessing these collateral impacts at scale is difficult due to the insensitivity of available parasite detection techniques. Methods The numbers of cases diagnosed with intestinal helminths and scabies and who received prescriptions for treatment were evaluated in 50 health centres in Zanzibar. Records were examined from 2000, prior to the initiation of MDA to 2005, after six rounds of MDA for lymphatic filariasis had taken place. Results Health centre records showed a consistent decline in the number of cases of intestinal helminths and scabies diagnosed by community health workers in Zanzibar and the number of prescriptions issued across five age groups. A 90-98% decline in soil transmitted helminths and 68-98% decline in scabies infections were recorded. Poisson regression models aggregated to both the island-level and district-level indicated that the decline was statistically significant. Conclusions The described method of examining health centre records has the potential for use on a large scale, despite limitations, as a rapid method to evaluate the impacts resulting from both lymphatic filariasis and onchocerciasis MDA. This would result in a reduction in the need for parasitological evaluations to determine prevalence and intensity. PMID:23259465

Coverage and Awareness of and Compliance with Mass Drug Administration for Elimination of Lymphatic Filariasis in Burdwan District, West Bengal, India

PubMed Central

Sarkar, Aditya Prasad; Misra, Raghunath; Chakroborty, Amitava; Mondal, Tusar Kanti; Bag, Kanad

2013-01-01

India adopted WHO's strategy of repeated rounds of mass drug administration (MDA) with diethylcarbamazine to eliminate lymphatic filariasis. The present study attempted to assess the coverage and awareness of and compliance with MDA for elimination of lymphatic filariasis in Burdwan district of India, following MDA round in July 2010. A cross-sectional study was conducted among the four randomly-selected clusters in the district of Burdwan, West Bengal, India, covering 603 individuals from 154 households, using a predesigned pretested schedule. The drug distribution coverage, compliance, and effective coverage were 48.76 %, 70.07%, and 34.16% respectively. Only 41.4% of the study population was aware of the MDA activity. This evaluation study noted that MDA is restricted to tablet distribution only. There is an urgent need to improve compliance with drug intake through strengthening of the awareness programme involving both government health workers and community volunteers. PMID:23930334

Rapid assessment of the geographical distribution of lymphatic filariasis in Uganda, by screening of schoolchildren for circulating filarial antigens.

PubMed

Onapa, A W; Simonsen, P E; Baehr, I; Pedersen, E M

2005-03-01

To permit improvements in the targeting of control activities, the geographical distribution of lymphatic filariasis in Uganda was assessed by using a rapid immunochromatographic card test to check school-aged children for Wuchereria bancrofti-specific circulating filarial antigens (CFA). Survey sites were selected to represent the various ecological and topographical diversities in the country. Overall, 17,533 children from 76 sites were examined. CFA-positive cases were detected at 31 of the sites, with prevalences ranging from 0.4% to 30.7%. There appeared to be strikingly more lymphatic filariasis in the north of the country than in the south. The main focus was north of the Victoria Nile, where 27 (66%) of 41 sites had CFA-positive cases, often at high prevalences. Only four (11.4%) of the 35 sites south of the Victoria Nile had CFA-positive cases, and all four were along the western rift valley and had relatively low CFA prevalences. Geostatistical interpolation was used to create a map showing the geographical distribution of CFA prevalences in Uganda (by ordinary kriging), and to assess the population exposed to W. bancrofti transmission. Estimates based on population data from 2002 indicated that approximately 8.7 million people (35.3% of the national population) lived in areas where > 1% of the school-aged children were CFA-positive. CFA prevalences generally decreased with increasing altitude, and no CFA-positive cases were found at sites that were > 1300 m above sea level. Although it gives an under-estimate of the overall community prevalence (a fact that should be taken into account when interpreting the present results and comparing them with the results of other surveys), the screening of schoolchildren for CFA was found to be a simple and useful approach for mapping the geographical distribution of lymphatic filariasis.

Surveillance efforts after mass drug administration to validate elimination of lymphatic filariasis as a public health problem in Vanuatu.

PubMed

Taleo, Fasihah; Taleo, George; Graves, Patricia M; Wood, Peter; Kim, Sung Hye; Ozaki, Masayo; Joseph, Hayley; Chu, Brian; Pavluck, Alex; Yajima, Aya; Melrose, Wayne; Ichimori, Kazuyo; Capuano, Corinne

2017-01-01

Vanuatu was formerly highly endemic for lymphatic filariasis (LF), caused by Wuchereria bancrofti and transmitted by Anopheles mosquitoes. After a baseline survey showing 4.8% antigen prevalence in 1998, the country conducted nationwide (in one implementation unit) annual mass drug administration (MDA) with albendazole and diethylcarbamazine citrate from 2000 to 2004 and achieved prevalence of 0.2% by 2006 in a representative nationwide cluster survey among all age groups. Post MDA surveillance was conducted from 2006 to 2012. After MDA, the country was divided for surveillance into three evaluation units (EUs) formed by grouping provinces according to baseline prevalence: EU1: Torba, Sanma and Malampa; EU2: Penama; EU3: Shefa and Tafea. The study compiled all past data and information on surveys in Vanuatu from the country programme. This paper reviews the surveillance activities done after stopping MDA to validate the interruption of transmission and elimination of LF as a public health problem. Post-MDA surveillance consisting of at least three transmission assessment surveys (TAS) in each of the three EUs was conducted between 2006 and 2012. Sentinel and spot check surveys identified a few villages with persistent high prevalence; all antigen positive cases in these sites were treated and additional targeted MDA conducted for 3 years in 13 villages in one area of concern. All three EUs passed all TAS in 2007, 2010 and 2012 respectively, with no positives found except in EU2 (Penama province) in 2012 when 2 children tested positive for circulating filariasis antigen. Assessment of the burden of chronic filariasis morbidity found 95 cases in 2003 and 32 remaining cases in 2007, all aged over 60 years. Vanuatu has achieved validation of elimination of LF as a public health problem. Post-validation surveillance is still recommended especially in formerly highly endemic areas.

Prevalence of Neglected Tropical Diseases (Leishmaniasis and Lymphatic Filariasis) and Malaria Among a Migrant Labour Settlement in Kerala, India.

PubMed

George, Sobha; Joy, Teena Mary; Kumar, Anil; Panicker, K N; George, Leyanna Susan; Raj, Manu; Leelamoni, K; Nair, Prem

2018-06-02

Neglected tropical diseases (visceral leismaniasis, lymphatic filariasis) and malaria are endemic in northern states of India. Kerala has become a hub of construction activities employing a large number of migrants from these endemic states. Studies on morbidity pattern among migrants in Kerala are lacking. It is essential to look into the burden of these infections among migrant laborers who can act as reservoirs and are a threat to native population. A cross sectional study was done among migrant laborers in Ernakulam district, Kerala. After getting informed consent, a questionnaire was administered to each participant to collect sociodemographic details and 5 ml of blood was collected for detection of antigens using rapid diagnostic tests (RDT). Of the 309 migrants tested, none of them were positive for leishmaniasis, while 3.8% were positive for malaria and 3.6% for filariasis. With 2.5 million migrant laborers in Kerala, the magnitude of the problem in absolute numbers is enormous. Active surveillance and treatment is needed to prevent the reemergence of these diseases in Kerala.

Recombinant antigen-based antibody assays for the diagnosis and surveillance of lymphatic filariasis – a multicenter trial

PubMed Central

Lammie, Patrick J; Weil, Gary; Noordin, Rahmah; Kaliraj, Perumal; Steel, Cathy; Goodman, David; Lakshmikanthan, Vijaya B; Ottesen, Eric

2004-01-01

The development of antifilarial antibody responses is a characteristic feature of infection with filarial parasites. It should be possible to exploit this fact to develop tools to monitor the progress of the global program to eliminate lymphatic filariasis (LF); however, assays based on parasite extracts suffer from a number of limitations, including the paucity of parasite material, the difficulty of assay standardization and problems with assay specificity. In principle, assays based on recombinant filarial antigens should address these limitations and provide useful tools for diagnosis and surveillance of LF. The present multicenter study was designed to compare the performance of antibody assays for filariasis based on recombinant antigens Bm14, WbSXP, and BmR1. Coded serum specimens were distributed to five participating laboratories where assays for each antigen were conducted in parallel. Assays based on Bm14, WbSXP, or BmR1 demonstrated good sensitivity (>90%) for field use and none of the assays demonstrated reactivity with specimens from persons with non-filarial helminth infections. Limitations of the assays are discussed. Well-designed field studies are now needed to assess sampling methodology and the application of antibody testing to the monitoring and surveillance of LF elimination programs. PMID:15347425

How effective is integrated vector management against malaria and lymphatic filariasis where the diseases are transmitted by the same vector?

PubMed

Stone, Christopher M; Lindsay, Steve W; Chitnis, Nakul

2014-12-01

The opportunity to integrate vector management across multiple vector-borne diseases is particularly plausible for malaria and lymphatic filariasis (LF) control where both diseases are transmitted by the same vector. To date most examples of integrated control targeting these diseases have been unanticipated consequences of malaria vector control, rather than planned strategies that aim to maximize the efficacy and take the complex ecological and biological interactions between the two diseases into account. We developed a general model of malaria and LF transmission and derived expressions for the basic reproductive number (R0) for each disease. Transmission of both diseases was most sensitive to vector mortality and biting rate. Simulating different levels of coverage of long lasting-insecticidal nets (LLINs) and larval control confirms the effectiveness of these interventions for the control of both diseases. When LF was maintained near the critical density of mosquitoes, minor levels of vector control (8% coverage of LLINs or treatment of 20% of larval sites) were sufficient to eliminate the disease. Malaria had a far greater R0 and required a 90% population coverage of LLINs in order to eliminate it. When the mosquito density was doubled, 36% and 58% coverage of LLINs and larval control, respectively, were required for LF elimination; and malaria elimination was possible with a combined coverage of 78% of LLINs and larval control. Despite the low level of vector control required to eliminate LF, simulations suggest that prevalence of LF will decrease at a slower rate than malaria, even at high levels of coverage. If representative of field situations, integrated management should take into account not only how malaria control can facilitate filariasis elimination, but strike a balance between the high levels of coverage of (multiple) interventions required for malaria with the long duration predicted to be required for filariasis elimination.

Prevalence of depression and associated clinical and socio-demographic factors in people living with lymphatic filariasis in Plateau State, Nigeria.

PubMed

Obindo, James; Abdulmalik, Jibril; Nwefoh, Emeka; Agbir, Michael; Nwoga, Charles; Armiya'u, Aishatu; Davou, Francis; Maigida, Kurkat; Otache, Emmanuel; Ebiloma, Ajuma; Dakwak, Samuel; Umaru, John; Samuel, Elisha; Ogoshi, Christopher; Eaton, Julian

2017-06-01

Lymphatic filariasis is a chronic, disabling and often disfiguring condition that principally impacts the world's poorest people. In addition to the well-recognised physical disability associated with lymphedema and hydrocele, affected people often experience rejection, stigma and discrimination. The resulting emotional consequences are known to impact on the quality of life and the functioning of the affected individuals. However, the management of this condition has focused on prevention and treatment through mass drug administration, with scant attention paid to the emotional impact of the condition on affected individuals. This study aimed to determine the prevalence and severity of depression among individuals with physical disfigurement from lymphatic filariasis in Plateau State, Nigeria. A cross-sectional 2-stage convenience study was conducted at 5 designated treatment centers across Plateau State, Nigeria. All available and consenting clients with clearly visible physical disfigurement were recruited. A semi-structured socio-demographic questionnaire, Rosenberg Self-esteem and a 9-item Patient Health Questionnaire (PHQ-9) were administered at the first stage. Those who screened positive (with a PHQ-9 score of five and above) were further interviewed using the Depression module of the Composite International Diagnostic Interview (CIDI). Ninety-eight individuals met the criteria and provided consent. Twenty percent of the respondents met criteria for depression, with the following proportions based on severity: Mild (42.1%), Moderate (31.6%) and Severe (26.3%). History of mental illness (OR 40.83, p = 0.008); Median duration of the illness was 17 years (IQR 7.0-30 years) and being unemployed (OR 12.71, p = 0.003) were predictive of depression. High self-esteem was negatively correlated (OR 0.09, p<0.004). Prevalence of depression is high among individuals with lymphatic filariasis and depression in sufferers is associated with low self-esteem and low levels

Prediction of villages at risk for filariasis transmission in the Nile Delta using remote sensing and geographic information system technologies.

PubMed

Hassan, A N; Beck, L R; Dister, S

1998-04-01

Remote sensing and geographic information system (GIS) technologies were used to discriminate between 130 villages, in the Nile Delta, at high and low risk for filariasis, as defined by microfilarial prevalence. Landsat Thematic Mapper (TM) data were digitally processed to generate a map of landcover as well as spectral indices such as NDVI and moisture index. A Tasseled Cap transformation was also carried out on the TM data which produced three more indices: brightness, greenness and wetness. GIS functions were used to extract information on landcover and spectral indices within one km buffers around the study villages. The relationship between satellite data and prevalence was investigated using discriminant analysis. The analysis indicated that the most important landscape elements associated with prevalence were water and marginal vegetation, while wetness and moisture index were the most important indices. Discriminant functions generated for these variables were able to correctly predict 80% and 74% of high and low prevalence villages, respectively, with an overall accuracy of 77%. The present approach provides a promising tool for regional filariasis surveillance and helps direct control efforts.

Assessing Progress in Reducing the At-Risk Population after 13 Years of the Global Programme to Eliminate Lymphatic Filariasis

PubMed Central

Hooper, Pamela J.; Chu, Brian K.; Mikhailov, Alexei; Ottesen, Eric A.; Bradley, Mark

2014-01-01

Background In 1997, the World Health Assembly adopted Resolution 50.29, committing to the elimination of lymphatic filariasis (LF) as a public health problem, subsequently targeted for 2020. The initial estimates were that 1.2 billion people were at-risk for LF infection globally. Now, 13 years after the Global Programme to Eliminate Lymphatic Filariasis (GPELF) began implementing mass drug administration (MDA) against LF in 2000—during which over 4.4 billion treatments have been distributed in 56 endemic countries—it is most appropriate to estimate the impact that the MDA has had on reducing the population at risk of LF. Methodology/Principal Findings To assess GPELF progress in reducing the population at-risk for LF, we developed a model based on defining reductions in risk of infection among cohorts of treated populations following each round of MDA. The model estimates that the number of people currently at risk of infection decreased by 46% to 789 million through 2012. Conclusions/Significance Important progress has been made in the global efforts to eliminate LF, but significant scale-up is required over the next 8 years to reach the 2020 elimination goal. PMID:25411843

Lymphatic filariasis in Peninsular Malaysia: a cross-sectional survey of the knowledge, attitudes, and practices of residents.

PubMed

Al-Abd, Nazeh M; Nor, Zurainee Mohamed; Ahmed, Abdulhamid; Al-Adhroey, Abdulelah H; Mansor, Marzida; Kassim, Mustafa

2014-11-27

Lymphatic filariasis (LF) is a major cause of permanent disability in many tropical and sub-tropical countries of the world. Malaysia is one of the countries in which LF is an endemic disease. Five rounds of the mass drug administration (MDA) program have been conducted in Malaysia as part of the Global Program to Eliminate Lymphatic Filariasis (GPELF) by year 2020. This study investigated the level of awareness of LF and the MDA program in a population living in an endemic area of the country. A descriptive cross-sectional survey that involved 230 respondents (≥15 years old) living in the LF endemic communities of Terengganu state in Peninsular Malaysia was performed. Demographic, socioeconomic, and knowledge, attitudes and practices (KAP) data of the respondents were obtained using pre-tested questionnaires and were analyzed using SPSS software version 13.0. More than 80% of the respondents were aware of LF and the common symptoms of the disease. Moreover, about 70% of the respondents that were aware of LF indicated that it is a problematic disease. Approximately 77% of the respondents indicated that filariasis is transmitted by mosquitoes. Two-thirds of respondents preferred hospital treatment for illness; however, only 12% had participated and/or received treatment for LF during an MDA program. Only 35% of the respondents that participated in this research were aware of the MDA program that had taken place in the area. None of the respondents had knowledge of the drug used in the treatment of LF. The findings from this research indicated that there was no significant association between LF awareness and with gender, age group, educational status, occupation, or socio-economic status of the respondents (P >0.05). A good proportion of the respondents are aware of LF, its mode of transmission and symptoms, however they demonstrated a poor knowledge of MDA which took place in the study area. For greater understanding of LF in the Malaysian population, there is a

Impact of Education Campaign on Community-Based Vector Control in Hastening the Process of Elimination of Lymphatic Filariasis in Tamil Nadu, South India

ERIC Educational Resources Information Center

Nandha, B.; Krishnamoorthy, K.

2012-01-01

Globally mosquito-borne lymphatic filariasis (LF) is targeted for elimination by 2020. Towards this goal, the scope of community-based vector control as a supplementary strategy to mass drug administration (MDA) was assessed through an intensive education campaign and evaluated using pre- and post-educational surveys in an intervention and…

Community-wide reduction in prevalence and intensity of intestinal helminths as a collateral benefit of lymphatic filariasis elimination programs.

PubMed

De Rochars, Madsen Beau; Direny, Abdel N; Roberts, Jacquelin M; Addiss, David G; Radday, Jeanne; Beach, Michael J; Streit, Thomas G; Dardith, Desire; Lafontant, Jack Guy; Lammie, Patrick J

2004-10-01

Annual mass treatment with antifilarial drugs is the cornerstone of the global program to eliminate lymphatic filariasis (LF). Although the primary goal of the program is to interrupt transmission of LF, additional public health benefits also are expected because of the known anthelminthic properties of these drugs. Since rapid re-infection with intestinal helminths occurs following treatment, annual de-worming may not be sufficient to produce a lasting reduction in the prevalence and intensity of these infections. We conducted stool examinations in four sentinel communities before and approximately nine months after each of two rounds of mass drug administration (MDA) with diethylcarbamazine and albendazole in the context of an LF elimination program in Leogane, Haiti. At baseline, overall Ascaris, Trichuris, and hookworm infection prevalences were 20.9%, 34.0%, and 11.2%, respectively (n = 2,716 stools). Nine months after the second MDA, Ascaris, Trichuris and hookworm prevalences had decreased significantly, to 14.1%, 14.6%, and 2.0%, respectively (n = 814 stools). Infection intensity decreased significantly for all three parasites as well. These results demonstrate that substantial reductions in intestinal helminth infections are associated with mass treatment of filariasis in Haiti and are consistent with the conclusion that high levels of coverage for the LF program can decrease transmission of geohelminths.

Generation and selection of naïve Fab library for parasitic antigen: Anti-BmSXP antibodies for lymphatic filariasis.

PubMed

Omar, Noorsharmimi; Hamidon, Nurul Hamizah; Yunus, Muhammad Hafiznur; Noordin, Rahmah; Choong, Yee Siew; Lim, Theam Soon

2018-05-01

Phage display has been applied successfully as a tool for the generation of monoclonal antibodies (mAbs). Naive antibody libraries are unique as they are able to overcome several limitations associated with conventional mAb generation methods like the hybridoma technology. Here, we performed an in vitro selection and generation of Fab antibodies against Brugia malayi SXP protein (BmSXP), a recombinant antigen for the detection of lymphatic filariasis. We developed a naïve multi ethnic Fab antibody library with an estimated diversity of 2.99 × 10 9 . The antibody library was used to screen for mAbs against BmSXP recombinant antigen. Soluble monoclonal Fab antibodies against BmSXP were successfully isolated from the naïve library. The Fab antibodies obtained were expressed and analyzed to show its binding capability. The diversity obtained from a pool of donors from various ethnic groups allowed for a diverse antibody library to be generated. The mAbs obtained were also functional in soluble form, which makes it useful for further downstream applications. We believe that the Fab mAbs are valuable for further studies and could also contribute to improvements in the diagnosis of filariasis. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

Mapping and modelling the impact of mass drug adminstration on filariasis prevalence in Myanmar.

PubMed

Aye, Ni Ni; Lin, Zaw; Lon, Khin Nan; Linn, Nay Yi Yi; Nwe, Thet Wai; Mon, Khin Mon; Ramaiah, Kapa; Betts, Hannah; Kelly-Hope, Louise A

2018-05-31

Lymphatic filariasis (LF) is endemic in Myanmar and targeted for elimination. To highlight the National Programme to Eliminate Lymphatic Filariasis (NPELF) progress between 2000 and 2014, this paper describes the geographical distribution of LF, the scale-up and impact of mass drug administration (MDA) implementation, and the first evidence of the decline in transmission in five districts. The LF distribution was determined by mapping historical and baseline prevalence data collected by NPELF. Data on the MDA implementation, reported coverage rates and sentinel site surveillance were summarized. A statistical model was developed from the available prevalence data to predict prevalence at township level by year of measurement. Transmission assessment survey (TAS) methods, measuring antigenemia (Ag) prevalence in children, were used to determine whether prevalence was below a level where recrudescence is unlikely to occur. The highest baseline LF prevalence was found in the Central Valley region. The MDA implementation activities scaled up to cover 45 districts, representing the majority of the endemic population, with drug coverage rates ranging from 60.0% to 98.5%. Challenges related to drug supply and local conflict were reported, and interrupted MDA in some districts. Overall, significant reductions in LF prevalence were found, especially after the first 2 to 3 rounds of MDA, which was supported by the corresponding model. The TAS activities in five districts found only two Ag positive children, resulting in all districts passing the critical threshold. Overall, the Myanmar NPELF has made positive steps forward in the elimination of LF despite several challenges, however, it needs to maintain momentum, drawing on international stakeholder support, to aim towards the national and global goals of elimination.

Coverage of, and compliance with, mass drug administration under the programme to eliminate lymphatic filariasis in India: a systematic review.

PubMed

Babu, Bontha V; Babu, Gopalan R

2014-09-01

India's mass drug administration (MDA) programme to eliminate lymphatic filariasis (PELF) covers all 250 endemic districts, but compliance with treatment is not adequate for the programme to succeed in eradicating this neglected tropical disease. The objective of our study was to systematically review published studies on the coverage of and compliance with MDA under the PELF in India. We searched several databases-PubMed/Medline, Google Scholar, CINAHL/EBSCO, Web of Knowledge (including Web of Science) and OVID-and by applying selection criteria identified a total of 36 papers to include in the review. Overall MDA coverage rates varied between 48.8% and 98.8%, while compliance rates ranged from 20.8% to 93.7%. The coverage-compliance gap is large in many MDA programmes. The effective level of compliance, ≥65%, was reported in only 10 of a total of 31 MDAs (5 of 20 MDAs in rural areas and 2 of 12 MDAs in urban areas). The review has identified a gap between coverage and compliance, and potentially correctable causes of this gap. These causes need to be addressed if the Indian programme is to advance towards elimination of lymphatic filariasis. © 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.

[Prevalence of Bancroftian filariasis in seven villages of the Bonassama Health District in the Wouri Estuary, littoral province of Cameroon].

PubMed

Moyou-Somo, R; Ouambe, M Antoine; Fon, E; Bema, J

2003-01-01

Lymphatic filariasis is one of the 6 diseases targeted for global eradication by the World Health Organization. In 2000 Cameroon was selected for inclusion in the eradication program. As a prerequisite for the program, epidemiological mapping was undertaken to determine the prevalence of Wuchereria bancrofti in 7 villages located in the mangrove area of the Wouri estuary littoral province of Cameroon. Informed consent was obtained from each participant or from parents of minors. Night blood specimens were collected for thick and thin blood films, stained using the Giemsa solution, and microscopically examined to identify microfilariae of W. bancrofti. The study population included 924 subjects (336 males and 558 females). Their age ranged from 1 to 79 years (mean, 26.9 years). W. bancrofti was identified in 4 of the 7 villages with prevalence rates ranging from 0.7% to 3.25% (mean, 0.97%). All positive subjects were over 30 years old. Despite night blood specimen collection, other blood microfilariae were detected including Loa loa in 54 cases (prevalence, 5.84%) and Dipetalonema perstans in 10 (prevalence, 1.1%). Only a small number of subjects presented clinical manifestations of lymphatic filariasis (e.g., pruritus). Elephantiasis of the lower limb was identified in only one subject but there was hearsay evidence of other cases involving subjects embarrassed to come forward.

Toxicity of some plant extracts against vector of lymphatic filariasis, Culex pipiens.

PubMed

Hasaballah, Ahmed I

2015-04-01

Many insecticides are generally used as larvicides to control Culex pipiens, vector of lymphatic filariasis. This study was undertaken to evaluate the larvicidal activity of some potential larvicidal plants extracts against C. pipiens larvae. The toxic effects of both ethanolic and petroleum ether plant extracts were evaluated under laboratory conditions against 3rd instar larvae of C. pipiens. Forty ethanolic and petroleum ether extracts of 10 plants namely Echinochloa stagninum, Phragmites australis, Eichhornia crassipes, Rhizophora mucronata, Cichorium intybus, Ocimum basilicum, Origanum majorana, Azadirachta indica, Rosmarinus officinalis and Nigella sativa. On the basis of LC50, the toxic effect of the plant extracts tested varied depending on the plant species, part, solvent used in extraction and the extract concentrations. The petroleum ether extraction was more effective against mosquito as compared with ethanolic extraction. The most effective plant extract was A. indica followed by Ph. australis, N. sativa, C. intybus, R. officinalis, O. basilicum, O. majorana, E. stagninum, Rh. Mucronata and E. crassipes.

Essential proteins and possible therapeutic targets of Wolbachia endosymbiont and development of FiloBase-a comprehensive drug target database for Lymphatic filariasis

NASA Astrophysics Data System (ADS)

Sharma, Om Prakash; Kumar, Muthuvel Suresh

2016-01-01

Lymphatic filariasis (Lf) is one of the oldest and most debilitating tropical diseases. Millions of people are suffering from this prevalent disease. It is estimated to infect over 120 million people in at least 80 nations of the world through the tropical and subtropical regions. More than one billion people are in danger of getting affected with this life-threatening disease. Several studies were suggested its emerging limitations and resistance towards the available drugs and therapeutic targets for Lf. Therefore, better medicine and drug targets are in demand. We took an initiative to identify the essential proteins of Wolbachia endosymbiont of Brugia malayi, which are indispensable for their survival and non-homologous to human host proteins. In this current study, we have used proteome subtractive approach to screen the possible therapeutic targets for wBm. In addition, numerous literatures were mined in the hunt for potential drug targets, drugs, epitopes, crystal structures, and expressed sequence tag (EST) sequences for filarial causing nematodes. Data obtained from our study were presented in a user friendly database named FiloBase. We hope that information stored in this database may be used for further research and drug development process against filariasis. URL: http://filobase.bicpu.edu.in.

Rapid Assessment Procedure for Loiasis and Mapping Lymphatic Filariasis: Two Perfect Illustrations of “To Be in English or Not to Be”

PubMed Central

Carme, Bernard

2012-01-01

Interest in filariasis has found a new impetus now that neglected tropical diseases have their own journal. However, some of the advances published in renowned international journals have completely ignored previous publications on the subject, particularly those in languages other than English. The rapid assessment procedure for loiasis and the mapping of lymphatic filariasis provide two perfect illustrations of this. This problem may seem a bit outdated, given that all “good authors” now publish exclusively in English. It certainly is outdated for most areas of medicine. But, surely, this should not be the case for neglected tropical diseases, for which certain long-standing findings are every bit as important as what may be presented as new discoveries. One possibility would be for certain journals, such as PLOS Neglected Tropical Diseases, to include a specific heading permitting the publication in English of older studies that initially appeared in a language other than English. The texts would be English versions respecting the entirety of the original text. Submission should be accompanied by a presentation of the problem, with details and explanatory comments, with submission at the initiative of the authors of the former article in question or their students or sympathizers. PMID:23272254

Human toxocariasis: frequency of anti-Toxocara antibodies in children and adolescents from an outpatient clinic for lymphatic filariasis in Recife, Northeast Brazil.

PubMed

Aguiar-Santos, Ana Maria; Andrade, Luiz D; Medeiros, Zulma; Chieffi, Pedro Paulo; Lescano, Suzana Z; Perez, Emília P

2004-01-01

In a transversal study on a sample of 386 children and adolescents from an outpatient clinic for filariasis in Recife, Northeast Brazil, the frequency of anti-Toxocara antibodies and its relation to age, gender, number of peripheral eosinophils, Wuchereria bancrofti microfilariae and intestinal helminths was determined. The total anti-Toxocara IgG antibody frequency was 39.4%, by ELISA technique. The difference in frequency between males (40.1%) and females (37.6%) was not statistically significant. The 6 to 10-year-old subset presented the highest frequency of anti-Toxocara antibodies (60%), and within this age group there was a statistically significant male bias. There was also a significant association between the number of eosinophils and the presence of anti-Toxocara antibodies. Intestinal parasite frequency was 52.1%, but no association was found between this data and the presence of anti-Toxocara antibodies. In the present sample, 42.2% of the patients were Wuchereria bancrofti carriers, however, again this was not associated with the presence of anti-Toxocara antibodies. In conclusion, anti-Toxocara antibodies were highly prevalent in this sample. The present data show that there is no cross correlation between anti-Toxocara IgG antibody and the presence of intestinal helminths and filariasis.

Long-Lasting Insecticidal Nets Are Synergistic with Mass Drug Administration for Interruption of Lymphatic Filariasis Transmission in Nigeria

PubMed Central

Eigege, Abel; Miri, Emmanuel; Sallau, Adamu; Umaru, John; Mafuyai, Hayward; Chuwang, Yohanna S.; Danjuma, Goshit; Danboyi, Jacob; Adelamo, Solomon E.; Mancha, Bulus S.; Okoeguale, Bridget; Patterson, Amy E.; Rakers, Lindsay; Richards, Frank O.

2013-01-01

In central Nigeria Anopheles mosquitoes transmit malaria and lymphatic filariasis (LF). The strategy used for interrupting LF transmission in this area is annual mass drug administration (MDA) with albendazole and ivermectin, but after 8 years of MDA, entomological evaluations in sentinel villages showed continued low-grade mosquito infection rates of 0.32%. After long-lasting insecticidal net (LLIN) distribution by the national malaria program in late 2010, however, we were no longer able to detect infected vectors over a 24-month period. This is evidence that LLINs are synergistic with MDA in interrupting LF transmission. PMID:24205421

The 6th Meeting of the Global Alliance to Eliminate Lymphatic Filariasis: A half-time review of lymphatic filariasis elimination and its integration with the control of other neglected tropical diseases

PubMed Central

2010-01-01

The 6th Meeting of the Global Alliance to Eliminate Lymphatic Filariasis (GAELF6) was held 1-3 June, 2010 in Seoul, Korea, with 150 participants from 38 countries. The year 2010 marks the midpoint between the first GAELF meeting, in 2000, and the World Health Organization (WHO) 2020 goal of global elimination of lymphatic filariasis (LF) as a public health problem. The theme of the meeting, "Half-time in LF Elimination: Teaming Up with Neglected Tropical Diseases (NTDs)," reflected significant integration of LF elimination programmes into a comprehensive initiative to control NTDs. Presentations on LF epidemiology, treatment, research, and programmes highlighted both accomplishments and remaining challenges. The WHO strategy to interrupt LF transmission is based on annual mass drug administration (MDA) using two-drug combinations. After mapping the geographic distribution of LF, MDA is implemented for ≥ 5 years, followed by a period of post-MDA surveillance, and, ultimately, verification of LF elimination. Morbidity management further reduces disease burden. Of 81 countries considered LF-endemic in 2000, 52 (64.2%) have begun MDA; 10 (12.3%) others with low-level transmission are unlikely to require MDA. In 2008, ~695 million people were offered treatment (51.7% of the at-risk population); ~496 million participated. Approximately 22 million people have been protected from LF infection and disease, with savings of ~US $24.2 billion. Morbidity management programmes have been implemented in 27 (33.3%) countries. Significant challenges to LF elimination remain. These include: initiating MDA in the remaining 19 countries that require it; achieving full geographic coverage in countries where MDA has started; finding alternative strategies to address the problem of Loa loa co-endemicity in Central Africa; developing strategies to treat urban populations; initiating and sustaining MDA in settings of armed conflict; developing refined guidelines and procedures for

The effects of size and synthesis methods of gold nanoparticle-conjugated MαHIgG4 for use in an immunochromatographic strip test to detect brugian filariasis

NASA Astrophysics Data System (ADS)

Rabizah Makhsin, Siti; Razak, Khairunisak Abdul; Noordin, Rahmah; Dyana Zakaria, Nor; Chun, Tan Soo

2012-12-01

This study describes the properties of colloidal gold nanoparticles (AuNPs) with sizes of 20, 30 and 40 nm, which were synthesized using citrate reduction or seeding-growth methods. Likewise, the conjugation of these AuNPs to mouse anti-human IgG4 (MαHIgG4) was evaluated for an immunochromatographic (ICG) strip test to detect brugian filariasis. The morphology of the AuNPs was studied based on the degree of ellipticity (G) of the transmission electron microscopy images. The AuNPs produced using the seeding-growth method showed lower ellipticity (G ≤ 1.11) as compared with the AuNPs synthesized using the citrate reduction method (G ≤ 1.18). Zetasizer analysis showed that the AuNPs that were synthesized using the seeding-growth method were almost monodispersed with a lower polydispersity index (PDI; PDI≤0.079), as compared with the AuNPs synthesized using the citrate reduction method (PDI≤0.177). UV-visible spectroscopic analysis showed a red-shift of the absorbance spectra after the reaction with MαHIgG4, which indicated that the AuNPs were successfully conjugated. The optimum concentration of the BmR1 recombinant antigen that was immobilized on the surface of the ICG strip on the test line was 1.0 mg ml-1. When used with the ICG test strip assay and brugian filariasis serum samples, the conjugated AuNPs-MαHIgG4 synthesized using the seeding-growth method had faster detection times, as compared with the AuNPs synthesized using the citrate reduction method. The 30 nm AuNPs-MαHIgG4, with an optical density of 4 from the seeding-growth method, demonstrated the best performance for labelling ICG strips because it displayed the best sensitivity and the highest specificity when tested with serum samples from brugian filariasis patients and controls.

The effects of size and synthesis methods of gold nanoparticle-conjugated MαHIgG4 for use in an immunochromatographic strip test to detect brugian filariasis.

PubMed

Makhsin, Siti Rabizah; Razak, Khairunisak Abdul; Noordin, Rahmah; Zakaria, Nor Dyana; Chun, Tan Soo

2012-12-14

This study describes the properties of colloidal gold nanoparticles (AuNPs) with sizes of 20, 30 and 40 nm, which were synthesized using citrate reduction or seeding-growth methods. Likewise, the conjugation of these AuNPs to mouse anti-human IgG(4) (MαHIgG(4)) was evaluated for an immunochromatographic (ICG) strip test to detect brugian filariasis. The morphology of the AuNPs was studied based on the degree of ellipticity (G) of the transmission electron microscopy images. The AuNPs produced using the seeding-growth method showed lower ellipticity (G ≤ 1.11) as compared with the AuNPs synthesized using the citrate reduction method (G ≤ 1.18). Zetasizer analysis showed that the AuNPs that were synthesized using the seeding-growth method were almost monodispersed with a lower polydispersity index (PDI; PDI≤0.079), as compared with the AuNPs synthesized using the citrate reduction method (PDI≤0.177). UV-visible spectroscopic analysis showed a red-shift of the absorbance spectra after the reaction with MαHIgG(4), which indicated that the AuNPs were successfully conjugated. The optimum concentration of the BmR1 recombinant antigen that was immobilized on the surface of the ICG strip on the test line was 1.0 mg ml(-1). When used with the ICG test strip assay and brugian filariasis serum samples, the conjugated AuNPs-MαHIgG(4) synthesized using the seeding-growth method had faster detection times, as compared with the AuNPs synthesized using the citrate reduction method. The 30 nm AuNPs-MαHIgG(4), with an optical density of 4 from the seeding-growth method, demonstrated the best performance for labelling ICG strips because it displayed the best sensitivity and the highest specificity when tested with serum samples from brugian filariasis patients and controls.

Investing in Justice: Ethics, Evidence, and the Eradication Investment Cases for Lymphatic Filariasis and Onchocerciasis

PubMed Central

Merritt, Maria W.; Tediosi, Fabrizio

2015-01-01

It has been suggested that initiatives to eradicate specific communicable diseases need to be informed by eradication investment cases to assess the feasibility, costs, and consequences of eradication compared with elimination or control. A methodological challenge of eradication investment cases is how to account for the ethical importance of the benefits, burdens, and distributions thereof that are salient in people’s experiences of the diseases and related interventions but are not assessed in traditional approaches to health and economic evaluation. We have offered a method of ethical analysis grounded in theories of social justice. We have described the method and its philosophical rationale and illustrated its use in application to eradication investment cases for lymphatic filariasis and onchocerciasis, 2 neglected tropical diseases that are candidates for eradication. PMID:25713967

Partnering for impact: Integrated transmission assessment surveys for lymphatic filariasis, soil transmitted helminths and malaria in Haiti.

PubMed

Knipes, Alaine Kathryn; Lemoine, Jean Frantz; Monestime, Franck; Fayette, Carl R; Direny, Abdel N; Desir, Luccene; Beau de Rochars, Valery E; Streit, Thomas G; Renneker, Kristen; Chu, Brian K; Chang, Michelle A; Mace, Kimberly E; Won, Kimberly Y; Lammie, Patrick J

2017-02-01

Since 2001, Haiti's National Program for the Elimination of Lymphatic Filariasis (NPELF) has worked to reduce the transmission of lymphatic filariasis (LF) through annual mass drug administration (MDA) with diethylcarbamazine and albendazole. The NPELF reached full national coverage with MDA for LF in 2012, and by 2014, a total of 14 evaluation units (48 communes) had met WHO eligibility criteria to conduct LF transmission assessment surveys (TAS) to determine whether prevalence had been reduced to below a threshold, such that transmission is assumed to be no longer sustainable. Haiti is also endemic for malaria and many communities suffer a high burden of soil transmitted helminths (STH). Heeding the call from WHO for integration of neglected tropical diseases (NTD) activities, Haiti's NPELF worked with the national malaria control program (NMCP) and with partners to develop an integrated TAS (LF-STH-malaria) to include assessments for malaria and STH. The aim of this study was to evaluate the feasibility of using TAS surveys for LF as a platform to collect information about STH and malaria. Between November 2014 and June 2015, TAS were conducted in 14 evaluation units (EUs) including 1 TAS (LF-only), 1 TAS-STH-malaria, and 12 TAS-malaria, with a total of 16,655 children tested for LF, 14,795 tested for malaria, and 298 tested for STH. In all, 12 of the 14 EUs passed the LF TAS, allowing the program to stop MDA for LF in 44 communes. The EU where children were also tested for STH will require annual school-based treatment with albendazole to maintain reduced STH levels. Finally, only 12 of 14,795 children tested positive for malaria by RDT in 38 communes. Haiti's 2014-2015 Integrated TAS surveys provide evidence of the feasibility of using the LF TAS as a platform for integration of assessments for STH and or malaria.

The NIH-NIAID Filariasis Research Reagent Resource Center

PubMed Central

Michalski, Michelle L.; Griffiths, Kathryn G.; Williams, Steven A.; Kaplan, Ray M.; Moorhead, Andrew R.

2011-01-01

Filarial worms cause a variety of tropical diseases in humans; however, they are difficult to study because they have complex life cycles that require arthropod intermediate hosts and mammalian definitive hosts. Research efforts in industrialized countries are further complicated by the fact that some filarial nematodes that cause disease in humans are restricted in host specificity to humans alone. This potentially makes the commitment to research difficult, expensive, and restrictive. Over 40 years ago, the United States National Institutes of Health–National Institute of Allergy and Infectious Diseases (NIH-NIAID) established a resource from which investigators could obtain various filarial parasite species and life cycle stages without having to expend the effort and funds necessary to maintain the entire life cycles in their own laboratories. This centralized resource (The Filariasis Research Reagent Resource Center, or FR3) translated into cost savings to both NIH-NIAID and to principal investigators by freeing up personnel costs on grants and allowing investigators to divert more funds to targeted research goals. Many investigators, especially those new to the field of tropical medicine, are unaware of the scope of materials and support provided by the FR3. This review is intended to provide a short history of the contract, brief descriptions of the fiilarial species and molecular resources provided, and an estimate of the impact the resource has had on the research community, and describes some new additions and potential benefits the resource center might have for the ever-changing research interests of investigators. PMID:22140585

Minocycline as a re-purposed anti-Wolbachia macrofilaricide: superiority compared with doxycycline regimens in a murine infection model of human lymphatic filariasis

PubMed Central

Sharma, Raman; Jayoussi, Ghaith Al; Tyrer, Hayley E.; Gamble, Joanne; Hayward, Laura; Guimaraes, Ana F.; Davies, Jill; Waterhouse, David; Cook, Darren A. N.; Myhill, Laura J.; Clare, Rachel H.; Cassidy, Andrew; Steven, Andrew; Johnston, Kelly L.; Ford, Louise; Turner, Joseph D.; Ward, Stephen A.; Taylor, Mark J.

2016-01-01

Lymphatic filariasis and onchocerciasis are parasitic helminth diseases, which cause severe morbidities such as elephantiasis, skin disease and blindness, presenting a major public health burden in endemic communities. The anti-Wolbachia consortium (A·WOL: http://www.a-wol.com/) has identified a number of registered antibiotics that target the endosymbiotic bacterium, Wolbachia, delivering macrofilaricidal activity. Here we use pharmacokinetics/pharmacodynamics (PK/PD) analysis to rationally develop an anti-Wolbachia chemotherapy by linking drug exposure to pharmacological effect. We compare the pharmacokinetics and anti-Wolbachia efficacy in a murine Brugia malayi model of minocycline versus doxycycline. Doxycycline exhibits superior PK in comparison to minocycline resulting in a 3-fold greater exposure in SCID mice. Monte-Carlo simulations confirmed that a bi-daily 25–40 mg/Kg regimen is bioequivalent to a clinically effective 100–200 mg/day dose for these tetracyclines. Pharmacodynamic studies showed that minocycline depletes Wolbachia more effectively than doxycycline (99.51% vs. 90.35%) after 28 day 25 mg/Kg bid regimens with a more potent block in microfilarial production. PK/PD analysis predicts that minocycline would be expected to be 1.7 fold more effective than doxycycline in man despite lower exposure in our infection models. Our findings warrant onward clinical investigations to examine the clinical efficacy of minocycline treatment regimens against lymphatic filariasis and onchocerciasis. PMID:26996237

Larval susceptibility of Aloe barbadensis and Cannabis sativa against Culex quinquefasciatus, the filariasis vector.

PubMed

Maurya, Prejwltta; Mohan, Lalit; Sharma, Preeti; Srivastava, C N

2008-11-01

Larvicidal potential of petroleum ether, carbon tetrachloride and methanol extracts of Aloe barbadensis and Cannabis sativa has been investigated against Culex quinquefasciatus. Among the extracts examined, Carbon tetrachloride extract (Cte) of Aloe barbadensis was the most effective with LC50 values of 15.31 and 11.01 ppm after 24 and 48 hr of exposure, respectively followed by pertoleum ether extract (Pee) of A barbadensis, Cte of C. sativa, methanol extract (Mee) of A. barbadensis, methanol and petroleum ether of C. saliva, LC, being 25.97, 88.51, 144.44, 160.78 and 294.42 ppm affer 24hr and 16.60, 68.69, 108.38, 71.71 and 73.32 ppm after 48 hr of post treatment, respectively. Cte of both the plants exhibits potential larvicidal activity and can be used as ecofriendly alternative in the management of the filariasis vector, Culex quinquefasciatus.

The Global Programme to Eliminate Lymphatic Filariasis: History and achievements with special reference to annual single-dose treatment with diethylcarbamazine in Samoa and Fiji.

PubMed

Kimura, Eisaku

2011-03-01

Diethylcarbamazine (DEC), first introduced in 1947, was shown to have strong efficacy and safety for treatment of human lymphatic filariasis, which is caused mostly by a species Wuchereria bancrofti. Many studies to optimize the dosage and treatment schedule of DEC followed, and, based on the results, control programs with various regimens were implemented in different endemic areas/countries. By the mid 1970s, with endorsement by the WHO Expert Committee on Filariasis (3rd report, 1974), the standard DEC regimen for W. bancrofti infection in mass treatment had been established in principle: a total dose of 72 mg/kg of body weight given in 12 divided doses, once weekly or monthly, at 6 mg/kg each. Not long after the committee report, the efficacy of annual single-dose treatment at 6 mg/kg, which is only one twelfth of the WHO-recommended dose in a year, was reported effective in French Polynesia (study period: 1973-78), and later in Samoa (study period: 1979-81). These results were published between 1978 and 1985 in the Bulletin of WHO but received little attention. In the mid 1980s, the efficacy of ivermectin, the first-choice drug for onchocerciasis, against lymphatic filariae came to light. Since the effect at a single dose was remarkable, and often better than DEC, it was predicted that the newly introduced drug would replace DEC. Treatment experiments with ivermectin increased quickly in number. Meanwhile, annual single-dose mass drug administration (MDA) with DEC at 6 mg/kg was under scrutiny in Samoa and Fiji. In the early 1990s, the Samoan study, which covered the entire population of 160,000 with 3 annual MDAs, reported a significant reduction in microfilaria (mf) prevalence and mean mf density, while in Fiji, the efficacy of 5 rounds of annual MDA (total dose, 30 mg/kg) was shown to be as effective as 28 multi-dose MDA spread over 2 years (6 weekly plus 22 monthly treatments at 5 mg/kg; total dose, 140 mg/kg). Several additional studies carried out in

Modelling strategies to break transmission of lymphatic filariasis--aggregation, adherence and vector competence greatly alter elimination.

PubMed

Irvine, M A; Reimer, L J; Njenga, S M; Gunawardena, S; Kelly-Hope, L; Bockarie, M; Hollingsworth, T D

2015-10-22

With ambitious targets to eliminate lymphatic filariasis over the coming years, there is a need to identify optimal strategies to achieve them in areas with different baseline prevalence and stages of control. Modelling can assist in identifying what data should be collected and what strategies are best for which scenarios. We develop a new individual-based, stochastic mathematical model of the transmission of lymphatic filariasis. We validate the model by fitting to a first time point and predicting future timepoints from surveillance data in Kenya and Sri Lanka, which have different vectors and different stages of the control programme. We then simulate different treatment scenarios in low, medium and high transmission settings, comparing once yearly mass drug administration (MDA) with more frequent MDA and higher coverage. We investigate the potential impact that vector control, systematic non-compliance and different levels of aggregation have on the dynamics of transmission and control. In all settings, increasing coverage from 65 to 80 % has a similar impact on control to treating twice a year at 65 % coverage, for fewer drug treatments being distributed. Vector control has a large impact, even at moderate levels. The extent of aggregation of parasite loads amongst a small portion of the population, which has been estimated to be highly variable in different settings, can undermine the success of a programme, particularly if high risk sub-communities are not accessing interventions. Even moderate levels of vector control have a large impact both on the reduction in prevalence and the maintenance of gains made during MDA, even when parasite loads are highly aggregated, and use of vector control is at moderate levels. For the same prevalence, differences in aggregation and adherence can result in very different dynamics. The novel analysis of a small amount of surveillance data and resulting simulations highlight the need for more individual level data to be

Surgical management of morbidity due to lymphatic filariasis: the usefulness of a standardized international clinical classification of hydroceles.

PubMed

Capuano, G P; Capuano, C

2012-03-01

The objective of this work is to evaluate the usefulness of a standardized clinical classification of hydroceles in lymphatic filariasis endemic countries to guide their surgical management. 64 patients with hydroceles were operated in 2009-2010, in Level II hospitals (WHO classification), during two visits to Fiji, by the same mobile surgical team. The number of hydroceles treated was 83. We developed and evaluated a much needed clinical classification of hydroceles based on four criteria: Type (uni/bilateral); Side (left/right); Stage of enlargement of the scrotum rated from I to VI; Grade of burial of the penis rated from 0 to 4. It lead to the conclusion that 1) A Stage I or II hydrocele, associated with Grade 0 or 1 penis burial could be considered a "Simple Hydrocele". The surgical treatment is simple with no anticipated early complication. WHO Level II of health care structure seems adapted. 2) A Stage III or IV hydrocele associated with Grade 2, 3 or 4 penis burial could be considered a "Complicated Hydrocele". The operation is longer, more complicated and the possibility of occurrence of complications seems greater. A level III health care facility would be more adapted under the normal functioning of the health system. We conclude that a standardized clinical classification of hydroceles based on the Stage of enlargement of the scrotum and the Grade of burial of the penis appears to be a useful tool to guide the decision about the level of care and the surgical technique required. We use the same classification for penoscrotal lymphoedema. A decision tree is presented for the management of hydroceles in lymphatic filariasis endemic countries which could usefully complement the "Algorithm for management of scrotal swelling" proposed by WHO in 2002. An international classification system of hydroceles would also allow standardization and facilitate study design and comparisons of their results.

An application of remotely derived climatological fields for risk assessment of vector-borne diseases : a spatial study of filariasis prevalence in the Nile Delta, Egypt.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crombie, M. K.; Gillies, R. R.; Arvidson, R. E.

1999-12-01

This paper applies a relatively straightforward remote sensing method that is commonly used to derive climatological variables. Measurements of surface reflectance and surface radiant temperature derived from Landsat Thematic Mapper data were used to create maps of fractional vegetation and surface soil moisture availability for the southern Nile delta in Egypt. These climatological variables were subsequently used to investigate the spatial distribution of the vector borne disease Bancroftian filariasis in the Nile delta where it is focally endemic and a growing problem. Averaged surface soil moisture values, computed for a 5-km border area around affected villages, were compared to filariasismore » prevalence rates. Prevalence rates were found to be negligible below a critical soil moisture value of 0.2, presumably because of a lack of appropriate breeding sites for the Culex Pipiens mosquito species. With appropriate modifications to account for local conditions and vector species, this approach should be useful as a means to map, predict, and control insect vector-borne diseases that critically depend on wet areas for propagation. This type of analysis may help governments and health agencies that are involved in filariasis control to better focus limited resources to identifiable high-risk areas.« less

Multicentre evaluations of two new rapid IgG4 tests (WB rapid and panLF rapid) for detection of lymphatic filariasis

PubMed Central

Noordin, Rahmah; Itoh, Makoto; Kimura, Eisaku; Abdul Rahman, Rohana; Ravindran, Balachandran; Mahmud, Rohela; Supali, Taniawati; Weerasooriya, Mirani

2007-01-01

In the global effort to eliminate lymphatic filariasis (LF), rapid field-applicable tests are useful tools that will allow on-site testing to be performed in remote places and the results to be obtained rapidly. Exclusive reliance on the few existing tests may jeopardize the progress of the LF elimination program, thus the introduction of other rapid tests would be useful to address this issue. Two new rapid immunochromatographic IgG4 cassette tests have been produced, namely WB rapid and panLF rapid, for detection of bancroftian filariasis and all three species of lymphatic filaria respectively. WB rapid was developed using BmSXP recombinant antigen, while PanLF rapid was developed using BmR1 and BmSXP recombinant antigens. A total of 165 WB rapid and 276 panLF rapid tests respectively were evaluated at USM and the rest were couriered to another university in Malaysia (98 WB rapid, 129 panLF rapid) and to universities in Indonesia (56 WB rapid, 62 panLF rapid), Japan (152 of each test) and India (18 of each test) where each of the tests underwent independent evaluations in a blinded manner. The average sensitivities of WB rapid and panLF rapid were found to be 97.6% (94%–100%) and 96.5% (94%–100%) respectively; while their average specificities were both 99.6% (99%–100%). Thus this study demonstrated that both the IgG4 rapid tests were highly sensitive and specific, and would be useful additional tests to facilitate the global drive to eliminate this disease. PMID:17961262

Precontrol observations on lymphatic filariasis & geo-helminthiases in two coastal districts of rural Orrisa.

PubMed

Chhotray, G P; Ranjit, M R; Khuntia, H K; Acharya, A S

2005-11-01

Lymphatic filariasis (LF) is a major public health problem in India, accounting for 40 per cent of the global burden. The World Health Organization has launched a global programme to eliminate LF by 2020 and India is a signatory to it. Orissa, an eastern Indian State has long been known to be endemic for LF. Prior to implementation of mass drug administration programme it is important to collect baseline data on filariasis and geo-helminthiases in the State. The present cross-sectional survey was therefore carried out between February and December 2001 to obtain baseline information on both LF and geo-helminthiases before application of the control measures. The study was carried out in rural areas of Puri and Ganjam districts in two phases. In phase I, the distribution of microfilaraemia in two district was mapped out in randomly selected primary health centres (PHCs), and 12 microfilaraemic villages were identified in each district by cluster analysis for the phase II study. In phase II, detailed clinical and parasitological survey for LF and geo-helminthiases was carried out following the standard procedures. Wuchereria bancrofti was found to be widely prevalent in Puri district with certain pockets of Brugia malayi while W. bancrofti was the only species in Ganjam district. The microfilaraemia (Mf) rate was found to be 9.5 and 11.1 per cent; and circulating filarial antigenaemia (CFA) was 16.8 and 17.8 per cent in Puri and Ganjam respectively. The geometric mean intensity (GMI) of Mf per ml of blood among positive individuals was 387 in Puri and 454 in Ganjam. The overall disease rate in Puri was 7.9 and 8.9 per cent in Ganjam. The prevalence of chronic manifestations was found to be significantly higher (P<0.001) than the acute manifestations in both the districts. The prevalence of geo-helminthiases was 31.8 per cent in Puri and 42.1 per cent in Ganjam; and the heavy infection was found to be significantly higher (P<0.001) in Ganjam compared to Puri district

Biology and control of Taeniorhynchus (Mansonioides) uniformis Theobald, the chief vector of rural filariasis in Ceylon

PubMed Central

Antonipulle, P.; David, H. V.; Karunaratne, M. D. R.

1958-01-01

Residual spraying of DDT for the control of Taeniorhynchus (Mansonioides) uniformis, the mosquito vector of rural filariasis in Ceylon, was carried out in Induruwa, a village on the west coast of the island. The results showed that the insecticide retained its effectiveness for a period of 4-6 months. During the course of this investigation, various observations were made on the behaviour of T. (M.) uniformis. Its host plants, day-time resting-places, feeding habits, and response to light—particularly moonlight—were recorded. An increase in T. (M.) uniformis prevalence was observed to coincide with the onset of the north-east and south-west monsoons, when the paddy-fields are inundated and become overgrown with Isachne australis, the most common aquatic plant in the area and a favourite breeding-place of this mosquito species. PMID:13585075

A systematic review of factors that shape implementation of mass drug administration for lymphatic filariasis in sub-Saharan Africa.

PubMed

Silumbwe, Adam; Zulu, Joseph Mumba; Halwindi, Hikabasa; Jacobs, Choolwe; Zgambo, Jessy; Dambe, Rosalia; Chola, Mumbi; Chongwe, Gershom; Michelo, Charles

2017-05-22

Understanding factors surrounding the implementation process of mass drug administration for lymphatic filariasis (MDA for LF) elimination programmes is critical for successful implementation of similar interventions. The sub-Saharan Africa (SSA) region records the second highest prevalence of the disease and subsequently several countries have initiated and implemented MDA for LF. Systematic reviews have largely focused on factors that affect coverage and compliance, with less attention on the implementation of MDA for LF activities. This review therefore seeks to document facilitators and barriers to implementation of MDA for LF in sub-Saharan Africa. A systematic search of databases PubMed, Science Direct and Google Scholar was conducted. English peer-reviewed publications focusing on implementation of MDA for LF from 2000 to 2016 were considered for analysis. Using thematic analysis, we synthesized the final 18 articles to identify key facilitators and barriers to MDA for LF programme implementation. The main factors facilitating implementation of MDA for LF programmes were awareness creation through innovative community health education programmes, creation of partnerships and collaborations, integration with existing programmes, creation of morbidity management programmes, motivation of community drug distributors (CDDs) through incentives and training, and management of adverse effects. Barriers to implementation included the lack of geographical demarcations and unregistered migrations into rapidly urbanizing areas, major disease outbreaks like the Ebola virus disease in West Africa, delayed drug deliveries at both country and community levels, inappropriate drug delivery strategies, limited number of drug distributors and the large number of households allocated for drug distribution. Mass drug administration for lymphatic filariasis elimination programmes should design their implementation strategies differently based on specific contextual factors to

Screening Mosquito House Entry Points as a Potential Method for Integrated Control of Endophagic Filariasis, Arbovirus and Malaria Vectors

PubMed Central

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

The "filarial dance" is not characteristic of filariasis: observations of "dancing megasperm" on high-resolution sonography in patients from nonendemic areas mimicking the filarial dance and a proposed mechanism for this phenomenon.

PubMed

Adejolu, Margaret; Sidhu, Paul S

2011-08-01

The objective of this series was to show that the sonographic appearance described as the "filarial dance" is not characteristic of filariasis but occurs in nonendemic areas as a manifestation of epididymal obstruction. An experienced observer documented cases after initial observation of the filarial dance in routine clinical practice using high-frequency linear array transducers. The filarial dance was described as excessive to-and-fro movement of echogenic particles within a prominent epididymis and graded 1 to 4 according to the extent and distribution of the abnormality. The country of birth, exposure to filarial infection or travel to a filarial-endemic area, previous scrotal surgery including vasectomy, any previous or current scrotal inflammatory disease, and any congenital testicular abnormalities were recorded. Over a 10-year period, sonographic appearances consistent with the filarial dance were observed in 18 patients (bilateral in 6). The mean patient age was 47.7 (range, 28-91) years. The abnormality was graded in the 24 affected testes as follows: grade 1, n = 3; grade 2, n = 8; grade 3, n = 8; and grade 4, n = 5. No patient had a history of filariasis or travel to an endemic area. Six of 18 patients (33.3%) had bilateral vasectomies; 5 (27.8%) had a history of epididymo-orchitis in the ipsilateral testis; 3 (16.7%) had previous scrotal surgery; and 4 (22.2%) had no relevant urologic history. We have described a sonographic appearance identical to the filarial dance in men with no history of filarial infection. Most had previous scrotal surgery or infection, suggesting that the filarial dance may not always be due to movement of filarial worms. The unifying condition in patients with filariasis and our patients is lymphatic obstruction, likely the underlying cause of the appearance in both groups.

Knowledge on lymphatic filariasis and the response to July 2002 mass treatment campaign in two communities in the Galle district.

PubMed

Yahathugoda, T C; Wickramasinghe, D; Liyanage, Tilaks S; Weerasooriya, Mirani V; Mudalige, Malka P; Waidyaratna, Eisha I; Samarawickrema, W A

2003-09-01

To ascertain the knowledge on filariasis and response to the July 2002 mass treatment campaign in two sample populations. Application of pre-tested questionnaire by direct interviews of individuals from randomly selected streets. Study areas were a coastal community in Unawatuna (population sample 381), and an inland community in Baddegama (population sample 236) in the Galle district. They were interviewed twice, 4 weeks before the mass drug administration (MDA) and 4 to 7 days after. The sample population of Unawatuna had a greater awareness of the clinical and parasitological features of the disease (p = 0.0003) and the drug treatment (p = 0.00380 than that of Baddegama. Only 5.5% of the combined sample attributed the cause of filariasis to a parasitic worm. However, over 70.0% of them knew that transmission was through mosquito bites. Volunteers formed 87.5% of the work force used for drug distribution in Unawatuna and 70.1% in Baddegama. The balance work force were Grama Niladaris and Public Health Midwives. Drugs were received by 76.9% of the Unawatuna sample compared with 89.0% at Baddegama (p < 0.001). Among those who received the drugs, consumption was 91.8% in Unawatuna and 96.2% in Baddegama. Taking the two communities together adverse effects were experienced by 22.9%. These effects in night time drug consumers (10.4%) were significantly less than in day time consumers (19.8%) (p < 0.005). The adverse effects were sleepiness (37.8%), malaise (28.2%), headache (16.8%), vomiting (5.1%), nausea (4.5%) and fever (3.9%). The message of mass treatment was carried to the community by the people themselves on the eve and on the day of drug distribution. Over 95% agreed that in future programs drugs should be delivered to their homes.

The role of gender relations in uptake of mass drug administration for lymphatic filariasis in Alor District, Indonesia.

PubMed

Krentel, Alison; Wellings, Kaye

2018-03-12

The Global Programme to Eliminate Lymphatic Filariasis has set 2020 as a target to eliminate lymphatic filariasis (LF) as a public health problem through mass drug administration (MDA) to all eligible people living in endemic areas. To obtain a better understanding of compliance with LF treatment, a qualitative study using 43 in-depth interviews was carried out in Alor District, Indonesia to explore factors that motivate uptake of LF treatment, including the social and behavioural differences between compliant and non-compliant individuals. In this paper, we report on the findings specific to the role of family and gender relations and how they affect compliance. The sample comprised 21 men and 22 women; 24 complied with treatment while 19 did not. Gender relations emerged as a key theme in access, uptake and compliance with MDA. The view that the husband, as head of household, had the power, control, and in some cases the responsibility to influence whether his wife took the medication was common among both men and women. Gender also affected priorities for health care provision in the household as well as overall decision making regarding health in the household. Four models of responsibility for health decision making emerged: (i) responsibility resting primarily with the husband; (ii) responsibility resting primarily with the wife; (iii) responsibility shared equally by both husband and wife; and (iv) responsibility autonomously assumed by each individual for his or her own self, regardless of the course of action of the other spouse. (i) Gender relations and social hierarchy influence compliance with LF treatment because they inherently affect decisions taken within the household regarding health; (ii) health care interventions need to take account of the complexity of gender roles; (iii) the fact that women's power tends to be implicit and not overtly recognised in the household or the community has important implications for health care interventions; (iv

[Loa loa filariasis in Italy: review of the literature with a clinical report].

PubMed

Sgrelli, Alessio; De Socio, Giuseppe Vittorio Luigi; Papili, Rita; D'Annibale, Maria Letizia; Baldelli, Franco

2011-09-01

We present the case of an asymptomatic Loa loa disease in a 28-year-old Nigerian man living in Italy for 5 years. The man was admitted to our clinic for an occasional identification of hypereosinophilia (white blood cell count 5440/mmc, eosinophil 42%) and the presence of microfilaria at an hemoscopic evaluation. The diagnosis was made by testing the diurnal peripheral blood that showed a parasitaemia of 7000 microfilia/mL. The patient was treated with ivermectin 12 mg on the first day followed by albendazole 400 mg every 12 hours for 21 days with a reduction but no negativization of the parasitaemia and no collateral effect. Filariasis should be considered in all patients who come from or have stayed in endemic areas or who present alterations in the leukocyte formula, including hypereosinophilia, or some unexplainable allergic disorders. The lab diagnosis can be conducted through a hemoscopic test or directly with the identification of the adult worm, whereas the parasitaemia can be evaluated only through a hemoscopic test. The therapy can be non-conclusive or carried out with difficulty as finding diethylcarbamazine may be a hard task or potentially fatal anaphylactic reactions may occur.

Chemical composition, toxicity and non-target effects of Pinus kesiya essential oil: An eco-friendly and novel larvicide against malaria, dengue and lymphatic filariasis mosquito vectors.

PubMed

Govindarajan, Marimuthu; Rajeswary, Mohan; Benelli, Giovanni

2016-07-01

Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide, with special reference to tropical and subtropical countries. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, the mosquito larvicidal activity of Pinus kesiya leaf essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the P. kesiya EO contained 18 compounds. Major constituents were α-pinene, β-pinene, myrcene and germacrene D. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus, with LC50 values of 52, 57, and 62µg/ml, respectively. Notably, the EO was safer towards several aquatic non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 4135 to 8390µg/ml. Overall, this research adds basic knowledge to develop newer and safer natural larvicides from Pinaceae plants against malaria, dengue and filariasis mosquito vectors. Copyright © 2016 Elsevier Inc. All rights reserved.

Loss of sensitivity of immunochromatographic test (ICT) for lymphatic filariasis diagnosis in low prevalence settings: consequence in the monitoring and evaluation procedures.

PubMed

Gounoue-Kamkumo, Raceline; Nana-Djeunga, Hugues C; Bopda, Jean; Akame, Julie; Tarini, Ann; Kamgno, Joseph

2015-12-23

Diagnostic tools for lymphatic filariasis (LF) elimination programs are useful in mapping the distribution of the disease, delineating areas where mass drug administrations (MDA) are required, and determining when to stop MDA. The prevalence and burden of LF have been drastically reduced following mass treatments, and the evaluation of the performance of circulating filarial antigen (CFA)-based assays was acknowledged to be of high interest in areas with low residual LF endemicity rates after multiple rounds of MDA. The objective of this study was therefore to evaluate the immunochromatographic test (ICT) sensitivity in low endemicity settings and, specifically, in individuals with low intensity of lymphatic filariasis infection. To perform this study, calibrated thick blood smears, ICT and Og4C3 enzyme-linked immunosorbent assay (ELISA) were carried out by night to identify Wuchereria bancrofti microfilarial and circulating filarial antigen carriers. A threshold determination assay regarding ICT and ELISA was performed using serial plasma dilutions from individuals with positive microfilarial counts. All individuals harbouring microfilariae (positive blood films) were detected by ICT and ELISA, but among individuals positive for ELISA, only 35.7 % of them were detected using ICT (Chi square: 4.57; p-value = 0.03), indicating a moderate agreement between both tests (kappa statistics = 0.49). Threshold determination analyses showed that ELISA was still positive at the last plasma dilution with negative ICT result. These findings suggest a loss of sensitivity for ICT in low endemicity settings, especially in people exhibiting low levels of circulating filarial antigen, raising serious concern regarding the monitoring and evaluation procedures in the framework of LF elimination program.

Biosynthesis, mosquitocidal and antibacterial properties of Toddalia asiatica-synthesized silver nanoparticles: do they impact predation of guppy Poecilia reticulata against the filariasis mosquito Culex quinquefasciatus?

PubMed

Murugan, Kadarkarai; Venus, Joseph Selvaraj Eugine; Panneerselvam, Chellasamy; Bedini, Stefano; Conti, Barbara; Nicoletti, Marcello; Sarkar, Santosh Kumar; Hwang, Jiang-Shiou; Subramaniam, Jayapal; Madhiyazhagan, Pari; Kumar, Palanisamy Mahesh; Dinesh, Devakumar; Suresh, Udaiyan; Benelli, Giovanni

2015-11-01

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Furthermore, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. In this study, silver nanoparticles (AgN) were biosynthesized a cheap aqueous extract of T. asiatica leaves as reducing and stabilizing agent. The formation of nanoparticle was confirmed by surface Plasmon resonance band illustrated in UV-vis spectrophotometer. AgN were characterized by FTIR, SEM, EDX, and XRD analyses. AgN were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and their mean size was 25-30 nm. T. asiatica aqueous extract and green-synthesized AgN showed excellent larvicidal and pupicidal toxicity against the filariasis vector Culex quinqufasciatus, both in laboratory and field experiments. AgN LC50 ranged from 16.48 (I instar larvae) to 31.83 ppm (pupae). T. asiatica-synthesized were also highly effective in inhibiting growth of Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. Lastly, we evaluated if sublethal doses of nanoparticles affect predation rates of fishes, Poecilia reticulata, against C. quinquefasciatus. In AgN-contaminated environment, predation of guppies against mosquito larvae was slightly higher over normal laboratory conditions. Overall, this study highlighted that T. asiatica-synthesized AgN are easy to produce, stable over time, and may be employed at low dosages to reduce populations of filariasis vectors, without detrimental effects on predation rates of mosquito natural enemies.

How elimination of lymphatic filariasis as a public health problem in the Kingdom of Cambodia was achieved.

PubMed

Khieu, Virak; Or, Vandine; Tep, Chhakda; Odermatt, Peter; Tsuyuoka, Reiko; Char, Meng Chuor; Brady, Molly A; Sidwell, Joshua; Yajima, Aya; Huy, Rekol; Ramaiah, Kapa D; Muth, Sinuon

2018-02-20

Endemicity of lymphatic filariasis (LF) in Cambodia was proven in 1956 when microfilariae were detected in mosquitos in the Kratié province. In 2001, an extensive study confirmed the presence of both Brugia malayi and Wuchereria bancrofti microfilariae. In 2003, the Ministry of Health established a national task force to develop policies and strategies for controlling and eliminating neglected tropical diseases (NTDs), with the goal of eliminating LF by 2015. This article summarizes the work accomplished to eliminate LF as a public health problem in Cambodia. The National Program to Eliminate Lymphatic Filariasis made excellent progress in the goal towards elimination due to strong collaboration between ministries, intensive supervision by national staff, and advocacy for mobilization of internal and external resources. Mass drug administration (MDA) with diethylcarbamazine citrate and albendazole was conducted in six implementation units, achieving > 70% epidemiological coverage for five consecutive rounds, from 2005 to 2009. In 2006, in 14 provinces, healthcare workers developed a line list of lymphedema and hydrocele patients, many of whom were > 40 years old and had been affected by LF for many years. The national program also trained healthcare workers and provincial and district staff in morbidity management and disability prevention, and designated health centers to provide care for lymphedema and acute attack. Two reference hospitals were designated to administer hydrocele surgery. Effectiveness of MDA was proven with transmission assessment surveys. These found that less than 1% of school children had antigenemia in 2010, which fell to 0% in both 2013 and 2015. A separate survey in one province in 2015 using Brugia Rapid tests to test for LF antibody found one child positive among 1677 children. The list of chronic LF patients was most recently updated and confirmed in 2011-2012, with 32 lymphoedema patients and 17 hydrocele patients listed. All

The economic benefits resulting from the first 8 years of the Global Programme to Eliminate Lymphatic Filariasis (2000-2007).

PubMed

Chu, Brian K; Hooper, Pamela J; Bradley, Mark H; McFarland, Deborah A; Ottesen, Eric A

2010-06-01

Between 2000-2007, the Global Programme to Eliminate Lymphatic Filariasis (GPELF) delivered more than 1.9 billion treatments to nearly 600 million individuals via annual mass drug administration (MDA) of anti-filarial drugs (albendazole, ivermectin, diethylcarbamazine) to all at-risk for 4-6 years. Quantifying the resulting economic benefits of this significant achievement is important not only to justify the resources invested in the GPELF but also to more fully understand the Programme's overall impact on some of the poorest endemic populations. To calculate the economic benefits, the number of clinical manifestations averted was first quantified and the savings associated with this disease prevention then analyzed in the context of direct treatment costs, indirect costs of lost-labor, and costs to the health system to care for affected individuals. Multiple data sources were reviewed, including published literature and databases from the World Health Organization, International Monetary Fund, and International Labour Organization An estimated US$21.8 billion of direct economic benefits will be gained over the lifetime of 31.4 million individuals treated during the first 8 years of the GPELF. Of this total, over US$2.3 billion is realized by the protection of nearly 3 million newborns and other individuals from acquiring lymphatic filariasis as a result of their being born into areas freed of LF transmission. Similarly, more than 28 million individuals already infected with LF benefit from GPELF's halting the progression of their disease, which results in an associated lifetime economic benefit of approximately US$19.5 billion. In addition to these economic benefits to at-risk individuals, decreased patient services associated with reduced LF morbidity saves the health systems of endemic countries approximately US$2.2 billion. MDA for LF offers significant economic benefits. Moreover, with favorable program implementation costs (largely a result of the sustained

National Mass Drug Administration Costs for Lymphatic Filariasis Elimination

PubMed Central

Goldman, Ann S.; Guisinger, Victoria H.; Aikins, Moses; Amarillo, Maria Lourdes E.; Belizario, Vicente Y.; Garshong, Bertha; Gyapong, John; Kabali, Conrad; Kamal, Hussein A.; Kanjilal, Sanjat; Kyelem, Dominique; Lizardo, Jefrey; Malecela, Mwele; Mubyazi, Godfrey; Nitièma, P. Abdoulaye; Ramzy, Reda M. R.; Streit, Thomas G.; Wallace, Aaron; Brady, Molly A.; Rheingans, Richard; Ottesen, Eric A.; Haddix, Anne C.

2007-01-01

Background Because lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk. Methodology/Principal Findings To obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented – generally 60%–90% of program operation costs, excluding costs of donated medications. Conclusions/Significance MDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones. PMID:17989784

Albendazole and antibiotics synergize to deliver short-course anti-Wolbachia curative treatments in preclinical models of filariasis

PubMed Central

Sharma, Raman; Al Jayoussi, Ghaith; Tyrer, Hayley E.; Gamble, Joanne; Hayward, Laura; Priestley, Richard S.; Murphy, Emma A.; Davies, Jill; Waterhouse, David; Cook, Darren A. N.; Clare, Rachel H.; Cassidy, Andrew; Steven, Andrew; Johnston, Kelly L.; McCall, John; Ford, Louise; Hemingway, Janet; Ward, Stephen A.

2017-01-01

Elimination of filariasis requires a macrofilaricide treatment that can be delivered within a 7-day period. Here we have identified a synergy between the anthelmintic albendazole (ABZ) and drugs depleting the filarial endosymbiont Wolbachia, a proven macrofilaricide target, which reduces treatment from several weeks to 7 days in preclinical models. ABZ had negligible effects on Wolbachia but synergized with minocycline or rifampicin (RIF) to deplete symbionts, block embryogenesis, and stop microfilariae production. Greater than 99% Wolbachia depletion following 7-day combination of RIF+ABZ also led to accelerated macrofilaricidal activity. Thus, we provide preclinical proof-of-concept of treatment shortening using antibiotic+ABZ combinations to deliver anti-Wolbachia sterilizing and macrofilaricidal effects. Our data are of immediate public health importance as RIF+ABZ are registered drugs and thus immediately implementable to deliver a 1-wk macrofilaricide. They also suggest that novel, more potent anti-Wolbachia drugs under development may be capable of delivering further treatment shortening, to days rather than weeks, if combined with benzimidazoles. PMID:29078351

The Effect of Hygiene-Based Lymphedema Management in Lymphatic Filariasis-Endemic Areas: A Systematic Review and Meta-analysis

PubMed Central

Stocks, Meredith E.; Freeman, Matthew C.; Addiss, David G.

2015-01-01

Background Lymphedema of the leg and its advanced form, known as elephantiasis, are significant causes of disability and morbidity in areas endemic for lymphatic filariasis (LF), with an estimated 14 million persons affected worldwide. The twin goals of the World Health Organization’s Global Program to Eliminate Lymphatic Filariasis include interrupting transmission of the parasitic worms that cause LF and providing care to persons who suffer from its clinical manifestations, including lymphedema—so-called morbidity management and disability prevention (MMDP). Scaling up of MMDP has been slow, in part because of a lack of consensus about the effectiveness of recommended hygiene-based interventions for clinical lymphedema. Methods and Findings We conducted a systemic review and meta-analyses to estimate the effectiveness of hygiene-based interventions on LF-related lymphedema. We systematically searched PubMed, Embase, ISI Web of Knowledge, MedCarib, Lilacs, REPIDISCA, DESASTRES, and African Index Medicus databases through March 23, 2015 with no restriction on year of publication. Studies were eligible for inclusion if they (1) were conducted in an area endemic for LF, (2) involved hygiene-based interventions to manage lymphedema, and (3) assessed lymphedema-related morbidity. For clinical outcomes for which three or more studies assessed comparable interventions for lymphedema, we conducted random-effects meta-analyses. Twenty-two studies met the inclusion criteria and two meta-analyses were possible. To evaluate study quality, we developed a set of criteria derived from the GRADE methodology. Publication bias was assessed using funnel plots. Participation in hygiene-based lymphedema management was associated with a lower incidence of acute dermatolymphagioadenitis (ADLA), (Odds Ratio 0.32, 95% CI 0.25–0.40), as well as with a decreased percentage of patients reporting at least one episode of ADLA during follow-up (OR 0.29, 95% CI 0.12–0.47). Limitations

The Effect of Hygiene-Based Lymphedema Management in Lymphatic Filariasis-Endemic Areas: A Systematic Review and Meta-analysis.

PubMed

Stocks, Meredith E; Freeman, Matthew C; Addiss, David G

2015-10-01

Lymphedema of the leg and its advanced form, known as elephantiasis, are significant causes of disability and morbidity in areas endemic for lymphatic filariasis (LF), with an estimated 14 million persons affected worldwide. The twin goals of the World Health Organization's Global Program to Eliminate Lymphatic Filariasis include interrupting transmission of the parasitic worms that cause LF and providing care to persons who suffer from its clinical manifestations, including lymphedema-so-called morbidity management and disability prevention (MMDP). Scaling up of MMDP has been slow, in part because of a lack of consensus about the effectiveness of recommended hygiene-based interventions for clinical lymphedema. We conducted a systemic review and meta-analyses to estimate the effectiveness of hygiene-based interventions on LF-related lymphedema. We systematically searched PubMed, Embase, ISI Web of Knowledge, MedCarib, Lilacs, REPIDISCA, DESASTRES, and African Index Medicus databases through March 23, 2015 with no restriction on year of publication. Studies were eligible for inclusion if they (1) were conducted in an area endemic for LF, (2) involved hygiene-based interventions to manage lymphedema, and (3) assessed lymphedema-related morbidity. For clinical outcomes for which three or more studies assessed comparable interventions for lymphedema, we conducted random-effects meta-analyses. Twenty-two studies met the inclusion criteria and two meta-analyses were possible. To evaluate study quality, we developed a set of criteria derived from the GRADE methodology. Publication bias was assessed using funnel plots. Participation in hygiene-based lymphedema management was associated with a lower incidence of acute dermatolymphagioadenitis (ADLA), (Odds Ratio 0.32, 95% CI 0.25-0.40), as well as with a decreased percentage of patients reporting at least one episode of ADLA during follow-up (OR 0.29, 95% CI 0.12-0.47). Limitations included high heterogeneity across studies

A mathematical model for long-term effect of diethylcarbamazine-albendazole mass drug administration on lymphatic filariasis

NASA Astrophysics Data System (ADS)

Tasman, H.; Supali, T.; Supriatna, A. K.; Nuraini, N.; Soewono, E.

2015-03-01

In this paper we discuss a mathematical model for the transmission of lymphatic filariasis disease. The human population is divided into susceptible, latent, acute and chronic subpopulations. Treatment is carried out within the scheme of mass drug administration (MDA) by giving the diethylcarbamazine (DEC) and albendazole (ALB) to all individuals. In the model, we assume that the treatments have direct killing effect to microfilariae, increase of immune-mediated effect. The treated individuals are assumed to remain susceptible to the disease. This is due to the fact that the treatment is only partially effective against macrofilaria. Simulations of the model reveals that DEC-ALB treatment does give significant reduction of acute and chronic compartments at the end of the treatment period and slow down the growth after the treatment before eventually tend to the endemic state. It showed that repeated treatment during MDA is effective to decrease the transmission. This suggests that terminating MDA program after a long period of its application may still effective in controlling the disease.

Factors responsible for coverage and compliance in mass drug administration during the programme to eliminate lymphatic filariasis in the East Godavari District, South India.

PubMed

Babu, B V; Satyanarayana, K

2003-04-01

The paper attempts to report the factors responsible for the coverage and compliance of mass diethylcarbamazine citrate (DEC) administration, during the programme to eliminate lymphatic filariasis in the East Godavari District of Andhra Pradesh, India. The evaluation survey indicates that single dose DEC was received by 77% and taken by 64% of eligible people. Reasons for non-reception and non-consumption of the drug at household level were identified. The factors that influenced the coverage and compliance of treatment are broadly categorized as health services related, community related and drug related factors. The study identified some key factors to be followed for the success of the programme.

Stigma reduction and improved knowledge and attitudes towards filariasis using a comic book for children.

PubMed

el-Setouhy, Maged A; Rio, Francisco

2003-04-01

WHO has initiated a global program for lymphatic filariasis (LF) elimination by year 2020. A comic book was designed to improve knowledge and attitudes of Egyptian school children, which included messages on the acceptability of Mass Drug Administration (MDA) and stigma reduction. Comic book administration significantly reduced the fear of the studied children from LF as a killer disease. It helped in positively changing the attitudes of the children towards Elephantiasis patients (p-value <.001). The comic book also reduced the number of children who had earlier stated that they would avoid someone with LF. Knowledge about the ability of treating and preventing LF was also significantly increased among the children after reading the comic book. Moreover, comic book reading helped in raising the awareness towards MDA as the method of choice in preventing LF. Most of the children liked the comic book and its contents. Importantly, 96.2% found this book easy to understand. Many of relatives and friends read the comic book within 2 weeks after distribution. A well-accepted comic book for children is a proven way to reduce stigma and increase knowledge about disease prevention and treatment.

Costs of Transmission Assessment Surveys to Provide Evidence for the Elimination of Lymphatic Filariasis.

PubMed

Brady, Molly A; Stelmach, Rachel; Davide-Smith, Margaret; Johnson, Jim; Pou, Bolivar; Koroma, Joseph; Frimpong, Kingsley; Weaver, Angela

2017-02-01

To reach the global goal of elimination of lymphatic filariasis as a public health problem by 2020, national programs will have to implement a series of transmission assessment surveys (TAS) to determine prevalence of the disease by evaluation unit. It is expected that 4,671 surveys will be required by 2020. Planning in advance for the costs associated with these surveys is essential to ensure that the required resources are available for this essential program activity. Retrospective cost data was collected from reports from 13 countries which implemented a total of 105 TAS surveys following a standardized World Health Organization (WHO) protocol between 2012 and 2014. The median cost per survey was $21,170 (including the costs for rapid diagnostic tests [RDTs]) and $9,540 excluding those costs. Median cost per cluster sampled (without RDT costs) was $101. Analysis of costs (excluding RDTs) by category showed that the main cost drivers were personnel and travel. Transmission assessment surveys are critical to collect evidence to validate elimination of LF as a public health problem. National programs and donors can use the costing results to adequately plan and forecast the resources required to undertake the necessary activities to conduct high-quality transmission assessment surveys.

Assessing transmission of lymphatic filariasis using parasitologic, serologic, and entomologic tools after mass drug administration in American Samoa.

PubMed

Mladonicky, Janice M; King, Jonathan D; Liang, Jennifer L; Chambers, Eric; Pa'au, Molisamoa; Schmaedick, Mark A; Burkot, Thomas R; Bradley, Mark; Lammie, Patrick J

2009-05-01

Assessing the interruption of lymphatic filariasis transmission after annual mass drug administration (MDA) requires a better understanding of how to interpret results obtained with the available diagnostic tools. We conducted parasitologic, serologic, and entomologic surveys in three villages in American Samoa after sentinel site surveys suggested filarial antigen prevalence was < 1% after five annual MDAs with diethylcarbamazine and albendazole. Antigen and antifilarial antibody prevalence ranged from 3.7% to 4.6% and from 12.5% to 14.9%, respectively, by village. Only one person was microfilaria positive. Although no children less than 10 years of age were antigen positive, antifilarial antibody prevalence in this age group was 5.1% and antibody-positive children were detected in all three villages. Wuchereria bancrofti-infected mosquitoes were also detected in all three villages. Thus, monitoring of infections in mosquitoes and antifilarial antibody levels in children may serve as indicators of local transmission and be useful for making decisions about program endpoints.

Carbon and silver nanoparticles in the fight against the filariasis vector Culex quinquefasciatus: genotoxicity and impact on behavioral traits of non-target aquatic organisms.

PubMed

Murugan, Kadarkarai; Nataraj, Devaraj; Madhiyazhagan, Pari; Sujitha, Vasu; Chandramohan, Balamurugan; Panneerselvam, Chellasamy; Dinesh, Devakumar; Chandirasekar, Ramachandran; Kovendan, Kalimuthu; Suresh, Udaiyan; Subramaniam, Jayapal; Paulpandi, Manickam; Vadivalagan, Chithravel; Rajaganesh, Rajapandian; Wei, Hui; Syuhei, Ban; Aziz, Al Thabiani; Alsalhi, Mohamad Saleh; Devanesan, Sandhanasamy; Nicoletti, Marcello; Canale, Angelo; Benelli, Giovanni

2016-03-01

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. The Culex genus, with special reference to Culex quinquefasciatus, comprises the most common vectors of filariasis across urban and semi-urban areas of Asia. In recent years, important efforts have been conducted to propose green-synthesized nanoparticles as a valuable alternative to synthetic insecticides. However, the mosquitocidal potential of carbon nanoparticles has been scarcely investigated. In this study, the larvicidal and pupicidal activity of carbon nanoparticle (CNP) and silver nanoparticle (AgNP) was tested against Cx. quinquefasciatus. UV-Vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, and Raman analysis confirmed the rapid and cheap synthesis of carbon and silver nanoparticles. In laboratory assays, LC50 (lethal concentration that kills 50 % of the exposed organisms) values ranged from 8.752 ppm (first-instar larvae) to 18.676 ppm (pupae) for silver nanoparticles and from 6.373 ppm (first-instar larvae) to 14.849 ppm (pupae) for carbon nanoparticles. The predation efficiency of the water bug Lethocerus indicus after a single treatment with low doses of silver and carbon nanoparticles was not reduced. Moderate evidence of genotoxic effects induced by exposure to carbon nanoparticles was found on non-target goldfish, Carassius auratus. Lastly, the plant extract used for silver nanosynthesis was tested for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity. Overall, our results pointed out that AgNP and CNP can be a candidate for effective tools to reduce larval and pupal populations of filariasis vectors, with reduced genotoxicity and impact on behavioral traits of other aquatic organisms sharing the same ecological

PREVALENCE OF LYMPHATIC FILARIASIS, MALARIA AND SOIL TRANSMITTED HELMINTHIASIS IN A COMMUNITY OF BARDIYA DISTRICT, WESTERN NEPAL.

PubMed

Ranjitkar, Samir; Alifrangis, Michael; Adhikari, Madhav; Olsen, Annette; Simonsen, Paul E; Meyrowitsch, Dan Wolf

2014-11-01

Lymphatic filariasis (LF), malaria and soil transmitted helminthiasis (STH) cause major health problems in Nepal, but in spite of this very few stud- ies have been carried out on these parasitic infections in Nepal. A cross sectional survey of all three categories of parasitic infections was carried out in Deuda- kala Village of Bardiya District, western Nepal. A total of 510 individuals aged 5 years and above were examined from finger prick blood for circulating filarial antigen (CFA), malaria antigen using a rapid diagnostic test (RDT), and malaria DNA using a PCR-based assay. In addition, 317 individuals were examined for soil-transmitted helminth (STH) eggs by the Kato-Katz technique. Prevalence of LF, malaria (antigen) and STH infection was 25.1%, 0.6% and 18.3%, respectively. PCR analysis did not detect any additional malaria cases. The prevalence of LF and STH infections differ significantly among different age groups and ethnic communities. The high prevalence of LF in the community studied indicates an immediate need for implementing a mass drug administration program for its control in this particular geographical area of Nepal.

[Prevalence of canine filariasis by Dirofilaria immitis and Dipetalonema reconditum in Maceió, Alagoas State, Brazil].

PubMed

Brito, A C; Vila-Nova, M C; Martins Rocha, D A; Gomes Costa, L; Pinheiro de Almeida, W A; da Silva Viana, L; Ramalho Lopes, R; Fontes, G; da Rocha, E M; Regis, L

2001-01-01

A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,519 dogs from Maceió and two coastal areas in the State of Alagoas, Northeast Brazil, from 1995 to 1999, by testing for microfilariae in blood. All blood samples were from exclusively domiciled dogs with a known history, showing that the infections were autochthonous, confirming transmission of canine filariasis in these areas. In Greater Metropolitan Maceió, 15 (1.3%) microfilaremic dogs were detected with D. immitis and 15 (1,3%) with D. reconditum. In the southern coastal area there was an estimated prevalence of 12.7% for D. immitis. D. immitis and D. reconditum microfilaria were 298.1 micrometer and 249.2 micrometer long and 7.3 micrometer and 4.4 micrometer wide, respectively. A Witness immunotest that detects D. immitis antigen was used to confirm parasitological results and reveal occult dirofilariasis cases. Of the total 6,579 females examined, 8 (0.1%) Culex quinquefasciatus were observed to be naturally infected with D. immitis larvae. These results proved dirofilariasis transmission in Maceió and demonstrated D. reconditum in the same geographic area.

Prospects of developing a prophylactic vaccine against human lymphatic filariasis - evaluation of protection in non-human primates.

PubMed

Khatri, Vishal; Chauhan, Nikhil; Vishnoi, Kanchan; von Gegerfelt, Agneta; Gittens, Courtney; Kalyanasundaram, Ramaswamy

2018-06-06

Lymphatic filariasis (LF) affects 120 million people around the world and another 856 million people are at risk of acquiring the infection. Mass Drug Administration (MDA) spearheaded by the World Health Organization is the only current strategy to control this infection. Recent reports suggest that despite several rounds of MDA, elimination has not been achieved and there is a need for more stringent control strategies for control of LF. An effective prophylactic vaccine combined with MDA has significant potential. Initial trials using a prophylactic trivalent recombinant Brugia malayi heat shock protein 12.6, abundant larval transcript -2 and tetraspanin large extra-cellular loop (rBmHAT) vaccine developed in our laboratory conferred only 35% protection in macaques. Therefore, the focus of the present study was to improve the current vaccine formulation to obtain better protection in non-human primates. We made two modifications to the current formulation: (i) the addition of another antigen, thioredoxin peroxidase-2 (TPX-2) to make it a tetravalent vaccine (rBmHAXT) and (ii) the inclusion of an adjuvant; AL019 (alum plus glucopyranosyl lipid adjuvant-stable emulsion) that is known to promote a balanced Th1/Th2 response. A double-blinded vaccination trial was performed with 40 macaques that were divided into three treatment groups and one control group (n = 10/group). Vaccinated animals received 4 immunisations at 1 month intervals with 150 µg/ml of rBmHAT plus alum, rBmHAT plus AL019 or rBmHAXT plus AL019. Control animals received AL019 only. All vaccinated macaques developed significant (P ≤ 0.003) titers of antigen-specific IgG antibodies (1:20,000) compared with the controls. One month after the last dose, all macaques were challenged s.c. with 130-180 B. malayi L3s. Our results showed that seven out of 10 (70%) of macaques given the improved rBmHAXT vaccine did not develop the infection compared with AL019 controls, of which seven out of 10

Larvicidal and repellent potential of Zingiber nimmonii (J. Graham) Dalzell (Zingiberaceae) essential oil: an eco-friendly tool against malaria, dengue, and lymphatic filariasis mosquito vectors?

PubMed

Govindarajan, Marimuthu; Rajeswary, Mohan; Arivoli, Subramanian; Tennyson, Samuel; Benelli, Giovanni

2016-05-01

Mosquitoes (Diptera: Culicidae) are important vectors of terms of public health relevance, especially in tropical and sub-tropical regions. The continuous and indiscriminate use of conventional pesticides for the control of mosquito vectors has resulted in the development of resistance and negative impacts on non-target organisms and the environment. Therefore, there is a need for development of effective mosquito control tools. In this study, the larvicidal and repellent activity of Zingiber nimmonii rhizome essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti, and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy (GC-MS). GC-MS revealed that the Z. nimmonii EO contained at least 33 compounds. Major constituents were myrcene, β-caryophyllene, α-humulene, and α-cadinol. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus, with LC50 values of 41.19, 44.46, and 48.26 μg/ml, respectively. Repellency bioassays at 1.0, 2.0, and 5.0 mg/cm(2) of Z. nimmonii EO gave 100 % protection up to 120, 150, and 180 min. against An. stephensi, followed by Ae. aegypti (90, 120, and 150 min) and Cx. quinquefasciatus (60, 90, and 120 min). Furthermore, the EO was safer towards two non-target aquatic organisms, Diplonychus indicus and Gambusia affinis, with LC50 values of 3241.53 and 9250.12 μg/ml, respectively. Overall, this research adds basic knowledge to develop newer and safer natural larvicides and repellent from Zingiberaceae plants against malaria, dengue, and filariasis mosquito vectors.

Effect of 3 years of biannual mass drug administration with albendazole on lymphatic filariasis and soil-transmitted helminth infections: a community-based study in Republic of the Congo.

PubMed

Pion, Sébastien D S; Chesnais, Cédric B; Weil, Gary J; Fischer, Peter U; Missamou, François; Boussinesq, Michel

2017-07-01

The standard treatment strategy of mass drug administration with ivermectin plus albendazole for lymphatic filariasis cannot be applied in central Africa, because of the risk of serious adverse events in people with high Loa loa microfilaraemia. Thus, alternative strategies are needed. We investigated one such alternative strategy for mass drug administration for elimination of lymphatic filariasis and soil-transmitted helminth infections in Republic of the Congo. In 2012, we started a 3 year community trial of biannual mass administration of albendazole in a village in Republic of the Congo. All volunteering inhabitants aged 2 years or older were offered albendazole (400 mg) every 6 months. Infection with Wuchereria bancrofti was diagnosed with a rapid card immunochromatographic test for antigenaemia. People with antigenaemia were tested for microfilaraemia by night blood smears. Individuals were also tested for soil-transmitted helminth infections (ie, hookworm, Ascaris lumbricoides, Trichuris trichiura) with the Kato-Katz method. Assessment surveys were done at 12, 24, and 36 months. The main outcome measure was change in infection rates from baseline to year 3. Therapeutic coverage was more than 80% in all six rounds of mass administration of albendazole. Between 2012 and 2015, W bancrofti antigenaemia and microfilaraemia rates in the community fell significantly, from 17·3% (95% CI 14·7-20·0) to 4·7% (3·3-6·6; p<0·0001) and from 5·3% (3·9-7·1) to 0·3% (0·1-1·2; p<0·0001), respectively. The geometric mean microfilaria count in microfilaraemic people fell from 199·4 (120·4-330·5) per mL in 2012 to 39·1 (95% CIs not computed) per mL in 2015 (p=0·0095). Hookworm infection was undetectable after 1 year. Between 2012 and 2015, the number of A lumbricoides eggs expelled per g of faeces fell from 9844·6 (8209·0-11 480·0) to 724·4 (340·7-1114·2; p<0·0001), and of T trichiura eggs from 1107·4 (878·5-1336·3) to 366·0 (255·7-476·2; p<0�

Lymphatic filariasis in Papua New Guinea: distribution at district level and impact of mass drug administration, 1980 to 2011

PubMed Central

2013-01-01

Background Lymphatic filariasis (LF) caused by Wuchereria bancrofti is present at high prevalence in some parts of Papua New Guinea. However, there has been no rigorous data-based representative assessment of nationwide prevalence of LF. The LF programme has been daunted by the scope of the problem, and progress on mass drug administration (MDA) has been slow and lacking in resources. Methods A systematic literature review identified LF surveys in Papua New Guinea between 1980 and 2011. Results were extracted by location, time period and test used (blood slide, immunochromatographic test (ICT) or Og4C3 ELISA) and combined by district. Three criteria schemes based on the Global Programme to Eliminate Lymphatic Filariasis guidelines, with modifications, were developed to classify and prioritize districts by prevalence level. Results of repeated surveys in the same sites were used to investigate the impact of MDA on LF prevalence over the time period. Results There were 312 distinct survey sites identified in 80 of the 89 districts over the 31-year period. The overall LF prevalence in the sites tested was estimated at 18.5 to 27.5% by blood slide for microfilariae (Mf), 10.1% to 12.9% by ICT and 45.4% to 48.8% by Og4C3. Biases in site selection towards areas with LF, and change in type of assay used, affected the prevalence estimates, but overall decline in prevalence over the time period was observed. Depending on the criteria used, 34 to 36 districts (population 2.7 to 2.9 million) were classed as high endemic (≥5% prevalence), 15 to 25 districts (1.7 to 1.9 million) as low endemic (<5%) and 20 to 31 (1.3 to 2.2 million) as non-endemic. Nine districts (0.7 million) had no information. The strong impact of MDA, especially on microfilaria (Mf) prevalence, was noted in sites with repeat surveys. Conclusions This analytical review of past surveys of LF in Papua New Guinea enables better estimation of the national burden, identifies gaps in knowledge, quantifies and

Experiences of a Community-Based Lymphedema Management Program for Lymphatic Filariasis in Odisha State, India: An Analysis of Focus Group Discussions with Patients, Families, Community Members and Program Volunteers

PubMed Central

Cassidy, Tali; Worrell, Caitlin M.; Little, Kristen; Prakash, Aishya; Patra, Inakhi; Rout, Jonathan; Fox, LeAnne M.

2016-01-01

Background Globally 68 million people are infected with lymphatic filariasis (LF), 17 million of whom have lymphedema. This study explores the effects of a lymphedema management program in Odisha State, India on morbidity and psychosocial effects associated with lymphedema. Methodology/Principal Findings Focus groups were held with patients (eight groups, separated by gender), their family members (eight groups), community members (four groups) and program volunteers (four groups) who had participated in a lymphedema management program for the past three years. Significant social, physical, and economic difficulties were described by patients and family members, including marriageability, social stigma, and lost workdays. However, the positive impact of the lymphedema management program was also emphasized, and many family and community members indicated that community members were accepting of patients and had some improved understanding of the etiology of the disease. Program volunteers and community members stressed the role that the program had played in educating people, though interestingly, local explanations and treatments appear to coexist with knowledge of biomedical treatments and the mosquito vector. Conclusions/Significance Local and biomedical understandings of disease can co-exist and do not preclude individuals from participating in biomedical interventions, specifically lymphedema management for those with lymphatic filariasis. There is a continued need for gender-specific psychosocial support groups to address issues particular to men and women as well as a continued need for improved economic opportunities for LF-affected patients. There is an urgent need to scale up LF-related morbidity management programs to reduce the suffering of people affected by LF. PMID:26849126

Experiences of a Community-Based Lymphedema Management Program for Lymphatic Filariasis in Odisha State, India: An Analysis of Focus Group Discussions with Patients, Families, Community Members and Program Volunteers.

PubMed

Cassidy, Tali; Worrell, Caitlin M; Little, Kristen; Prakash, Aishya; Patra, Inakhi; Rout, Jonathan; Fox, LeAnne M

2016-02-01

Globally 68 million people are infected with lymphatic filariasis (LF), 17 million of whom have lymphedema. This study explores the effects of a lymphedema management program in Odisha State, India on morbidity and psychosocial effects associated with lymphedema. Focus groups were held with patients (eight groups, separated by gender), their family members (eight groups), community members (four groups) and program volunteers (four groups) who had participated in a lymphedema management program for the past three years. Significant social, physical, and economic difficulties were described by patients and family members, including marriageability, social stigma, and lost workdays. However, the positive impact of the lymphedema management program was also emphasized, and many family and community members indicated that community members were accepting of patients and had some improved understanding of the etiology of the disease. Program volunteers and community members stressed the role that the program had played in educating people, though interestingly, local explanations and treatments appear to coexist with knowledge of biomedical treatments and the mosquito vector. Local and biomedical understandings of disease can co-exist and do not preclude individuals from participating in biomedical interventions, specifically lymphedema management for those with lymphatic filariasis. There is a continued need for gender-specific psychosocial support groups to address issues particular to men and women as well as a continued need for improved economic opportunities for LF-affected patients. There is an urgent need to scale up LF-related morbidity management programs to reduce the suffering of people affected by LF.

Situational analysis of lymphatic filariasis morbidity in Ahanta West District of Ghana.

PubMed

Stanton, Michelle C; Best, Abigail; Cliffe, Matthew; Kelly-Hope, Louise; Biritwum, Nana-Kwadwo; Batsa, Linda; Debrah, Alex

2016-02-01

Situational analysis of lymphatic filariasis (LF) morbidity and its management in Ahanta West, Ghana, to identify potential barrier to healthcare for LF patients. Lymphoedema and hydrocoele patients were identified by community health workers from a subset of villages, and were interviewed and participated in focus group discussions to determine their attitudes and practices towards managing their morbidity, and their perceived barriers to accessing care. Local health professionals were also interviewed to obtain their views on the availability of morbidity management services in the district. Sixty-two patients (34 lymphoedema and 28 hydrocoeles) and 13 local health professionals were included in the study. Lymphoedema patients predominantly self-managed their conditions, which included washing with soap and water (61.8%), and exercising the affected area (52.9%). Almost 65% of patients had sought medical assistance at some stage, but support was generally limited to receiving tablets (91%). Local health professionals reported rarely seeing lymphoedema patients, citing stigma and lack of provisions to assist patients as a reason for this. Almost half of hydrocoele patients (44%) chose not to seek medical assistance despite the negative impact it had on their lives. Whilst surgery itself is free with national health insurance, 63% those who had not sought treatment stated that indirect costs of surgery (travel costs, loss of earnings, etc.) were the most prohibitive factor to seeking treatment. The information obtained from this study should now be used to guide future morbidity strategies in building a stronger relationship between the local health services and LF patients, to ultimately improve patients' physical, psychological and economic wellbeing. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Predicting lymphatic filariasis transmission and elimination dynamics using a multi-model ensemble framework.

PubMed

Smith, Morgan E; Singh, Brajendra K; Irvine, Michael A; Stolk, Wilma A; Subramanian, Swaminathan; Hollingsworth, T Déirdre; Michael, Edwin

2017-03-01

Mathematical models of parasite transmission provide powerful tools for assessing the impacts of interventions. Owing to complexity and uncertainty, no single model may capture all features of transmission and elimination dynamics. Multi-model ensemble modelling offers a framework to help overcome biases of single models. We report on the development of a first multi-model ensemble of three lymphatic filariasis (LF) models (EPIFIL, LYMFASIM, and TRANSFIL), and evaluate its predictive performance in comparison with that of the constituents using calibration and validation data from three case study sites, one each from the three major LF endemic regions: Africa, Southeast Asia and Papua New Guinea (PNG). We assessed the performance of the respective models for predicting the outcomes of annual MDA strategies for various baseline scenarios thought to exemplify the current endemic conditions in the three regions. The results show that the constructed multi-model ensemble outperformed the single models when evaluated across all sites. Single models that best fitted calibration data tended to do less well in simulating the out-of-sample, or validation, intervention data. Scenario modelling results demonstrate that the multi-model ensemble is able to compensate for variance between single models in order to produce more plausible predictions of intervention impacts. Our results highlight the value of an ensemble approach to modelling parasite control dynamics. However, its optimal use will require further methodological improvements as well as consideration of the organizational mechanisms required to ensure that modelling results and data are shared effectively between all stakeholders. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Modelling variability in lymphatic filariasis: macrofilarial dynamics in the Brugia pahangi--cat model.

PubMed

Michael, E; Grenfell, B T; Isham, V S; Denham, D A; Bundy, D A

1998-01-22

A striking feature of lymphatic filariasis is the considerable heterogeneity in infection burden observed between hosts, which greatly complicates the analysis of the population dynamics of the disease. Here, we describe the first application of the moment closure equation approach to model the sources and the impact of this heterogeneity for macrofilarial population dynamics. The analysis is based on the closest laboratory equivalent of the life cycle and immunology of infection in humans--cats chronically infected with the filarial nematode Brugia pahangi. Two sets of long-term experiments are analysed: hosts given either single primary infections or given repeat infections. We begin by quantifying changes in the mean and aggregation of adult parasites (inversely measured by the negative binomial parameter, kappa in cohorts of hosts using generalized linear models. We then apply simple stochastic models to interpret observed patterns. The models and empirical data indicate that parasite aggregation tracks the decline in the mean burden with host age in primary infections. Conversely, in repeat infections, aggregation increases as the worm burden declines with experience of infection. The results show that the primary infection variability is consistent with heterogeneities in parasite survival between hosts. By contrast, the models indicate that the reduction in parasite variability with time in repeat infections is most likely due to the 'filtering' effect of a strong, acquired immune response, which gradually acts to remove the initial variability generated by heterogeneities in larval mortality. We discuss this result in terms of the homogenizing effect of host immunity-driven density-dependence on macrofilarial burden in older hosts.

Lymphatic filariasis and onchocerciasis prevention, treatment, and control costs across diverse settings: a systematic review.

PubMed

Keating, Joseph; Yukich, Joshua O; Mollenkopf, Sarah; Tediosi, Fabrizio

2014-07-01

The control and eventual elimination of neglected tropical disease (NTD) requires the expansion of interventions such as mass drug administration (MDA), vector control, diagnostic testing, and effective treatment. The purpose of this paper is to present the evidence base for decision-makers on the cost and cost-effectiveness of lymphatic filariasis (LF) and onchocerciasis prevention, treatment, and control. A systematic review of the published literature was conducted. All studies that contained primary or secondary data on costs or cost-effectiveness of prevention and control were considered. A total of 52 papers were included for LF and 24 papers were included for onchocerciasis. Large research gaps exist on the synergies and cost of integrating NTD prevention and control programs, as well as research on the role of health information systems, human resource systems, service delivery, and essential medicines and technology for elimination. The literature available on costs and cost-effectiveness of interventions is also generally older, extremely focal geographically and of limited usefulness for developing estimates of the global economic burden of these diseases and prioritizing among various intervention options. Up to date information on the costs and cost-effectiveness of interventions for LF and onchocerciasis prevention are needed given the vastly expanded funding base for the control and elimination of these diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

Toxicity of seaweed-synthesized silver nanoparticles against the filariasis vector Culex quinquefasciatus and its impact on predation efficiency of the cyclopoid crustacean Mesocyclops longisetus.

PubMed

Murugan, Kadarkarai; Benelli, Giovanni; Ayyappan, Suganya; Dinesh, Devakumar; Panneerselvam, Chellasamy; Nicoletti, Marcello; Hwang, Jiang-Shiou; Kumar, Palanisamy Mahesh; Subramaniam, Jayapal; Suresh, Udaiyan

2015-06-01

Nearly 1.4 billion people in 73 countries worldwide are threatened by lymphatic filariasis, a parasitic infection that leads to a disease commonly known as elephantiasis. Filariasis is vectored by mosquitoes, with special reference to the genus Culex. The main control tool against mosquito larvae is represented by treatments with organophosphates and insect growth regulators, with negative effects on human health and the environment. Recently, green-synthesized nanoparticles have been proposed as highly effective larvicidals against mosquito vectors. In this research, we attempted a reply to the following question: do green-synthesized nanoparticles affect predation rates of copepods against mosquito larvae? We proposed a novel method of seaweed-mediated synthesis of silver nanoparticles using the frond extract of Caulerpa scalpelliformis. The toxicity of the seaweed extract and silver nanoparticles was assessed against the filarial vector Culex quinquefasciatus. Then, we evaluated the predatory efficiency of the cyclopoid crustacean Mesocyclops longisetus against larval instars of C. quinquefasciatus in a nanoparticle-contaminated water environment. Green-synthesized silver nanoparticles were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). In mosquitocidal assays, the LC₅₀ values of the C. scalpelliformis extract against C. quinquefasciatus were 31.38 ppm (I), 46.49 ppm (II), 75.79 ppm (III), 102.26 ppm (IV), and 138.89 ppm (pupa), while LC₅₀ of silver nanoparticles were 3.08 ppm, (I), 3.49 ppm (II), 4.64 ppm (III), 5.86 ppm (IV), and 7.33 ppm (pupa). The predatory efficiency of the copepod M. longisetus in the control treatment was 78 and 59% against I and II instar larvae of C. quinquefasciatus. In a nanoparticle-contaminated environment, predation efficiency was 84 and 63%, respectively. Predation was higher against first instar larvae over other instars

Prevalence of and risk factors for malaria, filariasis, and intestinal parasites as single infections or co-infections in different settlements of Gabon, Central Africa.

PubMed

M'bondoukwé, Noé Patrick; Kendjo, Eric; Mawili-Mboumba, Denise Patricia; Koumba Lengongo, Jeanne Vanessa; Offouga Mbouoronde, Christelle; Nkoghe, Dieudonné; Touré, Fousseyni; Bouyou-Akotet, Marielle Karine

2018-01-30

Malaria, filariasis, and intestinal parasitic infections (IPIs) are common and frequently overlap in developing countries. The prevalence and predictors of these infections were investigated in three different settlements (rural, semi-urban, and urban) of Gabon. During cross-sectional surveys performed from September 2013 to June 2014, 451 individuals were interviewed. In addition, blood and stool samples were analysed for the presence of Plasmodium, filarial roundworm, intestinal protozoan, and helminth infections. Intestinal parasitic infections (61.1%), including intestinal protozoa (56.7%) and soil-transmitted helminths (STHs) (22.2%), predominated, whereas Plasmodium falciparum (18.8%), Loa loa (4.7%), and Mansonella perstans (1.1%) were less prevalent. Filariasis and STHs were mainly found in rural settlements, whereas a higher plasmodial infection prevalence rate was observed in the periurban area. The most common IPI was blastocystosis (48.6%), followed by ascaridiasis (13.7%), trichuriasis (11.8%), amoebiasis (9.3%), giardiasis (4.8%), and strongyloidiasis (3.7%). Hookworm was detected in one adult from rural Dienga. Adults had a higher prevalence of Blastocystis hominis and STHs, whereas Giardia duodenalis was more frequently observed among children aged below 5 years (P < 0.01). The polyparasitism rate was 41.5%, with 7.0% Plasmodium-IPIs and 1.8% Plasmodium-STH co-infections. The multivariate analysis showed that living in a suburban area, belonging to the age group of 5-15 years, having none or a secondary education, or having an open body water close to home were significant risk factors for malaria (P ≤ 0.01). For STH infections, identified risk factors were drinking untreated water and living in a rural area (P ≤ 0.04). No significant predictors were identified for IPIs and malaria-IPI co-infection. This study reports a high prevalence of IPIs and intestinal protozoa, but a low rate of malaria-IPI co-infections in the study sites

Repurposing Auranofin as a Lead Candidate for Treatment of Lymphatic Filariasis and Onchocerciasis

PubMed Central

Bulman, Christina A.; Bidlow, Chelsea M.; Lustigman, Sara; Cho-Ngwa, Fidelis; Williams, David; Rascón, Jr, Alberto A.; Tricoche, Nancy; Samje, Moses; Bell, Aaron; Suzuki, Brian; Lim, K. C.; Supakorndej, Nonglak; Supakorndej, Prasit; Wolfe, Alan R.; Knudsen, Giselle M.; Chen, Steven; Wilson, Chris; Ang, Kean-Hooi; Arkin, Michelle; Gut, Jiri; Franklin, Chris; Marcellino, Chris; McKerrow, James H.; Debnath, Anjan; Sakanari, Judy A.

2015-01-01

Two major human diseases caused by filariid nematodes are onchocerciasis, or river blindness, and lymphatic filariasis, which can lead to elephantiasis. The drugs ivermectin, diethylcarbamazine (DEC), and albendazole are used in control programs for these diseases, but are mainly effective against the microfilarial stage and have minimal or no effect on adult worms. Adult Onchocerca volvulus and Brugia malayi worms (macrofilariae) can live for up to 15 years, reproducing and allowing the infection to persist in a population. Therefore, to support control or elimination of these two diseases, effective macrofilaricidal drugs are necessary, in addition to current drugs. In an effort to identify macrofilaricidal drugs, we screened an FDA-approved library with adult worms of Brugia spp. and Onchocerca ochengi, third-stage larvae (L3s) of Onchocerca volvulus, and the microfilariae of both O. ochengi and Loa loa. We found that auranofin, a gold-containing drug used for rheumatoid arthritis, was effective in vitro in killing both Brugia spp. and O. ochengi adult worms and in inhibiting the molting of L3s of O. volvulus with IC50 values in the low micromolar to nanomolar range. Auranofin had an approximately 43-fold higher IC50 against the microfilariae of L. loa compared with the IC50 for adult female O. ochengi, which may be beneficial if used in areas where Onchocerca and Brugia are co-endemic with L. loa, to prevent severe adverse reactions to the drug-induced death of L. loa microfilariae. Further testing indicated that auranofin is also effective in reducing Brugia adult worm burden in infected gerbils and that auranofin may be targeting the thioredoxin reductase in this nematode. PMID:25700363

Single multivalent vaccination boosted by trickle larval infection confers protection against experimental lymphatic filariasis

PubMed Central

Joseph, SK; Ramaswamy, K

2013-01-01

The multivalent vaccine BmHAT, consisting of the Brugia malayi infective larval (L3) antigens heat shock protein12.6 (HSP12.6), abundant larval transcript-2 (ALT-2) and tetraspanin large extra cellular loop (TSP-LEL), was shown to be protective in rodent models from our laboratory. We hypothesize that since these antigens were identified using protective antibodies from immune endemic normal individuals, the multivalent vaccine can be augmented by natural L3 infections providing protection to the vaccinated host. This hypothesis was tested using single dose of DNA and Protein or Protein alone of the BmHAT vaccination in gerbils followed by live trickle L3 infection as booster dose. Vaccine-induced protection in gerbils was determined by worm establishment, micropore chamber assay and by antibody dependant cell cytotoxicity (ADCC) assay. Results were compared with the traditional prime-boost vaccination regimen. Gerbils vaccinated with BmHAT and boosted with L3 trickle infection were protected 51% (BmHAT DNA-Protein) and 48% (BmHAT Protein) respectively. BmHAT vaccination plus L3 trickle booster generated significant titer of antigen-specific IgG antibodies comparable to the traditional prime boost vaccination approach. BmHAT vaccination plus L3 trickle booster also generated antigen-specific cells in the spleen of vaccinated animals and these cells secreted predominantly IFN-γ and IL-4 in response to the vaccine antigens. These studies thus show that single dose of BmHAT multivalent vaccination followed by L3 trickle booster infection can confer significant protection against lymphatic filariasis. PMID:23735679

Impact of chronic lymphatic filariasis on quantity and quality of productive work among weavers in an endemic village from India.

PubMed

Babu, B V; Swain, B K; Rath, K

2006-05-01

To assess the impact of hydrocele and lymphoedema on the quantity and quality of productive work of weavers. Case-control study in an endemic village in Andhra Pradesh, India. We collected qualitative data on work activities from cases and age- and sex-matched controls through informal discussions and observation. The mean (+/-standard deviation) daily work time of cases was 7.38 h (+/-2.47), significantly less than that of controls (8.17+/-2.41 h). Lost work time was equivalent to around 29 days of work in a year. Gender had significant influence on the mean number of working hours in this occupational group. Most cases could not weave, which is physically demanding, and preferred less strenuous tasks such as spinning, starching, dyeing or sizing. Hard physical labour constitutes 71.5% of total work time among patients and 83.7% in controls. As income also depends on the type of work, cases earn less. Filariasis has an adverse impact on the productivity of weavers, and morbidity management strategies and control programmes need to take this into account.

Larvicidal Activity of Cassia occidentalis (Linn.) against the Larvae of Bancroftian Filariasis Vector Mosquito Culex quinquefasciatus.

PubMed

Kumar, Deepak; Chawla, Rakesh; Dhamodaram, P; Balakrishnan, N

2014-01-01

Background & Objectives. The plan of this work was to study the larvicidal activity of Cassia occidentalis (Linn.) against the larvae of Culex quinquefasciatus. These larvae are the most significant vectors. They transmit the parasites and pathogens which cause a deadly disease like filariasis, dengue, yellow fever, malaria, Japanese encephalitis, chikungunya, and so forth, which are considered harmful towards the population in tropic and subtropical regions. Methods. The preliminary laboratory trail was undertaken to determine the efficacy of petroleum ether and N-butanol extract of dried whole plant of Cassia occidentalis (Linn.) belonging to the family Caesalpiniaceae at various concentrations against the late third instar larvae of Culex quinquefasciatus by following the WHO guidelines. Results. The results suggest that 100% mortality effect of petroleum ether and N-butanol extract of Cassia occidentalis (Linn.) was observed at 200 and 300 ppm (parts per million). The results obviously showed use of plants in insect control as an alternative method for minimizing the noxious effect of some pesticide compounds on the environment. Thus the extract of Cassia occidentalis (Linn.) is claimed as more selective and biodegradable agent. Conclusion. This study justified that plant Cassia occidentalis (Linn.) has a realistic mortality result for larvae of filarial vector. This is safe to individual and communities against mosquitoes. It is a natural weapon for mosquito control.

Persistent 'hotspots' of lymphatic filariasis microfilaraemia despite 14 years of mass drug administration in Ghana.

PubMed

Biritwum, Nana-Kwadwo; Yikpotey, Paul; Marfo, Benjamin K; Odoom, Samuel; Mensah, Ernest O; Asiedu, Odame; Alomatu, Bright; Hervie, Edward T; Yeboah, Abednego; Ade, Serge; Hinderaker, Sven G; Reid, Anthony; Takarinda, Kudakwashe C; Koudou, Benjamin; Koroma, Joseph B

2016-12-01

Among the 216 districts in Ghana, 98 were declared endemic for lymphatic filariasis in 1999 after mapping. Pursuing the goal of elimination, WHO recommends annual treatment using mass drugs administration (MDA) for at least 5 years. MDA was started in the country in 2001 and reached national coverage in 2006. By 2014, 69 districts had 'stopped-MDA' (after passing the transmission assessment survey) while 29 others remained with persistent microfilaraemia (mf) prevalence (≥1%) despite more than 11 years of MDA and were classified as 'hotspots'. An ecological study was carried out to compare baseline mf prevalence and anti-microfilaria interventions between hotspot and stopped-MDA districts. Baseline mf prevalence was significantly higher in hotspots than stopped-MDA districts (p<0.001). After three years of MDA, there was a significant decrease in mf prevalence in hotspot districts, but it was still higher than in stopped-MDA districts. The number of MDA rounds was slightly higher in hotspot districts (p<0.001), but there were no differences in coverage of MDA or long-lasting-insecticide-treated nets. The main difference in hotspots and stopped-MDA districts was a high baseline mf prevalence. This finding indicates that the recommended 5-6 rounds annual treatment may not achieve interruption of transmission. © The Author 2017. 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.

Loss of genetic diversity in Culex quinquefasciatus targeted by a lymphatic filariasis vector control program in Recife, Brazil.

PubMed

Cartaxo, Marina F S; Ayres, Constância F J; Weetman, David

2011-09-01

Recife is one of the largest cities in north-eastern Brazil and is endemic for lymphatic filariasis transmitted by Culex quinquefasciatus. Since 2003 a control program has targeted mosquito larvae by elimination of breeding sites and bimonthly application of Bacillus sphaericus. To assess the impact of this program on the local vector population we monitored the genetic diversity and differentiation of Cx. quinquefasciatus using microsatellites and a B. sphaericus-resistance associated mutation (cqm1(REC)) over a 3-year period. We detected a significant but gradual decline in allelic diversity, which, coupled with subtle temporal genetic structure, suggests a major impact of the control program on the vector population. Selection on cqm1(REC) does not appear to be involved with loss of neutral diversity from the population, with no temporal trend in resistant allele frequency and no correlation with microsatellite differentiation. The evidence for short-term genetic drift we detected suggests a low ratio of effective population size: census population size for Cx. quinquefasciatus, perhaps coupled with strong geographically-restricted population structure. Spatial definition of populations will be an important step for success of an expanded vector control program. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Urban lymphatic filariasis in the metropolis of Dar es Salaam, Tanzania

PubMed Central

2013-01-01

Background The last decades have seen a considerable increase in urbanization in Sub-Saharan Africa, and it is estimated that over 50% of the population will live in urban areas by 2040. Rapid growth of cities combined with limited economic resources often result in informal settlements and slums with favorable conditions for proliferation of vectors of lymphatic filariasis (LF). In Dar es Salaam, which has grown more than 30 times in population during the past 55 years (4.4 million inhabitants in 2012), previous surveys have indicated high prevalences of LF. This study investigated epidemiological aspects of LF in Dar es Salaam, as a background for planning and implementation of control. Methods Six sites with varying distance from the city center (3–30 km) and covering different population densities, socioeconomic characteristics, and water, sewerage and sanitary facilities were selected for the study. Pupils from one public primary school at each site were screened for circulating filarial antigen (CFA; marker of adult worm infection) and antibodies to Bm14 (marker of exposure to transmission). Community members were examined for CFA, microfilariae and chronic manifestations. Structured questionnaires were administered to pupils and heads of community households, and vector surveys were carried out in selected households. Results The study indicated that a tremendous decrease in the burden of LF infection had occurred, despite haphazard urbanisation. Contributing factors may be urban malaria control targeting Anopheles vectors, short survival time of the numerous Culex quinquefasciatus vectors in the urban environment, widespread use of bed nets and other mosquito proofing measures, and mass drug administration (MDA) in 2006 and 2007. Although the level of ongoing transmission was low, the burden of chronic LF disease was still high. Conclusions The development has so far been promising, but continued efforts are necessary to ensure elimination of LF as a

Causal chain mapping: a novel method to analyse treatment compliance decisions relating to lymphatic filariasis elimination in Alor, Indonesia.

PubMed

Krentel, Alison; Aunger, Robert

2012-08-01

Many public health programmes require individuals to comply with particular behaviours that are novel to them, for example, acquiring new eating habits, accepting immunizations or taking a new medication. In particular, mass drug administration programmes only work to reduce the prevalence of a disease if significant proportions of the target population take the drug in question. In such cases, knowledge of the factors most likely to lead to high levels of compliance is crucial to the programme's success. Existing models of compliance tend to either address interpersonal, organizational or psychological causes independently. Here, the authors present a formal method for analysing relevant factors in the situational context of the compliant behaviour, identifying how these factors may interact within the individual. This method was developed from semantic network analysis, augmented to include environmental and demographic variables to show causal linkages-hence the name 'causal chain mapping'. The ability of this method to provide significant insight into the actual behaviour of individuals is demonstrated with examples from a mass drug administration for lymphatic filariasis in Alor District, Indonesia. The use of this method is likely to help identify key components influencing compliance, and thus make any public health programme reliant on the adoption of novel behaviours more effective.

Are Alternative Strategies Required to Accelerate the Global Elimination of Lymphatic Filariasis? Insights From Mathematical Models

PubMed Central

Stolk, Wilma A; Prada, Joaquin M; Smith, Morgan E; Kontoroupis, Periklis; de Vos, Anneke S; Touloupou, Panayiota; Irvine, Michael A; Brown, Paul; Subramanian, Swaminathan; Kloek, Marielle; Michael, E; Hollingsworth, T Deirdre; de Vlas, Sake J

2018-01-01

Abstract Background With the 2020 target year for elimination of lymphatic filariasis (LF) approaching, there is an urgent need to assess how long mass drug administration (MDA) programs with annual ivermectin + albendazole (IA) or diethylcarbamazine + albendazole (DA) would still have to be continued, and how elimination can be accelerated. We addressed this using mathematical modeling. Methods We used 3 structurally different mathematical models for LF transmission (EPIFIL, LYMFASIM, TRANSFIL) to simulate trends in microfilariae (mf) prevalence for a range of endemic settings, both for the current annual MDA strategy and alternative strategies, assessing the required duration to bring mf prevalence below the critical threshold of 1%. Results Three annual MDA rounds with IA or DA and good coverage (≥65%) are sufficient to reach the threshold in settings that are currently at mf prevalence <4%, but the required duration increases with increasing mf prevalence. Switching to biannual MDA or employing triple-drug therapy (ivermectin, diethylcarbamazine, and albendazole [IDA]) could reduce program duration by about one-third. Optimization of coverage reduces the time to elimination and is particularly important for settings with a history of poorly implemented MDA (low coverage, high systematic noncompliance). Conclusions Modeling suggests that, in several settings, current annual MDA strategies will be insufficient to achieve the 2020 LF elimination targets, and programs could consider policy adjustment to accelerate, guided by recent monitoring and evaluation data. Biannual treatment and IDA hold promise in reducing program duration, provided that coverage is good, but their efficacy remains to be confirmed by more extensive field studies. PMID:29860286

Are Alternative Strategies Required to Accelerate the Global Elimination of Lymphatic Filariasis? Insights From Mathematical Models.

PubMed

Stolk, Wilma A; Prada, Joaquin M; Smith, Morgan E; Kontoroupis, Periklis; de Vos, Anneke S; Touloupou, Panayiota; Irvine, Michael A; Brown, Paul; Subramanian, Swaminathan; Kloek, Marielle; Michael, E; Hollingsworth, T Deirdre; de Vlas, Sake J

2018-06-01

With the 2020 target year for elimination of lymphatic filariasis (LF) approaching, there is an urgent need to assess how long mass drug administration (MDA) programs with annual ivermectin + albendazole (IA) or diethylcarbamazine + albendazole (DA) would still have to be continued, and how elimination can be accelerated. We addressed this using mathematical modeling. We used 3 structurally different mathematical models for LF transmission (EPIFIL, LYMFASIM, TRANSFIL) to simulate trends in microfilariae (mf) prevalence for a range of endemic settings, both for the current annual MDA strategy and alternative strategies, assessing the required duration to bring mf prevalence below the critical threshold of 1%. Three annual MDA rounds with IA or DA and good coverage (≥65%) are sufficient to reach the threshold in settings that are currently at mf prevalence <4%, but the required duration increases with increasing mf prevalence. Switching to biannual MDA or employing triple-drug therapy (ivermectin, diethylcarbamazine, and albendazole [IDA]) could reduce program duration by about one-third. Optimization of coverage reduces the time to elimination and is particularly important for settings with a history of poorly implemented MDA (low coverage, high systematic noncompliance). Modeling suggests that, in several settings, current annual MDA strategies will be insufficient to achieve the 2020 LF elimination targets, and programs could consider policy adjustment to accelerate, guided by recent monitoring and evaluation data. Biannual treatment and IDA hold promise in reducing program duration, provided that coverage is good, but their efficacy remains to be confirmed by more extensive field studies.

Factors Associated with the Performance and Cost-Effectiveness of Using Lymphatic Filariasis Transmission Assessment Surveys for Monitoring Soil-Transmitted Helminths: A Case Study in Kenya

PubMed Central

Smith, Jennifer L.; Sturrock, Hugh J. W.; Assefa, Liya; Nikolay, Birgit; Njenga, Sammy M.; Kihara, Jimmy; Mwandawiro, Charles S.; Brooker, Simon J.

2015-01-01

Transmission assessment surveys (TAS) for lymphatic filariasis have been proposed as a platform to assess the impact of mass drug administration (MDA) on soil-transmitted helminths (STHs). This study used computer simulation and field data from pre- and post-MDA settings across Kenya to evaluate the performance and cost-effectiveness of the TAS design for STH assessment compared with alternative survey designs. Variations in the TAS design and different sample sizes and diagnostic methods were also evaluated. The district-level TAS design correctly classified more districts compared with standard STH designs in pre-MDA settings. Aggregating districts into larger evaluation units in a TAS design decreased performance, whereas age group sampled and sample size had minimal impact. The low diagnostic sensitivity of Kato-Katz and mini-FLOTAC methods was found to increase misclassification. We recommend using a district-level TAS among children 8–10 years of age to assess STH but suggest that key consideration is given to evaluation unit size. PMID:25487730

Elimination of lymphatic filariasis as a public health problem from the Cook Islands.

PubMed

Ave, Charlie; Kapa, D Ramaiah; Ottesen, Eric

2018-01-01

The Cook Islands has a long history of high-endemicity lymphatic filariasis (LF) transmitted by Aedes vector mosquitoes. Though the infection prevalence had declined between 1975 and 1999 following episodic treatment activities, still infection was widespread with pockets of persistent infection. Beginning in 1999, the Cook Islands embarked on a national program, in partnership with Pacific Programme to Eliminate LF (PacELF), to eliminate LF as a public health problem. All 12 inhabited islands were identified as endemic, and six rounds of mass drug administration (MDA) with once-yearly, single-dose albendazole plus diethylcarbamazine (DEC) were implemented during 2000-2006 to interrupt transmission of LF. Surveys carried out at the baseline, mid-term, stop-MDA, and post-MDA periods assessed LF antigen (Ag) prevalence in children and adults. Historical data, health workers' observations, and hospital records were used to assess the trend and burden of chronic disease. The baseline Ag prevalence (1999) ranged from 2.0% in Manihiki to > 18.0% in Aitutaki, Mitiaro, and Pukapuka, and the national average Ag prevalence was 8.6%. MDA, carried out with a national treatment coverage over six annual rounds of MDA ranging from 63.5 to 96.7% in different years, was stopped in 2007. By then, the national Ag prevalence had declined to 0.27%. The post-MDA surveillance survey results (2013-2014) showed that Ag prevalence had fallen to 0% in 11/12 islands, and the national prevalence was only 0.03%. Chronic filarial disease had almost entirely disappeared. The Cook Islands met all the criteria required for the World Health Organization (WHO) to acknowledge elimination of LF as a public health problem, as it did officially in 2016. This success also confirms that LF, even when transmitted by Aedes mosquitoes that are recognized to be more efficient than other vector species, can be eliminated as a public health problem by six rounds of MDA.

Immune responses of B. malayi thioredoxin (TRX) and venom allergen homologue (VAH) chimeric multiple antigen for lymphatic filariasis.

PubMed

Anugraha, Gandhirajan; Jeyaprita, Parasurama Jawaharlal; Madhumathi, Jayaprakasam; Sheeba, Tamilvanan; Kaliraj, Perumal

2013-12-01

Although multiple vaccine strategy for lymphatic filariasis has provided tremendous hope, the choice of antigens used in combination has determined its success in the previous studies. Multiple antigens comprising key vaccine candidates from different life cycle stages would provide a promising strategy if the antigenic combination is chosen by careful screening. In order to analyze one such combination, we have used a chimeric construct carrying the well studied B. malayi antigens thioredoxin (BmTRX) and venom allergen homologue (BmVAH) as a fusion protein (TV) and evaluated its immune responses in mice model. The efficacy of fusion protein vaccine was explored in comparison with the single antigen vaccines and their cocktail. In mice, TV induced significantly high antibody titer of 1,28,000 compared to cocktail vaccine TRX+VAH (50,000) and single antigen vaccine TRX (16,000) or VAH (50,000). Furthermore, TV elicited higher level of cellular proliferative response together with elevated levels of IFN-γ, IL-4 and IL-5 indicating a Th1/Th2 balanced response. The isotype antibody profile showed significantly high level of IgG1 and IgG2b confirming the balanced response elicited by TV. Immunization with TV antigen induced high levels of both humoral and cellular immune responses compared to either cocktail or antigen given alone. The result suggests that TV is highly immunogenic in mice and hence the combination needs to be evaluated for its prophylactic potential.

Traditional herbal remedies and dietary spices from Cameroon as novel sources of larvicides against filariasis mosquitoes?

PubMed

Pavela, Roman; Maggi, Filippo; Mbuntcha, Hélène; Woguem, Verlaine; Fogang, Hervet Paulin Dongmo; Womeni, Hilaire Macaire; Tapondjou, Léon Azefack; Barboni, Luciano; Nicoletti, Marcello; Canale, Angelo; Benelli, Giovanni

2016-12-01

In Cameroon, many dietary spices are used by traditional healers to cure several diseases such as cancer and microbial infections. Aframomum daniellii, Dichrostachys cinerea and Echinops giganteus are Cameroonian spices widely used as flavourings and as food additives. Moreover, they are traditionally herbal remedies employed to treat several diseases, as well as to control populations of insect pests. In this research, we analysed the chemical composition of A. daniellii, D. cinerea and E. giganteus essential oils and we evaluated their larvicidal potential against larvae of the filariasis and West Nile virus vector Culex quinquefasciatus. The essential oils were obtained from different plant parts by hydrodistillation and their composition was analysed by GC-MS. The three spices exhibited different volatile chemical profiles, being characterized by 1,8-cineole, sabinene and β-pinene (A. daniellii), geraniol and terpinen-4-ol (D. cinerea), and silphiperfol-6-ene and presilphiperfolan-8-ol (E. giganteus). Results showed that the highest larvicidal toxicity on Cx. quinquefasciatus was exerted by D. cinerea essential oil (LC 50  = 39.1 μL L -1 ), followed by A. daniellii (pericarp essential oil: LC 50  = 65.5 μL L -1 ; leaves: LC 50  = 65.5μL L -1 ; seeds: LC 50  = 106.5μL L -1 ) and E. giganteus (LC 50  = 227.4 μL L -1 ). Overall, the chance to use the D. cinerea essential oil against Cx. quinquefasciatus young instars seems promising, since it is effective at moderate doses and could be an advantageous alternative to build newer mosquito control tools.

Modeling the Impact and Costs of Semiannual Mass Drug Administration for Accelerated Elimination of Lymphatic Filariasis

PubMed Central

de Vlas, Sake J.; Fischer, Peter U.; Weil, Gary J.; Goldman, Ann S.

2013-01-01

The Global Program to Eliminate Lymphatic Filariasis (LF) has a target date of 2020. This program is progressing well in many countries. However, progress has been slow in some countries, and others have not yet started their mass drug administration (MDA) programs. Acceleration is needed. We studied how increasing MDA frequency from once to twice per year would affect program duration and costs by using computer simulation modeling and cost projections. We used the LYMFASIM simulation model to estimate how many annual or semiannual MDA rounds would be required to eliminate LF for Indian and West African scenarios with varied pre-control endemicity and coverage levels. Results were used to estimate total program costs assuming a target population of 100,000 eligibles, a 3% discount rate, and not counting the costs of donated drugs. A sensitivity analysis was done to investigate the robustness of these results with varied assumptions for key parameters. Model predictions suggested that semiannual MDA will require the same number of MDA rounds to achieve LF elimination as annual MDA in most scenarios. Thus semiannual MDA programs should achieve this goal in half of the time required for annual programs. Due to efficiency gains, total program costs for semiannual MDA programs are projected to be lower than those for annual MDA programs in most scenarios. A sensitivity analysis showed that this conclusion is robust. Semiannual MDA is likely to shorten the time and lower the cost required for LF elimination in countries where it can be implemented. This strategy may improve prospects for global elimination of LF by the target year 2020. PMID:23301115

Effect of water resource development and management on lymphatic filariasis, and estimates of populations at risk.

PubMed

Erlanger, Tobias E; Keiser, Jennifer; Caldas De Castro, Marcia; Bos, Robert; Singer, Burton H; Tanner, Marcel; Utzinger, Jürg

2005-09-01

Lymphatic filariasis (LF) is a debilitating disease overwhelmingly caused by Wuchereria bancrofti, which is transmitted by various mosquito species. Here, we present a systematic literature review with the following objectives: (i) to establish global and regional estimates of populations at risk of LF with particular consideration of water resource development projects, and (ii) to assess the effects of water resource development and management on the frequency and transmission dynamics of the disease. We estimate that globally, 2 billion people are at risk of LF. Among them, there are 394.5 million urban dwellers without access to improved sanitation and 213 million rural dwellers living in close proximity to irrigation. Environmental changes due to water resource development and management consistently led to a shift in vector species composition and generally to a strong proliferation of vector populations. For example, in World Health Organization (WHO) subregions 1 and 2, mosquito densities of the Anopheles gambiae complex and Anopheles funestus were up to 25-fold higher in irrigated areas when compared with irrigation-free sites. Although the infection prevalence of LF often increased after the implementation of a water project, there was no clear association with clinical symptoms. Concluding, there is a need to assess and quantify changes of LF transmission parameters and clinical manifestations over the entire course of water resource developments. Where resources allow, integrated vector management should complement mass drug administration, and broad-based monitoring and surveillance of the disease should become an integral part of large-scale waste management and sanitation programs, whose basic rationale lies in a systemic approach to city, district, and regional level health services and disease prevention.

A case study of risk factors for lymphatic filariasis in the Republic of Congo.

PubMed

Chesnais, Cédric B; Missamou, François; Pion, Sébastien D; Bopda, Jean; Louya, Frédéric; Majewski, Andrew C; Fischer, Peter U; Weil, Gary J; Boussinesq, Michel

2014-07-01

Little is known regarding risk factors for lymphatic filariasis (LF) in Central Africa. We studied the epidemiology of LF in an endemic village in the Republic of Congo. Dependent variables were Wuchereria bancrofti antigenemia (ICT card test) and microfilaremia (night blood smears). The following factors were investigated: sex, age, bed net, latrines, source of water, uptake of anthelmintic drugs, hunting/fishing activities, and occasionally sleeping in the bush. Mixed multivariate logistic regression models were used. 134 of 774 subjects aged ≥ 5 years (17.3%) had W. bancrofti antigenemia and 41 (5.3%) had microfilaremia (mf). Infection rates increased with age up to roughly 20 years and remained stable thereafter. Multivariate analysis of antigenemia demonstrated an increased risk for males (OR = 2.0 [1.3-3.0]) and for people who hunt or fish (OR = 1.5 [1.0-2.4]) and a protective effect of latrines (OR = 0.5 [0.4-0.8]). Among males, those hunting or fishing at night had an increased risk for antigenemia (OR = 1.9 [1.1-3.5]), and use of latrines was protective (OR = 0.5 [0.3-0.9]). For females, bed nets were protective (OR = 0.4 [0.1-0.9]), and there was a strong household effect (intraclass correlation coefficient [ICC]: 0.24). When mf was used as the dependent variable, males had a higher risk for infection (OR = 5.4 [2.1-13.4]), latrines had a protective effect (OR = 0.4 [0.1-0.9]) and there was a marked household effect (ICC = 0.49). Age, sex, and occupation-dependent exposure to mosquitoes were important risk factors for infection with W. bancrofti in this study. It is likely that men often acquire infection in high transmission areas outside of the village, while children and women are infected in areas with lower transmission inside or near the village. Additional studies are needed to determine whether these findings apply to other areas in Central Africa.

Role of fine needle aspiration cytology in diagnosing filarial arm cysts.

PubMed

Tandon, Nishi; Bansal, Cherry; Sharma, Richa; Irfan, Sumaiya

2013-05-17

Filariasis is prevalent in tropical and subtropical areas and is endemic in regions of India. Lymphatic filariasis in India is caused mainly by two species of nematodes: Wuchereria bancrofti and Brugia malayi, which invade the human lymphatic system. We report two cases of superficial cystic lesions of the upper limb revealed on fine needle aspiration (FNA) to be clinically unsuspected filariasis. Despite similar aetiologies, both cases revealed variations in aspirate nature, smear morphology and peripheral blood findings. FNA provides definitive diagnosis and is an important tool for diagnosing soft tissue swellings owing to filariasis.

How much will it cost to eradicate lymphatic filariasis? An analysis of the financial and economic costs of intensified efforts against lymphatic filariasis

PubMed Central

Kastner, Randee J.; Sicuri, Elisa; Stone, Christopher M.; Matwale, Gabriel; Onapa, Ambrose; Tediosi, Fabrizio

2017-01-01

Introduction Lymphatic filariasis (LF), a neglected tropical disease (NTD) preventable through mass drug administration (MDA), is one of six diseases deemed possibly eradicable. Previously we developed one LF elimination scenario, which assumes MDA scale-up to continue in all countries that have previously undertaken MDA. In contrast, our three previously developed eradication scenarios assume all LF endemic countries will undertake MDA at an average (eradication I), fast (eradication II), or instantaneous (eradication III) rate of scale-up. In this analysis we use a micro-costing model to project the financial and economic costs of each of these scenarios in order to provide evidence to decision makers about the investment required to eliminate and eradicate LF. Methodology/Key findings Costing was undertaken from a health system perspective, with all results expressed in 2012 US dollars (USD). A discount rate of 3% was applied to calculate the net present value of future costs. Prospective NTD budgets from LF endemic countries were reviewed to preliminarily determine activities and resources necessary to undertake a program to eliminate LF at a country level. In consultation with LF program experts, activities and resources were further reviewed and a refined list of activities and necessary resources, along with their associated quantities and costs, were determined and grouped into the following activities: advocacy and communication, capacity strengthening, coordination and strengthening partnerships, data management, ongoing surveillance, monitoring and supervision, drug delivery, and administration. The costs of mapping and undertaking transmission assessment surveys and the value of donated drugs and volunteer time were also accounted for. Using previously developed scenarios and deterministic estimates of MDA duration, the financial and economic costs of interrupting LF transmission under varying rates of MDA scale-up were then modelled using a micro

How much will it cost to eradicate lymphatic filariasis? An analysis of the financial and economic costs of intensified efforts against lymphatic filariasis.

PubMed

Kastner, Randee J; Sicuri, Elisa; Stone, Christopher M; Matwale, Gabriel; Onapa, Ambrose; Tediosi, Fabrizio

2017-09-01

Lymphatic filariasis (LF), a neglected tropical disease (NTD) preventable through mass drug administration (MDA), is one of six diseases deemed possibly eradicable. Previously we developed one LF elimination scenario, which assumes MDA scale-up to continue in all countries that have previously undertaken MDA. In contrast, our three previously developed eradication scenarios assume all LF endemic countries will undertake MDA at an average (eradication I), fast (eradication II), or instantaneous (eradication III) rate of scale-up. In this analysis we use a micro-costing model to project the financial and economic costs of each of these scenarios in order to provide evidence to decision makers about the investment required to eliminate and eradicate LF. Costing was undertaken from a health system perspective, with all results expressed in 2012 US dollars (USD). A discount rate of 3% was applied to calculate the net present value of future costs. Prospective NTD budgets from LF endemic countries were reviewed to preliminarily determine activities and resources necessary to undertake a program to eliminate LF at a country level. In consultation with LF program experts, activities and resources were further reviewed and a refined list of activities and necessary resources, along with their associated quantities and costs, were determined and grouped into the following activities: advocacy and communication, capacity strengthening, coordination and strengthening partnerships, data management, ongoing surveillance, monitoring and supervision, drug delivery, and administration. The costs of mapping and undertaking transmission assessment surveys and the value of donated drugs and volunteer time were also accounted for. Using previously developed scenarios and deterministic estimates of MDA duration, the financial and economic costs of interrupting LF transmission under varying rates of MDA scale-up were then modelled using a micro-costing approach. The elimination scenario

Twelve-month longitudinal parasitological assessment of lymphatic filariasis-positive individuals: impact of a biannual treatment with ivermectin and albendazole.

PubMed

Kanamitie, John N; Ahorlu, Collins S; Otchere, Joseph; Aboagye-Antwi, Fred; Kwansa-Bentum, Bethel; Boakye, Daniel A; Biritwum, Nana-Kwadwo; Wilson, Michael D; de Souza, Dziedzom K

2017-11-01

Mass drug administration (MDA) for the control of lymphatic filariasis (LF), in Ghana, started in the year 2000. While this had great success in many implementation units, there remain areas with persistent transmission, after more than 10 years of treatment. A closer examination of the parasite populations could help understand the reasons for persistent infections and formulate appropriate strategies to control LF in these areas of persistent transmission. In a longitudinal study, we assessed the prevalence of microfilaraemia (mf) in two communities with 12 years of MDA in Ghana. In baseline surveys 6 months after the National MDA in 2014, 370 consenting individuals were tested for antigenaemia using immunochromatographic test (ICT) cards and had their mf count determined through night blood surveys. 48 ICT positives, of whom, 17 were positive for mf, were treated with 400 μg/kg ivermectin + 400 mg albendazole and subsequently followed for parasitological assessment at 3-month intervals for 1 year. This overlapped with the National MDA in 2015. There was a 68% parasite clearance 3 months after treatment. The pre-treatment mf count differed significantly from the post-treatment mf counts at 3 months (P = 0.0023), 6 months (P = 0.0051), 9 months (P = 0.0113) and 12 months (P = 0.0008). In these settings with persistent LF transmission, twice-yearly treatment may help accelerate LF elimination. Further large-scale evaluations are required to ascertain these findings. © 2017 John Wiley & Sons Ltd.

[Analysis of scientific information published in Brazil in 5 years on Chagas disease, schistosomiasis, malaria, leishmaniasis and filariasis].

PubMed

Costa Lima, J A; Schmitt Rosa, C M; Piegas, M H; Peixinho, A; Schmidt, A; Briquet de Lemos, A A; Marcilio de Souza, C A

1985-01-01

This paper offers a quantitative evaluation of the scientific information produced in Brazil on several endemic diseases: Chagas' disease, schistosomiasis, leishmaniasis, leprosy, malaria and filariasis. The source of data was the Index Medicus Latino Americano (IMLA), and the published scientific information was analyzed in general and specifically, by type of disease and year of publication. The indexed production of articles on the material of the Latin American countries as a whole increased from 3,506 articles in 1978 to 5,528 in 1982 (for an increase of 52.7%), whereas that of Brazil alone rose from 1,781 to 2,531 (an increase of 42.1%) during the same period. The output of articles on endemic diseases totaled 703 papers (6.3% of the total indexed production). Of this total, 441 (62.7%) was on applied research and 262 (37.3%) were on basic research, and these proportions held relatively constant. Chagas' disease and schistosomiasis accounted for 75.2% of that total over the period considered. The production of papers on the diseases of interest grew 79.2%, at the same rate as that of all biomedical information published in Brazil over the period. An equilibrium was reached between the numbers of basic and applied papers. The analysis also identified the core of Brazilian periodicals that most frequently publish information on those endemics. It was also found that a large proportion of articles by Brazilian authors are published in journals of international circulation, and the foreign journals that publish papers by researchers in Brazil were identified.

Lymphatic filariasis among children and adolescents: spatial identification via socio-environmental indicators to define priority areas for elimination.

PubMed

Brandão, Eduardo; Bonfim, Cristine; Alves, Ayla; Oliveira, Conceição; Montenegro, Carlos Eduardo; Costa, Tadeu; Maciel, Amélia; Medeiros, Zulma

2015-09-01

The occurrence of lymphatic filariasis (LF) and its transmission dynamics among children and adolescents are still not clearly elucidated. The aim of this study was to describe the spatial distribution of microfilaremia and its relationship with socio-environmental variables, thereby identifying areas at greater risk of transmission. An ecological study was conducted, in which the analysis unit was formed by districts of the municipality of Jaboatão dos Guararapes in the state of Pernambuco, Brazil. The data source was a parasitological survey. Inadequate sewage disposal, number of people in the household and income of between 0.5 and 1 minimum salary were used to construct the socio-environmental indicator. The districts were then grouped according to the indicator into three risk strata, using the k-means clustering technique. In the study, 96/8670 (1.1%) of the population were found to present microfilaremia. The high-risk stratum had a mean prevalence rate of 1.9% and a risk of 2.56 (p<0.05), in relation to the low-risk stratum. The middle stratum grouped the households that presented an intermediate risk of transmission, with a prevalence rate of 1.92%. The indicator used is a promising tool that enables the precise measurement of the relationship between social deprivation and the prevalence of filarial infection among children. Thus, it can be used to plan control and elimination actions. © The Author 2015. 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.

Towards elimination of lymphatic filariasis: social mobilization issues and challenges in mass drug administration with anti-filarial drugs in Tamil Nadu, South India.

PubMed

Nandha, B; Krishnamoorthy, K; Jambulingam, P

2013-08-01

India is a signatory to World Health Assembly resolution for elimination of lymphatic filariasis (LF) and National Health Policy has set the goal of LF elimination by 2015. Annual mass drug administration (MDA) is ongoing in endemic districts since 1996-97. Compliance rate is a crucial factor in achieving elimination and was assessed in three districts of Tamil Nadu for 10th and 11th treatment rounds (TRs). An in-depth study assessed the impact of social mobilization by drug distributors (DDs) in two areas from each of the three districts. Overall coverage and compliance for assessed TRs were 76.3 and 67.7% which is below the optimum level to achieve LF elimination. Modifiable determinants continue to be the reason for non-consumption even in the 11th TR and 20.8% were systematic non-compliers. In 76.4% of the cases, DDs failed to adhere to three mandatory visits as per the guidelines. Number of visits by DDs in relation to low and high MDA coverage areas showed a significant relationship (P ≤ 0.000). MDA is limited to drug distribution alone and efforts by DDs in preparing the community were inadequate. Probable means to meet the challenges in preparation of the community is discussed.

A case study of risk factors for lymphatic filariasis in the Republic of Congo

PubMed Central

2014-01-01

Background Little is known regarding risk factors for lymphatic filariasis (LF) in Central Africa. We studied the epidemiology of LF in an endemic village in the Republic of Congo. Methods Dependent variables were Wuchereria bancrofti antigenemia (ICT card test) and microfilaremia (night blood smears). The following factors were investigated: sex, age, bed net, latrines, source of water, uptake of anthelmintic drugs, hunting/fishing activities, and occasionally sleeping in the bush. Mixed multivariate logistic regression models were used. Results 134 of 774 subjects aged ≥ 5 years (17.3%) had W. bancrofti antigenemia and 41 (5.3%) had microfilaremia (mf). Infection rates increased with age up to roughly 20 years and remained stable thereafter. Multivariate analysis of antigenemia demonstrated an increased risk for males (OR = 2.0 [1.3-3.0]) and for people who hunt or fish (OR = 1.5 [1.0-2.4]) and a protective effect of latrines (OR = 0.5 [0.4-0.8]). Among males, those hunting or fishing at night had an increased risk for antigenemia (OR = 1.9 [1.1-3.5]), and use of latrines was protective (OR = 0.5 [0.3-0.9]). For females, bed nets were protective (OR = 0.4 [0.1-0.9]), and there was a strong household effect (intraclass correlation coefficient [ICC]: 0.24). When mf was used as the dependent variable, males had a higher risk for infection (OR = 5.4 [2.1-13.4]), latrines had a protective effect (OR = 0.4 [0.1-0.9]) and there was a marked household effect (ICC = 0.49). Conclusions Age, sex, and occupation-dependent exposure to mosquitoes were important risk factors for infection with W. bancrofti in this study. It is likely that men often acquire infection in high transmission areas outside of the village, while children and women are infected in areas with lower transmission inside or near the village. Additional studies are needed to determine whether these findings apply to other areas in Central Africa. PMID:24984769

Bancroftian filariasis in Maceio, state of Alagoas, Brazil: Observations on Culex quinquefasciatus after blood feeding on individuals with different densities of microfilariae in the peripheral blood stream.

PubMed

Brito, A C; Fontes, G; Williams, P; Rocha, E M

1998-04-01

Females of laboratory-reared Culex quinquefasciatus were allowed to take blood meals on individuals with low (1-100 microfilariae/ml of peripheral blood), moderate (101-500 microfilariae/ml), and high (> 500 microfilariae/ml) microfilaremia. The mosquitoes ingested 1.39-3.80 microl of blood and infective third-stage (L3) larvae were first recorded 13-14 days after the infecting blood meal. The number of microfilariae ingested by mosquitoes was proportional to the density of microfilariae in the peripheral blood of the human subjects, but with a concentration factor of up to 6.5 times the expected number. Survival of mosquitoes was not influenced by the density of microfilariae in the peripheral blood of infected individuals. Infectivity indices were proportional to microfilaremia in human subjects. The number of L3 larvae/female (intensity of infection) was not influenced by individual microfilaremia. The highest vector efficiency and the best experimental infection index were recorded in mosquitoes that blood fed on individuals with moderate microfilaremia. The results are discussed in relation to the transmission on Bancroftian filariasis in the study area.

Impact of six rounds of mass drug administration on Brugian filariasis and soil-transmitted helminth infections in eastern Indonesia.

PubMed

Supali, Taniawati; Djuardi, Yenny; Bradley, Mark; Noordin, Rahmah; Rückert, Paul; Fischer, Peter U

2013-01-01

The lymphatic filarial parasite Brugia timori occurs only in eastern Indonesia where it causes high morbidity. The absence of an animal reservoir, the inefficient transmission by Anopheles mosquitoes and the high sensitivity to DEC/albendazole treatment make this species a prime candidate for elimination by mass drug administration (MDA). We evaluated the effect of MDA using DEC and albendazole on B. timori and soil transmitted helminths (STH) in a cross-sectional study of a sentinel village on Alor Island annually over a period of 10 years. Pre-MDA the microfilaria (MF) prevalence was 26% and 80% of the residents had filaria-specific IgG4 antibodies. In 2010, 34 months after the 6(th) round of MDA, MF and antibody rates were only 0.17% and 6.4%, respectively. The MDA campaign had also a beneficial effect on STH. Baseline prevalence rates for Ascaris, hookworm and Trichuris were 34%, 28%, and 11%, respectively; these rates were reduced to 27%, 4%, and 2% one year after the 5(th) round of MDA. Unfortunately, STH rates rebounded 34 months after cessation of MDA and approached pre-MDA rates. However, the intensity of STH infection in 2009 was still reduced, and no heavy infections were detected. MDA with DEC/albendazole has had a major impact on B. timori MF and IgG4 antibody rates, providing a proof of principle that elimination is feasible. We also documented the value of annual DEC/albendazole as a mass de-worming intervention and the importance of continuing some form of STH control after cessation of MDA for filariasis.

A Review of Factors That Influence Individual Compliance with Mass Drug Administration for Elimination of Lymphatic Filariasis

PubMed Central

Krentel, Alison; Fischer, Peter U.; Weil, Gary J.

2013-01-01

Background The success of programs to eliminate lymphatic filariasis (LF) depends in large part on their ability to achieve and sustain high levels of compliance with mass drug administration (MDA). This paper reports results from a comprehensive review of factors that affect compliance with MDA. Methodology/Principal Findings Papers published between 2000 and 2012 were considered, and 79 publications were included in the final dataset for analysis after two rounds of selection. While results varied in different settings, some common features were associated with successful programs and with compliance by individuals. Training and motivation of drug distributors is critically important, because these people directly interact with target populations, and their actions can affect MDA compliance decisions by families and individuals. Other important programmatic issues include thorough preparation of personnel, supplies, and logistics for implementation and preparation of the population for MDA. Demographic factors (age, sex, income level, and area of residence) are often associated with compliance by individuals, but compliance decisions are also affected by perceptions of the potential benefits of participation versus the risk of adverse events. Trust and information can sometimes offset fear of the unknown. While no single formula can ensure success MDA in all settings, five key ingredients were identified: engender trust, tailor programs to local conditions, take actions to minimize the impact of adverse events, promote the broader benefits of the MDA program, and directly address the issue of systematic non-compliance, which harms communities by prolonging their exposure to LF. Conclusions/Significance This review has identified factors that promote coverage and compliance with MDA for LF elimination across countries. This information may be helpful for explaining results that do not meet expectations and for developing remedies for ailing MDA programs. Our

Laboratory and Field Evaluation of a New Rapid Test for Detecting Wuchereria bancrofti Antigen in Human Blood

PubMed Central

Weil, Gary J.; Curtis, Kurt C.; Fakoli, Lawrence; Fischer, Kerstin; Gankpala, Lincoln; Lammie, Patrick J.; Majewski, Andrew C.; Pelletreau, Sonia; Won, Kimberly Y.; Bolay, Fatorma K.; Fischer, Peter U.

2013-01-01

Global Program to Eliminate Lymphatic Filariasis (GPELF) guidelines call for using filarial antigen testing to identify endemic areas that require mass drug administration (MDA) and for post-MDA surveillance. We compared a new filarial antigen test (the Alere Filariasis Test Strip) with the reference BinaxNOW Filariasis card test that has been used by the GPELF for more than 10 years. Laboratory testing of 227 archived serum or plasma samples showed that the two tests had similar high rates of sensitivity and specificity and > 99% agreement. However, the test strip detected 26.5% more people with filarial antigenemia (124/503 versus 98/503) and had better test result stability than the card test in a field study conducted in a filariasis-endemic area in Liberia. Based on its increased sensitivity and other practical advantages, we believe that the test strip represents a major step forward that will be welcomed by the GPELF and the filariasis research community. PMID:23690552

Transmission Assessment Surveys (TAS) to Define Endpoints for Lymphatic Filariasis Mass Drug Administration: A Multicenter Evaluation

PubMed Central

Chu, Brian K.; Deming, Michael; Biritwum, Nana-Kwadwo; Bougma, Windtaré R.; Dorkenoo, Améyo M.; El-Setouhy, Maged; Fischer, Peter U.; Gass, Katherine; Gonzalez de Peña, Manuel; Mercado-Hernandez, Leda; Kyelem, Dominique; Lammie, Patrick J.; Flueckiger, Rebecca M.; Mwingira, Upendo J.; Noordin, Rahmah; Offei Owusu, Irene; Ottesen, Eric A.; Pavluck, Alexandre; Pilotte, Nils; Rao, Ramakrishna U.; Samarasekera, Dilhani; Schmaedick, Mark A.; Settinayake, Sunil; Simonsen, Paul E.; Supali, Taniawati; Taleo, Fasihah; Torres, Melissa; Weil, Gary J.; Won, Kimberly Y.

2013-01-01

Background Lymphatic filariasis (LF) is targeted for global elimination through treatment of entire at-risk populations with repeated annual mass drug administration (MDA). Essential for program success is defining and confirming the appropriate endpoint for MDA when transmission is presumed to have reached a level low enough that it cannot be sustained even in the absence of drug intervention. Guidelines advanced by WHO call for a transmission assessment survey (TAS) to determine if MDA can be stopped within an LF evaluation unit (EU) after at least five effective rounds of annual treatment. To test the value and practicality of these guidelines, a multicenter operational research trial was undertaken in 11 countries covering various geographic and epidemiological settings. Methodology The TAS was conducted twice in each EU with TAS-1 and TAS-2 approximately 24 months apart. Lot quality assurance sampling (LQAS) formed the basis of the TAS survey design but specific EU characteristics defined the survey site (school or community), eligible population (6–7 year olds or 1st–2nd graders), survey type (systematic or cluster-sampling), target sample size, and critical cutoff (a statistically powered threshold below which transmission is expected to be no longer sustainable). The primary diagnostic tools were the immunochromatographic (ICT) test for W. bancrofti EUs and the BmR1 test (Brugia Rapid or PanLF) for Brugia spp. EUs. Principal Findings/Conclusions In 10 of 11 EUs, the number of TAS-1 positive cases was below the critical cutoff, indicating that MDA could be stopped. The same results were found in the follow-up TAS-2, therefore, confirming the previous decision outcome. Sample sizes were highly sex and age-representative and closely matched the target value after factoring in estimates of non-participation. The TAS was determined to be a practical and effective evaluation tool for stopping MDA although its validity for longer-term post-MDA surveillance

Transmission assessment surveys (TAS) to define endpoints for lymphatic filariasis mass drug administration: a multicenter evaluation.

PubMed

Chu, Brian K; Deming, Michael; Biritwum, Nana-Kwadwo; Bougma, Windtaré R; Dorkenoo, Améyo M; El-Setouhy, Maged; Fischer, Peter U; Gass, Katherine; Gonzalez de Peña, Manuel; Mercado-Hernandez, Leda; Kyelem, Dominique; Lammie, Patrick J; Flueckiger, Rebecca M; Mwingira, Upendo J; Noordin, Rahmah; Offei Owusu, Irene; Ottesen, Eric A; Pavluck, Alexandre; Pilotte, Nils; Rao, Ramakrishna U; Samarasekera, Dilhani; Schmaedick, Mark A; Settinayake, Sunil; Simonsen, Paul E; Supali, Taniawati; Taleo, Fasihah; Torres, Melissa; Weil, Gary J; Won, Kimberly Y

2013-01-01

Lymphatic filariasis (LF) is targeted for global elimination through treatment of entire at-risk populations with repeated annual mass drug administration (MDA). Essential for program success is defining and confirming the appropriate endpoint for MDA when transmission is presumed to have reached a level low enough that it cannot be sustained even in the absence of drug intervention. Guidelines advanced by WHO call for a transmission assessment survey (TAS) to determine if MDA can be stopped within an LF evaluation unit (EU) after at least five effective rounds of annual treatment. To test the value and practicality of these guidelines, a multicenter operational research trial was undertaken in 11 countries covering various geographic and epidemiological settings. The TAS was conducted twice in each EU with TAS-1 and TAS-2 approximately 24 months apart. Lot quality assurance sampling (LQAS) formed the basis of the TAS survey design but specific EU characteristics defined the survey site (school or community), eligible population (6-7 year olds or 1(st)-2(nd) graders), survey type (systematic or cluster-sampling), target sample size, and critical cutoff (a statistically powered threshold below which transmission is expected to be no longer sustainable). The primary diagnostic tools were the immunochromatographic (ICT) test for W. bancrofti EUs and the BmR1 test (Brugia Rapid or PanLF) for Brugia spp. EUs. In 10 of 11 EUs, the number of TAS-1 positive cases was below the critical cutoff, indicating that MDA could be stopped. The same results were found in the follow-up TAS-2, therefore, confirming the previous decision outcome. Sample sizes were highly sex and age-representative and closely matched the target value after factoring in estimates of non-participation. The TAS was determined to be a practical and effective evaluation tool for stopping MDA although its validity for longer-term post-MDA surveillance requires further investigation.

Impact of Six Rounds of Mass Drug Administration on Brugian Filariasis and Soil-Transmitted Helminth Infections in Eastern Indonesia

PubMed Central

Supali, Taniawati; Djuardi, Yenny; Bradley, Mark; Noordin, Rahmah; Rückert, Paul; Fischer, Peter U.

2013-01-01

Background The lymphatic filarial parasite Brugia timori occurs only in eastern Indonesia where it causes high morbidity. The absence of an animal reservoir, the inefficient transmission by Anopheles mosquitoes and the high sensitivity to DEC/albendazole treatment make this species a prime candidate for elimination by mass drug administration (MDA). Methodology/Principal Findings We evaluated the effect of MDA using DEC and albendazole on B. timori and soil transmitted helminths (STH) in a cross-sectional study of a sentinel village on Alor Island annually over a period of 10 years. Pre-MDA the microfilaria (MF) prevalence was 26% and 80% of the residents had filaria-specific IgG4 antibodies. In 2010, 34 months after the 6th round of MDA, MF and antibody rates were only 0.17% and 6.4%, respectively. The MDA campaign had also a beneficial effect on STH. Baseline prevalence rates for Ascaris, hookworm and Trichuris were 34%, 28%, and 11%, respectively; these rates were reduced to 27%, 4%, and 2% one year after the 5th round of MDA. Unfortunately, STH rates rebounded 34 months after cessation of MDA and approached pre-MDA rates. However, the intensity of STH infection in 2009 was still reduced, and no heavy infections were detected. Conclusions/Significance MDA with DEC/albendazole has had a major impact on B. timori MF and IgG4 antibody rates, providing a proof of principle that elimination is feasible. We also documented the value of annual DEC/albendazole as a mass de-worming intervention and the importance of continuing some form of STH control after cessation of MDA for filariasis. PMID:24349595

The health and economic benefits of the global programme to eliminate lymphatic filariasis (2000-2014).

PubMed

Turner, Hugo C; Bettis, Alison A; Chu, Brian K; McFarland, Deborah A; Hooper, Pamela J; Ottesen, Eric A; Bradley, Mark H

2016-05-24

Lymphatic filariasis (LF), also known as elephantiasis, is a neglected tropical disease (NTD) targeted for elimination through a Global Programme to Eliminate LF (GPELF). Between 2000 and 2014, the GPELF has delivered 5.6 billion treatments to over 763 million people. Updating the estimated health and economic benefits of this significant achievement is important in justifying the resources and investment needed for eliminating LF. We combined previously established models to estimate the number of clinical manifestations and disability-adjusted life years (DALYs) averted from three benefit cohorts (those protected from acquiring infection, those with subclinical morbidity prevented from progressing and those with clinical disease alleviated). The economic savings associated with this disease prevention was then analysed in the context of prevented medical expenses incurred by LF clinical patients, potential income loss through lost-labour, and prevented costs to the health system to care for affected individuals. The indirect cost estimates were calculated using the human capital approach. A combination of four wage sources was used to estimate the fair market value of time for an agricultural worker with LF infection (to ensure a conservative estimate, the lowest wage value was used). We projected that due to the first 15 years of the GPELF 36 million clinical cases and 175 (116-250) million DALYs will potentially be averted. It was estimated that due to this notable health impact, US$100.5 billion will potentially be saved over the lifetimes of the benefit cohorts. This total amount results from summing the medical expenses incurred by LF patients (US$3 billion), potential income loss (US$94 billion), and costs to the health system (US$3.5 billion) that were projected to be prevented. The results were subjected to sensitivity analysis and were most sensitive to the assumed percentage of work hours lost for those suffering from chronic disease (changing the

Measurement of Circulating Filarial Antigen Levels in Human Blood with a Point-of-Care Test Strip and a Portable Spectrodensitometer

PubMed Central

Chesnais, Cédric B.; Vlaminck, Johnny; Kunyu-Shako, Billy; Pion, Sébastien D.; Awaca-Uvon, Naomi-Pitchouna; Weil, Gary J.; Mumba, Dieudonné; Boussinesq, Michel

2016-01-01

The Alere Filariasis Test Strip (FTS) is a qualitative, point-of-care diagnostic tool that detects Wuchereria bancrofti circulating filarial antigen (CFA) in human blood, serum, or plasma. The Global Program to Eliminate Lymphatic Filariasis employs the FTS for mapping filariasis-endemic areas and assessing the success of elimination efforts. The objective of this study was to explore the relationship between the intensity of positive test lines obtained by FTS with CFA levels as determined by enzyme-linked immunosorbent assay (ELISA) with blood and plasma samples from 188 individuals who live in a filariasis-endemic area. The intensity of the FTS test line was assessed visually to provide a semiquantitative score (visual Filariasis Test Strip [vFTS]), and line intensity was measured with a portable spectrodensitometer (quantitative Filariasis Test Strip [qFTS]). These results were compared with antigen levels measured by ELISA in plasma from the same subjects. qFTS measurements were highly correlated with vFTS scores (ρ = 0.94; P < 0.001) and with plasma CFA levels (ρ = 0.91; P < 0.001). Thus, qFTS assessment is a convenient method for quantifying W. bancrofti CFA levels in human blood, which are correlated with adult worm burdens. This tool may be useful for assessing the impact of treatment on adult filarial worms in individuals and communities. PMID:27114288

Alphabetical Index of Parasitic Diseases

MedlinePlus

... Z Index Laboratory Diagnostic Assistance Parasitic Disease and Malaria Strategic Priorities: 2015—2020 About our Division Get ... Lymphatic filariasis (Filariasis, Elephantiasis) Back To Top M Malaria ( Plasmodium Infection) Microsporidiosis ( Microsporidia Infection ) Mite Infestation (Scabies) ...

The Impact of Two Semiannual Treatments with Albendazole Alone on Lymphatic Filariasis and Soil-Transmitted Helminth Infections: A Community-Based Study in the Republic of Congo

PubMed Central

Pion, Sébastien D. S.; Chesnais, Cédric B.; Bopda, Jean; Louya, Frédéric; Fischer, Peter U.; Majewski, Andrew C.; Weil, Gary J.; Boussinesq, Michel; Missamou, François

2015-01-01

Implementation of mass drug administration (MDA) with ivermectin plus albendazole (ALB) for lymphatic filariasis (LF) has been delayed in central Africa because of the risk of serious adverse events in subjects with high Loa loa microfilaremia. We conducted a community trial to assess the impact of semiannual MDA with ALB (400 mg) alone on LF and soil-transmitted helminth (STH) infections in the Republic of Congo. Evaluation at 12 months showed that ALB MDA had not significantly reduced Wuchereria bancrofti antigenemia or microfilaria (mf) rates in the community (from 17.3% to 16.6% and from 5.3% to 4.2%, respectively). However, the geometric mean mf count in mf-positive subjects was reduced from 202.2 to 80.9 mf/mL (60% reduction, P = 0.01). The effect of ALB was impressive in 38 subjects who were mf-positive at baseline and retested at 12 months: 37% had total mf clearance, and individual mf densities were reduced by 73.0%. MDA also dramatically reduced the hookworm infection rate in the community from 6.5% to 0.6% (91% reduction), with less impressive effects on Ascaris and Trichuris. These preliminary results suggest that semiannual community MDA with ALB is a promising strategy for controlling LF and STH in areas with coendemic loiasis. PMID:25758650

Assessment of lymphatic filariasis prior to re-starting mass drug administration campaigns in coastal Kenya.

PubMed

Njenga, Sammy M; Kanyi, Henry M; Mutungi, Faith M; Okoyo, Collins; Matendechero, Hadley S; Pullan, Rachel L; Halliday, Katherine E; Brooker, Simon J; Wamae, C Njeri; Onsongo, Joyce K; Won, Kimberly Y

2017-02-22

Lymphatic filariasis (LF) is a debilitating disease associated with extensive disfigurement and is one of a diverse group of diseases referred to as neglected tropical diseases (NTDs) which mainly occur among the poorest populations. In line with global recommendations to eliminate LF, Kenya launched its LF elimination programme in 2002 with the aim to implement annual mass drug administration (MDA) in order to interrupt LF transmission. However, the programme faced financial and administrative challenges over the years such that sustained annual MDA was not possible. Recently, there has been renewed interest to eliminate LF and the Kenyan Ministry of Health, through support from World Health Organization (WHO), restarted annual MDA in 2015. The objective of this study was to evaluate the current status of LF infection in the endemic coastal region of Kenya before MDA campaigns were restarted. Ten sentinel sites in Kwale, Kilifi, Tana River, Lamu, and Taita-Taveta counties in coastal Kenya were selected for participation in a cross-sectional survey of LF infection prevalence. At least 300 individuals in each sentinel village were sampled through random house-to-house visits. During the day, the point-of-care immunochromatographic test (ICT) was used to detect the presence of Wuchereria bancrofti circulating filarial antigen in finger prick blood samples collected from residents of the selected sentinel villages. Those individuals who tested positive with the ICT test were requested to provide a night-time blood sample for microfilariae (MF) examination. The overall prevalence of filarial antigenaemia was 1.3% (95% CI: 0.9-1.8%). Ndau Island in Lamu County had the highest prevalence (6.3%; 95% CI: 4.1-9.7%), whereas sites in Kilifi and Kwale counties had prevalences < 1.7%. Mean microfilarial density was also higher in Ndau Island (234 MF/ml) compared to sentinel sites in Kwale and Kilifi counties (< 25 MF/ml). No LF infection was detected in Tana River and

Investment Success in Public Health: An Analysis of the Cost-Effectiveness and Cost-Benefit of the Global Programme to Eliminate Lymphatic Filariasis

PubMed Central

Bettis, Alison A.; Chu, Brian K.; McFarland, Deborah A.; Hooper, Pamela J.; Mante, Sunny D.; Fitzpatrick, Christopher; Bradley, Mark H.

2017-01-01

Abstract Background. It has been estimated that $154 million per year will be required during 2015–2020 to continue the Global Programme to Eliminate Lymphatic Filariasis (GPELF). In light of this, it is important to understand the program’s current value. Here, we evaluate the cost-effectiveness and cost-benefit of the preventive chemotherapy that was provided under the GPELF between 2000 and 2014. In addition, we also investigate the potential cost-effectiveness of hydrocele surgery. Methods. Our economic evaluation of preventive chemotherapy was based on previously published health and economic impact estimates (between 2000 and 2014). The delivery costs of treatment were estimated using a model developed by the World Health Organization. We also developed a model to investigate the number of disability-adjusted life years (DALYs) averted by a hydrocelectomy and identified the cost threshold under which it would be considered cost-effective. Results. The projected cost-effectiveness and cost-benefit of preventive chemotherapy were very promising, and this was robust over a wide range of costs and assumptions. When the economic value of the donated drugs was not included, the GPELF would be classed as highly cost-effective. We projected that a typical hydrocelectomy would be classed as highly cost-effective if the surgery cost less than $66 and cost-effective if less than $398 (based on the World Bank’s cost-effectiveness thresholds for low income countries). Conclusions. Both the preventive chemotherapy and hydrocele surgeries provided under the GPELF are incredibly cost-effective and offer a very good investment in public health. PMID:27956460

The combined effect of the Lymphatic Filariasis Elimination Programme and the Schistosomiasis and Soil-transmitted Helminthiasis Control Programme on soil-transmitted helminthiasis in schoolchildren in Tanzania.

PubMed

Massa, Khalid; Magnussen, Pascal; Sheshe, Amir; Ntakamulenga, Robert; Ndawi, Benedict; Olsen, Annette

2009-01-01

The combined effect of the Lymphatic Filariasis Elimination Programme (LFEP) and the National Schistosomiasis and Soil-transmitted Helminthiasis Control Programme (NSSCP) on soil-transmitted helminthiasis (STH) was evaluated. In September 2004, before mass drug administration (MDA) with ivermectin and albendazole by the LFEP in October, the prevalence and intensity of STH were recorded in 228 pupils in one primary school. After 8 months, all available pupils were re-examined, and the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm had decreased from 0.9 to 0.7% (P=0.84), from 4.8 to 0.7% (P=0.004) and from 45.6 to 11.9% (P<0.001), respectively. Overall, 81.2% of the schoolchildren stated that they were treated by the LFEP in October 2004. After the 8 months follow-up, pupils were treated with praziquantel and albendazole by the present project (substitute for the NSSCP). After another 4 months (at 12 months follow-up), the prevalence of hookworm infection was reduced to 4.8% (P=0.003), while the prevalence of T. trichiura was reduced to 0.3% (P=0.54) and the prevalence of A. lumbricoides remained unchanged. Mass co-administration of ivermectin and albendazole by the LFEP had a significant effect on STH, which was further amplified by treatment with praziquantel and albendazole 4 months later.

The impact of two semiannual treatments with albendazole alone on lymphatic filariasis and soil-transmitted helminth infections: a community-based study in the Republic of Congo.

PubMed

Pion, Sébastien D S; Chesnais, Cédric B; Bopda, Jean; Louya, Frédéric; Fischer, Peter U; Majewski, Andrew C; Weil, Gary J; Boussinesq, Michel; Missamou, François

2015-05-01

Implementation of mass drug administration (MDA) with ivermectin plus albendazole (ALB) for lymphatic filariasis (LF) has been delayed in central Africa because of the risk of serious adverse events in subjects with high Loa loa microfilaremia. We conducted a community trial to assess the impact of semiannual MDA with ALB (400 mg) alone on LF and soil-transmitted helminth (STH) infections in the Republic of Congo. Evaluation at 12 months showed that ALB MDA had not significantly reduced Wuchereria bancrofti antigenemia or microfilaria (mf) rates in the community (from 17.3% to 16.6% and from 5.3% to 4.2%, respectively). However, the geometric mean mf count in mf-positive subjects was reduced from 202.2 to 80.9 mf/mL (60% reduction, P = 0.01). The effect of ALB was impressive in 38 subjects who were mf-positive at baseline and retested at 12 months: 37% had total mf clearance, and individual mf densities were reduced by 73.0%. MDA also dramatically reduced the hookworm infection rate in the community from 6.5% to 0.6% (91% reduction), with less impressive effects on Ascaris and Trichuris. These preliminary results suggest that semiannual community MDA with ALB is a promising strategy for controlling LF and STH in areas with coendemic loiasis. © The American Society of Tropical Medicine and Hygiene.

Investment Success in Public Health: An Analysis of the Cost-Effectiveness and Cost-Benefit of the Global Programme to Eliminate Lymphatic Filariasis.

PubMed

Turner, Hugo C; Bettis, Alison A; Chu, Brian K; McFarland, Deborah A; Hooper, Pamela J; Mante, Sunny D; Fitzpatrick, Christopher; Bradley, Mark H

2017-03-15

It has been estimated that $154 million per year will be required during 2015-2020 to continue the Global Programme to Eliminate Lymphatic Filariasis (GPELF). In light of this, it is important to understand the program's current value. Here, we evaluate the cost-effectiveness and cost-benefit of the preventive chemotherapy that was provided under the GPELF between 2000 and 2014. In addition, we also investigate the potential cost-effectiveness of hydrocele surgery. Our economic evaluation of preventive chemotherapy was based on previously published health and economic impact estimates (between 2000 and 2014). The delivery costs of treatment were estimated using a model developed by the World Health Organization. We also developed a model to investigate the number of disability-adjusted life years (DALYs) averted by a hydrocelectomy and identified the cost threshold under which it would be considered cost-effective. The projected cost-effectiveness and cost-benefit of preventive chemotherapy were very promising, and this was robust over a wide range of costs and assumptions. When the economic value of the donated drugs was not included, the GPELF would be classed as highly cost-effective. We projected that a typical hydrocelectomy would be classed as highly cost-effective if the surgery cost less than $66 and cost-effective if less than $398 (based on the World Bank's cost-effectiveness thresholds for low income countries). Both the preventive chemotherapy and hydrocele surgeries provided under the GPELF are incredibly cost-effective and offer a very good investment in public health. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

Positivity of Antigen Tests Used for Diagnosis of Lymphatic Filariasis in Individuals Without Wuchereria bancrofti Infection But with High Loa loa Microfilaremia

PubMed Central

Pion, Sébastien D.; Montavon, Céline; Chesnais, Cédric B.; Kamgno, Joseph; Wanji, Samuel; Klion, Amy D.; Nutman, Thomas B.; Boussinesq, Michel

2016-01-01

Since the mid-2000s, the immunochromatographic card test (ICT), a point-of-care test for detecting Wuchereria bancrofti circulating filarial antigens (CFAs), has been the backbone for mapping and monitoring lymphatic filariasis (LF) worldwide. Recently, there have been instances in which CFA positivity has been associated with Loa loa microfilaremia. Here, we examined the association, at both the community and individual levels, between L. loa and CFA using additional diagnostic tools (quantitative polymerase chain reaction [qPCR], Og4C3 enzyme-linked immunosorbent assay, and IgG4 antibodies to Wb123 assays) to demonstrate the relationship between L. loa microfilaremia and ICT positivity. In May 2013, peripheral blood was collected during the day from 1,812 individuals living in southern Cameroon. ICT tests were done on the spot, and positive individuals were resampled at night. Results of qPCR and Wb123 assays concurred proving the absence of W. bancrofti infection. Og4C3 assays indicate a quantitative relationship between the level of L. loa microfilaremia and that of CFA. This was confirmed by epidemiological analyses, which reveal a strong association between L. loa microfilaremia and ICT positivity, with 50% of ICT reacting to L. loa when its microfilarial density exceeds 30,000 microfilariae/mL. At the community level, the proportion of positive ICT would exceed 2% when the prevalence of L. loa microfilaremia in the total population is above 20%. This has significant implications in terms of mapping and control of LF caused by W. bancrofti in Loa-endemic areas. Cross-reactivity of ICT with L. loa has to be considered in the context of both individual and community diagnostics. PMID:27729568

Prevalence of Wuchereria bancrofti infection in some coastal villages of Ganjam, Orissa.

PubMed

Kumar, A; Chand, S K

1990-09-01

The endemicity of filariasis was assessed in 42 villages of coastal Keluapalli PHC in Ganjam District of Orissa. Prevalence was found to vary greatly between extreme coastal and subcoastal villages. The infection was non existent in 12 coastal villages. Age and sexwise distribution of filariasis cases have been analysed and presented.

Low incidence of helminth infections (schistosomiasis, strongyloidiasis, filariasis, toxocariasis) among Dutch long-term travelers: A prospective study, 2008-2011.

PubMed

Overbosch, Femke W; van Gool, Tom; Matser, Amy; Sonder, Gerard J B

2018-01-01

Despite the considerable burden of helminth infections in developing countries and increasing international travel, little is known about the risks of infection for travelers. We studied the attack and incidence rate of serology confirmed strongyloidiasis, filariasis, and toxocariasis among long-term travelers and associated factors. A second objective was to evaluate eosinophilia as a positive/negative predictive value (PPV/NPV) for a recent helminth infection. From 2008 to 2011, clients of the Public Health Service travel clinic planning travel to (sub)tropical countries for 12-52 weeks were invited to participate in a prospective study. Participants kept a weekly diary, recording itinerary, symptoms, and physician visits during travel and completed a post-travel questionnaire. Pre- and post-travel blood samples were serologically tested for the presence of IgG antibodies against Schistosoma species, Strongyloides stercoralis, filarial species, and Toxacara species and were used for a blood cell count. Factors associated with recent infection were analyzed using Poisson regression. Differences among groups of travelers were studied using chi square tests. For the 604 participants, median age was 25 years (interquartile range [IQR]: 23-29), 36% were male, median travel duration was 20 weeks (IQR: 15-25), and travel purpose was predominantly tourism (62%). Destinations were Asia (45%), Africa (18%), and the Americas (37%). Evidence of previous infection was found in 13/604 participants: antibodies against Schistosoma spp. in 5 (0.8%), against S.stercoralis in 3 (0.5%), against filarial species in 4 (0.7%), and against Toxocara spp. in 1 (0.2%). Ten recent infections were found in 9 participants (3, 1, 6, 0 cases, in the above order), making the attack rates 0.61, 0.17, 1.1 and 0, and the incidence rates per 1000 person-months 1.5, 0.34, 2.6 and 0. The overall PPV and NPV of eosinophila for recent infection were 0 and 98%, respectively. The risk of the helminth

Loa loa vectors Chrysops spp.: perspectives on research, distribution, bionomics, and implications for elimination of lymphatic filariasis and onchocerciasis.

PubMed

Kelly-Hope, Louise; Paulo, Rossely; Thomas, Brent; Brito, Miguel; Unnasch, Thomas R; Molyneux, David

2017-04-05

Loiasis is a filarial disease caused Loa loa. The main vectors are Chrysops silacea and C. dimidiata which are confined to the tropical rainforests of Central and West Africa. Loiasis is a mild disease, but individuals with high microfilaria loads may suffer from severe adverse events if treated with ivermectin during mass drug administration campaigns for the elimination of lymphatic filariasis and onchocerciasis. This poses significant challenges for elimination programmes and alternative interventions are required in L. loa co-endemic areas. The control of Chrysops has not been considered as a viable cost-effective intervention; we reviewed the current knowledge of Chrysops vectors to assess the potential for control as well as identified areas for future research. We identified 89 primary published documents on the two main L. loa vectors C. silacea and C dimidiata. These were collated into a database summarising the publication, field and laboratory procedures, species distributions, ecology, habitats and methods of vector control. The majority of articles were from the 1950-1960s. Field studies conducted in Cameroon, Democratic Republic of Congo, Equatorial Guinea, Nigeria and Sudan highlighted that C. silacea is the most important and widespread vector. This species breeds in muddy streams or swampy areas of forests or plantations, descends from forest canopies to feed on humans during the day, is more readily adapted to human dwellings and attracted to wood fires. Main vector targeted measures proposed to impact on L. loa transmission included personal repellents, household screening, indoor residual spraying, community-based environmental management, adulticiding and larviciding. This is the first comprehensive review of the major L. loa vectors for several decades. It highlights key vector transmission characteristics that may be targeted for vector control providing insights into the potential for integrated vector management, with multiple diseases

Progress and Impact of 13 Years of the Global Programme to Eliminate Lymphatic Filariasis on Reducing the Burden of Filarial Disease

PubMed Central

Ramaiah, K. D.; Ottesen, Eric A.

2014-01-01

Background A Global Programme to Eliminate Lymphatic Filariasis was launched in 2000, with mass drug administration (MDA) as the core strategy of the programme. After completing 13 years of operations through 2012 and with MDA in place in 55 of 73 endemic countries, the impact of the MDA programme on microfilaraemia, hydrocele and lymphedema is in need of being assessed. Methodology/Principal findings During 2000–2012, the MDA programme made remarkable achievements – a total of 6.37 billion treatments were offered and an estimated 4.45 billion treatments were consumed by the population living in endemic areas. Using a model based on empirical observations of the effects of treatment on clinical manifestations, it is estimated that 96.71 million LF cases, including 79.20 million microfilaria carriers, 18.73 million hydrocele cases and a minimum of 5.49 million lymphedema cases have been prevented or cured during this period. Consequently, the global prevalence of LF is calculated to have fallen by 59%, from 3.55% to 1.47%. The fall was highest for microfilaraemia prevalence (68%), followed by 49% in hydrocele prevalence and 25% in lymphedema prevalence. It is estimated that, currently, i.e. after 13 years of the MDA programme, there are still an estimated 67.88 million LF cases that include 36.45 million microfilaria carriers, 19.43 million hydrocele cases and 16.68 million lymphedema cases. Conclusions/Significance The MDA programme has resulted in significant reduction of the LF burden. Extension of MDA to all at-risk countries and to all regions within those countries where MDA has not yet reached 100% geographic coverage is imperative to further reduce the number of microfilaraemia and chronic disease cases and to reach the global target of interrupting transmission of LF by 2020. PMID:25412180

Assessing Lymphatic Filariasis Data Quality in Endemic Communities in Ghana, Using the Neglected Tropical Diseases Data Quality Assessment Tool for Preventive Chemotherapy.

PubMed

de Souza, Dziedzom K; Yirenkyi, Eric; Otchere, Joseph; Biritwum, Nana-Kwadwo; Ameme, Donne K; Sackey, Samuel; Ahorlu, Collins; Wilson, Michael D

2016-03-01

The activities of the Global Programme for the Elimination of Lymphatic Filariasis have been in operation since the year 2000, with Mass Drug Administration (MDA) undertaken yearly in disease endemic communities. Information collected during MDA-such as population demographics, age, sex, drugs used and remaining, and therapeutic and geographic coverage-can be used to assess the quality of the data reported. To assist country programmes in evaluating the information reported, the WHO, in collaboration with NTD partners, including ENVISION/RTI, developed an NTD Data Quality Assessment (DQA) tool, for use by programmes. This study was undertaken to evaluate the tool and assess the quality of data reported in some endemic communities in Ghana. A cross sectional study, involving review of data registers and interview of drug distributors, disease control officers, and health information officers using the NTD DQA tool, was carried out in selected communities in three LF endemic Districts in Ghana. Data registers for service delivery points were obtained from District health office for assessment. The assessment verified reported results in comparison with recounted values for five indicators: number of tablets received, number of tablets used, number of tablets remaining, MDA coverage, and population treated. Furthermore, drug distributors, disease control officers, and health information officers (at the first data aggregation level), were interviewed, using the DQA tool, to determine the performance of the functional areas of the data management system. The results showed that over 60% of the data reported were inaccurate, and exposed the challenges and limitations of the data management system. The DQA tool is a very useful monitoring and evaluation (M&E) tool that can be used to elucidate and address data quality issues in various NTD control programmes.

Positivity of Antigen Tests Used for Diagnosis of Lymphatic Filariasis in Individuals Without Wuchereria bancrofti Infection But with High Loa loa Microfilaremia.

PubMed

Pion, Sébastien D; Montavon, Céline; Chesnais, Cédric B; Kamgno, Joseph; Wanji, Samuel; Klion, Amy D; Nutman, Thomas B; Boussinesq, Michel

2016-12-07

Since the mid-2000s, the immunochromatographic card test (ICT), a point-of-care test for detecting Wuchereria bancrofti circulating filarial antigens (CFAs), has been the backbone for mapping and monitoring lymphatic filariasis (LF) worldwide. Recently, there have been instances in which CFA positivity has been associated with Loa loa microfilaremia. Here, we examined the association, at both the community and individual levels, between L. loa and CFA using additional diagnostic tools (quantitative polymerase chain reaction [qPCR], Og4C3 enzyme-linked immunosorbent assay, and IgG4 antibodies to Wb123 assays) to demonstrate the relationship between L. loa microfilaremia and ICT positivity. In May 2013, peripheral blood was collected during the day from 1,812 individuals living in southern Cameroon. ICT tests were done on the spot, and positive individuals were resampled at night. Results of qPCR and Wb123 assays concurred proving the absence of W. bancrofti infection. Og4C3 assays indicate a quantitative relationship between the level of L. loa microfilaremia and that of CFA. This was confirmed by epidemiological analyses, which reveal a strong association between L. loa microfilaremia and ICT positivity, with 50% of ICT reacting to L. loa when its microfilarial density exceeds 30,000 microfilariae/mL. At the community level, the proportion of positive ICT would exceed 2% when the prevalence of L. loa microfilaremia in the total population is above 20%. This has significant implications in terms of mapping and control of LF caused by W. bancrofti in Loa-endemic areas. Cross-reactivity of ICT with L. loa has to be considered in the context of both individual and community diagnostics. © The American Society of Tropical Medicine and Hygiene.

Efficacy of the Volatile Oil from Water Celery (Helosciadium nodiflorum, Apiaceae) against the Filariasis Vector Culex quinquefasciatus, the Housefly Musca domestica, and the African Cotton Leafworm Spodoptera littoralis.

PubMed

Benelli, Giovanni; Pavela, Roman; Ricciutelli, Massimo; Lupidi, Giulio; Maggi, Filippo

2017-12-01

Water celery (Helosciadium nodiflorum, Apiaceae) is a common and invasive hydrophyte occurring in rivers and slow waters of Europe. In the past, it was consumed as a vegetable and spices, but currently it has mostly been abandoned. As a result, this plant produces an unexploited biomass occluding rivers and slow waters. With the aim to valorise water celery as an important biomass source for the development of botanical insecticides, in this work, we investigated the inhibitory effects of the essential oil hydrodistilled from its aerial parts against larvae of the filariasis vector Culex quinquefasciatus, adults of the housefly Musca domestica, and larvae of the African cotton leafworm Spodoptera littoralis. The essential oil, which was characterized by the insecticidal limonene (39.8%) and myristicin (35.3%), exerted important toxic effects on 3rd instar larvae of C. quinquefasciatus and S. littoralis and on adults of M. domestica, with LD 50 of 50.4 μl l -1 , 116.7 μg larva -1 , and 45.1 (male) and 70.1 (female) μg adult -1 , respectively. The oil did not show any noticeable inhibitory activity on the acetylcholinesterase enzyme. Our findings add scientific evidences highlighting water celery as an important biomass source to be used for the control of insect pests and vectors of high economic importance. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Pilot assessment of soil-transmitted helminthiasis in the context of transmission assessment surveys for lymphatic filariasis in Benin and Tonga.

PubMed

Chu, Brian K; Gass, Katherine; Batcho, Wilfrid; 'Ake, Malakai; Dorkenoo, Améyo M; Adjinacou, Elvire; Mafi, 'Eva; Addiss, David G

2014-02-01

Mass drug administration (MDA) for lymphatic filariasis (LF) programs has delivered more than 2 billion treatments of albendazole, in combination with either ivermectin or diethylcarbamazine, to communities co-endemic for soil-transmitted helminthiasis (STH), reducing the prevalence of both diseases. A transmission assessment survey (TAS) is recommended to determine if MDA for LF can be stopped within an evaluation unit (EU) after at least five rounds of annual treatment. The TAS also provides an opportunity to simultaneously assess the impact of these MDAs on STH and to determine the frequency of school-based MDA for STH after community-wide MDA is no longer needed for LF. Pilot studies conducted in Benin and Tonga assessed the feasibility of a coordinated approach. Of the schools (clusters) selected for a TAS in each EU, a subset of 5 schools per STH ecological zone was randomly selected, according to World Health Organization (WHO) guidelines, for the coordinated survey. In Benin, 519 children were sampled in 5 schools and 22 (4.2%) had STH infection (A. lumbricoides, T. trichiura, or hookworm) detected using the Kato-Katz method. All infections were classified as light intensity under WHO criteria. In Tonga, 10 schools were chosen for the coordinated TAS and STH survey covering two ecological zones; 32 of 232 (13.8%) children were infected in Tongatapu and 82 of 320 (25.6%) in Vava'u and Ha'apai. All infections were light-intensity with the exception of one with moderate-intensity T. trichiura. Synchronous assessment of STH with TAS is feasible and provides a well-timed evaluation of infection prevalence to guide ongoing treatment decisions at a time when MDA for LF may be stopped. The coordinated field experiences in both countries also suggest potential time and cost savings. Refinement of a coordinated TAS and STH sampling methodology should be pursued, along with further validation of alternative quantitative diagnostic tests for STH that can be used with

Pilot Assessment of Soil-Transmitted Helminthiasis in the Context of Transmission Assessment Surveys for Lymphatic Filariasis in Benin and Tonga

PubMed Central

Chu, Brian K.; Gass, Katherine; Batcho, Wilfrid; 'Ake, Malakai; Dorkenoo, Améyo M.; Adjinacou, Elvire; Mafi, 'Eva; Addiss, David G.

2014-01-01

Background Mass drug administration (MDA) for lymphatic filariasis (LF) programs has delivered more than 2 billion treatments of albendazole, in combination with either ivermectin or diethylcarbamazine, to communities co-endemic for soil-transmitted helminthiasis (STH), reducing the prevalence of both diseases. A transmission assessment survey (TAS) is recommended to determine if MDA for LF can be stopped within an evaluation unit (EU) after at least five rounds of annual treatment. The TAS also provides an opportunity to simultaneously assess the impact of these MDAs on STH and to determine the frequency of school-based MDA for STH after community-wide MDA is no longer needed for LF. Methodology/Principal Findings Pilot studies conducted in Benin and Tonga assessed the feasibility of a coordinated approach. Of the schools (clusters) selected for a TAS in each EU, a subset of 5 schools per STH ecological zone was randomly selected, according to World Health Organization (WHO) guidelines, for the coordinated survey. In Benin, 519 children were sampled in 5 schools and 22 (4.2%) had STH infection (A. lumbricoides, T. trichiura, or hookworm) detected using the Kato-Katz method. All infections were classified as light intensity under WHO criteria. In Tonga, 10 schools were chosen for the coordinated TAS and STH survey covering two ecological zones; 32 of 232 (13.8%) children were infected in Tongatapu and 82 of 320 (25.6%) in Vava'u and Ha'apai. All infections were light-intensity with the exception of one with moderate-intensity T. trichiura. Conclusions Synchronous assessment of STH with TAS is feasible and provides a well-timed evaluation of infection prevalence to guide ongoing treatment decisions at a time when MDA for LF may be stopped. The coordinated field experiences in both countries also suggest potential time and cost savings. Refinement of a coordinated TAS and STH sampling methodology should be pursued, along with further validation of alternative

Lymphatic filariasis patient identification in a large urban area of Tanzania: An application of a community-led mHealth system.

PubMed

Mwingira, Upendo; Chikawe, Maria; Mandara, Wilfred Lazarus; Mableson, Hayley E; Uisso, Cecilia; Mremi, Irene; Malishee, Alpha; Malecela, Mwele; Mackenzie, Charles D; Kelly-Hope, Louise A; Stanton, Michelle C

2017-07-01

Lymphatic filariasis (LF) is best known for the disabling and disfiguring clinical conditions that infected patients can develop; providing care for these individuals is a major goal of the Global Programme to Eliminate LF. Methods of locating these patients, knowing their true number and thus providing care for them, remains a challenge for national medical systems, particularly when the endemic zone is a large urban area. A health community-led door-to-door survey approach using the SMS reporting tool MeasureSMS-Morbidity was used to rapidly collate and monitor data on LF patients in real-time (location, sex, age, clinical condition) in Dar es Salaam, Tanzania. Each stage of the phased study carried out in the three urban districts of city consisted of a training period, a patient identification and reporting period, and a data verification period, with refinements to the system being made after each phase. A total of 6889 patients were reported (133.6 per 100,000 population), of which 4169 were reported to have hydrocoele (80.9 per 100,000), 2251 lymphoedema-elephantiasis (LE) (43.7 per 100,000) and 469 with both conditions (9.1 per 100,000). Kinondoni had the highest number of reported patients in absolute terms (2846, 138.9 per 100,000), followed by Temeke (2550, 157.3 per 100,000) and Ilala (1493, 100.5 per 100,000). The number of hydrocoele patients was almost twice that of LE in all three districts. Severe LE patients accounted for approximately a quarter (26.9%) of those reported, with the number of acute attacks increasing with reported LE severity (1.34 in mild cases, 1.78 in moderate cases, 2.52 in severe). Verification checks supported these findings. This system of identifying, recording and mapping patients affected by LF greatly assists in planning, locating and prioritising, as well as initiating, appropriate morbidity management and disability prevention (MMDP) activities. The approach is a feasible framework that could be used in other large

Filarial pleural effusion without peripheral blood or pleural fluid eosinophilia.

PubMed

Shukla, Amitabh Das; Chaudhary, Abhinav; Verma, Arvind Kumar; Anantha, Shreenivasa

2017-09-19

Lymphatic filariasis is a tropical parasitic disease and is endemic in India. It is present in various forms but its manifestation as pleural effusion is rare. Here, we describe a case of 58-year-old male who presented with complaint of left side chest pain and breathlessness. He was investigated and diagnosed as a case of left side pleural effusion due to filariasis, with peripheral blood lymphocytosis but without peripheral blood or pleural fluid eosinophilia. Our case foregrounds that filariasis can present with peripheral blood lymphocytosis and without peripheral blood or pleural fluid eosinophilia. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Lymphatic filariasis mapping by Immunochromatographic Test cards and baseline microfilaria survey prior to mass drug administration in Sierra Leone

PubMed Central

2012-01-01

Background National mapping of lymphatic filariasis (LF) was conducted using Immunochromatographic tests (ICT) in 2005 to determine endemicity and geographic spread of the disease. A baseline microfilaria survey was then conducted to determine LF prevalence and microfilaria intensity. Methods In 2005 1,982 persons of 15 years and over from 14 health districts were selected and fingertip blood samples were tested with ICT cards. In 2007-8 blood samples were taken between 10 p.m. and 2 a.m. and examined for microfilaria (mf) from 9,288 persons from 16 sentinel sites representing each district and 2 additional sites for districts with populations over 500,000 (Bo and Kenema). Results The overall LF prevalence by ICT cards was 21% (males 28%, females 15%). All districts had a prevalence of Wuchereria bancrofti antigen > 1%. Distribution of LF prevalence showed a strong spatial correlation pattern with high prevalence in a large area in the northeast gradually decreasing to a relatively low prevalence in the southwest coast. High prevalence was found in the northeast, Bombali (52%), Koinadugu (46%), Tonkolili (37%) and Kono (30%). Low prevalence was found in the southwest, Bonthe (3%) and Pujehun (4%). The mf prevalence was higher in the northeast: Bombali, 6.7%, Koinadugu 5.7%, Port Loko 4.4% and Kono 2.4%. Overall there was a significant difference in mf prevalence by gender: males 2.9%, females 1.8% (p = 0.0002) and within districts in Kailahun, Kono, Port Loko, Moyamba and Koinadugu (all p < 0.05). The mf prevalence was higher in people > 20 years (2.5%) than in people ≤ 20 years (1.7%) (p = 0.043). The overall arithmetic mean mf density was 50.30 mf/ml among mf-positive individuals and 1.19 mf/ml in the population examined which varied significantly between districts. Conclusions The ICT results showed that LF was endemic nationwide and that preventive chemotherapy (PCT) was justified across the country. Both the ICT and microfilaraemia surveys found that

Human Immunodeficiency Virus, Antiretroviral Therapy and Markers of Lymphatic Filariasis Infection: A Cross-sectional Study in Rural Northern Malawi

PubMed Central

Tafatatha, Terence; Taegtmeyer, Miriam; Ngwira, Bagrey; Phiri, Amos; Kondowe, Mariot; Piston, Wilson; Molesworth, Anna; Kayuni, Ndoliwe; Koole, Olivier; Crampin, Amelia; Horton, John; French, Neil

2015-01-01

Background Lymphatic filariasis (LF) and human immunodeficiency virus (HIV) are major public health problems. Individuals may be co-infected, raising the possibility of important interactions between these two pathogens with consequences for LF elimination through annual mass drug administration (MDA). Methodology and Principal Findings We analysed circulating filarial antigenaemia (CFA) by HIV infection status among adults in two sites in northern Malawi, a region endemic for both LF and HIV. Stored blood samples and data from two geographically separate studies were used: one a recruitment phase of a clinical trial of anti-filarial agent dosing regimens, and the other a whole population annual HIV sero-survey. In study one, 1,851 consecutive adult volunteers were screened for HIV and LF infection. CFA prevalence was 25.4% (43/169) in HIV-positive and 23.6% (351/1487) in HIV-negative participants (p=0.57). Geometric mean CFA concentrations were 859 and 1660 antigen units per ml of blood (Ag/ml) respectively, geometric mean ratio (GMR) 0.85, 95%CI 0.49-1.50. In 7,863 adults in study two, CFA prevalence was 20.9% (86/411) in HIV-positive and 24.0% (1789/7452) in HIV–negative participants (p=0.15). Geometric mean CFA concentrations were 630 and 839 Ag/ml respectively (GMR 0.75, 95%CI 0.60-0.94). In the HIV-positive group, antiretroviral therapy (ART) use was associated with a lower CFA prevalence, 12.7% (18/142) vs. 25.3% (67/265), (OR 0.43, 95%CI 0.24-0.76). Prevalence of CFA decreased with duration of ART use, 15.2% 0-1 year (n=59), 13.6% >1-2 years (n=44), 10.0% >2-3 years (n=30) and 0% >3-4 years treatment (n=9), p<0.01 χ2 for linear trend. Conclusions/Significance In this large cross-sectional study of two distinct LF-exposed populations, there is no evidence that HIV infection has an impact on LF epidemiology that will interfere with LF control measures. A significant association of ART use with lower CFA prevalence merits further investigation to understand

The past matters: estimating intrinsic hookworm transmission intensity in areas with past mass drug administration to control lymphatic filariasis.

PubMed

Werkman, Marleen; Truscott, James E; Toor, Jaspreet; Wright, James E; Anderson, Roy M

2017-05-23

Current WHO guidelines for soil-transmitted helminth (STH) control focus on mass drug administration (MDA) targeting preschool-aged (pre-SAC) and school-aged children (SAC), with the goal of eliminating STH as a public health problem amongst children. Recently, attention and funding has turned towards the question whether MDA alone can result in the interruption of transmission for STH. The lymphatic filariasis (LF) elimination programme, have been successful in reaching whole communities. There is the possibility of building upon the infrastructure created for these LF-programmes to enhance the control of STH. Using hookworm as an example, we explore what further MDA coverage might be required to induce interruption of transmission for hookworm in the wake of a successful LF programme. Analyses based on the model of STH transmission and MDA impact predict the effects of previous LF control by MDA over five years, on a defined baseline prevalence of STH in an area with a defined transmission intensity (the basic reproductive number R 0 ). If the LF MDA programme achieved a high coverage (70, 70 and 60% for pre-SAC, SAC and adults, respectively) we expect that in communities with a hookworm prevalence of 15%, after 5 years of LF control, the intrinsic R 0 value in that setting is 2.47. By contrast, if lower LF coverages were achieved (40, 40 and 30% for pre-SAC, SAC and adults, respectively), with the same prevalence of 15% at baseline (after 5 years of LF MDA), the intrinsic hookworm R 0 value is predicted to be 1.67. The intrinsic R 0 value has a large effect on the expected successes of follow-up STH programmes post LF MDA. Consequently, the outcomes of identical programmes may differ between these communities. To design the optimal MDA intervention to eliminate STH infections, it is vital to have information on historical MDA programmes and baseline prevalence to estimate the intrinsic transmission intensity for the defined setting (R 0 ). The baseline

Lymphatic Filariasis

MedlinePlus

... stained with Giemsa. Center: Photograph of a female Aedes aegypti mosquito as she was in the process of obtaining a “blood meal.” Laboratory strains of Aedes aegypti can be infected with Brugia. Credit: DPDx , ...

Toxicity of β-citronellol, geraniol and linalool from Pelargonium roseum essential oil against the West Nile and filariasis vector Culex pipiens (Diptera: Culicidae).

PubMed

Tabari, Mohaddeseh Abouhosseini; Youssefi, Mohammad Reza; Esfandiari, Aryan; Benelli, Giovanni

2017-10-01

Insect vectors are responsible for spreading devastating parasites and pathogens. A large number of botanicals have been suggested for eco-friendly control programs against mosquito vectors, and some of them are aromatic plants. Pelargonium roseum, a species belonging to the Geraniaceae family, due to its pleasant rose-like odor may represent a suitable candidate as mosquito repellent and/or larvicide. In this research, we evaluated the toxicity of the essential oil from P. roseum and its major constituents against the West Nile and filariasis vector Culex pipiens. The chemical composition of P. roseum essential oil was analyzed by gas chromatography-mass spectroscopy. Major constituents were citronellol (35.9%), geraniol (18.5%), and linalool (5.72%). The bioactivity of P. roseum essential oil and its three major compounds on larvae and egg rafts of Cx. pipiens was evaluated. The essential oil had a significant toxic effect on larvae and egg rafts of Cx. pipiens, with 50% lethal concentration (LC 50 ) values of 5.49 and 0.45μg/mL, respectively. Major constituents, geraniol, citronellol and linalool resulted in LC 50 values of 6.86, 7.64 and 14.87μg/mL on larvae, and 0.8, 0.67 and 1.27μg/mL on egg rafts. Essential oil and two of its constituents, citronellol and geraniol showed moderate knock-down on Cx. pipiens adults. Overall, the present investigation revealed that the major components of P. roseum and specially the whole essential oil could be helpful in developing novel and safe mosquito control tools and also offer an environmentally safe and cheap tool for reducing Cx. pipiens mosquito populations. Copyright © 2017. Published by Elsevier Ltd.

No Evidence for Lymphatic Filariasis Transmission in Big Cities Affected by Conflict Related Rural-Urban Migration in Sierra Leone and Liberia

PubMed Central

de Souza, Dziedzom K.; Sesay, Santigie; Moore, Marnijina G.; Ansumana, Rashid; Narh, Charles A.; Kollie, Karsor; Rebollo, Maria P.; Koudou, Benjamin G.; Koroma, Joseph B.; Bolay, Fatorma K.; Boakye, Daniel A.; Bockarie, Moses J.

2014-01-01

Background In West Africa, the principal vectors of lymphatic filariasis (LF) are Anopheles species with Culex species playing only a minor role in transmission, if any. Being a predominantly rural disease, the question remains whether conflict-related migration of rural populations into urban areas would be sufficient for active transmission of the parasite. Methodology/Principal Findings We examined LF transmission in urban areas in post-conflict Sierra Leone and Liberia that experienced significant rural-urban migration. Mosquitoes from Freetown and Monrovia, were analyzed for infection with Wuchereria bancrofti. We also undertook a transmission assessment survey (TAS) in Bo and Pujehun districts in Sierra Leone. The majority of the mosquitoes collected were Culex species, while Anopheles species were present in low numbers. The mosquitoes were analyzed in pools, with a maximum of 20 mosquitoes per pool. In both countries, a total of 1731 An. gambiae and 14342 Culex were analyzed for W. bancrofti, using the PCR. Two pools of Culex mosquitoes and 1 pool of An. gambiae were found infected from one community in Freetown. Pool screening analysis indicated a maximum likelihood of infection of 0.004 (95% CI of 0.00012–0.021) and 0.015 (95% CI of 0.0018–0.052) for the An. gambiae and Culex respectively. The results indicate that An. gambiae is present in low numbers, with a microfilaria prevalence breaking threshold value not sufficient to maintain transmission. The results of the TAS in Bo and Pujehun also indicated an antigen prevalence of 0.19% and 0.67% in children, respectively. This is well below the recommended 2% level for stopping MDA in Anopheles transmission areas, according to WHO guidelines. Conclusions We found no evidence for active transmission of LF in cities, where internally displaced persons from rural areas lived for many years during the more than 10 years conflict in Sierra Leone and Liberia. PMID:24516686

Geographical Factors Affecting Bed Net Ownership, a Tool for the Elimination of Anopheles-Transmitted Lymphatic Filariasis in Hard-to-Reach Communities

PubMed Central

Stanton, Michelle C.; Bockarie, Moses J.; Kelly-Hope, Louise A.

2013-01-01

Vector control, including the use of bed nets, is recommended as a possible strategy for eliminating lymphatic filariasis (LF) in post-conflict countries such as the Democratic Republic of Congo (DRC). This study examined the geographical factors that influence bed net ownership in DRC in order to identify hard-to-reach communities that need to be better targeted. In particular, urban/rural differences and the influence of population density, proximity to cities and health facilities, plus access to major transport networks were investigated. Demographic and Health Survey geo-referenced cluster level data were used to map bed net coverage (proportion of households with at least one of any type of bed net or at least one insecticide-treated net (ITN)), and ITN density (ITNs per person) for 260 clusters. Bivariate and multiple logistic or Poisson regression analyses were used to determine significant relationships. Overall, bed net (30%) and ITN (9%) coverage were very low with significant differences found between urban and rural clusters. In rural clusters, ITN coverage/density was positively correlated with population density (r = 0.25, 0.27 respectively, p<0.01), and negatively with the distance to the two largest cities, Kinshasa or Lubumbashi (r = −0.28, −0.30 respectively, p<0.0001). Further, ownership was significantly negatively correlated with distance to primary national roads and railways (all three measures), distance to main rivers (any bed net only) and distance to the nearest health facility (ITNs only). Logistic and Poisson regression models fitted to the rural cluster data indicated that, after controlling for measured covariates, ownership levels in the Bas-Congo province close to Kinshasa were much larger than that of other provinces. This was most noticeable when considering ITN coverage (odds ratio: 5.3, 95% CI: 3.67–7.70). This analysis provides key insights into the barriers of bed net ownership, which will help inform both LF

Geographical factors affecting bed net ownership, a tool for the elimination of Anopheles-transmitted lymphatic filariasis in hard-to-reach communities.

PubMed

Stanton, Michelle C; Bockarie, Moses J; Kelly-Hope, Louise A

2013-01-01

Vector control, including the use of bed nets, is recommended as a possible strategy for eliminating lymphatic filariasis (LF) in post-conflict countries such as the Democratic Republic of Congo (DRC). This study examined the geographical factors that influence bed net ownership in DRC in order to identify hard-to-reach communities that need to be better targeted. In particular, urban/rural differences and the influence of population density, proximity to cities and health facilities, plus access to major transport networks were investigated. Demographic and Health Survey geo-referenced cluster level data were used to map bed net coverage (proportion of households with at least one of any type of bed net or at least one insecticide-treated net (ITN)), and ITN density (ITNs per person) for 260 clusters. Bivariate and multiple logistic or Poisson regression analyses were used to determine significant relationships. Overall, bed net (30%) and ITN (9%) coverage were very low with significant differences found between urban and rural clusters. In rural clusters, ITN coverage/density was positively correlated with population density (r = 0.25, 0.27 respectively, p<0.01), and negatively with the distance to the two largest cities, Kinshasa or Lubumbashi (r = -0.28, -0.30 respectively, p<0.0001). Further, ownership was significantly negatively correlated with distance to primary national roads and railways (all three measures), distance to main rivers (any bed net only) and distance to the nearest health facility (ITNs only). Logistic and Poisson regression models fitted to the rural cluster data indicated that, after controlling for measured covariates, ownership levels in the Bas-Congo province close to Kinshasa were much larger than that of other provinces. This was most noticeable when considering ITN coverage (odds ratio: 5.3, 95% CI: 3.67-7.70). This analysis provides key insights into the barriers of bed net ownership, which will help inform both LF and

Oral dirofilariasis.

PubMed

Janardhanan, Mahija; Rakesh, S; Savithri, Vindhya

2014-01-01

Filariasis affecting animals can rarely cause infections in human beings through the accidental bite of potential vectors. The resulting infection in man, known as zoonotic filariasis occur worldwide. Human dirofilariasis, the most common zoonotic filariasis, is caused by the filarial worm belonging to the genus Dirofilaria. Dirofilarial worms, which are recognized as pathogenic in man can cause nodular lesions in the lung, subcutaneous tissue, peritoneal cavity or eyes. Oral dirofilariasis is extremely rare and only a few cases have been documented. We report an interesting case of dirofilariasis due to Dirofilaria repens involving buccal mucosa in a patient who presented with a facial swelling. The clinical features, diagnostic issues and treatment aspects are discussed. This paper stresses the importance of considering dirofilariasis as differential diagnosis for subcutaneous swelling of the face, especially in areas where it is endemic.

Entomology with the U.S. Marines in Vietnam - Some Lessons Learned

DTIC Science & Technology

2008-11-16

these areas, and capability of individual commands. malaria, dengue, encephalitis, plague, This included the provision of scrub typhus and filariasis...any, probably due to the large, mobile was not available at the time. About 22 parasite reservoir (NVA, VC & local cases of scrub typhus occurred in...of light traps was November in Danang. often a challenge. Their use in the Filariasis, Scrub Typhus & Plague. "bush" was not feasible for security

Community level morbidity control of lymphoedema using self care and integrative treatment in two lymphatic filariasis endemic districts of South India: a non randomized interventional study.

PubMed

Narahari, Saravu R; Bose, Kuthaje S; Aggithaya, Madhur G; Swamy, Gaddam Kumara; Ryan, Terence J; Unnikrishnan, Bhaskaran; Washington, Reynold G; Rao, Balu Palicheralu Sreenivasa; Rajagopala, Shrikrishna; Manjula, Kadengodlu; Vandana, Usha; Sreemol, Thaivalath Anandan; Rojith, Mathew; Salimani, Shanappa Y; Shefuvan, Mohammed

2013-09-01

Currently there is no global program to manage lymphoedema as a result of lymphatic filariasis (LF). The primary aim of this study was to determine the efficacy of a previously proposed integrative treatment protocol, using locally available resources to address the morbidity, in a community village setting. Two LF endemic districts of south India, Gulbarga in Karnataka (GK) and Alleppey in Kerala (AK), were selected for the study. All known patients were invited to an LF camp. Patients with grade two late or three lymphoedema were enrolled. All patients were given training in the integrative procedure which involved patient education and the domiciliary protocol. A total of 730 patients (851 limbs) completed the three and half month follow up. There was a statistically significant (1%) reduction up to mid thigh level volume measurement for both small (0.7-1.1 liters) and large (1.8-5.0 liters) limbs, p < 0.000. In AK inflammatory episodes at the three months interval reduced from 37.5% (127 patients) to 28.3% (96 patients) and in GK from 37.6% (147 patients) to 10.2% (40 patients), p < 0.000. All patients had reduced bacterial entry points. There was an overall improvement in quality of life in all domains of LF specific quality of life questionnaire p < 0.000. Self care and integrative treatment is possible in resource poor Indian village settings. Further work is needed to explore factors leading to better compliance by randomizing the interventions such as washing and emollient compression vs Ayurvedic and yoga interventions before integrative treatment is considered for national health programmes in developing countries.

Detecting and confirming residual hotspots of lymphatic filariasis transmission in American Samoa 8 years after stopping mass drug administration.

PubMed

Lau, Colleen L; Sheridan, Sarah; Ryan, Stephanie; Roineau, Maureen; Andreosso, Athena; Fuimaono, Saipale; Tufa, Joseph; Graves, Patricia M

2017-09-01

The Global Programme to Eliminate Lymphatic Filariasis (LF) aims to eliminate the disease as a public health problem by 2020 by conducting mass drug administration (MDA) and controlling morbidity. Once elimination targets have been reached, surveillance is critical for ensuring that programmatic gains are sustained, and challenges include timely identification of residual areas of transmission. WHO guidelines encourage cost-efficient surveillance, such as integration with other population-based surveys. In American Samoa, where LF is caused by Wuchereria bancrofti, and Aedes polynesiensis is the main vector, the LF elimination program has made significant progress. Seven rounds of MDA (albendazole and diethycarbamazine) were completed from 2000 to 2006, and Transmission Assessment Surveys were passed in 2010/2011 and 2015. However, a seroprevalence study using an adult serum bank collected in 2010 detected two potential residual foci of transmission, with Og4C3 antigen (Ag) prevalence of 30.8% and 15.6%. We conducted a follow up study in 2014 to verify if transmission was truly occurring by comparing seroprevalence between residents of suspected hotspots and residents of other villages. In adults from non-hotspot villages (N = 602), seroprevalence of Ag (ICT or Og4C3), Bm14 antibody (Ab) and Wb123 Ab were 1.2% (95% CI 0.6-2.6%), 9.6% (95% CI 7.5%-12.3%), and 10.5% (95% CI 7.6-14.3%), respectively. Comparatively, adult residents of Fagali'i (N = 38) had significantly higher seroprevalence of Ag (26.9%, 95% CI 17.3-39.4%), Bm14 Ab (43.4%, 95% CI 32.4-55.0%), and Wb123 Ab 55.2% (95% CI 39.6-69.8%). Adult residents of Ili'ili/Vaitogi/Futiga (N = 113) also had higher prevalence of Ag and Ab, but differences were not statistically significant. The presence of transmission was demonstrated by 1.1% Ag prevalence (95% CI 0.2% to 3.1%) in 283 children aged 7-13 years who lived in one of the suspected hotspots; and microfilaraemia in four individuals, all of whom lived in the

Larvicidal and repellent activity of medicinal plant extracts from Eastern Ghats of South India against malaria and filariasis vectors.

PubMed

Kamaraj, Chinnaperumal; Rahuman, Abdul Abdul; Bagavan, Asokan; Elango, Gandhi; Zahir, Abdul Abduz; Santhoshkumar, Thirunavukkarasu

2011-09-01

To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna (A. concinna), Cassia siamea (C. siamea), Coriandrum sativum (C. sativum),Cuminum cyminum (C. cyminum), Lantana camara (L. camara), Nelumbo nucifera (N. nucifera) Phyllanthus amarus (P. amarus), Piper nigrum (P. nigrum) and Trachyspermum ammi (T. ammi) against Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus). The larvicidal activity of medicinal plant extracts were tested against early fourth-instar larvae of malaria and filariasis vectors. The mortality was observed 24 h and 48 h after treatment, data were subjected to probit analysis to determine the lethal concentrations (LC(50) and LC(90)) to kill 50 and 90 per cent of the treated larvae of the tested species. The repellent efficacy was determined against two mosquito species at five concentrations (31.25, 62.50, 125.00, 250.00, and 500.00 ppm) under the laboratory conditions. All plant extracts showed moderate effects after 24 h and 48 h of exposure; however, the highest activity was observed after 24 h in the leaf methanol extract of N. nucifera, seed ethyl acetate and methanol extract of P. nigrum against the larvae of An. stephensi (LC(50) = 34.76, 24.54 and 30.20 ppm) and against Cx. quinquefasciatus (LC(50) = 37.49, 43.94 and 57.39 ppm), respectively. The toxic effect of leaf methanol extract of C. siamea, seed methanol extract of C. cyminum, leaf ethyl acetate extract of N. nucifera, leaf ethyl acetate and methanol extract of P. amarus and seed methanol extract of T. ammi were showed 100% mortality against An. stephensi and Cx. quinquefasciatus after 48 h exposer. The maximum repellent activity was observed at 500 ppm in methanol extracts of N. nucifera, ethyl acetate and methanol extract of P. nigrum and methanol extract of T. ammi and the mean complete protection time ranged from 30 to 150 min with the different extracts tested. These results suggest that

The Impact of Lymphatic Filariasis Mass Drug Administration Scaling Down on Soil-Transmitted Helminth Control in School-Age Children. Present Situation and Expected Impact from 2016 to 2020.

PubMed

Mupfasoni, Denise; Montresor, Antonio; Mikhailov, Alexei; King, Jonathan

2016-12-01

Lymphatic filariasis (LF) and soil-transmitted-helminths (STH) are co-endemic in 58 countries which are mostly in Africa and Asia. Worldwide, 486 million school-age children are considered at risk of both diseases. In 2000, the World Health Organization (WHO) established the global programme to eliminate LF by 2020. Since then, the LF elimination programme has distributed ivermectin or diethylcarbamazine citrate (DEC) in combination with albendazole, thereby also treating STH. Consequently, many school-age children have been treated for STH through the LF programme. As treatment targets towards the 2020 LF elimination goal are achieved, many countries are implementing the transmission assessment survey (TAS) and, if the LF prevalence is estimated to be less than 1%, scaling down mass drug administration (MDA). We analysed the 2014 data on preventive chemotherapy (PC) reported from LF STH co-endemic countries and projected the year and location of TAS expected to be conducted between 2016 and 2020 to assess the impact of this scaling down on STH PC. Eighty percent of all co-endemic countries that have already stopped LF MDA nationally were able to establish STH PC through schools. It is estimated that 14% of the total number of children presently covered by the LF programme is at risk of not continuing to receive PC for STH. In order to achieve and maintain the WHO 2020 goal for STH control, there is an urgent need to establish and reinforce school-based deworming programmes in countries scaling-down national LF elimination programmes.

Efficacy and tolerability of treatment with single doses of diethylcarbamazine (DEC) and DEC plus albendazole (ABZ) for three consecutive years in lymphatic filariasis: a field study in India.

PubMed

Kshirsagar, Nilima A; Gogtay, N J; Garg, B S; Deshmukh, P R; Rajgor, D D; Kadam, V S; Thakur, P A; Gupta, A; Ingole, N S; Lazdins-Helds, J K

2017-10-01

Lymphatic filariasis (LF) affects 73 countries, causes morbidity and impedes socioeconomic development. We had found no difference in safety and micro (Mf) and macro filarial action of single-dose diethylcarbamazine (DEC) and DEC + albendazole (ABZ) in an F01 study done in India (year 2000). There was a programmatic need to evaluate safety and efficacy of multiple annual treatments (F02). Subjects (155) from the F01 study, meeting inclusion-exclusion criteria, were enrolled in F02 and treated with further two annual doses of DEC or DEC + ABZ. Efficacy was evaluated for Mf positivity by peripheral smear (PS) and nucleopore (NP) filter, circulating filarial antigen (CFA) and filarial dance sign (FDS) positivity and Mf count at yearly follow-up. Safety was assessed for 5 days after drug administration. Total of 139 subjects evaluated for efficacy (69 DEC and 70 DEC + ABZ group). Mf positivity prevalence declined progressively by 95% (PS), 66% (NP), and 95% (PS) and 86% (NP); CFA positivity prevalence declined by 15% and 9%; FDS by 100% each; Mf count declined by 75.5 and 76.9% with three annual treatment of DEC and DEC + ABZ, respectively. Addition of ABZ did not show any advantage over DEC given as three annual rounds for LF. DEC and DEC + ABZ were well tolerated. There was no correlation between result of CFA and FDS, (both claimed to be indicative of adult worm). Analysis of published studies and our data indicate that macrofilaricidal effect of DEC/DEC + ABZ may be seen in children and not adults, with three or more annual dosing.

Use of Remote Sensing Surveillance to Monitor Environmental Parameters Associated with Mosquito Abundance and Vector-borne Diseases

NASA Technical Reports Server (NTRS)

1996-01-01

Lymphatic filariasis persists as a major cause of clinical morbidity and a significant impediment to socioeconomic development in various parts of the world including Egypt. In Egypt, filariasis has been endemic since time immemorial. Early epidemiologic studies identified Culex pipiens L. as the main vector of the disease and also showed that the geographic distribution of the disease is highly focal and concentrated in lower Egypt. Between 1950 and 1965, a large scale filariasis control program was carried out by the Egyptian Ministry of Health (EMOH) in the endemic areas. Control efforts led to a steady decrease of the disease in areas of the country previously identified as endemic. However, spot surveys conducted in various parts of the Nile Delta during the 1970's and 1980's revealed that the downward trend of the disease had stopped and that the prevalence and intensity of microfilaraemia had increased.

Community-based field implementation scenarios of a short message service reporting tool for lymphatic filariasis case estimates in Africa and Asia.

PubMed

Mableson, Hayley E; Martindale, Sarah; Stanton, Michelle C; Mackenzie, Charles; Kelly-Hope, Louise A

2017-01-01

Lymphatic filariasis (LF) is a neglected tropical disease (NTD) targeted for global elimination by 2020. Currently there is considerable international effort to scale-up morbidity management activities in endemic countries, however there remains a need for rapid, cost-effective methods and adaptable tools for obtaining estimates of people presenting with clinical manifestations of LF, namely lymphoedema and hydrocele. The mHealth tool ' MeasureSMS-Morbidity ' allows health workers in endemic areas to use their own mobile phones to send clinical information in a simple format using short message service (SMS). The experience gained through programmatic use of the tool in five endemic countries across a diversity of settings in Africa and Asia is used here to present implementation scenarios that are suitable for adapting the tool for use in a range of different programmatic, endemic, demographic and health system settings. A checklist of five key factors and sub-questions was used to determine and define specific community-based field implementation scenarios for using the MeasureSMS-Morbidity tool in a range of settings. These factors included: (I) tool feasibility (acceptability; community access and ownership); (II) LF endemicity (high; low prevalence); (III) population demography (urban; rural); (IV) health system structure (human resources; community access); and (V) integration with other diseases (co-endemicity). Based on experiences in Bangladesh, Ethiopia, Malawi, Nepal and Tanzania, four implementation scenarios were identified as suitable for using the MeasureSMS-Morbidity tool for searching and reporting LF clinical case data across a range of programmatic, endemic, demographic and health system settings. These include: (I) urban, high endemic setting with two-tier reporting; (II) rural, high endemic setting with one-tier reporting; (III) rural, high endemic setting with two-tier reporting; and (IV) low-endemic, urban and rural setting with one

Studies of Anopheles gambiae s.l (Diptera: Culicidae) exhibiting different vectorial capacities in lymphatic filariasis transmission in the Gomoa district, Ghana.

PubMed

Amuzu, Hilaria; Wilson, Michael D; Boakye, Daniel A

2010-09-14

Two lymphatic filariasis endemic communities Mampong and Hwida in Ghana have been regularly monitored for impact on transmission after annual mass drug administration (MDA) with albendazole and ivermectin. After six MDAs even though the ABR for Mampong was 55883/person/year and that of Hwida was 2494/person/year, they both had ATPs of 15.21 infective larvae/person/year. Interestingly the human microfilaraemia levels had reduced significantly from 14% to 0% at Mampong and 12% to 3% at Hwida. In an attempt to understand this anomaly, we collected mosquitoes over a 5-month period using human landing catches to determine the species composition, the number of cibarial teeth, the lengths and widths of the cibarium and the cibarial dome of the vector populations. Out of 2553 mosquitoes caught at Mampong, 42.6% were An. gambiae s.l. All 280 identified further by PCR were An. gambiae s.s (275 M and 5 S molecular forms). At Hwida, 112 mosquitoes were obtained; 67 (59.8%) were An. gambiae s.l, comprised of 40 (59.7%) An. melas, 24 (35.8%) An. gambiae s.s (17 and 5 M and S molecular forms respectively) and 3 (4.5%) unidentified. The mean number of teeth for An. melas was 14.1 (median = 14, range = 12-15), An. gambiae s.s., 15.7 (median = 15, range = 13-19) M form 15.5 (median = 15 range = 13-19) and S form 16 (median = 16, range 15-17). The observed differences in teeth numbers were significantly different between An. melas and An. gambiae s.s (p = 0.004), and the M form (p = 0.032) and the S form (p = 0.002). In this study, An. gambiae s.s was the main vector at Mampong and was found to possess significantly more cibarial teeth than An. melas, the principal vector at Hwida. We postulate that the different impact observed after 6 MDAs may be due to An. gambiae s.s exhibiting 'facilitation' at Mampong and at Hwida An. melas the main vector exhibits 'limitation'. Thus it may be necessary to compliment MDA with vector control to achieve interruption of transmission in areas

Is mass drug administration against lymphatic filariasis required in urban settings? The experience in Kano, Nigeria.

PubMed

Pam, Dung D; de Souza, Dziedzom K; D'Souza, Susan; Opoku, Millicent; Sanda, Safiya; Nazaradden, Ibrahim; Anagbogu, Ifeoma N; Okoronkwo, Chukwu; Davies, Emmanuel; Elhassan, Elisabeth; Molyneux, David H; Bockarie, Moses J; Koudou, Benjamin G

2017-10-01

The Global Programme to Eliminate Lymphatic Filariasis (GPELF), launched in 2000, has the target of eliminating the disease as a public health problem by the year 2020. The strategy adopted is mass drug administration (MDA) to all eligible individuals in endemic communities and the implementation of measures to reduce the morbidity of those suffering from chronic disease. Success has been recorded in many rural endemic communities in which elimination efforts have centered. However, implementation has been challenging in several urban African cities. The large cities of West Africa, exemplified in Nigeria in Kano are challenging for LF elimination program because reaching 65% therapeutic coverage during MDA is difficult. There is therefore a need to define a strategy which could complement MDA. Thus, in Kano State, Nigeria, while LF MDA had reached 33 of the 44 Local Government Areas (LGAs) there remained eleven 'urban' LGAs which had not been covered by MDA. Given the challenges of achieving at least 65% coverage during MDA implementation over several years in order to achieve elimination, it may be challenging to eliminate LF in such settings. In order to plan the LF control activities, this study was undertaken to confirm the LF infection prevalence in the human and mosquito populations in three urban LGAs. The prevalence of circulating filarial antigen (CFA) of Wuchereria bancrofti was assessed by an immuno-chromatography test (ICT) in 981 people in three urban LGAs of Kano state, Nigeria. Mosquitoes were collected over a period of 4 months from May to August 2015 using exit traps, gravid traps and pyrethrum knock-down spray sheet collections (PSC) in different households. A proportion of mosquitoes were analyzed for W. bancrofti, using dissection, loop-mediated isothermal amplification (LAMP) assay and conventional polymerase chain reaction (PCR). The results showed that none of the 981 subjects (constituted of <21% of children 5-10 years old) tested had

Vulval Elephantiasis: A Case Report

PubMed Central

Mohan, Harsh; Bisht, Bhumika; Goel, Poonam; Garg, Geeta

2012-01-01

Introduction. Elephantiasis is a chronic manifestation of filariasis; it commonly affects limbs, scrotum, and trunk. Females have lower incidence of filarial infection. Vulval elephantiasis due to filariasis is still rarer. It is difficult to make the diagnosis on histopathology alone, more so in view of the fact that the parasite is usually not identified in tissue sections. Identification of microfilariae in night samples of peripheral blood or seropositivity for filarial antigen is requisite for the correct diagnosis. Case Presentation. A young female presented with progressively increasing vulval swelling over a period of two years. The swelling was soft and measured 5 × 6 cm. Other possible differential diagnoses were excluded, and ancillary tests were performed to reach a conclusive diagnosis of vulval elephantiasis on histopathology. Conclusion. Vulval elephantiasis due to filariasis is rare. Its diagnosis on histopathology is more often by exclusion. High index of suspicion on microscopic findings and corelation with relevant diagnostic tests are required to reach the correct diagnosis. PMID:23198192

The role of personal opinions and experiences in compliance with mass drug administration for lymphatic filariasis elimination in Kenya.

PubMed

Njomo, Doris W; Amuyunzu-Nyamongo, Mary; Magambo, Japheth K; Njenga, Sammy M

2012-01-01

The main strategy adopted for Lymphatic Filariasis (LF) elimination globally is annual mass drug administration (MDA) for 4 to 6 rounds. At least 65% of the population at risk should be treated in each round for LF elimination to occur. In Kenya, MDA using diethylcarbamazine citrate (DEC) and albendazole data shows declining compliance (proportion of eligible populations who receive and swallow the drugs) levels (85%-62.8%). The present study's aim was to determine the role of personal opinions and experiences in compliance with MDA. This was a retrospective cross-sectional study conducted between January and September 2009 in two districts based on December 2008 MDA round. In each district, one location with high and one with low compliance was selected. Through systematic sampling, nine villages were selected and interviewer-based questionnaires administered to 965 household heads or adult representatives also systematically sampled. The qualitative data were generated from opinion leaders, LF patients with clinical signs and community drug distributors (CDDs) all purposively selected and interviewed. Sixteen focus group discussions (FGDs) were also conducted with single-sex adult and youth male and female groups. Chi square test was used to assess the statistical significance of differences in compliance with treatment based on the records reviewed. The house-to-house method of drug distribution influenced compliance. Over one-quarter (27%) in low compared to 15% in high compliance villages disliked this method. Problems related to size, number and taste of the drugs were more common in low (16.4%) than in high (14.4%) compliance villages. Reasons for failure to take the drugs were associated with compliance (p<0.001). The reasons given included: feeling that the drugs were not necessary, CDD not visiting to issue the drugs, being absent and thinking that the drugs were meant for only the patients with LF clinical signs. A dislike for modern medicine prevailed

Parasite-Antigen Driven Expansion of IL-5− and IL-5+ Th2 Human Subpopulations in Lymphatic Filariasis and Their Differential Dependence on IL-10 and TGFβ

PubMed Central

Anuradha, Rajamanickam; George, Parakkal Jovvian; Hanna, Luke E.; Chandrasekaran, Vedachalam; Kumaran, P. Paul; Nutman, Thomas B.; Babu, Subash

2014-01-01

Background Two different Th2 subsets have been defined recently on the basis of IL-5 expression – an IL-5+Th2 subset and an IL-5−Th2 subset in the setting of allergy. However, the role of these newly described CD4+ T cells subpopulations has not been explored in other contexts. Methods To study the role of the Th2 subpopulation in a chronic, tissue invasive parasitic infection (lymphatic filariasis), we examined the frequency of IL-5+IL-4+IL-13+ CD4+ T cells and IL-5−IL-4 IL-13+ CD4+ T cells in asymptomatic, infected individuals (INF) and compared them to frequencies (Fo) in filarial-uninfected (UN) individuals and to those with filarial lymphedema (CP). Results INF individuals exhibited a significant increase in the spontaneously expressed and antigen-induced Fo of both Th2 subpopulations compared to the UN and CP. Interestingly, there was a positive correlation between the Fo of IL-5+Th2 cells and the absolute eosinophil and neutrophil counts; in addition there was a positive correlation between the frequency of the CD4+IL-5−Th2 subpopulation and the levels of parasite antigen – specific IgE and IgG4 in INF individuals. Moreover, blockade of IL-10 and/or TGFβ demonstrated that each of these 2 regulatory cytokines exert opposite effects on the different Th2 subsets. Finally, in those INF individuals cured of infection by anti-filarial therapy, there was a significantly decreased Fo of both Th2 subsets. Conclusions Our findings suggest that both IL-5+ and IL-5−Th2 cells play an important role in the regulation of immune responses in filarial infection and that these two Th2 subpopulations may be regulated by different cytokine-receptor mediated processes. PMID:24498448

Rapid community identification, pain and distress associated with lymphoedema and adenolymphangitis due to lymphatic filariasis in resource-limited communities of North-eastern Nigeria.

PubMed

Akogun, O B; Akogun, M K; Apake, E; Kale, O O

2011-09-01

Identification of communities with people that could benefit from adenolymphangitis (ADL) and lymphoedema morbidity management within Lymphatic Filariasis Elimination Programmes (NLFEP) in many African countries is a major challenge to programme managers. Another challenge is advocating for proportionate allocation of funds to alleviating the suffering that afflicted people bear. In this study we developed a rapid qualitative technique of identifying communities where morbidity management programme could be situated and documenting the pain and distress that afflicted persons endure. Estimates given by health personnel and by community resource persons were compared with systematic household surveys for the number of persons with lymphoedema of the lower limb. Communities in Northeastern Nigeria, with the largest number of lymphoedema cases were selected and a study of local knowledge, physical, psychosocial burden and intervention-seeking activities associated with the disease documented using an array of techniques (including household surveys, key informant interviews, group discussions and informal conversations). Health personnel gave a more accurate estimate of the number of lymphoedema patients in their communities than either the community leader or the community directed ivermectin distributor (CDD). Community members with lymphoedema preferred to confide in health personnel from other communities. The people had a well developed local vocabulary for lymphoedema and are well aware of the indigenous transmission theories. Although the people associated the episodic ADL attacks with the rains which were more frequent at that period they did not associate the episodes with gross lymphoedema. There were diverse theories about lymphoedema causation with heredity, accidental stepping on charmed objects and organisms, breaking taboos. The most popular belief about causation, however, is witchcraft (60.9%). The episodic attacks are dreaded by the afflicted, since

"Filarial dance sign" real-time ultrasound diagnosis of filarial oophoritis.

PubMed

Panditi, Surekha; Shelke, Ashwini G; Thummalakunta, Laxmi Narasimha Praveen

2016-10-01

Filariasis is a parasitic disease caused by Filarial nematodes (Wuchereria bancrofti, Brugia malayi, and Brugia timori) that commonly causes lymphatic obstruction resulting in edema and increase in the size of the affected organ. Filariasis is diagnosed by identifying microfilariae on Giemsa stain. The immunochromatographic card test is diagnostic. Ultrasound is the imaging modality of choice for detecting adult filarial worms/microfilaria in the lymphatic system, which are responsible for the classic "filarial dance sign" caused by twirling movements of the microfilariae. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:500-501, 2016. © 2016 Wiley Periodicals, Inc.

Developing a community-led SMS reporting tool for the rapid assessment of lymphatic filariasis morbidity burden: case studies from Malawi and Ghana.

PubMed

Stanton, Michelle C; Mkwanda, Square Z; Debrah, Alexander Y; Batsa, Linda; Biritwum, Nana-Kwadwo; Hoerauf, Achim; Cliffe, Matthew; Best, Abigail; Molineux, Andrew; Kelly-Hope, Louise A

2015-05-16

Lymphoedema and hydrocoele are the two most common clinical manifestations of lymphatic filariasis (LF). In order to effectively target morbidity management strategies, more information is rapidly needed on morbidity burden across all endemic countries. The purpose of this study was to develop and test an SMS tool (MeasureSMS) which enables trained community-based health workers to report basic information on all cases they identified. The tool was trialled in Chikwawa district, Malawi and Ahanta West district, Ghana in 2014. Salaried health surveillance assistants (HSAs) identified and reported cases in Malawi whereas volunteer community health workers (CHWs) were used in Ghana. Health workers were trained in recognising lymphoedema and hydrocoeles and submitting individual case data using MeasureSMS, after which they undertook a LF morbidity survey. After the reporting period, a random sample of reported cases was visited by a physician to verify the health workers' diagnoses. The proportion of correctly diagnosed cases i.e. the positive predictive value (PPV) was then calculated. HSAs in Malawi successfully reported 256 unique cases by SMS from 107 communities (166 hydrocoele, 88 lymphoedema, 2 with both), resulting in an estimated adult prevalence of 17.7 per 10,000 and 33.0 per 10,000 for lymphoedema and hydrocoele respectively. In Ghana, despite being less experienced in using SMS, CHWs successfully reported 360 unique cases by SMS from 33 communities (169 hydrocoele, 185 lymphoedema, 6 with both), resulting in an estimated adult prevalence of 76.9 per 10,000 and 70.5 per 10,000 adults for lymphoedema and hydrocoele respectively. The verification exercise resulted in a PPV for lymphoedema and hydrocoele diagnosis of 90 % (n = 42, 95 % CI 76.5 - 96.9) and 92 % (n = 49, 95 % CI 79.5 - 97.4) in Malawi and 94 % (n = 34, 95 % CI 78.9 %-99.0 %) and 47 % (n = 59, 35.1 %-61.7 %) in Ghana, indicating that non-invasive methods for diagnosing hydrocoeles needed to be

Brugia Rapid™ antibody responses in communities of Indonesia in relation to the results of 'transmission assessment surveys' (TAS) for the lymphatic filariasis elimination program.

PubMed

Dewi, Rita M; Tuti, Sekar; Ganefa, Sitti; Anwar, Chairiyah; Larasati, Ria; Ariyanti, Endah; Herjati, Herty; Brady, Molly

2015-10-01

The Global Programme to Eliminate Lymphatic Filariasis recommends the transmission assessment survey (TAS) as the preferred methodology for determining whether mass drug administration can be stopped in an endemic area. Because of the limited experience available globally with the use of Brugia Rapid™ tests in conducting TAS in Brugia spp. areas, we explored the relationship between the antibody test results and Brugia spp. infection as detected by microfilaremia in different epidemiological settings. The study analyzes the Brugia Rapid™ antibody responses and microfilaremia in all ages at three study sites in: i) a district which was classified as non-endemic, ii) a district which passed TAS, and iii) a district which failed TAS. Convenience sampling was done in each site, in one to three purposefully selected villages with a goal of 500 samples in each district. A total of 1543 samples were collected from residents in all three study sites. In the site which was classified as non-endemic and where MDA had not been conducted, 5 % of study participants were antibody positive, none was positive for microfilaremia, and age-specific antibody prevalence peaked at almost 8 % in the 25-34 year-old age range, with no antibody-positive results found in children under eight years of age. In the site that had passed TAS, 1 % of participants were antibody positive and none was positive for microfilaremia. In the site which failed TAS, 15 % of participants were antibody positive, 0.2 % were microfilaremic, and age-specific antibody prevalence was highest in 6-7 year olds (30 %), but above 8 % in all age levels above 8 years old. These results from districts which followed the current WHO guidance for mapping, MDA, and implementing TAS, while providing antibody profiles of treated and untreated populations under programmatic settings, support the choice of antibody prevalence in the 6- and 7-year-old age group in TAS for making stopping MDA decisions. Since only one study

Impact of two rounds of mass treatment with diethylcarbamazine plus albendazole on Wuchereria bancrofti infection and the sensitivity of immunochromatographic test in Malindi, Kenya.

PubMed

Njenga, S M; Wamae, C N; Njomo, D W; Mwandawiro, C S; Molyneux, D H

2008-10-01

Annual single-dose mass treatment of endemic populations with a combination of either diethylcarbamazine (DEC) or ivermectin plus albendazole is recommended as the mainstay of lymphatic filariasis elimination programmes. We evaluated the impact of two rounds of annual mass drug administration (MDA) of DEC and albendazole on bancroftian filariasis in a pilot elimination programme in an endemic area of Kenya. Overall prevalence of microfilaraemia decreased by 65.4%, whereas community microfilarial load decreased by 84% after the two MDAs. The prevalence of parasite antigenaemia determined by immunochromatographic test (ICT) declined significantly by 43.5% after the two MDAs. We also studied the effect of mass treatment on the sensitivity of the ICT. Although the sensitivity of the test before treatment was high (89.9%; kappa=0.909) sensitivity was lower after two MDAs (59.3%; kappa=0.644). The finding raises concern about the reliability of the ICT in long-term monitoring of infection and for establishing programmatic endpoints. The results of the present study indicate a relatively high effectiveness of MDA using a DEC/albendazole combination against Wuchereria bancrofti infection and, therefore, it may be a useful strategy to eliminate lymphatic filariasis in onchocerciasis-free areas.

Continental-scale, data-driven predictive assessment of eliminating the vector-borne disease, lymphatic filariasis, in sub-Saharan Africa by 2020.

PubMed

Michael, Edwin; Singh, Brajendra K; Mayala, Benjamin K; Smith, Morgan E; Hampton, Scott; Nabrzyski, Jaroslaw

2017-09-27

There are growing demands for predicting the prospects of achieving the global elimination of neglected tropical diseases as a result of the institution of large-scale nation-wide intervention programs by the WHO-set target year of 2020. Such predictions will be uncertain due to the impacts that spatial heterogeneity and scaling effects will have on parasite transmission processes, which will introduce significant aggregation errors into any attempt aiming to predict the outcomes of interventions at the broader spatial levels relevant to policy making. We describe a modeling platform that addresses this problem of upscaling from local settings to facilitate predictions at regional levels by the discovery and use of locality-specific transmission models, and we illustrate the utility of using this approach to evaluate the prospects for eliminating the vector-borne disease, lymphatic filariasis (LF), in sub-Saharan Africa by the WHO target year of 2020 using currently applied or newly proposed intervention strategies. METHODS AND RESULTS: We show how a computational platform that couples site-specific data discovery with model fitting and calibration can allow both learning of local LF transmission models and simulations of the impact of interventions that take a fuller account of the fine-scale heterogeneous transmission of this parasitic disease within endemic countries. We highlight how such a spatially hierarchical modeling tool that incorporates actual data regarding the roll-out of national drug treatment programs and spatial variability in infection patterns into the modeling process can produce more realistic predictions of timelines to LF elimination at coarse spatial scales, ranging from district to country to continental levels. Our results show that when locally applicable extinction thresholds are used, only three countries are likely to meet the goal of LF elimination by 2020 using currently applied mass drug treatments, and that switching to more

Acute larvicidal toxicity of five essential oils (Pinus nigra, Hyssopus officinalis, Satureja montana, Aloysia citrodora and Pelargonium graveolens) against the filariasis vector Culex quinquefasciatus: Synergistic and antagonistic effects.

PubMed

Benelli, Giovanni; Pavela, Roman; Canale, Angelo; Cianfaglione, Kevin; Ciaschetti, Giampiero; Conti, Fabio; Nicoletti, Marcello; Senthil-Nathan, Sengottayan; Mehlhorn, Heinz; Maggi, Filippo

2017-04-01

Mosquito vector control is facing a number of important and timely challenges, mainly due to the rapid development of pesticide resistance and environmental concerns. In this scenario, screening of botanical resources for their mosquitocidal activity may offer effective and eco-friendly tools against Culicidae vectors. Culex quinquefasciatus Say (Diptera: Culicidae) is a vector of lymphatic filariasis and of dangerous arboviral diseases, such as West Nile and St. Louis encephalitis. In this study, the chemical composition of five essential oils obtained from different plants, namely Pinus nigra J.F. Arnold var. italica (Pinaceae), Hyssopus officinalis L. subsp. aristatus (Lamiaceae), Satureja montana L. subsp. montana (Lamiaceae), Aloysia citriodora Palau (Verbenaceae) and Pelargonium graveolens L'Hér (Geraniaceae), was investigated by GC-MS analysis. Furthermore, it was evaluated their acute toxicity on larvae of C. quinquefasciatus. Then, the most effective oils were selected, in order to focus on the potential synergistic and antagonistic effects, testing them in binary mixtures on C. quinquefasciatus larvae. Results showed that the higher effectiveness was obtained by S. montana subsp. montana essential oil (LC 50 =25.6μL·L -1 ), followed by P. nigra var. italica (LC 50 =49.8μL·L -1 ) and A. citriodora (LC 50 =65.6μL·L -1 ), while the other essential oils showed LC 50 values higher than 90μL·L -1 . The larvicidal effectiveness can be enhanced by preparing simple binary mixtures of essential oils, such as S. montana+A. citriodora (ratio 1:1), which showed higher larvicidal toxicity (LC 50 =18.3μL·L -1 ). On the other hand, testing S. montana+P. nigra (1:1) an antagonistic effect was detected, leading to a LC 50 (72.5μL·L -1 ) higher than the LC 50 values calculated for the two oils tested separately. Overall, our results add useful knowledge to allow the employ of synergistic essential oil blends as effective, cheap and eco-friendly mosquito

Pulmonary Manifestations in Filariasis.

DTIC Science & Technology

1977-07-15

enlarged epididimis. Elephantiasis of lower limbs occurred in 1.15% of the cases while lymphatic edema of the lower limbs occurred in 6.84% of the cases. The...prevalence of filaraemia and elephantiasis in the young age group age group indicates active transmission. In a comparison of the thick smear method

Multiple Resistances and Complex Mechanisms of Anopheles sinensis Mosquito: A Major Obstacle to Mosquito-Borne Diseases Control and Elimination in China

PubMed Central

Fang, Qiang; Hartsel, Joshua; Zhou, Guofa; Shi, Linna; Fang, Fujin; Zhu, Changliang; Yan, Guiyun

2014-01-01

Malaria, dengue fever, and filariasis are three of the most common mosquito-borne diseases worldwide. Malaria and lymphatic filariasis can occur as concomitant human infections while also sharing common mosquito vectors. The overall prevalence and health significance of malaria and filariasis have made them top priorities for global elimination and control programmes. Pyrethroid resistance in anopheline mosquito vectors represents a highly significant problem to malaria control worldwide. Several methods have been proposed to mitigate insecticide resistance, including rotational use of insecticides with different modes of action. Anopheles sinensis, an important malaria and filariasis vector in Southeast Asia, represents an interesting mosquito species for examining the consequences of long-term insecticide rotation use on resistance. We examined insecticide resistance in two An. Sinensis populations from central and southern China against pyrethroids, organochlorines, organophosphates, and carbamates, which are the major classes of insecticides recommended for indoor residual spray. We found that the mosquito populations were highly resistant to the four classes of insecticides. High frequency of kdr mutation was revealed in the central population, whereas no kdr mutation was detected in the southern population. The frequency of G119S mutation in the ace-1 gene was moderate in both populations. The classification and regression trees (CART) statistical analysis found that metabolic detoxification was the most important resistance mechanism, whereas target site insensitivity of L1014 kdr mutation played a less important role. Our results indicate that metabolic detoxification was the dominant mechanism of resistance compared to target site insensitivity, and suggests that long-term rotational use of various insecticides has led An. sinensis to evolve a high insecticide resistance. This study highlights the complex network of mechanisms conferring multiple

Elimination and eradication of neglected tropical diseases with mass drug administrations: a survey of experts.

PubMed

Keenan, Jeremy D; Hotez, Peter J; Amza, Abdou; Stoller, Nicole E; Gaynor, Bruce D; Porco, Travis C; Lietman, Thomas M

2013-01-01

Lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths, and trachoma are the five most prevalent neglected tropical diseases in the world, and each is frequently treated with mass drug administrations. We performed a survey of neglected tropical diseases experts to elicit their opinions on the role of mass drug administrations for the elimination of these infections. We sent an online survey to corresponding authors who had published an article about a neglected tropical disease from 2007 to 2011. Of 825 unique authors who were invited to complete the survey, 365 (44.2%) responded, including 234 (28.4%) who answered questions regarding one of the five most prevalent neglected tropical diseases. Respondents had varying opinions about the goals of programmatic activities for their chosen neglected tropical disease, with elimination or eradication identified as the most important goal by 87% of lymphatic filariasis respondents, 66% of onchocerciasis respondents, 55% of trachoma respondents, 24% of schistosomiasis respondents, and 21% of soil-transmitted helminth respondents. Mass drug administrations, other non-medication health measures, and education were generally thought to be more important for elimination than vector control, development of a new tool, or the presence of a secular trend. Drug resistance was thought to be a major limitation of mass drug administrations for all five neglected tropical diseases. Over half of respondents for lymphatic filariasis and trachoma thought that repeated mass drug administrations could eliminate infection within ten years of the initiation of mass treatments. Respondents for lymphatic filariasis, onchocerciasis, and trachoma were more enthusiastic about the prospects of elimination and eradication than were respondents for schistosomiasis or soil-transmitted helminths. Mass drug administrations were generally believed to be among the most important factors for the success of elimination efforts

Successful Control of Soil-Transmitted Helminthiasis in School Age Children in Burkina Faso and an Example of Community-Based Assessment via Lymphatic Filariasis Transmission Assessment Survey.

PubMed

Drabo, François; Ouedraogo, Hamado; Bougma, Roland; Bougouma, Clarisse; Bamba, Issouf; Zongo, Dramane; Bagayan, Mohamed; Barrett, Laura; Yago-Wienne, Fanny; Palmer, Stephanie; Chu, Brian; Toubali, Emily; Zhang, Yaobi

2016-05-01

Burkina Faso is endemic with soil-transmitted helminth infections. Over a decade of preventive chemotherapy has been implemented through annual lymphatic filariasis (LF) mass drug administration (MDA) for population aged five years and over, biennial treatment of school age children with albendazole together with schistosomiasis MDA and biannual treatment of pre-school age children through Child Health Days. Assessments were conducted to evaluate the current situation and to determine the treatment strategy for the future. A cross-sectional assessment was conducted in 22 sentinel sites across the country in 2013. In total, 3,514 school age children (1,748 boys and 1,766 girls) were examined by the Kato-Katz method. Overall, soil-transmitted helminth prevalence was 1.3% (95% CI: 1.0-1.8%) in children examined. Hookworm was the main species detected, with prevalence of 1.2% (95% CI: 0.9-1.6%) and mean egg counts of 2.1 epg (95% CI: 0-4.2 epg). Among regions, the Centre Ouest region had the highest hookworm prevalence of 3.4% (95% CI: 1.9-6.1%) and mean egg counts of 14.9 epg (95% CI: 3.3-26.6 epg). A separate assessment was conducted in the Centre Nord region in 2014 using community-based cluster survey design during an LF transmission assessment survey (TAS). In this assessment, 351 children aged 6-7 years and 345 children aged 10-14 years were examined, with two cases (0.6% (95% CI: 0.2-2.1%)) and seven cases (2.0% (95% CI: 1.0-4.1%)) of hookworm infection was identified respectively. The results using both age groups categorized the region to be 2% to <10% in STH prevalence according to the pre-defined cut-off values. Through large-scale preventive chemotherapy, Burkina Faso has effectively controlled STH in school age children in the country. Research should be conducted on future strategies to consolidate the gain and to interrupt STH transmission in Burkina Faso. It is also demonstrated that LF TAS provides one feasible and efficient platform to assess the STH

Turbid white urine

PubMed Central

Vera, Manel; Molano, Alejandra; Rodríguez, Patricia

2010-01-01

Turbid white urine ‘albinuria’ is defined as a urine discoloration described as milky or cloudy. One of the most frequent causes of turbid white urine is chyluria complicating filariasis (Table 1). The extant causes of albinuria are non parasitic and rare. Amongst their aetiologies stand excessive mineral sediment excretion such as calciuria and phosphaturia, massive pyuria and fungal infections, and rarely congenital malformations of the lymphatic vessels. Malingering is also possible, in patients adding milk to their urine. We observed a case of albinuria in which the diagnostic work up led to diagnosing an exceptional cause of chyluria in a patient living in a region of Colombia where filariasis is not endemic. PMID:25949403

Multiplex serology for impact evaluation of bed net distribution on burden of lymphatic filariasis and four species of human malaria in northern Mozambique

PubMed Central

Candrinho, Baltazar; Chambe, Geraldo; Muchanga, João; Muguande, Olinda; Matsinhe, Graça; Mathe, Guidion; Rogier, Eric; Doyle, Timothy; Zulliger, Rose; Colborn, James; Saifodine, Abu; Lammie, Patrick; Priest, Jeffrey W.

2018-01-01

Background Universal coverage with long-lasting insecticidal nets (LLINs) is a primary control strategy against Plasmodium falciparum malaria. However, its impact on the three other main species of human malaria and lymphatic filariasis (LF), which share the same vectors in many co-endemic areas, is not as well characterized. The recent development of multiplex antibody detection provides the opportunity for simultaneous evaluation of the impact of control measures on the burden of multiple diseases. Methodology/Principal findings Two cross-sectional household surveys at baseline and one year after a LLIN distribution campaign were implemented in Mecubúri and Nacala-a-Velha Districts in Nampula Province, Mozambique. Both districts were known to be endemic for LF; both received mass drug administration (MDA) with antifilarial drugs during the evaluation period. Access to and use of LLINs was recorded, and household members were tested with P. falciparum rapid diagnostic tests (RDTs). Dried blood spots were collected and analyzed for presence of antibodies to three P. falciparum antigens, P. vivax MSP-119, P. ovale MSP-119, P. malariae MSP-119, and three LF antigens. Seroconversion rates were calculated and the association between LLIN use and post-campaign seropositivity was estimated using multivariate regression. The campaign covered 68% (95% CI: 58–77) of the population in Nacala-a-Velha and 46% (37–56) in Mecubúri. There was no statistically significant change in P. falciparum RDT positivity between the two surveys. Population seropositivity at baseline ranged from 31–81% for the P. falciparum antigens, 3–4% for P. vivax MSP-119, 41–43% for P. ovale MSP-119, 46–56% for P. malariae MSP-119, and 37–76% for the LF antigens. The seroconversion rate to the LF Bm33 antigen decreased significantly in both districts. The seroconversion rate to P. malariae MSP-119 and the LF Wb123 and Bm14 antigens each decreased significantly in one of the two districts

Multiplex serology for impact evaluation of bed net distribution on burden of lymphatic filariasis and four species of human malaria in northern Mozambique.

PubMed

Plucinski, Mateusz M; Candrinho, Baltazar; Chambe, Geraldo; Muchanga, João; Muguande, Olinda; Matsinhe, Graça; Mathe, Guidion; Rogier, Eric; Doyle, Timothy; Zulliger, Rose; Colborn, James; Saifodine, Abu; Lammie, Patrick; Priest, Jeffrey W

2018-02-01

Universal coverage with long-lasting insecticidal nets (LLINs) is a primary control strategy against Plasmodium falciparum malaria. However, its impact on the three other main species of human malaria and lymphatic filariasis (LF), which share the same vectors in many co-endemic areas, is not as well characterized. The recent development of multiplex antibody detection provides the opportunity for simultaneous evaluation of the impact of control measures on the burden of multiple diseases. Two cross-sectional household surveys at baseline and one year after a LLIN distribution campaign were implemented in Mecubúri and Nacala-a-Velha Districts in Nampula Province, Mozambique. Both districts were known to be endemic for LF; both received mass drug administration (MDA) with antifilarial drugs during the evaluation period. Access to and use of LLINs was recorded, and household members were tested with P. falciparum rapid diagnostic tests (RDTs). Dried blood spots were collected and analyzed for presence of antibodies to three P. falciparum antigens, P. vivax MSP-119, P. ovale MSP-119, P. malariae MSP-119, and three LF antigens. Seroconversion rates were calculated and the association between LLIN use and post-campaign seropositivity was estimated using multivariate regression. The campaign covered 68% (95% CI: 58-77) of the population in Nacala-a-Velha and 46% (37-56) in Mecubúri. There was no statistically significant change in P. falciparum RDT positivity between the two surveys. Population seropositivity at baseline ranged from 31-81% for the P. falciparum antigens, 3-4% for P. vivax MSP-119, 41-43% for P. ovale MSP-119, 46-56% for P. malariae MSP-119, and 37-76% for the LF antigens. The seroconversion rate to the LF Bm33 antigen decreased significantly in both districts. The seroconversion rate to P. malariae MSP-119 and the LF Wb123 and Bm14 antigens each decreased significantly in one of the two districts. Community LLIN use was associated with a decreased risk

Duration of detection of anti-BmR1 IgG4 antibodies after mass-drug administration (MDA) in Sarawak, Malaysia.

PubMed

Noordin, R; Muhi, J; Md Idris, Z; Arifin, N; Kiyu, A

2012-03-01

The detection rates of brugian filariasis in three regions of Sarawak namely Central, North and South after three courses of mass drug administration (MDA) from year 2004 to 2006 was investigated. A recombinant BmR1 antigen-based IgG4 detection test, named Brugia Rapid and night blood smear for microfilaria (mf) detection were used. All three regions recorded a sharp fall in mf positive rates after a year post-MDA. Meanwhile Brugia Rapid positive rates declined more gradually to 3.8% and 5.6% of the pre-MDA levels in the Central and North regions, respectively. This study showed that in filariasis endemic areas in Sarawak, anti-filarial IgG4 antibodies to BmR1, as detected by the Brugia Rapid test, were positive for one to two years after mf disappearance.

Evaluating Vaccine Candidates for Filariasis

DTIC Science & Technology

2013-04-16

rat mite (Ornithonyssus bacoti). The infective larvae migrate through the host dermis and subcutaneous tissue until contacting host lymphatic channels...Derivative O. volvulus Associated with arachidonic acid pathway and requires iNOS Dermatitis in response to rapid death of MF in the skin M

Immunization with L. sigmodontis Microfilariae Reduces Peripheral Microfilaraemia after Challenge Infection by Inhibition of Filarial Embryogenesis

PubMed Central

Ziewer, Sebastian; Hübner, Marc P.; Dubben, Bettina; Hoffmann, Wolfgang H.; Bain, Odile; Martin, Coralie; Hoerauf, Achim; Specht, Sabine

2012-01-01

Background Lymphatic filariasis and onchocerciasis are two chronic diseases mediated by parasitic filarial worms causing long term disability and massive socioeconomic problems. Filariae are transmitted by blood-feeding mosquitoes that take up the first stage larvae from an infected host and deliver it after maturation into infective stage to a new host. After closure of vector control programs, disease control relies mainly on mass drug administration with drugs that are primarily effective against first stage larvae and require many years of annual/biannual administration. Therefore, there is an urgent need for alternative treatment ways, i.e. other effective drugs or vaccines. Methodology/Principal Findings Using the Litomosoides sigmodontis murine model of filariasis we demonstrate that immunization with microfilariae together with the adjuvant alum prevents mice from developing high microfilaraemia after challenge infection. Immunization achieved 70% to 100% protection in the peripheral blood and in the pleural space and furthermore strongly reduced the microfilarial load in mice that remained microfilaraemic. Protection was associated with the impairment of intrauterine filarial embryogenesis and with local and systemic microfilarial-specific host IgG, as well as IFN-γ secretion by host cells from the site of infection. Furthermore immunization significantly reduced adult worm burden. Conclusions/Significance Our results present a tool to understand the immunological basis of vaccine induced protection in order to develop a microfilariae-based vaccine that reduces adult worm burden and prevents microfilaraemia, a powerful weapon to stop transmission of filariasis. PMID:22413031

Vectorborne diseases in West Africa: geographic distribution and geospatial characteristics.

PubMed

Ratmanov, Pavel; Mediannikov, Oleg; Raoult, Didier

2013-05-01

This paper provides an overview of the methods in which geographic information systems (GIS) and remote sensing (RS) technology have been used to visualise and analyse data related to vectorborne diseases (VBD) in West Africa and to discuss the potential for these approaches to be routinely included in future studies of VBDs. GIS/RS studies of diseases that are associated with a specific geographic landscape were reviewed, including malaria, human African trypanosomiasis, leishmaniasis, lymphatic filariasis, Loa loa filariasis, onchocerciasis, Rift Valley fever, dengue, yellow fever, borreliosis, rickettsioses, Buruli ulcer and Q fever. RS data and powerful spatial modelling methods improve our understanding of how environmental factors affect the vectors and transmission of VBDs. There is great potential for the use of GIS/RS technologies in the surveillance, prevention and control of vectorborne and other infectious diseases in West Africa.

Insights into host-finding by Culex mosquitoes: New tools for surveillance?

USDA-ARS?s Scientific Manuscript database

Culex mosquitoes are important vectors of pathogens and parasites causing diseases such as West Nile virus, St. Louis encephalitis, Japanese encephalitis, Venezuelan equine encephalitis and bancroftian filariasis. Surveillance of these species is based on traps using conventional mosquito attractan...

The Impact of Cultural Behaviours, Local Beliefs, and Practices on Emerging Parasitic Diseases in Tropical Africa

ERIC Educational Resources Information Center

Onwuliri, Celestine O. E.; Anosike, Jude C.; Oguoma, Chibuzor; Onwuliri, Viola A.; Nwoke, Betram E. B.; Dozie, Ikechukwu, N. S.; Iwuala, Moses O. E.

2005-01-01

The scourge of emerging parasitic diseases (e.g., urinary schistosomiasis, ascariasis, malaria, chagas disease, leishmaniasis, trachoma, trichiuriasis, taeniasis, dracunculiasis, sleeping sickness, filariasis) causes tremendous pain, suffering, and eventually death in tropical African communities. Patterns of transmission of these emerging…

Laboratory and field evaluation of medicinal plant extracts against filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae)

USDA-ARS?s Scientific Manuscript database

In this study, chemical extracts of Jatropha curcas, Hyptis suaveolens, Abutilon indicum, and Leucas aspera were tested for toxicity to larvae of the filariasis vector Culex quinquefasciatus. Respective median lethal concentrations (LC50) for hexane, chloroform, ethyl acetate, and methanol extracts...

Larvicidal and adulticidal activity chroman and chromene analogues against susceptible and permethrin-resistant mosquito strains

USDA-ARS?s Scientific Manuscript database

Mosquitoes play a major role as vectors for the transmission of parasitic and viral diseases such as dengue hemorrhagic fever, filariasis, Japanese encephalitis, malaria, schistosomiasis, and yellow fever worldwide. Mosquito borne diseases are presently among the greatest human health problems in th...

Larvicidal activity of few select indigenous plants of North East India against disease vector mosquitoes (Diptera: Culicidae).

PubMed

Dohutia, C; Bhattacharyya, D R; Sharma, S K; Mohapatra, P K; Bhattacharjee, K; Gogoi, K; Gogoi, P; Mahanta, J; Prakash, A

2015-03-01

Mosquitoes are the vectors of several life threatening diseases like dengue, malaria, Japanese encephalitis and lymphatic filariasis, which are widely present in the north-eastern states of India. Investigations on five local plants of north-east India, selected on the basis of their use by indigenous communities as fish poison, were carried out to study their mosquito larvicidal potential against Anopheles stephensi (malaria vector), Stegomyia aegypti (dengue vector) and Culex quinquefasciatus (lymphatic filariasis vector) mosquitoes. Crude Petroleum ether extracts of the roots of three plants viz. Derris elliptica, Linostoma decandrum and Croton tiglium were found to have remarkable larvicidal activity; D. elliptica extract was the most effective and with LC50 value of 0.307 μg/ml its activity was superior to propoxur, the standard synthetic larvicide. Half-life of larvicidal activity of D. elliptica and L. decandrum extracts ranged from 2-4 days.

Ovicidal efficacy of Ageratina adenophora (Family: Asteraceae) against Anopheles stephensi (Diptera: Culicidae)

USDA-ARS?s Scientific Manuscript database

Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the...

Medical Surveillance Monthly Report (MSMR). Volume 6, Number 8, September/October 2000

DTIC Science & Technology

2000-10-01

Rocky mountain spotted fever - - - - Ehrlichiosis - - 2 1 Rubella 1 - - - Encephalitis 1 - 1 - Salmonellosis 38 27 52 76 Filariasis...valley fever - - - - E. coli O157:H7 1 9 9 11 Rocky mountain spotted fever - 3 - - Ehrlichiosis - 1 1 2 Rubella 1 4 - 1 Encephalitis - - 1 1

Medical Surveillance Monthly Report (MSMR). Volume 6, Number 1, January 2000

DTIC Science & Technology

2000-01-01

Rocky mountain spotted fever - 2 2 - Ehrlichiosis - 1 1 - Rubella 3 - - - Encephalitis - - - - Salmonellosis 24 51 63 27 Filariasis - 1...1 1 - - Diphtheria - - - - Rift valley fever - - - - E. Coli 0157:H7 2 1 2 10 Rocky mountain spotted fever - 5 - 4 Ehrlichiosis 2 - 1 1 Rubella - - 1

A Cell-Based Screen Reveals that the Albendazole Metabolite, Albendazole Sulfone, Targets Wolbachia

PubMed Central

Bray, Walter M.; White, Pamela M.; Ruybal, Jordan; Lokey, R. Scott; Debec, Alain; Sullivan, William

2012-01-01

Wolbachia endosymbionts carried by filarial nematodes give rise to the neglected diseases African river blindness and lymphatic filariasis afflicting millions worldwide. Here we identify new Wolbachia-disrupting compounds by conducting high-throughput cell-based chemical screens using a Wolbachia-infected, fluorescently labeled Drosophila cell line. This screen yielded several Wolbachia-disrupting compounds including three that resembled Albendazole, a widely used anthelmintic drug that targets nematode microtubules. Follow-up studies demonstrate that a common Albendazole metabolite, Albendazole sulfone, reduces intracellular Wolbachia titer both in Drosophila melanogaster and Brugia malayi, the nematode responsible for lymphatic filariasis. Significantly, Albendazole sulfone does not disrupt Drosophila microtubule organization, suggesting that this compound reduces titer through direct targeting of Wolbachia. Accordingly, both DNA staining and FtsZ immunofluorescence demonstrates that Albendazole sulfone treatment induces Wolbachia elongation, a phenotype indicative of binary fission defects. This suggests that the efficacy of Albendazole in treating filarial nematode-based diseases is attributable to dual targeting of nematode microtubules and their Wolbachia endosymbionts. PMID:23028321

An Annotated Bibliography of the Mosquitoes and Mosquito-Borne Diseases of Guam (Diptera: Culicidae)

DTIC Science & Technology

1976-01-01

of elephantiasis , with 83 Americans and 28 natives admitted during the year with dengue fever, No cases of malaria were known to have originated on...group, p. 109. Mosquito Systematics Vol. 8(4) 1976 -3e *South Pacific Conmission. 1951. Conference of experts on filariasis and elephantiasis . So

Chapter 3. Integration of botanicals and microbial pesticides for the control of dengue vector, Aedes aegypti (Insecta: Diptera: Culicidae)

USDA-ARS?s Scientific Manuscript database

Mosquitoes are the single most important group of insects in terms of public health significance and causing diseases such as malaria, filariasis, dengue fever, Japanese encephalitis and other fevers. There has been an outbreak of Chikungunya and dengue all over the India from 2006 – 2009. Aedes ae...

[Comparative study of infectious diseases in immigrant children from various countries].

PubMed

Huerga Aramburu, H; López-Vélez, R

2004-01-01

Immigrants have a higher risk of contracting some infectious diseases. The aim of this study was to determine and compare the morbidity profile of immigrant children according to their country of origin. We performed a descriptive study of all immigrants aged less than 14 years old who attended the Tropical Medicine Unit of the Ramon y Cajal Hospital in Madrid between 1989 and 2001. A total of 170 children were included (73 % from Africa, 19 % from Latin America, and 5 % from Asia). Seventy-five percent had at least one infectious disease (78 % of Africans and 62 % of Latin Americans) and 27 % were co-infected (> 2 pathogenic agents). The proportion of healthy children was higher (p < 0.05) among Latin Americans (21 %) than among Africans (9 %). The most frequent infectious diseases were malaria (35 %), intestinal parasites (48 %), filariasis (23 %), and viral hepatitis (19 %). Malaria, filariasis and hepatitis were more frequent in Africans than in Americans (p < 0.05). Other helminthic infections (15 %) were more frequent in Americans. In both groups intestinal parasites and tuberculosis (6 %) were prevalent. Of the 36 (21 %) asymptomatic children, 53 % had at least one infectious disease. The most frequently diagnosed diseases in Africans were intestinal parasitosis (35 %), malaria (7 %), cured hepatitis B (15 %), filariasis (12 %) and superficial mycosis (4 %). The most frequent infectious diseases in Latin Americans were intestinal parasitosis (38 %) and visceral toxocariasis (25 %). Infectious diseases and co-infections are frequent in immigrant children, even in those who are asymptomatic. We propose screening of certain infectious diseases in these children according to their country of origin and their length of residence in Spain.

Impact of vectorborne parasitic neglected tropical diseases on child health.

PubMed

Barry, Meagan A; Murray, Kristy O; Hotez, Peter J; Jones, Kathryn M

2016-07-01

Chagas disease, leishmaniasis, onchocerciasis and lymphatic filariasis are all vectorborne neglected tropical diseases (NTDs) that are responsible for significant disease burden in impoverished children and adults worldwide. As vectorborne parasitic diseases, they can all be targeted for elimination through vector control strategies. Examples of successful vector control programmes for these diseases over the past two decades have included the Southern Cone Initiative against Chagas disease, the Kala-azar Control Scheme against leishmaniasis, the Onchocerciasis Control Programme and the lymphatic filariasis control programme in The Gambia. A common vector control component in all of these programmes is the use of adulticides including dichlorodiphenyltrichloroethane and newer synthetic pyrethroid insecticides against the insect vectors of disease. Household spraying has been used against Chagas disease and leishmaniasis, and insecticide-treated bed nets have helped prevent leishmaniasis and lymphatic filariasis. Recent trends in vector control focus on collaborations between programmes and sectors to achieve integrated vector management that addresses the holistic vector control needs of a community rather than approaching it on a disease-by-disease basis, with the goals of increased efficacy, sustainability and cost-effectiveness. As evidence of vector resistance to currently used insecticide regimens emerges, research to develop new and improved insecticides and novel control strategies will be critical in reducing disease burden. In the quest to eliminate these vectorborne NTDs, efforts need to be made to continue existing control programmes, further implement integrated vector control strategies and stimulate research into new insecticides and control methods. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Copper(II) oxide nanoparticles augment antifilarial activity of Albendazole: In vitro synergistic apoptotic impact against filarial parasite Setaria cervi.

PubMed

Zafar, Atif; Ahmad, Irshad; Ahmad, Ajaz; Ahmad, Masood

2016-03-30

Mass treatment of lymphatic filariasis with Albendazole (ABZ), a therapeutic benzimidazole, is fraught with serious limitations such as possible drug resistance and poor macrofilaricidal activity. Therefore, we need to develop new ABZ-based formulations to improve its antifilarial effectiveness. CuO nanoparticles were used as an adjuvant with ABZ to form ABZ-CuO nanocomposite, which was characterized by UV-vis spectroscopy, FT-IR, AFM and SEM. Antifilarial activity of nanocomposite was evaluated using relative motility assay and dye exclusion test in dark and under UV light. ROS generation, antioxidant levels, lipid peroxidation and DNA fragmentation in nanocomposite treated parasites were estimated. Biophysical techniques were employed to ascertain the mode of binding of nanocomposite to parasitic DNA. Nanocomposite increases parasite mortality as compared to ABZ in dark, and its antifilarial effect was increased further under UV light. Elevated ROS production and decline of parasitic-GST and GSH levels were observed in nanocomposite treated worms in dark, and these effects were pronounced further under UV light. Nanocomposite leads to higher DNA fragmentation as compared to ABZ alone. Further, we found that nanocomposite binds parasitic DNA in an intercalative manner where it generates ROS to induce DNA damage. Thus, oxidative stress production due to ROS generation and consequent DNA fragmentation leads to apoptosis in worms. This is the first report supporting CuO nanoparticles as a potential adjuvant with ABZ against filariasis along with enhanced antifilarial activity of nanocomposite under UV light. These findings, thus, indicate that development of ABZ-loaded nanoparticle compounds may serve as promising leads for filariasis treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of larvicidal activity of Acalypha alnifolia Klein ex Willd. (Euphorbiaceae) leaf extract against the malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus (Diptera: Culicidae).

PubMed

Kovendan, Kalimuthu; Murugan, Kadarkarai; Vincent, Savariar

2012-02-01

The leaf extract of Acalypha alnifolia with different solvents - hexane, chloroform, ethyl acetate, acetone and methanol - were tested for larvicidal activity against three important mosquitoes such as malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus. The medicinal plants were collected from the area around Kallar Hills near the Western Ghats, Coimbatore, India. A. alnifolia plant was washed with tap water and shade dried at room temperature. The dried leaves were powdered mechanically using commercial electrical stainless steel blender. The powder 800 g of the leaf material was extract with 2.5 litre of various each organic solvents such as hexane, chloroform, ethyl acetate, acetone, methanol for 8 h using Soxhlet apparatus, and filtered. The crude plant extracts were evaporated to dryness in a rotary vacuum evaporator. The yield of extracts was hexane (8.64 g), chloroform (10.74 g), ethyl acetate (9.14 g), acetone (10.02 g), and methanol (11.43 g). One gram of the each plant residue was dissolved separately in 100 ml of acetone (stock solution) from which different concentrations, i.e., 50, 150, 250, 350 and 450 ppm, was prepared. The hexane, chloroform, ethyl acetate, acetone was moderate considerable mortality; however, the highest larval mortality was methanolic extract observed in three mosquito vectors. The larval mortality was observed after 24 h exposure. No mortality was observed in the control. The early fourth-instar larvae of A. stephensi had values of LC(50) = 197.37, 178.75, 164.34, 149.90 and 125.73 ppm and LC(90) = 477.60, 459.21, 435.07, 416.20 and 395.50 ppm, respectively. The A. aegypti had values of LC(50) = 202.15, 182.58, 160.35, 146.07 and 128.55 ppm and LC(90) = 476.57, 460.83, 440.78, 415.38 and 381.67 ppm, respectively. The C. quinquefasciatus had values of LC(50) = 198.79, 172.48, 151.06, 140.69 and 127.98 ppm and LC(90) = 458.73, 430

Case Report: Filaria or Megasperm? A Cause of an Ultrasonographic "Filarial Dance Sign".

PubMed

Wiggers, J Brad; Jang, Hyun-Jung; Keystone, Jay S

2018-05-14

Bancroftian filariasis can cause genital abnormalities related to chronic inflammation and obstruction of the afferent lymphatic vessels, and may demonstrate a "filarial dance sign" on scrotal ultrasound with mobile echogenic particles observed. We present a patient with a positive "filarial dance sign," travel within Latin America and negative filarial serology.

Further evidence of the cross-reactivity of the Binax NOW® Filariasis ICT cards to non-Wuchereria bancrofti filariae: experimental studies with Loa loa and Onchocerca ochengi.

PubMed

Wanji, Samuel; Amvongo-Adjia, Nathalie; Njouendou, Abdel Jelil; Kengne-Ouafo, Jonas Arnaud; Ndongmo, Winston Patrick Chounna; Fombad, Fanny Fri; Koudou, Benjamin; Enyong, Peter A; Bockarie, Moses

2016-05-05

The immunochromatographic test (ICT) for lymphatic filariasis is a serological test designed for unequivocal detection of circulating Wuchereria bancrofti antigen. It was validated and promoted by WHO as the primary diagnostic tool for mapping and impact monitoring for disease elimination following interventions. The initial tests for specificity and sensitivity were based on samples collected in areas free of loiasis and the results suggested a near 100% specificity for W. bancrofti. The possibility of cross-reactivity with non-Wuchereria bancrofti antigens was not investigated until recently, when false positive results were observed in three independent studies carried out in Central Africa. Associations were demonstrated between ICT positivity and Loa loa microfilaraemia, but it was not clearly established if these false positive results were due to L. loa or can be extended to other filarial nematodes. This study brought further evidences of the cross-reactivity of ICT card with L. loa and Onchocerca ochengi (related to O. volvulus parasite) using in vivo and in vitro systems. Two filarial/host experimental systems (L. loa-baboon and O. ochengi-cattle) and the in vitro maintenance of different stages (microfilariae, infective larvae and adult worm) of the two filariae were used in three experiments per filarial species. First, whole blood and sera samples were prepared from venous blood of patent baboons and cattle, and applied on ICT cards to detect circulating filarial antigens. Secondly, larval stages of L. loa and O. ochengi as well as O. ochengi adult males were maintained in vitro. Culture supernatants were collected and applied on ICT cards after 6, 12 and 24 h of in vitro maintenance. Finally, total worm extracts (TWE) were prepared using L. loa microfilariae (Mf) and O. ochengi microfilariae, infective larvae and adult male worms. TWE were also tested on ICT cards. For each experiment, control assays (whole blood and sera from uninfected babon

Idiopathic scrotal elephantiasis.

PubMed

Hornberger, Brad J; Elmore, James M; Roehrborn, Claus G

2005-02-01

Scrotal lymphedema (scrotal elephantiasis) is a condition that has historically been described in areas endemic to filariasis. We present a unique case of a 22-year-old man with idiopathic lymphedema isolated to the scrotum. After acquired causes of lymphedema were ruled out, the patient was treated with scrotectomy and scrotal reconstruction.

Immunodiagnostic Properties of Wucheraria bancrofti SXP-1, a Potential Filarial Diagnostic Candidate Expressed in Tobacco Plant, Nicotiana tabacum.

PubMed

Ganapathy, Mathangi; Chakravarthi, M; Charles, S Jason; Harunipriya, P; Jaiganesh, S; Subramonian, N; Kaliraj, P

2015-08-01

Transgenic tobacco plants were developed expressing WbSXP-1, a diagnostic antigen isolated from the cDNA library of L3 stage larvae of Wucheraria bancrofti. This antigen produced by recombinant Escherichia coli has been demonstrated by to be successful as potential diagnostic candidate against lymphatic filariasis. A rapid format simple and qualitative flow through immune-filtration diagnostic kit has been developed for the identification of IgG antibodies to the recombinant WbSXP-1 and is being marketed by M/S Span Diagnostics Ltd in India and Africa. Here, we present the results of experiments on the transformation and expression of the same filarial antigen, WbSXP-1, in tobacco plant, Nicotiana tabacum, to produce plant-based diagnostic antigen. It was possible to successfully transform the tobacco plant with WbSXP-1, the integration of the parasite-specific gene in plants was confirmed by PCR amplification and the expression of the filarial protein by Western blotting. The immunoreactivity of the plant-produced WbSXP-1 was assessed based on its reaction with the monoclonal antibodies developed against the E. coli-produced protein. Immunological screening using clinical sera from patients indicates that the plant-produced protein is comparable to E. coli-produced diagnostic antigen. The result demonstrated that plants can be used as suitable expression systems for the production of diagnostic proteins against lymphatic filariasis, a neglected tropical infectious disease which has a negative impact on socioeconomic development. This is the first report of the integration, expression and efficacy of a diagnostic candidate of lymphatic filariasis in plants.Key MessageTransgenic tobacco plants with WbSXP-1, a filarial diagnostic candidate, were developed. The plant-produced protein showed immunoreactivity on par with the E. coli product.

Epidemiology of elephantiasis with special emphasis on podoconiosis in Ethiopia: A literature review.

PubMed

Yimer, Mulat; Hailu, Tadesse; Mulu, Wondemagegn; Abera, Bayeh

2015-06-01

Elephantiasis is a symptom of a variety of diseases that is characterized by the thickening of the skin and underlying tissues, especially in the legs, male genitals and female breasts. Some conditions having this symptom include: Elephantiasis nostras, due to longstanding chronic lymphangitis; Elephantiasis tropica or lymphatic filariasis, caused by a number of parasitic worms, particularly Wuchereria bancrofti; non-filarial elephantiasis or podoconiosis, an immune disease caused by heavy metals affecting the lymph vessels; proteus syndrome, the genetic disorder of the so-called Elephant Man, etc. Podoconiosis is a type of lower limb tropical elephantiasis distinct from lymphatic filariasis. Lymphatic filariasis affects all population at risk, whereas podoconiosis predominantly affects barefoot subsistence farmers in areas with red volcanic soil. Ethiopia is one of the countries with the highest number of podoconiosis patients since many people are at risk to red-clay soil exposure in many parts of the country. The aim of this review was to know the current status and impact of podoconiosis and its relevance to elephantiasis in Ethiopia. To know the epidemiology and disease burden, the literatures published by different scholars were systematically reviewed. The distribution of the disease and knowledge about filarial elephantiasis and podoconiosis are not well known in Ethiopia. It is relatively well studied in southern Ethiopia but data from other parts of the country are limited. Moreover, programmes that focus on diagnosis, treatment, prevention and control of filarial elephantiasis and podoconiosis are also non-existent even in endemic areas. Furthermore, the disease mapping has not been carried out country-wide. Therefore, in order to address these gaps, Ethiopian Ministry of Health needs to take initiative for undertaking concrete research and mapping of the disease in collaboration with stakeholders.

A multi-center field study of two point-of-care tests for circulating Wuchereria bancrofti antigenemia in Africa

PubMed Central

Chesnais, Cédric B.; Awaca-Uvon, Naomi-Pitchouna; Bolay, Fatoma K.; Boussinesq, Michel; Fischer, Peter U.; Gankpala, Lincoln; Meite, Aboulaye; Missamou, François; Pion, Sébastien D.

2017-01-01

Background The Global Programme to Eliminate Lymphatic Filariasis uses point-of-care tests for circulating filarial antigenemia (CFA) to map endemic areas and for monitoring and evaluating the success of mass drug administration (MDA) programs. We compared the performance of the reference BinaxNOW Filariasis card test (ICT, introduced in 1997) with the Alere Filariasis Test Strip (FTS, introduced in 2013) in 5 endemic study sites in Africa. Methodology The tests were compared prior to MDA in two study sites (Congo and Côte d'Ivoire) and in three sites that had received MDA (DRC and 2 sites in Liberia). Data were analyzed with regard to % positivity, % agreement, and heterogeneity. Models evaluated potential effects of age, gender, and blood microfilaria (Mf) counts in individuals and effects of endemicity and history of MDA at the village level as potential factors linked to higher sensitivity of the FTS. Lastly, we assessed relationships between CFA scores and Mf in pre- and post-MDA settings. Principal findings Paired test results were available for 3,682 individuals. Antigenemia rates were 8% and 22% higher by FTS than by ICT in pre-MDA and in post-MDA sites, respectively. FTS/ICT ratios were higher in areas with low infection rates. The probability of having microfilaremia was much higher in persons with CFA scores >1 in untreated areas. However, this was not true in post-MDA settings. Conclusions/Significance This study has provided extensive new information on the performance of the FTS compared to ICT in Africa and it has confirmed the increased sensitivity of FTS reported in prior studies. Variability in FTS/ICT was related in part to endemicity level, history of MDA, and perhaps to the medications used for MDA. These results suggest that FTS should be superior to ICT for mapping, for transmission assessment surveys, and for post-MDA surveillance. PMID:28892473

A multi-center field study of two point-of-care tests for circulating Wuchereria bancrofti antigenemia in Africa.

PubMed

Chesnais, Cédric B; Awaca-Uvon, Naomi-Pitchouna; Bolay, Fatoma K; Boussinesq, Michel; Fischer, Peter U; Gankpala, Lincoln; Meite, Aboulaye; Missamou, François; Pion, Sébastien D; Weil, Gary J

2017-09-01

The Global Programme to Eliminate Lymphatic Filariasis uses point-of-care tests for circulating filarial antigenemia (CFA) to map endemic areas and for monitoring and evaluating the success of mass drug administration (MDA) programs. We compared the performance of the reference BinaxNOW Filariasis card test (ICT, introduced in 1997) with the Alere Filariasis Test Strip (FTS, introduced in 2013) in 5 endemic study sites in Africa. The tests were compared prior to MDA in two study sites (Congo and Côte d'Ivoire) and in three sites that had received MDA (DRC and 2 sites in Liberia). Data were analyzed with regard to % positivity, % agreement, and heterogeneity. Models evaluated potential effects of age, gender, and blood microfilaria (Mf) counts in individuals and effects of endemicity and history of MDA at the village level as potential factors linked to higher sensitivity of the FTS. Lastly, we assessed relationships between CFA scores and Mf in pre- and post-MDA settings. Paired test results were available for 3,682 individuals. Antigenemia rates were 8% and 22% higher by FTS than by ICT in pre-MDA and in post-MDA sites, respectively. FTS/ICT ratios were higher in areas with low infection rates. The probability of having microfilaremia was much higher in persons with CFA scores >1 in untreated areas. However, this was not true in post-MDA settings. This study has provided extensive new information on the performance of the FTS compared to ICT in Africa and it has confirmed the increased sensitivity of FTS reported in prior studies. Variability in FTS/ICT was related in part to endemicity level, history of MDA, and perhaps to the medications used for MDA. These results suggest that FTS should be superior to ICT for mapping, for transmission assessment surveys, and for post-MDA surveillance.

Evaluation of three traps for sampling Aedes polynesiensis and other mosquito species in American Samoa.

PubMed

Schmaedick, Mark A; Ball, Tamara S; Burkot, Thomas R; Gurr, Neil E

2008-06-01

The efficacy of the recently developed BG-Sentinel mosquito trap baited with BG-Lure (a combination of lactic acid, ammonia, and caproic acid) was evaluated in American Samoa against the omnidirectional Fay-Prince trap and the Centers for Disease Control and Prevention (CDC) light trap, both baited with carbon dioxide. The BG-Sentinel trap captured the greatest number of the important filariasis and dengue vector Aedes (Stegomyia) polynesiensis at all 3 collection locations; however, its catch rate was not significantly different from that of the Fay-Prince trap at 2 of the 3 trapping locations. The CDC light trap caught very few Ae. polynesiensis. The Fay-Prince trap was more efficient than the other 2 traps for collecting Aedes (Aedimorphus) nocturnus, Aedes (Finlaya) spp., Culex quinquefasciatus, and Culex annulirostris. The efficacy and convenience of the BG-Sentinel suggest further research is warranted to evaluate its potential as a possible efficient and safe alternative to landing catches for sampling Ae. polynesiensis in research and control efforts against filariasis and dengue in the South Pacific.

Preventive chemotherapy as a strategy for elimination of neglected tropical parasitic diseases: endgame challenges.

PubMed

Bockarie, Moses J; Kelly-Hope, Louise A; Rebollo, Maria; Molyneux, David H

2013-08-05

Global efforts to address neglected tropical diseases (NTDs) were stimulated in January 2012 by the London declaration at which 22 partners, including the Bill & Melinda Gates Foundation, World Bank, World Health Organization (WHO) and major pharmaceutical companies committed to sustaining and expanding NTD programmes to eliminate or eradicate 11 NTDs by 2020 to achieve the goals outlined in the recently published WHO road map. Here, we present the current context of preventive chemotherapy for some NTDs, and discuss the problems faced by programmes as they consider the 'endgame', such as difficulties of access to populations in post-conflict settings, limited human and financial resources, and the need to expand access to clean water and improved sanitation for schistosomiasis and soil-transmitted helminthiasis. In the case of onchocerciasis and lymphatic filariasis, ivermectin treatment carries a significant risk owing to serious adverse effects in some patients co-infected with the tropical eye worm Loa loa filariasis. We discuss the challenges of managing complex partnerships, and maintain advocacy messages for the continued support for elimination of these preventable diseases.

Preventive chemotherapy as a strategy for elimination of neglected tropical parasitic diseases: endgame challenges

PubMed Central

Bockarie, Moses J.; Kelly-Hope, Louise A.; Rebollo, Maria; Molyneux, David H.

2013-01-01

Global efforts to address neglected tropical diseases (NTDs) were stimulated in January 2012 by the London declaration at which 22 partners, including the Bill & Melinda Gates Foundation, World Bank, World Health Organization (WHO) and major pharmaceutical companies committed to sustaining and expanding NTD programmes to eliminate or eradicate 11 NTDs by 2020 to achieve the goals outlined in the recently published WHO road map. Here, we present the current context of preventive chemotherapy for some NTDs, and discuss the problems faced by programmes as they consider the ‘endgame’, such as difficulties of access to populations in post-conflict settings, limited human and financial resources, and the need to expand access to clean water and improved sanitation for schistosomiasis and soil-transmitted helminthiasis. In the case of onchocerciasis and lymphatic filariasis, ivermectin treatment carries a significant risk owing to serious adverse effects in some patients co-infected with the tropical eye worm Loa loa filariasis. We discuss the challenges of managing complex partnerships, and maintain advocacy messages for the continued support for elimination of these preventable diseases. PMID:23798692

Primary Intestinal Lymphangiectasia (Waldmann's Disease) Presenting with Chylous Effusions in a 15-Year-Old.

PubMed

Surampalli, Vijay; Ramaswamy, Srinath; Surendran, Deepanjali; Bammigatti, Chanaveerappa; Swaminathan, Rathinam Palamalai

2017-08-01

Primary Intestinal Lymphangiectasia (PIL) is a rare disease of unknown aetiology which presents in the paediatric age group with anasarca, diarrhoea, hypoproteinaemia, lymphoedema and chylous effusions. Tuberculosis, filariasis, chest trauma, malignancies and haematological disorders usually contribute to most cases of secondary lymphangiectasia and chylous effusions. We hereby describe a case of PIL presenting with chylous effusions which remained undiagnosed for eight years.

[Clinical microbiology laboratory and imported parasitic diseases].

PubMed

Martín-Rabadán, Pablo; Martínez-Ruiz, Rocío; Cuadros, Juan; Cañavate, Carmen

2010-12-01

Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis. Copyright © 2010 Elsevier España, S.L. All rights reserved.

Flight capacity of adult Culex pipiens pallens (Diptera: Culicidae) in relation to gender and day-age.

PubMed

Cui, Jianxin; Li, Shujuan; Zhao, Ping; Zou, Fumin

2013-09-01

Culex pipiens pallens (L.) is the most common mosquito in houses of central and northern China. It is the primary vector of lymphatic filariasis and Japanese encephalitis. The flight range of mosquitoes is an important factor predicting the risk area of transmission of mosquito-borne pathogens to vertebrate hosts. The flight performance of Cx. pipiens pallens was measured with a 26-channel computer-monitored flight-mill system. We found that females had longer flight capability than males for total flight distance (TFD) and total flight duration (TFDr), and females flew faster than males based on mean flight velocity. No significant difference in flight capability was found between different age-groups in males. However, certain age-groups of females showed significant differences in TFDr and TFD. Specifically, TFD and TFDr tended to be shortest for 5- and 6-d-old females. These significant differences in flight capability between ages and genders provide insights to determine the size of operational area to achieve effective control of Cx. pipiens pallens and minimize the risk of the related mosquito-borne epidemic diseases of lymphatic filariasis and Japanese encephalitis.

The need of adequate information to achieve total compliance of mass drug administration in Pekalongan

NASA Astrophysics Data System (ADS)

Ginandjar, Praba; Saraswati, Lintang Dian; Taufik, Opik; Nurjazuli; Widjanarko, Bagoes

2017-02-01

World Health Organization (WHO) initiated The Global Program to Eliminate Lymphatic Filariasis (LF) through mass drug administration (MDA). Pekalongan started MDA in 2011. Yet the LF prevalence in 2015 remained exceed the threshold (1%). This study aimed to describe the inhibiting factors related to the compliance of MDA in community level. This was a rapid survey with cross sectional approach. A two-stages random sampling was used in this study. In the first stage, 25 clusters were randomly selected from 27 villages with proportionate to population size (PPS) methods (C-Survey). In the second stage, 10 subjects were randomly selected from each cluster. Subject consisted of 250 respondents from 25 selected clusters. Variables consisted of MDA coverage, practice of taking medication during MDA, enabling and inhibiting factors to MDA in community level. The results showed most respondents had poor knowledge on filariasis, which influence awareness of the disease. Health-illness perception, did not receive the drugs, lactation, side effect, and size of the drugs were dominant factors of non-compliance to MDA. MDA information and community empowerment were needed to improve MDA coverage. Further study to explore the appropriate model of socialization will support the success of MDA program

Physicochemical properties of the modeled structure of astacin metalloprotease moulting enzyme NAS-36 and mapping the druggable allosteric space of Heamonchus contortus, Brugia malayi and Ceanorhabditis elegans via molecular dynamics simulation.

PubMed

Sharma, Om Prakash; Agrawal, Sonali; Kumar, M Suresh

2013-12-01

Nematodes represent the second largest phylum in the animal kingdom. It is the most abundant species (500,000) in the planet. It causes chronic, debilitating infections worldwide such as ascariasis, trichuriasis, hookworm, enterobiasis, strongyloidiasis, filariasis and trichinosis, among others. Molecular modeling tools can play an important role in the identification and structural investigation of molecular targets that can act as a vital candidate against filariasis. In this study, sequence analysis of NAS-36 from H. contortus (Heamonchus contortus), B. malayi (Brugia malayi) and C. elegans (Ceanorhabditis elegans) has been performed, in order to identify the conserved residues. Tertiary structure was developed for an insight into the molecular structure of the enzyme. Molecular Dynamics Simulation (MDS) studies have been carried out to analyze the stability and the physical properties of the proposed enzyme models in the H. contortus, B. malayi and C. elegans. Moreover, the drug binding sites have been mapped for inhibiting the function of NAS-36 enzyme. The molecular identity of this protease could eventually demonstrate how ex-sheathment is regulated, as well as provide a potential target of anthelmintics for the prevention of nematode infections.

Biosurveillance Technology: Providing Situational Awareness through Increased Information Sharing

DTIC Science & Technology

2011-09-01

Sri Lanka, there are “separate vertical programmes [sic] to control and monitor malaria , filariasis, leprosy, respiratory diseases, human rabies...Biohazard Detection System CAP Common Alerting Protocol CDC Centers for Disease Control and Prevention CDC HAN Centers for Disease Control and Prevention...LCDHD Preparedness Program running, I always had complete and total faith that you had everything under control and you would excel at every task. To

Serum alpha-1-acid glycoprotein concentration in clinically healthy puppies and adult dogs and in dogs with various diseases.

PubMed

Yuki, Masashi; Itoh, Hiroshi; Takase, Katsuaki

2010-03-01

alpha-1-acid glycoprotein (AGP) is an acute-phase protein and a serum marker of inflammation and neoplasia in humans. AGP concentrations in diseased dogs and the potential effects of age, breed, and sex have not been elucidated. The purpose of this study was to examine differences in AGP concentration based on age, sex, and breed in a large population of clinically healthy dogs and to compare AGP concentrations in dogs with various diseases. Serum was obtained from clinically healthy puppies (n=74) and adults (n=172) of both sexes, and included mongrels (n=205) and Beagles (n=41). Serum also was obtained from 192 dogs with various diseases, including 8 with pyometra that were sampled before, and 1, 2, 3, and 10 days after surgery. AGP concentration was measured by single radial immunodiffusion. Statistical comparisons were made among age, sex, breed, and disease groups. Serum AGP in healthy adult mongrels was 364+/-106 mg/L (reference interval, 152-576 mg/L). AGP was lowest in newborns (n=11, 122+/-54 mg/L) and gradually increased to adult levels by 3 months of age. Median AGP concentration was highest in dogs with parvovirus (n=17, 2100 mg/L), distemper (n=7, 1250 mg/L), and pyometra (n=18, 2480 mg/L) and was also significantly higher in dogs with acute filariasis, renal failure, urolithiasis, pancreatitis, hepatitis, trauma, hyperadrenocorticism, and immune-mediated hemolytic anemia. Dogs with acute filariasis and acute hepatopathy had significantly higher AGP concentrations than dogs with chronic filariasis and chronic hepatopathy. Serum AGP concentration decreased gradually following surgery for pyometra but remained increased after 10 days (896+/-175 mg/L). Because of significantly lower AGP in puppies, the age of dogs should be considered when using AGP as a marker of disease. Serum AGP may be a useful marker of inflammatory disease in dogs and may help differentiate acute and chronic stages of disease.

Toxicity of Thiophenes from Echinops transiliensis (Asteraceae) against Aedes aegypti (Diptera: Culicidae) Larvae

DTIC Science & Technology

2014-01-01

Toxicity of Thiophenes from Echinops transiliensis (Asteraceae) against Aedes aegypti (Diptera: Culicidae) Larvae by Hiroshi Nakano*a)b)c), Abbas...larvicides against Aedes aegypti. Structural differences among compounds 3, 5, and 8 consisted in differing AcO and OH groups attached to C(3’’) and C(4...serious human diseases including malaria, Japanese encephalitis, yellow fever, dengue, and filariasis. The urban-adapted Aedes aegypti mosquito has become

A Brief Survey of the Mosquitoes of South Sulawesi, Indonesia, with Special Reference to the Identity of ’Anopheles barbirostris’ (Diptera: Culicidae) from the Margolembo Area

DTIC Science & Technology

1977-06-20

mosquitoes hitherto recorded from Sulawesi and adjacent islands is presented. The prevalence of malaria and filariasis in transmigration villages of...East Indian mosquitoes. Bull. Ent. Res. 25: 501-19, illus. 1939. Notes on Dutch East- Indian mosquitoes. Tij&hr. Ent. 82: 91-113, illus. Brug, S...Macdonald, W. W. 1957. Malaysian parasites. XVI. An interim review of the non-anopheline mosquitoes of Malaya. Stud. Inst. Med. Res., Malaya 28: l-34

Detection of Wuchereria bancrofti DNA in paired serum and urine samples using polymerase chain reaction-based systems.

PubMed

Ximenes, Camila; Brandão, Eduardo; Oliveira, Paula; Rocha, Abraham; Rego, Tamisa; Medeiros, Rafael; Aguiar-Santos, Ana; Ferraz, João; Reis, Christian; Araujo, Paulo; Carvalho, Luiz; Melo, Fabio L

2014-12-01

The Global Program for the Elimination of Lymphatic Filariasis (GPELF) aims to eliminate this disease by the year 2020. However, the development of more specific and sensitive tests is important for the success of the GPELF. The present study aimed to standardise polymerase chain reaction (PCR)-based systems for the diagnosis of filariasis in serum and urine. Twenty paired biological urine and serum samples from individuals already known to be positive for Wuchereria bancrofti were collected during the day. Conventional PCR and semi-nested PCR assays were optimised. The detection limit of the technique for purified W. bancrofti DNA extracted from adult worms was 10 fg for the internal systems (WbF/Wb2) and 0.1 fg by using semi-nested PCR. The specificity of the primers was confirmed experimentally by amplification of 1 ng of purified genomic DNA from other species of parasites. Evaluation of the paired urine and serum samples by the semi-nested PCR technique indicated only two of the 20 tested individuals were positive, whereas the simple internal PCR system (WbF/Wb2), which has highly promising performance, revealed that all the patients were positive using both samples. This study successfully demonstrated the possibility of using the PCR technique on urine for the diagnosis of W. bancrofti infection.

Molecular Phylogenetics of Aedes japonicus, a Disease Vector That Recently Invaded Western Europe, North America, and the Hawaiian Islands

DTIC Science & Technology

2010-07-01

the scourge of dengue fever in Central and South America , if not in North America (Gratz 2004, Paupy et al. 2009) , and has become the primary...North America , and the Hawaiian Islands EMILIE C. CAMERON,1 RICHARD C. WILKERSON,2 MOTOYOSHI MOGI,3 ICHIRO MIYAGI,4 TAKAKO TOMA,4 HEUNG-CHUL KIM,5 AND...japonicus The genus Aedes (Diptera: Culicidae) includes the principal vectors of yellow fever, dengue , and aperi- odic lymphatic filariasis (Foster

Microsatellite primers for Culex pipiens quinquefasciatus, the vector of avian malaria in Hawaii

USGS Publications Warehouse

Fonseca, Dina M.; Atkinson, Carter T.; Fleischer, Robert C.

1998-01-01

The southern house mosquito, Culex pipiens quinquefasciatus (Diptera: Culicidae), was introduced accidentally to Hawaii in 1826 (van Riper et al. 1986). There it eventually became the vector of avian malaria, Plasmodium relictum, a disease that severely limits the size and distribution of endemic forest bird populations in Hawaii (Atkinson et al. 1995). Cx.p. quinquefasciatus has a circumtropical distribution and is also the vector for human diseases such as lymphatic filariasis and several encephalitis.

Cross-Reactivity of Filariais ICT Cards in Areas of Contrasting Endemicity of Loa loa and Mansonella perstans in Cameroon: Implications for Shrinking of the Lymphatic Filariasis Map in the Central African Region.

PubMed

Wanji, Samuel; Amvongo-Adjia, Nathalie; Koudou, Benjamin; Njouendou, Abdel Jelil; Chounna Ndongmo, Patrick W; Kengne-Ouafo, Jonas A; Datchoua-Poutcheu, Fabrice R; Fovennso, Bridget Adzemye; Tayong, Dizzle Bita; Fombad, Fanny Fri; Fischer, Peter U; Enyong, Peter I; Bockarie, Moses

2015-11-01

Immunochromatographic card test (ICT) is a tool to map the distribution of Wuchereria bancrofti. In areas highly endemic for loaisis in DRC and Cameroon, a relationship has been envisaged between high L. loa microfilaria (Mf) loads and ICT positivity. However, similar associations have not been demonstrated from other areas with contrasting levels of L. loa endemicity. This study investigated the cross-reactivity of ICT when mapping lymphatic filariasis (LF) in areas with contrasting endemicity levels of loiasis and mansonellosis in Cameroon. A cross-sectional study to assess the prevalence and intensity of W. bancrofti, L. loa and M. perstans was carried out in 42 villages across three regions (East, North-west and South-west) of the Cameroon rainforest domain. Diurnal blood was collected from participants for the detection of circulating filarial antigen (CFA) by ICT and assessment of Mf using a thick blood smear. Clinical manifestations of LF were also assessed. ICT positives and patients clinically diagnosed with lymphoedema were further subjected to night blood collection for the detection of W. bancrofti Mf. Overall, 2190 individuals took part in the study. Overall, 24 individuals residing in 14 communities were tested positive by ICT, with prevalence rates ranging from 0% in the South-west to 2.1% in the North-west. Lymphoedema were diagnosed in 20 individuals with the majority of cases found in the North-west (11/20), and none of them were tested positive by ICT. No Mf of W. bancrofti were found in the night blood of any individual with a positive ICT result or clinical lymphoedema. Positive ICT results were strongly associated with high L. loa Mf intensity with 21 subjects having more than 8,000 L. loa Mf ml/blood (Odds ratio = 15.4; 95%CI: 6.1-39.0; p < 0.001). Similarly, a strong positive association (Spearman's rho = 0.900; p = 0.037) was observed between the prevalence of L. loa and ICT positivity by area: a rate of 1% or more of positive ICT results

Cross-Reactivity of Filariais ICT Cards in Areas of Contrasting Endemicity of Loa loa and Mansonella perstans in Cameroon: Implications for Shrinking of the Lymphatic Filariasis Map in the Central African Region

PubMed Central

Wanji, Samuel; Koudou, Benjamin; Chounna Ndongmo, Patrick W.; Kengne-Ouafo, Jonas A.; Datchoua-Poutcheu, Fabrice R.; Fovennso, Bridget Adzemye; Tayong, Dizzle Bita; Fombad, Fanny Fri; Fischer, Peter U.; Enyong, Peter I.; Bockarie, Moses

2015-01-01

Background Immunochromatographic card test (ICT) is a tool to map the distribution of Wuchereria bancrofti. In areas highly endemic for loaisis in DRC and Cameroon, a relationship has been envisaged between high L. loa microfilaria (Mf) loads and ICT positivity. However, similar associations have not been demonstrated from other areas with contrasting levels of L. loa endemicity. This study investigated the cross-reactivity of ICT when mapping lymphatic filariasis (LF) in areas with contrasting endemicity levels of loiasis and mansonellosis in Cameroon. Methodology/Principal Findings A cross-sectional study to assess the prevalence and intensity of W. bancrofti, L. loa and M. perstans was carried out in 42 villages across three regions (East, North-west and South-west) of the Cameroon rainforest domain. Diurnal blood was collected from participants for the detection of circulating filarial antigen (CFA) by ICT and assessment of Mf using a thick blood smear. Clinical manifestations of LF were also assessed. ICT positives and patients clinically diagnosed with lymphoedema were further subjected to night blood collection for the detection of W. bancrofti Mf. Overall, 2190 individuals took part in the study. Overall, 24 individuals residing in 14 communities were tested positive by ICT, with prevalence rates ranging from 0% in the South-west to 2.1% in the North-west. Lymphoedema were diagnosed in 20 individuals with the majority of cases found in the North-west (11/20), and none of them were tested positive by ICT. No Mf of W. bancrofti were found in the night blood of any individual with a positive ICT result or clinical lymphoedema. Positive ICT results were strongly associated with high L. loa Mf intensity with 21 subjects having more than 8,000 L. loa Mf ml/blood (Odds ratio = 15.4; 95%CI: 6.1–39.0; p < 0.001). Similarly, a strong positive association (Spearman’s rho = 0.900; p = 0.037) was observed between the prevalence of L. loa and ICT positivity by area

The diagnostic challenge of mapping elephantiasis in the Tigray region of northern Ethiopia.

PubMed

Padovese, Valeska; Marrone, Rosalia; Dassoni, Federica; Vignally, Pascal; Barnabas, Gebre A; Morrone, Aldo

2016-05-01

In Ethiopia, lymphatic filariasis and podoconiosis are the two neglected tropical diseases planned to be mapped together within the recently launched Ethiopian neglected tropical diseases master plan (2013-2015). However, other disorders cause tropical lymphedema, and this report aims to identify clinical epidemiological aspects of limb swelling in northern Ethiopia and to provide an algorithm orienting the clinical diagnosis. Medical records of patients with lower limb elephantiasis attending the Italian Dermatological Centre of Mekele, Tigray capital city, over a 4-year period (2005-2009) were retrospectively analyzed. Nine variables were collected from the charts comprising demographic data, job, origin, literacy, clinical, histopathologic, microscopic, and cultural findings. Over a total of 511 patients, lymphedema resulted from trauma (40.7%), chronic venous insufficiency (12.5%), deep mycoses (10.8%), lymphatic filariasis (9.2%), elephantiasis nostras verrucosa (7.0%), tropical ulcer (6.3%), leprosy (4.9%), recurrent infections (3.1%), podoconiosis (1.8%), tuberculosis (1.0%), malignancy (1.3%), Kaposi's sarcoma (1.0%), leishmaniasis (0.2%), and neurofibromatosis (0.2%). Advanced-stage elephantiasis, chronic osteomyelitis, and podoconiosis not previously reported in Tigray were observed. Further epidemiological investigation and training programs addressed to healthcare providers at the peripheral level are needed to detect elephantiasis early, prevent disabilities, and improve patients' quality of life. © 2015 The International Society of Dermatology.

Environmental management: a re-emerging vector control strategy.

PubMed

Ault, S K

1994-01-01

Vector control may be accomplished by environmental management (EM), which consists of permanent or long-term modification of the environment, temporary or seasonal manipulation of the environment, and modifying or changing our life styles and practices to reduce human contact with infective vectors. The primary focus of this paper is EM in the control of human malaria, filariasis, arboviruses, Chagas' disease, and schistosomiasis. Modern EM developed as a discipline based primarily in ecologic principles and lessons learned from the adverse environmental impacts of rural development projects. Strategies such as the suppression of vector populations through the provision of safe water supplies, proper sanitation, solid waste management facilities, sewerage and excreta disposal systems, water manipulation in dams and irrigation systems, vector diversion by zooprophylaxis, and vector exclusion by improved housing, are discussed with appropriate examples. Vectors of malaria, filariasis, Chagas' disease, and schistosomiasis have been controlled by drainage or filling aquatic breeding sites, improved housing and sanitation, the use of expanded polystyrene beads, zooprophylaxis, or the provision of household water supplies. Community participation has been effective in the suppression of dengue vectors in Mexico and the Dominican Republic. Alone or combined with other vector control methods, EM has been proven to be a successful approach to vector control in a number of places. The future of EM in vector control looks promising.

Assessment of family and neighbors of an individual infected with Wuchereria bancrofti from a non-endemic area in the city of Maceió, Brazil.

PubMed

Leite, Anderson B; Lima, Ana R V de; Leite, Renata B; Santos, Rafael V; Gonçalves, Johnathan E L; Rocha, Eliana M M; Fontes, Gilberto

2010-01-01

The family and neighbors of a patient infected with W. bancrofti microfilariae were assessed aiming to evaluate the occurrence of cases of lymphatic filariasis in a non-endemic area in the city of Maceió, in the Brazilian state of Alagoas. The patient had previously lived in an endemic focus; however, he has been living in an area where the parasite has never been detected for the past ten years. Female ingurgitated Culex quinquefasciatus mosquitoes captured in the houses of the microfilaremic individual and of his neighbors in the non-endemic region were also examined by polymerase chain reaction (PCR) technique. The thick blood smear examination, blood membrane filtration, and rapid immunochromatography (antigen search) revealed no infected individuals in the family of the microfilaremic individual. All 334 neighbors undergoing the thick blood smear examination were negative for W. bancrofti microfilariae. In 478 ingurgitated C. quinquefasciatus mosquitoes examined by PCR, no W. bancrofti DNA was detected. The microfilaremic individual had a microfilaremia considered very low according to WHO standards (4 microfilariae/mL of blood). As the vectorial infection depends on microfilaremia, the patient's low parasite load did not determine the contamination of other individuals in the area. Our data have shown that the long-term residence of the microfilaremic individual in the non-endemic region was not sufficient to start a new transmission focus of lymphatic filariasis in Maceió.

A new zoonosis of the cerebrospinal fluid of man probably caused by Meningonema peruzzii, a filaria of the central nervous system of Cercopithecidae.

PubMed

Boussinesq, M; Bain, O; Chabaud, A G; Gardon-Wendel, N; Kamgno, J; Chippaux, J P

1995-06-01

A female fourth stage larva of Meningonema, probably of M. peruzzii Orihel et Esslinger, 1973, was recovered in Cameroon, from the cerebrospinal fluid of a patient harbouring Loa loa, but without any neurological signs. This observation is the first human case of Meningonema (Filarioidea Splendidofilariinae) which usually parasitizes the central nervous system of African Cercopithecinae. However, as indicated by Orihel and Esslinger, it seems probable that the perstans-like microfilariae described in cases of cerebral filariasis in Zimbabwe belonged to the same species.

Aedes aegypti (L.) and Aedes polynesiensis Marks (Diptera: Culicidae) in Moorea, French Polynesia: a study of adult population structures and pathogen (Wuchereria bancrofti and Dirofilaria immitis) infection rates to indicate regional and seasonal epidemiological risk for dengue and filariasis.

PubMed

Russell, Richard C; Webb, Cameron E; Davies, Neil

2005-11-01

Populations of Aedes aegypti (L.) and Aedes polynesiensis (Marks) on Moorea Island, French Polynesia, the local vectors of dengue and filariasis, respectively, were sampled by landing/biting collection at nine localities on the east, north, and west coasts, during the late dry season, early and late wet season (September-May) 2003 and 2004, to investigate epidemiologically important features of the populations and compare them between regions and months. Biting rates of both species tended to increase (but not always significantly) for each species in each region each month from the late dry season to the late wet season, and the north coast region had significantly higher biting rates of Ae. aegypti. Insemination rates of Ae. polynesiensis females (94.5-98.8%) were consistently greater than those of Ae. aegypti (87.5-93.5%) throughout the study, but there was no significant difference in the insemination rates of either species between months and regions. Parity rates were generally highest in north coast samples and lowest in west coast samples for both species and generally increased (albeit not always significantly) by month for each species, with a range of 52.9-88.8% for Ae. polynesiensis and 28.6-53.6% for Ae. aegypti, although the high gravid rate (15.8-45.9%) of Ae. aegypti samples (reflecting its feeding more than once in a gonotrophic cycle) confounded both intraspecific and interspecific comparisons. Filarial infection was rare in Ae. aegypti, although both W. bancrofti and D. immitis were recorded, and infection rates in Ae. polynesiensis increased through the study period in each region for both filarias, with up to 4.6% infected and 1.4% infective for W. bancrofti and up to 6.3% infected and 2.5% infective for D. immitis. For W. bancrofti, infection rates were significantly lower on the west coast and also in the dry season, whereas rates for infective stages were significantly greater in the late wet season. For D. immitis there was no significant

Lymphatic filariasis in Brazilian urban area (Maceió, Alagoas).

PubMed

Fontes, G; Rocha, E M; Brito, A C; Antunes, C M

1998-01-01

A cross-sectional survey conducted among evening students was used to determine the prevalence of Wuchereria bancrofti infection in Maceió, capital of the State of Alagoas, northeast Brazil. A single thick-blood smear was used, being collected between 10 p.m. and 12 a.m. From a total of 29,551 students enrolled at evening elementary schools in the 33 city sectors, 16,569 (56.4%) were random selected for inclusion in the study. From those, 10,857 (65.5%) were interviewed and examined and 73 (0.7%) were found to have microfilaraemia. Autochthonous W. bancrofti carriers live in 10 of the 33 city sectors, suggesting a focal distribution. Moreover, 84% of infections were diagnosed among 29% of all students examined, inhabiting three contiguous sectors at the city central area, presenting infection rates up to 5.3%. Students living in city sectors with prevalence of microfilariae carriers greater than 1% were found to have a higher risk for infection when compared to students from the rest of the town [Relative Odds (RO) 12.8, 95% CI 6.7-25.1]. Eleven positive individuals from non endemic areas were living in Maceió for more than 10 years; time of residence in the area was a major risk factor for infection among students not born in the region (p < 0.01). Regarding sex, male students presented a higher proportion of positive (RO 1.7, 95% CI 1.1-2.9).

Human Intraocular Filariasis Caused by Dirofilaria sp. Nematode, Brazil

PubMed Central

Diniz, Daniel G.; Dantas-Torres, Filipe; Casiraghi, Maurizio; de Almeida, Izabela N.F.; de Almeida, Luciana N.F.; Nascimento dos Santos, Jeannie; Furtado, Adriano Penha; Sobrinho, Edmundo F. de Almeida; Bain, Odile

2011-01-01

A case of human intraocular dirofilariasis is reported from northern Brazil. The nematode was morphologically and phylogenetically related to Dirofilaria immitis but distinct from reference sequences, including those of D. immitis infesting dogs in the same area. A zoonotic Dirofilaria species infesting wild mammals in Brazil and its implications are discussed. PMID:21529396

Human Intraocular Filariasis Caused by Pelecitus sp. Nematode, Brazil

PubMed Central

Bain, Odile; Diniz, Daniel G.; Nascimento dos Santos, Jeannie; Pinto de Oliveira, Norimar; Frota de Almeida, Izabela Negrão; Frota de Almeida, Rafael Negrão; Frota de Almeida, Luciana Negrão; Dantas-Torres, Filipe; Sobrinho, Edmundo Frota de Almeida

2011-01-01

A male nematode was extracted from iris fibers of a man from the Brazilian Amazon region. This nematode belonged to the genus Pelecitus but was distinct from the 16 known species in this genus. Similarities with Pelecitus spp. from neotropical birds suggested an avian origin for this species. PMID:21529397

[Idiopathic scrotal elephantiasis. A case report].

PubMed

López-Caballero, Ignacio; Sánchez-Ruvalcaba, Itzel; Sánchez-Martinez, Luis Carlos; Hernández-Ordoñez, Octavio; Gómez-Lara, Miguel; Flores-Carrillo, Víctor

2014-01-01

Penoscrotal lymphedema (scrotal elephantiasis) is a condition that has been described in areas in which filariasis is endemic. This paper presents a case of a 45-year-old man with idiopathic lymphedema isolated to the scrotum. After acquired causes of lymphedema were ruled out, the patient was treated with scrotectomy and penoscrotal reconstruction. Currently, the patient is receiving follow-up care without evidence of recurrence. Penoscrotal lymphedema may cause symptoms of weakness, immobility and emotional disturbance. Surgery procedure provides a satisfactory cosmetical and functional outcome.

Genital elephantiasis and sexually transmitted infections - revisited.

PubMed

Gupta, Somesh; Ajith, C; Kanwar, Amrinder J; Sehgal, Virendra N; Kumar, Bhushan; Mete, Uttam

2006-03-01

Genital elephantiasis is an important medical problem in the tropics. It usually affects young and productive age group, and is associated with physical disability and extreme mental anguish. The majority of cases are due to filariasis; however, a small but significant proportion of patients develop genital elephantiasis due to bacterial sexually transmitted infections (STIs), mainly lymphogranuloma venereum (LGV) and donovanosis. STI-related genital elephantiasis should be differentiated from elephantiasis due to other causes, including filariasis, tuberculosis, haematological malignancies, iatrogenic, or dermatological diseases. Laboratory investigations like microscopy of tissue smear and nucleic acid amplification test for donovanosis, and serology and polymerase chain reaction for LGV may help in the diagnosis, but in endemic areas, in the absence of laboratory facilities, diagnosis largely depends on clinical characteristics. The causative agent of LGV, Chlamydia trachomatis serovar L1-L3, is a lymphotropic organism which leads to the development of thrombolymphangitis and perilymphangitis, and lymphadenitis. Long-standing oedema, fibrosis and lymphogranulomatous infiltration result in the final picture of elephantiasis. Elephantiasis in donovanosis is mainly due to constriction of the lymphatics which are trapped in the chronic granulomatous inflammatory response generated by the causative agent, Calymmatobacterium (Klebsiella) granulomatis. The LGV-associated genital elephantiasis should be treated with a prolonged course of doxycycline given orally, while donovanosis should be treated with azithromycin or trimethoprim-sulphamethoxazole combination given for a minimum of three weeks. Genital elephantiasis is not completely reversible with medical therapy alone and often needs to be reduced surgically.

Molecular identification and phylogenetic analysis of Wuchereria bancrofti from human blood samples in Egypt.

PubMed

Abdel-Shafi, Iman R; Shoieb, Eman Y; Attia, Samar S; Rubio, José M; Ta-Tang, Thuy-Huong; El-Badry, Ayman A

2017-03-01

Lymphatic filariasis (LF) is a serious vector-borne health problem, and Wuchereria bancrofti (W.b) is the major cause of LF worldwide and is focally endemic in Egypt. Identification of filarial infection using traditional morphologic and immunological criteria can be difficult and lead to misdiagnosis. The aim of the present study was molecular detection of W.b in residents in endemic areas in Egypt, sequence variance analysis, and phylogenetic analysis of W.b DNA. Collected blood samples from residents in filariasis endemic areas in five governorates were subjected to semi-nested PCR targeting repeated DNA sequence, for detection of W.b DNA. PCR products were sequenced; subsequently, a phylogenetic analysis of the obtained sequences was performed. Out of 300 blood samples, W.b DNA was identified in 48 (16%). Sequencing analysis confirmed PCR results identifying only W.b species. Sequence alignment and phylogenetic analysis indicated genetically distinct clusters of W.b among the study population. Study results demonstrated that the semi-nested PCR proved to be an effective diagnostic tool for accurate and rapid detection of W.b infections in nano-epidemics and is applicable for samples collected in the daytime as well as the night time. PCR products sequencing and phylogenitic analysis revealed three different nucleotide sequences variants. Further genetic studies of W.b in Egypt and other endemic areas are needed to distinguish related strains and the various ecological as well as drug effects exerted on them to support W.b elimination.

Relevance of Eosinophilia and Hyper-IgE in Immigrant Children

PubMed Central

Belhassen-García, Moncef; Pardo-Lledías, Javier; Pérez del Villar, Luis; Muro, Antonio; Velasco-Tirado, Virginia; Blázquez de Castro, Ana; Vicente, Belen; García García, Mª Inmaculada; Luis Muñoz Bellido, Juan; Cordero-Sánchez, Miguel

2014-01-01

Abstract Immigrants from undeveloped countries are a growing problem in Europe. Spain has become a frequent destination for immigrants (20% of whom are children) because of its geographic location and its historic and cultural links with Africa and Latin America. Eosinophilia is frequent in adult immigrants, travelers and expatriates coming from tropical areas. However, there are few studies that focus on the incidence and causes of tropical eosinophilia and hyper-IgE in immigrant children. We evaluated, prospectively, the prevalence and causes of eosinophilia and hyper-immunoglobulin E (IgE) in 362 immigrant children coming from Sub-Saharan Africa, Northern Africa and Latin America to Salamanca, Spain, between January 2007 and December 2011. Absolute eosinophilia and hyper-IgE were present in 22.9% and 56.8% of the analyzed children, respectively. The most frequent causes of absolute eosinophilia were filariasis (52.6%), strongyloidiasis (46.8%) and schistosomiasis (28.9%). Filariasis (41.9%), strongyloidiasis (29.6%) and schistosomiasis (22.2%) were the most frequent causes of increased levels of IgE. The area under the ROC curve showed similar values between eosinophil count and IgE levels in the diagnosis of helminthiasis (69% [95% confidence interval (CI) 63%–74%] vs 67% [95% CI 60%–72%], P = 0.24). Eosinophilia and hyper-IgE have a high value as biomarkers of helminthiasis in children coming from tropical and subtropical areas. PMID:25058145

Triple Co-Administration of Ivermectin, Albendazole and Praziquantel in Zanzibar: A Safety Study

PubMed Central

Mohammed, Khalfan A.; Haji, Hamad J.; Gabrielli, Albis-Francesco; Mubila, Likezo; Biswas, Gautam; Chitsulo, Lester; Bradley, Mark H.; Engels, Dirk; Savioli, Lorenzo; Molyneux, David H.

2008-01-01

Background Public health interventions based on distribution of anthelminthic drugs against lymphatic filariasis (LF), onchocerciasis, soil-transmitted helminthiasis (STH) and schistosomiasis have been implemented separately to date. A better use of available resources might be facilitated by a more coordinated approach to control such infections, including the possibility of co-administering the three recommended anthelminthic drugs through a single, large-scale intervention. Methodology/Principal Findings Ivermectin, albendazole and praziquantel were co-administered to 5,055 children and adults living in areas endemic for LF, STH and schistosomiasis in Zanzibar, United Republic of Tanzania, during a pilot intervention aimed at elucidating and quantifying possible side-effects. Subsequently, these drugs were co-administered to about 700,000 individuals during a countrywide intervention targeting a large part of the total population of Zanzibar. Passive and active surveillance measures carried out during both interventions showed that side-effects attributable to the three drugs given at the same time were mild and self-limiting events. Conclusions/Significance Our data suggest that co-administration of ivermectin, albendazole and praziquantel is safe in areas where lymphatic filariasis, soil-transmitted helminthiasis and schistosomiasis are co-endemic and where several rounds of treatment with one or two drugs have been implemented in the past. Passive surveillance measures, however, should be continued and detection, management and reporting of possible side-effects should be considered a key component of any health intervention administering drugs. PMID:18235853

Rapid detection of Wuchereria bancrofti and Brugia malayi in mosquito vectors (Diptera: Culicidae) using a real-time fluorescence resonance energy transfer multiplex PCR and melting curve analysis.

PubMed

Intapan, Pewpan M; Thanchomnang, Tongjit; Lulitanond, Viraphong; Maleewong, Wanchai

2009-01-01

We developed a single-step real-time fluorescence resonance energy transfer (FRET) multiplex polymerase chain reaction (PCR) merged with melting curve analysis for the detection of Wuchereria bancrofti and Brugia malayi DNA in blood-fed mosquitoes. Real-time FRET multiplex PCR is based on fluorescence melting curve analysis of a hybrid of amplicons generated from two families of repeated DNA elements: the 188 bp SspI repeated sequence, specific to W. bancrofti, and the 153-bp HhaI repeated sequence, specific to the genus Brugia and two pairs of specific fluorophore-labeled probes. Both W. bancrofti and B. malayi can be differentially detected in infected vectors by this process through their different fluorescence channel and melting temperatures. The assay could distinguish both human filarial DNAs in infected vectors from the DNAs of Dirofilaria immitis- and Plasmodium falciparum-infected human red blood cells and noninfected mosquitoes and human leukocytes. The technique showed 100% sensitivity and specificity and offers a rapid and reliable procedure for differentially identifying lymphatic filariasis. The introduced real-time FRET multiplex PCR can reduce labor time and reagent costs and is not prone to carry over contamination. The test can be used to screen mosquito vectors in endemic areas and therefore should be a useful diagnostic tool for the evaluation of infection rate of the mosquito populations and for xenomonitoring in the community after eradication programs such as the Global Program to Eliminate Lymphatic Filariasis.

Surgical repair of idiopathic scrotal elephantiasis.

PubMed

Zacharakis, Evangelos; Dudderidge, Tim; Zacharakis, Emmanouil; Ioannidis, Evangelos

2008-02-01

Scrotal lymphedema (scrotal elephantiasis) is uncommon outside of filariasis endemic regions. We present a case of a 65-year-old with idiopathic lymphedema of the scrotum and functional impairment of the penis. The patient underwent surgical excision of the edematous subcutaneous tissues and plastic reconstruction of his penis and scrotum. Three years later, the patient showed no signs of local recurrence, had complete restoration of urinary and sexual function and was extremely satisfied with the result. Surgical management was an effective strategy in the management of scrotal lymphedema in this case.

Filariasis in Travelers Presenting to the GeoSentinel Surveillance Network

PubMed Central

Lipner, Ettie M.; Law, Melissa A.; Barnett, Elizabeth; Keystone, Jay S.; von Sonnenburg, Frank; Loutan, Louis; Prevots, D. Rebecca; Klion, Amy D.; Nutman, Thomas B.

2007-01-01

Background As international travel increases, there is rising exposure to many pathogens not traditionally encountered in the resource-rich countries of the world. Filarial infections, a great problem throughout the tropics and subtropics, are relatively rare among travelers even to filaria-endemic regions of the world. The GeoSentinel Surveillance Network, a global network of medicine/travel clinics, was established in 1995 to detect morbidity trends among travelers. Principal Findings We examined data from the GeoSentinel database to determine demographic and travel characteristics associated with filaria acquisition and to understand the differences in clinical presentation between nonendemic visitors and those born in filaria-endemic regions of the world. Filarial infections comprised 0.62% (n = 271) of all medical conditions reported to the GeoSentinel Network from travelers; 37% of patients were diagnosed with Onchocerca volvulus, 25% were infected with Loa loa, and another 25% were diagnosed with Wuchereria bancrofti. Most infections were reported from immigrants and from those immigrants returning to their county of origin (those visiting friends and relatives); the majority of filarial infections were acquired in sub-Saharan Africa. Among the patients who were natives of filaria-nonendemic regions, 70.6% acquired their filarial infection with exposure greater than 1 month. Moreover, nonendemic visitors to filaria-endemic regions were more likely to present to GeoSentinel sites with clinically symptomatic conditions compared with those who had lifelong exposure. Significance Codifying the filarial infections presenting to the GeoSentinel Surveillance Network has provided insights into the clinical differences seen among filaria-infected expatriates and those from endemic regions and demonstrated that O. volvulus infection can be acquired with short-term travel. PMID:18160987

Studies on the laboratory diagnosis of human filariasis: Preliminary communication

PubMed Central

Goldsmid, J. M.

1970-01-01

Five laboratory methods used for the recovery of microfilariae from the blood were compared for efficiency of recovery and time involved. The methods used were thin blood films, thick blood films, wet preparations, the Polyvidone technique, and the microhaematocrit technique. The last proved superior in both efficiency and saving time. Images PMID:5529998

Prevention and control of neglected tropical diseases: overview of randomized trials, systematic reviews and meta-analyses

PubMed Central

Kappagoda, Shanthi

2014-01-01

Abstract Objective To analyse evidence from randomized controlled trials (RCTs) on the prevention and control of neglected tropical diseases (NTDs) and to identify areas where evidence is lacking. Methods The Cochrane Central Register of Controlled Trials and PubMed were searched for RCTs and the Cochrane Database of Systematic Reviews and PubMed were searched for meta-analyses and systematic reviews, both from inception to 31 December 2012. Findings Overall, 258 RCTs were found on American trypanosomiasis, Buruli ulcer, dengue, geohelminth infection, leishmaniasis, leprosy, lymphatic filariasis, onchocerciasis, rabies, schistosomiasis or trachoma. No RCTs were found on cysticercosis, dracunculiasis, echinococcosis, foodborne trematodes, or human African trypanosomiasis. The most studied diseases were geohelminth infection (51 RCTs) and leishmaniasis (46 RCTs). Vaccines, chemoprophylaxis and interventions targeting insect vectors were evaluated in 113, 99 and 39 RCTs, respectively. Few addressed how best to deliver preventive chemotherapy, such as the choice of dosing interval (10) or target population (4), the population coverage needed to reduce transmission (2) or the method of drug distribution (1). Thirty-one publications containing 32 systematic reviews (16 with and 16 without meta-analyses) were found on American trypanosomiasis, dengue, geohelminths, leishmaniasis, leprosy, lymphatic filariasis, onchocerciasis, schistosomiasis or trachoma. Together, they included only 79 of the 258 published RCTs (30.6%). Of 36 interventions assessed, 8 were judged effective in more than one review. Conclusion Few RCTs on the prevention or control of the principal NTDs were found. Trials on how best to deliver preventive chemotherapy were particularly rare. PMID:24839325

Promoting Evidence to Policy Link on the Control of Infectious Diseases of Poverty in Nigeria: Outcome of A Multi-Stakeholders Policy Dialogue

PubMed Central

Uneke, Chigozie Jesse; Ebeh Ezeoha, Abel; Uro-Chukwu, Henry; Ezeonu, Chinonyelum Thecla; Ogbu, Ogbonnaya; Onwe, Friday; Edoga, Chima

2015-01-01

Background: In Nigeria, malaria, schistosomiasis and lymphatic filariasis are among infectious diseases of poverty (IDP) with severe health burden and require effective policy strategies for their control. In this study, we investigated the value of policy brief and policy dialogue as excellent policymaking mechanisms that enable policymakers to adapt effective evidence informed policy for IDP control. Methods: A policy brief was developed on the control of malaria, schistosomiasis and lymphatic filariasis and subjected to deliberations in a one-day multi-stakeholder policy dialogue held in Ebonyi State Nigeria. A modified cross sectional intervention study design was used in this investigation. Structured pre-tested questionnaires were used to evaluate the policy brief document and policy dialogue process at the end of the policy dialogue. Results: Forty-seven policymakers participated in the dialogue. An analysis of the response on the policy brief regarding context, different features of the problem; policy options and key implementation considerations indicated the mean ratings (MNRs) mostly ranged from 6.40-6.85 on 7 point scale. The over-all assessment of the policy brief had MNR at 6.54. The analysis of the response on the policy dialogue regarding the level of priority of policy issue, opportunity to discuss different features of the problem and options for addressing the problem, and the MNRs mostly ranged from 6.50-6.82. The overall assessment of the policy dialogue had MNR at 6.72. Conclusion: Policy dialogues can allow research evidence to be considered together with views, experiences and tacit knowledge of policymakers and can enhance evidence-to-policy link. PMID:26290826

The application of biomedical engineering techniques to the diagnosis and management of tropical diseases: a review.

PubMed

Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Faisal, Tarig; Neuman, Michael

2015-03-23

This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications.

The fossil tabanids (Diptera Tabanidae): when they began to appreciate warm blood and when they began transmit diseases?

PubMed

Martins-Neto, Rafael Gioia

2003-01-01

A discussion of the known fossil tabanids (Diptera Tabanidae) is presented based on fossil evidence. This includes the origin of the hemathophagy in the Brachycera, more specifically for tabanids. Several tabanid species in the extant fauna are vectors for disease-producing organisms that affect humans and animals. Bacteria, viruses, rickettsiae, protozoa, and filarial worms can be transmitted by them, causing such diseases as anthrax, tularemia, anaplasmosis, various forms of trypanosomiasis, Q fever, and filariasis. However, if tabanids are directly responsible for all of these diseases is not consensual and the known fossil evidence is presented here.

Applications of remote sensing in public health.

NASA Technical Reports Server (NTRS)

Barnes, C. M.; Fuller, C. E.; Schneider, H. J.; Kennedy, E. E.; Jones, H. G.; Morrison, D. R.

1973-01-01

Current research concerning the determination of the habitat of mosquito vectors of disease is discussed. It is shown how advanced interpretative processes have enabled recognition of the breeding areas of salt marsh mosquitoes and the breeding sites of the mosquito responsible for the transmission of St. Louis strain of encephalitis and of human filariasis. In addition, remote sensing data have also been useful in the study of the habitat of endemic strains of Venezuelan encephalitis virus in Florida. The beginning of the application of remote sensing to such public health aspects as air, water, and urban degradation is noted.

Trends in parasitic diseases in the Republic of Korea.

PubMed

Shin, Eun-Hee; Guk, Sang-Mee; Kim, Hyo-Jin; Lee, Soon-Hyung; Chai, Jong-Yil

2008-03-01

In the Republic of Korea, cases of zoonotic, opportunistic and imported parasitoses are being detected increasingly. Vivax malaria disappeared in the late 1970s but re-emerged in 1993 and, currently, 1000-2000 cases occur annually. Brugian filariasis was endemic on offshore islands until 1990 but has now been eradicated. Soil-transmitted helminthiases (ascariasis, trichuriasis and hookworm infections) were highly prevalent until the 1970s but are now well controlled. However, food-borne trematode infections, such as clonorchiasis and intestinal trematodiases (including heterophyidiasis, echinostomiasis and gymnophalloidiasis), each show steady prevalence. This review focuses on trends in parasitic diseases in the Republic of Korea.

Periorbital dirofilariasis—Clinical and imaging findings: Live worm on ultrasound

PubMed Central

Gopinath, Thandre N; Lakshmi, K P; Shaji, P C; Rajalakshmi, P C

2013-01-01

Ocular dirofilariasis is a zoonotic filariasis caused by nematode worm,Dirofilaria. We present a case of dirofilariasis affecting the upper eyelid in a 2-year-old child presenting as an acutely inflammed cyst, from southern Indian state of Kerala. Live adult worm was surgically removed and confirmed to be Dirofilaria repens. Live worm showing continuous movement was seen on the pre-operative high-resolution ultrasound. Ultrasound can be helpful in pre-operative identification of live worm. Imaging findings reported in literature are very few. We describe the clinical, ultrasound, and magnetic resonance imaging (MRI) findings. PMID:23803483

A Storytelling Approach: Insights from the Shambaa.

PubMed

Lamanna, Camillo

2018-03-19

Narrative medicine explores the stories that patients tell; this paper, conversely, looks at some of the stories that patients are told. The paper starts by examining the 'story' told by the Shambaa people of Tanzania to explain the bubonic plague and contrasts this with the stories told by Ghanaian communities to explain lymphatic filariasis. By harnessing insights from memory studies, these stories' memorability is claimed to be due to their use mnemonic devices woven into stories. The paper suggests that stories can be unpatronising, informative, and appropriate vehicles for communicating medical information to all age groups across all cultures.

A novel rapid test for detecting antibody responses to Loa loa infections.

PubMed

Pedram, Bijan; Pasquetto, Valérie; Drame, Papa M; Ji, Yongchang; Gonzalez-Moa, Maria J; Baldwin, Richard K; Nutman, Thomas B; Biamonte, Marco A

2017-07-01

Ivermectin-based mass drug administration (MDA) programs have achieved remarkable success towards the elimination of onchocerciasis and lymphatic filariasis. However, their full implementation has been hindered in Central Africa by the occurrence of ivermectin-related severe adverse events (SAEs) in a subset of individuals with high circulating levels of Loa loa microfilariae. Extending MDA to areas with coincident L. loa infection is problematic, and inexpensive point-of-care tests for L. loa are acutely needed. Herein, we present a lateral flow assay (LFA) to identify subjects with a serological response to Ll-SXP-1, a specific and validated marker of L. loa. The test was evaluated on serum samples from patients infected with L. loa (n = 109) and other helminths (n = 204), as well as on uninfected controls (n = 77). When read with the naked eye, the test was 94% sensitive for L. loa infection and was 100% specific when sera from healthy endemic and non-endemic controls or from those with S. stercoralis infections were used as the comparators. When sera of patients with O. volvulus, W. bancrofti, or M. perstans were used as the comparators, the specificity of the LFA was 82%, 87%, and 88%, respectively. A companion smartphone reader allowed measurement of the test line intensities and establishment of cutoff values. With a cutoff of 600 Units, the assay sensitivity decreased to 71%, but the specificity increased to 96% for O. volvulus, 100% for W. bancrofti, and 100% for M. perstans-infected individuals. The LFA may find applications in refining the current maps of L. loa prevalence, which are needed to eliminate onchocerciasis and lymphatic filariasis from the African continent.

Lymphatic pathology in asymptomatic and symptomatic children with Wuchereria bancrofti infection in children from Odisha, India and its reversal with DEC and albendazole treatment.

PubMed

Kar, Shantanu K; Dwibedi, Bhagirathi; Das, Birendra K; Agrawala, Bikash K; Ramachandran, Cherubala P; Horton, John

2017-10-01

Once interruption of transmission of lymphatic filariasis is achieved, morbidity prevention and management becomes more important. A study in Brugia malayi filariasis from India has shown sub-clinical lymphatic pathology with potential reversibility. We studied a Wuchereria bancrofti infected population, the major contributor to LF globally. Children aged 5-18 years from Odisha, India were screened for W. bancrofti infection and disease. 102 infected children, 50 with filarial disease and 52 without symptoms were investigated by lymphoscintigraphy and then randomized to receive a supervised single oral dose of DEC and albendazole which was repeated either annually or semi-annually. The lymphatic pathology was evaluated six monthly for two years. Baseline lymphoscintigraphy showed abnormality in lower limb lymphatics in 80% of symptomatic (40/50) and 63·5% (33/52) of asymptomatic children. Progressive improvement in baseline pathology was seen in 70·8, 87·3, 98·6, and 98·6% of cases at 6, 12, 18, and 24 months follow up, while in 4·2, 22·5, 47·9 and 64·8%, pathology reverted to normal. This was independent of age (p = 0·27), symptomatic status (p = 0·57) and semi-annual/bi-annual dosing (p = 0·46). Six of eleven cases showed clinical reduction in lymphedema of legs. A significant proportion of a young W. bancrofti infected population exhibited lymphatic pathology which was reversible with annual dosage of DEC and albendazole. This provides evidence for morbidity prevention & treatment of early lymphedema. It can also be used as a tool to improve community compliance during mass drug administration. ClinicalTrials.gov No CTRI/2013/10/004121.

Elimination of neglected tropical diseases in the South-East Asia Region of the World Health Organization.

PubMed

Narain, Jai P; Dash, A P; Parnell, B; Bhattacharya, S K; Barua, S; Bhatia, R; Savioli, L

2010-03-01

The neglected tropical diseases (NTDs), which affect the very poor, pose a major public health problem in the South-East Asia Region of the World Health Organization (WHO). Although more than a dozen NTDs affect the region, over the past five years four of them in particular - leprosy, lymphatic filariasis, visceral leishmaniasis (kala-azar) and yaws - have been targeted for elimination. These four were selected for a number of reasons. First, they affect the WHO South-East Asia Region disproportionately. For example, every year around 67% of all new leprosy cases and 60% of all new cases of visceral leishmaniasis worldwide occur in countries of the region, where as many as 850 million inhabitants are at risk of contracting lymphatic filariasis. In addition, several epidemiological, technological and historical factors that are unique to the region make each of these four diseases amenable to elimination. Safe and effective tools and interventions to achieve these targets are available and concerted efforts to scale them up, singly or in an integrated manner, are likely to lead to success. The World Health Assembly and the WHO Regional Committee, through a series of resolutions, have already expressed regional and global commitments for the elimination of these diseases as public health problems. Such action is expected to have a quick and dramatic impact on poverty reduction and to contribute to the achievement of the Millennium Development Goals. This paper reviews the policy rationale for disease control in the WHO South-East Asia Region, the progress made so far, the lessons learnt along the way, and the remaining challenges and opportunities.

Giant lymphedema of the penis and scrotum: a case report.

PubMed

Vives, Franklin; García-Perdomo, Herney Andrés; Ocampo-Flórez, Ginna Marcela

2016-01-01

Lymphedema of the penis and scrotum is a rare entity characterized by enlargement of the skin and subcutaneous tissue of the genital region due to lymphatic drainage impairment. This clinical condition is more frequent in tropical countries due to a higher incidence of filariasis, which, in turn, is the main etiology. We describe the case of a 33-year-old man with large lymphedema of the scrotum and penis due to an acute and chronic inflammatory process, foreign body granuloma, and marked hyalinization. Four consecutive surgical interventions were necessary to remove the great part of the affected tissue, which enabled satisfactory results and improved the patient's quality of life.

[A case report: elephantiasis].

PubMed

Karagöz, Ergenekon; Karaahmetoğlu, Gökhan; Acar, Ali; Turhan, Vedat; Oncül, Oral; Görenek, Levent

2012-01-01

Klippel-Trenaunay syndrome (KTS) is a rare disease and a syndrome that is characterized by the triad of congenital port wine stains,venous malformations with or without varicose veins, bone or soft tissue hypertrophy. Lymphatic filariasis is a filarial disease which usually occurs with genital anomalies, pathologies associated with lymphedema or elephantiasis caused by a filarial infectious agent. In this case report, a 20-year-old male patient admitted to our clinic for diagnosis and treatment with right leg edema and lesions compatible with dermatological manifestations. In the list of differential diagnosis, filarial elephantiasis was also thought, consequently KTS was diagnosed. (Turkiye Parazitol Derg 2012; 36: 188-90).

[Surgical treatment of penile lymphedema associated with hidradenitis suppurativa].

PubMed

García-Tutor, E; Botellé del Hierro, J; San Martín Maya, A; Castro García, J; España, A; Fernández Montero, J; Robles García, J E

2005-05-01

Penoscrotal lymphedema is a rare disease in the developed countries, although it is relatively frequent in tropical countries. The most common cause is filariasis, although in our practice usually is associate to neoplasic and inflammatory processes, surgery, radiotherapy, hidroelectrolitic disbalances and idiopathic. We present a 22 years old patient with penoscrotal lymphedema due to hidradenitis suppurativa. After unsuccessful medical treatment, was performed a total excision of the penile skin and subcutaneous tissue to Buck's fascia. Split thickness skin grafts were used to cover the defect. Even medical management of penoscrotal lymphedema is not effective for most patients, surgery is a safe and effective procedure that gives excellent functional and cosmetic results.

Controlling and Coordinating Development in Vector-Transmitted Parasites

PubMed Central

Matthews, Keith R.

2013-01-01

Vector-borne parasites cause major human diseases of the developing world, including malaria, human African trypanosomiasis, Chagas disease, leishmaniasis, filariasis, and schistosomiasis. Although the life cycles of these parasites were defined over 100 years ago, the strategies they use to optimize their successful transmission are only now being understood in molecular terms. Parasites are now known to monitor their environment in both their host and vector and in response to other parasites. This allows them to adapt their developmental cycles and to counteract any unfavorable conditions they encounter. Here, I review the interactions that parasites engage in with their hosts and vectors to maximize their survival and spread. PMID:21385707

The Application of Biomedical Engineering Techniques to the Diagnosis and Management of Tropical Diseases: A Review

PubMed Central

Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Faisal, Tarig; Neuman, Michael

2015-01-01

This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications. PMID:25806872

Studies on the diagnosis and treatment of human filariasis in Rhodesia.

PubMed

Goldsmid, J M; Rogers, S

1976-07-10

Experiences in Rhodesia with various recovery techniques available for the laboratory diagnosis of infections with Dipetalonema perstans and Wuchereria bancrofti are discussed. A diagnostic laboratory regimen for routine filarial investigations is suggested. Included are preliminary observations on the use of mebendazole (Vermox) for the treatment of D. perstans infections.

Simulation models examining the effect of Brugian filariasis on dengue epidemics.

PubMed

Vaughan, Jefferson A; Focks, Dana A; Turell, Michael J

2009-01-01

Concurrent ingestion of microfilariae (mf) and arboviruses by mosquitoes can enhance the transmission of virus compared with when virus is ingested alone. We studied the effect of mf enhancement on the extrinsic incubation period (EIP) of dengue 1 virus within Aedes aegypti mosquitoes by feeding mosquitoes on blood that either contained virus plus Brugia malayi mf or virus only. Mosquitoes were sampled over time to determine viral dissemination rates. Co-ingestion of mf and virus reduced viral EIP by over half. We used the computer simulation program, DENSiM, to compare the predicted patterns of dengue incidence that would result from such a shortened EIP versus the EIP derived from the control (i.e., virus only) group of mosquitoes. Results indicated that, over the 14-year simulation period, mf-induced acceleration of the EIP would generate more frequent (but not necessarily more severe) epidemics. Potential interactions between arboviruses and hematozoans deserve closer scrutiny.

Productivity Loss Related to Neglected Tropical Diseases Eligible for Preventive Chemotherapy: A Systematic Literature Review

PubMed Central

Rijnsburger, Adriana J.; Severens, Johan L.

2016-01-01

Background Neglected Tropical Diseases (NTDs) not only cause health and life expectancy loss, but can also lead to economic consequences including reduced ability to work. This article describes a systematic literature review of the effect on the economic productivity of individuals affected by one of the five worldwide most prevalent NTDs: lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths (ascariasis, trichuriasis, and hookworm infection) and trachoma. These diseases are eligible to preventive chemotherapy (PCT). Methodology/Principal Findings Eleven bibliographic databases were searched using different names of all NTDs and various keywords relating to productivity. Additional references were identified through reference lists from relevant papers. Of the 5316 unique publications found in the database searches, thirteen papers were identified for lymphatic filariasis, ten for onchocerciasis, eleven for schistosomiasis, six for soil-transmitted helminths and three for trachoma. Besides the scarcity in publications reporting the degree of productivity loss, this review revealed large variation in the estimated productivity loss related to these NTDs. Conclusions It is clear that productivity is affected by NTDs, although the actual impact depends on the type and severity of the NTD as well as on the context where the disease occurs. The largest impact on productivity loss of individuals affected by one of these diseases seems to be due to blindness from onchocerciasis and severe schistosomiasis manifestations; productivity loss due to trachoma-related blindness has never been studied directly. However, productivity loss at an individual level might differ from productivity loss at a population level because of differences in the prevalence of NTDs. Variation in estimated productivity loss between and within diseases is caused by differences in research methods and setting. Publications should provide enough information to enable

“Test and not treat” for onchocerciasis control in a Loa loa endemic area

PubMed Central

Kamgno, Joseph; Pion, Sébastien D.; Chesnais, Cédric B.; Bakalar, Matthew H.; D'Ambrosio, Michael V.; Mackenzie, Charles D.; Nana-Djeunga, Hugues C.; Gounoue-Kamkumo, Raceline; Njitchouang, Guy-Roger; Nwane, Philippe; Tchatchueng-Mbouga, Jules B.; Wanji, Samuel; Stolk, Wilma A.; Fletcher, Daniel A.; Klion, Amy D.; Nutman, Thomas B.; Boussinesq, Michel

2017-01-01

Background Implementation of ivermectin-based community treatment for onchocerciasis or lymphatic filariasis elimination has been delayed in Central Africa because of severe adverse events (SAEs), including death, in people with high levels of circulating Loa loa microfilariae (mf). LoaScope, a rapid field-friendly diagnostic tool to quantify L. loa mf in peripheral blood, permits point-of-care identification of individuals “at risk” for SAEs. Methods A “Test and not Treat” (TaNT) strategy was used to implement ivermectin treatment in the Okola health district in Cameroon, where ivermectin distribution was halted in 1999 after the occurrence of fatal Loa-related SAEs. The LoaScope was used to identify and exclude individuals with >20,000 mf per milliliter of blood (at-risk for SAEs) from ivermectin treatment. Active surveillance for post-treatment adverse events (AEs) was conducted daily for 7 days. Results Between August and October 2015, 16,259 (71.1%) individuals >=5 years of age were tested out of a target population of ~22,800. Among the ivermectin-eligible population, 15,522 (95.5%) received ivermectin; 340 (2.1%) were excluded from ivermectin treatment because of a L. loa density above the risk-threshold and 397 (2.4%) were excluded for pregnancy or illness. No SAEs were observed. Non-severe AEs were recorded in 934 individuals, most (67%) of whom had no detectable L. loa mf. Conclusions The LoaScope-based TaNT strategy permitted safe re-implementation of community-wide ivermectin distribution in a heretofore ‘off limits’ health district in Cameroon and is an extremely promising and practical approach for large-scale ivermectin treatment for lymphatic filariasis and onchocerciasis elimination in Loa loa-endemic areas. PMID:29116890

Molecular evidence on the occurrence of co-infection with Pichia guilliermondii and Wuchereria bancrofti in two filarial endemic districts of India

PubMed Central

2014-01-01

Background Lymphatic filariasis (LF), a vector-borne parasitic disease, is endemic in several parts of India and mostly affects the poor or those with a low-income. The disease results in huge numbers of morbidities, disabilities, and deaths every year. Association of co-infection with other pathogens makes the condition more severe. Although co-infection is becoming a growing area of research, it is yet to emerge as a frontier research topic in filarial research specifically. This study reports the occurrence of a fungal infection in a large number of patients suffering from bancroftian filariasis in two districts of West Bengal, India. Methods Nocturnal blood samples from filarial patients containing parasites and fungus were initially co-cultured, and further the fungus was isolated and characterized. Molecular identification of the isolate was carried out by PCR-based selective amplification and sequencing of highly-conserved D1/D2 region of 26S rDNA, whereas pathogenicity was determined by amplification of the RPS0 gene. A phylogenetic tree was constructed to study the relationship between the isolate and common pathogenic yeasts. The isolate was studied for antibiotic sensitivity, whereas morphological characterization was performed by microscopic techniques. Results The isolate was identified as Pichia guilliermondii and this fungus was found to exist in co-infection with Wuchereria bancrofti in filarial patients. The fungus showed resistance to azole antifungals, griseofulvin, and, amphotericin B, whereas significant susceptibility was evident in cases of nystatin and cycloheximide. A total of 197 out of 222 patients showed this co-infection. Conclusion This study revealed, for the first time, that P. guilliermondii exists as a co-infection in microfilaraemic individuals living in a filarial endemic zone. The findings are important and have relevance to human health, especially for filarial patients. PMID:24708881

Lymphoedema management: an international intersect between developed and developing countries. Similarities, differences and challenges.

PubMed

Stout, Nicole L; Brantus, Pierre; Moffatt, Christine

2012-01-01

Lymphoedema is a chronic swelling condition that contributes to disability, dysfunction and lost quality of life. Significant disparities exist worldwide regarding the availability of resources necessary to identify, treat and manage lymphoedema. This disparity transcends socio-economic status and is a common problem in both developed and developing countries. The overall impact of lymphoedema as a public health problem, however, is underestimated, principally due to the lack of epidemiologic data. These problems pose barriers to optimal identification and management of this disabling, lifelong condition. In 1997, the World Health Organization (50.29) resolved that lymphatic filariasis should be eliminated as a public health problem. A component of this strategy focuses on disability management for those suffering from lymphatic filariasis-related morbidity. This initiative has enhanced lymphoedema awareness in developing countries. However, significant deficits persist in health care providers' knowledge, educational initiatives and basic disease identification and treatment. In developed countries, lymphoedema continues to be an underrecognised condition and assumed to be only cancer-related. Health care resources allocated to treat and manage the disease are insufficient for basic and ongoing care, resulting in disease progression and disability. The International Lymphoedema Framework project, established in 2002, seeks to establish a consensus for best practices in the management of lymphoedema worldwide to reduce this disability burden. A basic global construct for lymphoedema management is needed to decrease morbidity and promote optimal disease management across all cultural and socio-economic boundaries. Many countries are unaware of the importance of lymphoedema management and have not defined a national strategy with respect to this problem. The objective of this article is to define similarities and differences in strategies for lymphoedema management

Effect of Two or Six Doses 800 mg of Albendazole Every Two Months on Loa loa Microfilaraemia: A Double Blind, Randomized, Placebo-Controlled Trial.

PubMed

Kamgno, Joseph; Nguipdop-Djomo, Patrick; Gounoue, Raceline; Téjiokem, Mathurin; Kuesel, Annette C

2016-03-01

Loiasis is a parasitic infection endemic in the African rain forest caused by the filarial nematode Loa loa. Loiasis can be co-endemic with onchocerciasis and/or lymphatic filariasis. Ivermectin, the drug used in the control of these diseases, can induce serious adverse reactions in patients with high L loa microfilaraemia (LLM). A drug is needed which can lower LLM below the level that represents a risk so that ivermectin mass treatment to support onchocerciasis and lymphatic filariasis elimination can be implemented safely. Sixty men and women from a loiasis endemic area in Cameroon were randomized after stratification by screening LLM (≤ 30000, 30001-50000, >50000) to three treatment arms: two doses albendazole followed by 4 doses matching placebo (n = 20), six doses albendazole (n = 20) albendazole or 6 doses matching placebo (n = 20) administered every two months. LLM was measured before each treatment and 14, 18, 21 and 24 months after the first treatment. Monitoring for adverse events occurred three and seven days as well as 2 months after each treatment. None of the adverse events recorded were considered treatment related. The percentages of participants with ≥ 50% decrease in LLM from pre-treatment for ≥ 4 months were 53%, 17% and 11% in the 6-dose, 2-dose and placebo treatment arms, respectively. The difference between the 6-dose and the placebo arm was significant (p = 0.01). The percentages of participants with LLM < 8100 mf/ml for ≥ 4 months were 21%, 11% and 0% in the 6-dose, 2-dose and placebo treatment arms, respectively. The 6-dose regimen reduced LLM significantly, but the reduction was insufficient to eliminate the risk of severe and/or serious adverse reactions during ivermectin mass drug administration in loiasis co-endemic areas.

Effect of Two or Six Doses 800 mg of Albendazole Every Two Months on Loa loa Microfilaraemia: A Double Blind, Randomized, Placebo-Controlled Trial

PubMed Central

Kamgno, Joseph; Nguipdop-Djomo, Patrick; Gounoue, Raceline; Téjiokem, Mathurin; Kuesel, Annette C.

2016-01-01

Background Loiasis is a parasitic infection endemic in the African rain forest caused by the filarial nematode Loa loa. Loiasis can be co-endemic with onchocerciasis and/or lymphatic filariasis. Ivermectin, the drug used in the control of these diseases, can induce serious adverse reactions in patients with high L loa microfilaraemia (LLM). A drug is needed which can lower LLM below the level that represents a risk so that ivermectin mass treatment to support onchocerciasis and lymphatic filariasis elimination can be implemented safely. Methodology Sixty men and women from a loiasis endemic area in Cameroon were randomized after stratification by screening LLM (≤30000, 30001–50000, >50000) to three treatment arms: two doses albendazole followed by 4 doses matching placebo (n = 20), six doses albendazole (n = 20) albendazole or 6 doses matching placebo (n = 20) administered every two months. LLM was measured before each treatment and 14, 18, 21 and 24 months after the first treatment. Monitoring for adverse events occurred three and seven days as well as 2 months after each treatment. Principal Findings None of the adverse events recorded were considered treatment related. The percentages of participants with ≥ 50% decrease in LLM from pre-treatment for ≥ 4 months were 53%, 17% and 11% in the 6-dose, 2-dose and placebo treatment arms, respectively. The difference between the 6-dose and the placebo arm was significant (p = 0.01). The percentages of participants with LLM < 8100 mf/ml for ≥4 months were 21%, 11% and 0% in the 6-dose, 2-dose and placebo treatment arms, respectively. Conclusions/ Significance The 6-dose regimen reduced LLM significantly, but the reduction was insufficient to eliminate the risk of severe and/or serious adverse reactions during ivermectin mass drug administration in loiasis co-endemic areas. PMID:26967331

Screening for parasite infections in immigrant children from low-income countries.

PubMed

Belhassen-García, Moncef; Pardo-Lledías, Javier; Pérez Del Villar, Luis; Velasco-Tirado, Virginia; Siller Ruiz, María; Cordero-Sánchez, Miguel; Vicente, Belen; Hernández Egido, Sara; Muñoz Bellido, Juan Luis; Muro, Antonio

2017-01-01

In Spain, minors represent approximately 20% of the immigration flow. Many of these immigrants come from countries in the tropics and sub-tropics where intestinal parasitic infections caused by helminths and protozoa are one of the major causes of human disease. The main objective of the present work was to describe parasite infections in a group of immigrant children. A prospective evaluation was performed in 373 minors from Sub-Saharan Africa, North Africa, and Latin America. Details were collected from the medical records and physical examination. Urine, stool and peripheral blood samples were obtained for serological and routine laboratory tests. Direct and indirect parasitological tests were also performed. At least 1 parasitic disease was diagnosed in 176 (47.1%) immigrant children, while 77 (20.6%) minors were infected with two or more parasites. The number of parasites was highest in children from Sub-Saharan Africa compared with the rest of the areas of origin (p<.001), and in children from urban areas compared with those from rural areas (OR 1.27 [1.059-1.552], p=.011). The most frequent causes of multiple parasite infection were filariasis plus strongyloidiasis and filariasis plus schistosomiasis. Intestinal parasite infection was diagnosed in 38 cases (13.8%). Logistic regression analysis revealed that for each month of stay, the probability of a positive finding in the stool sample decreased by 0.02% [β=-0.020, (p=.07)]. The high infection rates of parasite diseases in immigrant children point to the need for screening protocols for certain infectious diseases in these children according to their country of origin and their length of residence in Spain. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Giant scrotal elephantiasis of inflammatory etiology: a case report

PubMed Central

Denzinger, Stefan; Watzlawek, Elke; Burger, Maximilian; Wieland, Wolf F; Otto, Wolfgang

2007-01-01

Background Scrotal lymphedema is rare outside endemic filariasis regions in Africa and Asia. It is of variable origin in the western world. Case presentation We present a case of a 40-year-old European man with massive elephantiasis of the scrotum attributed to chronic inflammation of the lower urinary tract caused by urinary outlet obstruction and diabetes mellitus. The patient underwent subtotal scrotectomy saving penis, testes and spermatic cords and followed by scrotal reconstruction with adequate cosmetic and functional outcome. Conclusion In this report we discuss a rare case of scrotal elephantiasis in an European patient, reflect on the etiology and the diagnostic and therapeutic approaches. Surgery can be successful even in giant scrotal elephantiasis. PMID:17543128

Reception of odors and repellents in mosquitoes

PubMed Central

Ray, Anandasankar

2015-01-01

Mosquitoes use their sense of smell to find hosts, nectar, and oviposition sites, and to avoid repellents. A small number of mosquito species are adapted to feed on humans and have a major impact on public health by transmitting malaria, dengue, filariasis, etc. The application of odorants for behavioral control has not been fully realized yet due to complexity of the mosquito olfactory system. Recent progress in molecular and computational tools has enabled rigorous investigations of the mosquito olfactory system function and has started to reveal how specific receptors contribute to attractive and aversive behaviors. Here we discuss recent advances in linking odors to receptors and in exploiting this knowledge in finding attractants and repellents for mosquitoes. PMID:26202080

Other vector-borne parasitic diseases: animal helminthiases, bovine besnoitiosis and malaria.

PubMed

Duvallet, G; Boireau, P

2015-08-01

The parasitic diseases discussed elsewhere in this issue of the Scientific and Technical Review are not the only ones to make use of biological vectors (such as mosquitoes or ticks) or mechanical vectors (such as horse flies or Stomoxys flies). The authors discuss two major groups of vector-borne parasitic diseases: firstly, helminthiasis, along with animal filariasis and onchocerciasis, which are parasitic diseases that often take a heavytoll on artiodactylsthroughoutthe world; secondly, parasitic diseases caused by vector-borne protists, foremost of which is bovine besnoitiosis (or anasarca of cattle), which has recently spread through Europe by a dual mode of transmission (direct and by vector). Other protists, such as Plasmodium and Hepatozoon, are also described briefly.

Modeling mass drug treatment and resistant filaria disease transmission

NASA Astrophysics Data System (ADS)

Fuady, A. M.; Nuraini, N.; Soewono, E.; Tasman, H.; Supriatna, A. K.

2014-03-01

It has been indicated that a long term application of combined mass drug treatment may contribute to the development of drug resistance in lymphatic filariasis. This phenomenon is not well understood due to the complexity of filaria life cycle. In this paper we formulate a mathematical model for the spread of mass drug resistant in a filaria endemic region. The model is represented in a 13-dimensional Host-Vector system. The basic reproductive ratio of the system which is obtained from the next generation matrix, and analysis of stability of both the disease free equilibrium and the coexistence equilibria are shown. Numerical simulation for long term dynamics for possible field conditions is also shown.

Neglected diseases, civil conflicts, and the right to health.

PubMed

Beyrer, Chris; Villar, Juan Carlos; Suwanvanichkij, Voravit; Singh, Sonal; Baral, Stefan D; Mills, Edward J

2007-08-18

Neglected diseases remain one of the largest causes of disease and mortality. In addition to the difficulties in provision of appropriate drugs for specific diseases, many other factors contribute to the prevalence of such diseases and the difficulties in reducing their burden. We address the role that poor governance and politically motivated oppression have on the epidemiology of neglected diseases. We give case examples including filariasis in eastern Burma and vector-borne diseases (Chagas' disease, leishmaniasis, and yellow fever) in Colombia, we show the links between systematic human rights violations and the effects of infectious disease on health. We also discuss the role of researchers in advocating for and researching within oppressed populations.

RRR for NNN-a rapid research response for the Neglected Tropical Disease NGDO Network: a novel framework to challenges faced by the global programs targeting neglected tropical diseases.

PubMed

Toledo, Chelsea E; Jacobson, Julie; Wainwright, Emily C; Ottesen, Eric A; Lammie, Patrick J

2016-03-01

While global programs targeting the control or elimination of five of the neglected tropical diseases (NTDs)-lymphatic filariasis, onchocerciasis, soil-transmitted helminthiasis, schistosomiasis and trachoma-are well underway, they still face many operational challenges. Because of the urgency of 2020 program targets, the Bill & Melinda Gates Foundation and the U.S. Agency for International Development devised a novel rapid research response (RRR) framework to engage national programs, researchers, implementers and WHO in a Coalition for Operational Research on NTDs. After 2 years, this effort has succeeded as an important basis for the research response to programmatic challenges facing NTD programs. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

How do the macrocyclic lactones kill filarial nematode larvae?

PubMed

Wolstenholme, Adrian J; Maclean, Mary J; Coates, Ruby; McCoy, Ciaran J; Reaves, Barbara J

2016-09-01

The macrocyclic lactones (MLs) are one of the few classes of drug used in the control of the human filarial infections, onchocerciasis and lymphatic filariasis, and the only one used to prevent heartworm disease in dogs and cats. Despite their importance in preventing filarial diseases, the way in which the MLs work against these parasites is unclear. In vitro measurements of nematode motility have revealed a large discrepancy between the maximum plasma concentrations achieved after drug administration and the amounts required to paralyze worms. Recent evidence has shed new light on the likely functions of the ML target, glutamate-gated chloride channels, in filarial nematodes and supports the hypothesis that the rapid clearance of microfilariae that follows treatment involves the host immune system.

Identification of Wolbachia Strains in Mosquito Disease Vectors

PubMed Central

Osei-Poku, Jewelna; Han, Calvin; Mbogo, Charles M.; Jiggins, Francis M.

2012-01-01

Wolbachia bacteria are common endosymbionts of insects, and some strains are known to protect their hosts against RNA viruses and other parasites. This has led to the suggestion that releasing Wolbachia-infected mosquitoes could prevent the transmission of arboviruses and other human parasites. We have identified Wolbachia in Kenyan populations of the yellow fever vector Aedes bromeliae and its relative Aedes metallicus, and in Mansonia uniformis and Mansonia africana, which are vectors of lymphatic filariasis. These Wolbachia strains cluster together on the bacterial phylogeny, and belong to bacterial clades that have recombined with other unrelated strains. These new Wolbachia strains may be affecting disease transmission rates of infected mosquito species, and could be transferred into other mosquito vectors as part of control programs. PMID:23185484

Bioefficacy of Some Egyptian Aromatic Plants on Culex pipiens (Diptera: Culicidae) Adults and Larvae

PubMed Central

El Zayyat, Elham A; Soliman, Mohammed I; Elleboudy, Noha A; Ofaa, Shaimaa E

2017-01-01

Background: Protecting the environment from chemical hazards of synthetic insecticides along with offering of new breeding areas for vectors by urbanization indicate the trial of natural insecticides. Methods: The acetone extracts of Anethum graveolens, Ocimum basilicum and Thymus vulgaris were tested for their insecticidal effect on Culex pipiens adults and larvae in different concentrations depending on the technique used. Results: The extracts were significantly effective in all models used with basil being the best in all tested three techniques (LC50= 0.064) in larval feeding, (LC50= 0.330) in CDC bottle assay and (LC50= 13.148) in adults feeding (P< 0.05). Conclusion: The results recommend the eco-friendly studied extracts as candidates for controlling Cx. pipiens the lymphatic filariasis vector. PMID:29026862

Existence of a True Phosphofructokinase in Bacillus sphaericus: Cloning and Sequencing of the pfk Gene

PubMed Central

Alice, Alejandro F.; Pérez-Martínez, Gaspar; Sánchez-Rivas, Carmen

2002-01-01

Some strains of Bacillus sphaericus are entomopathogenic to mosquito larvae, which transmit diseases, such as filariasis and malaria, affecting millions of people worldwide. This species is unable to use hexoses and pentoses as unique carbon sources, which was proposed to be due to the lack of glycolytic enzymes, such as 6-phosphofructokinase (PFK). In this study, PFK activity was detected and the pfk gene was cloned and sequenced. Furthermore, this gene was shown to be present in strains belonging to all the homology groups of this heterogeneous species, in which PFK activity was also detected. A careful sequence analysis revealed the conservation of different catalytic and regulatory residues, as well as the enzyme's phylogenetic affiliation with the family of allosteric ATP-PFK enzymes. PMID:12450869

Implementing Preventive Chemotherapy through an Integrated National Neglected Tropical Disease Control Program in Mali

PubMed Central

Dembélé, Massitan; Bamani, Sanoussi; Dembélé, Robert; Traoré, Mamadou O.; Goita, Seydou; Traoré, Mamadou Namory; Sidibe, Abdoul Karim; Sam, Letitia; Tuinsma, Marjon; Toubali, Emily; MacArthur, Chad; Baker, Shawn K.; Zhang, Yaobi

2012-01-01

Background Mali is endemic for all five targeted major neglected tropical diseases (NTDs). As one of the five ‘fast-track’ countries supported with the United States Agency for International Development (USAID) funds, Mali started to integrate the activities of existing disease-specific national control programs on these diseases in 2007. The ultimate objectives are to eliminate lymphatic filariasis, onchocerciasis and trachoma as public health problems and to reduce morbidity caused by schistosomiasis and soil-transmitted helminthiasis through regular treatment to eligible populations, and the specific objectives were to achieve 80% program coverage and 100% geographical coverage yearly. The paper reports on the implementation of the integrated mass drug administration and the lessons learned. Methodology/Principal Findings The integrated control program was led by the Ministry of Health and coordinated by the national NTD Control Program. The drug packages were designed according to the disease endemicity in each district and delivered through various platforms to eligible populations involving the primary health care system. Treatment data were recorded and reported by the community drug distributors. After a pilot implementation of integrated drug delivery in three regions in 2007, the treatment for all five targeted NTDs was steadily scaled up to 100% geographical coverage by 2009, and program coverage has since been maintained at a high level: over 85% for lymphatic filariasis, over 90% for onchocerciasis and soil-transmitted helminthiasis, around 90% in school-age children for schistosomiasis, and 76–97% for trachoma. Around 10 million people have received one or more drug packages each year since 2009. No severe cases of adverse effects were reported. Conclusions/Significance Mali has scaled up the drug treatment to national coverage through integrated drug delivery involving the primary health care system. The successes and lessons learned in Mali

Using the AD12-ICT rapid-format test to detect Wuchereria bancrofti circulating antigens in comparison to Og4C3-ELISA and nucleopore membrane filtration and microscopy techniques.

PubMed

El-Moamly, Amal Abdul-Rasheed; El-Sweify, Mohamed Aly; Hafez, Mohamad Abdul

2012-09-01

Lymphatic filariasis (LF) continues to be a major source of permanent disability and an impediment to socio-economic development in 73 countries where more than 1 billion people are at risk and over 120 millions are infected. The global drive to eliminate LF necessitates an increasing demand for valid, reliable and rapid diagnostic tests. This study aimed to assess the performance of the AD12 rapid format immunochromatographic test (ICT) to detect Wuchereria bancrofti circulating antigens, against the combined gold standard: TropBio Og4C3-ELISA (enzyme-linked immunosorbent assay) which detects circulating filarial antigen (CFA) and the nucleopore membrane filtration and microscopic examination. This prospective case-control study involved 647 asymptomatic migrant workers from filariasis-endemic countries. Of these specimens, 32 were positive for microfilaremia using the membrane filtration and microscopy, 142 positive by ELISA (of which 32 had microfilaremia), and 128 positive by the ICT (of which 31 had microfilaremia). The performance of the ICT was calculated against 32 true-positive and 90 true-negative cases. For the detection of CFA, the ICT had a sensitivity of 97% (95% confidence interval [CI] 91-103), specificity 100% (95% CI 100-100), Positive Predictive Value (PPV) 100% (95% CI 100-100), Negative Predictive Value (NPV) 99% (95% CI 97-101); and the total accuracy of the test was 99% (95% CI 98-101). The agreement between ICT and ELISA in detecting W. bancrofti antigens was excellent (kappa = 0.934; p = 0.000). In conclusion, the AD12-ICT test for the detection of W. bancrofti-CFA was sensitive and specific and comparable to the performance of ELISA. The ICT would be a useful additional test to facilitate the proposed strategies for control and elimination of LF. Because it is rapid, simple to perform, and does not require the use of special equipment, the ICT may be most appropriate in screening programs and in monitoring the possible risk of introducing

Assessing the presence of Wuchereria bancrofti in vector and human populations from urban communities in Conakry, Guinea.

PubMed

Kouassi, Bernard L; de Souza, Dziedzom K; Goepogui, Andre; Narh, Charles A; King, Sandra A; Mamadou, Baldé S; Diakité, Lamia; Dadzie, Samuel K; Boakye, Daniel A; Utzinger, Jürg; Bockarie, Moses J; Koudou, Benjamin G

2015-09-26

The Global Programme to Eliminate Lymphatic Filariasis was launched in 2000 with the goal of interrupting transmission of lymphatic filariasis (LF) through multiple rounds of mass drug administration (MDA). In Guinea, there is evidence of ongoing LF transmission, but little is known about the most densely populated parts of the country, including the capital Conakry. In order to guide the LF control and elimination efforts, serological and entomological surveys were carried out to determine whether or not LF transmission occurs in Conakry. The prevalence of circulating filarial antigen (CFA) of Wuchereria bancrofti was assessed by an immuno-chromatography test (ICT) in people recruited from all five districts of Conakry. Mosquitoes were collected over a 1-year period, in 195 households in 15 communities. A proportion of mosquitoes were analysed for W. bancrofti, using dissection, loop-mediated isothermal amplification (LAMP) assay and conventional polymerase chain reaction (PCR). CFA test revealed no infection in the 611 individuals examined. A total of 14,334 mosquitoes were collected; 14,135 Culex (98.6 %), 161 Anopheles (1.1 %) and a few other species. Out of 1,312 Culex spp. (9.3 %) and 51 An. gambiae (31.7 %) dissected, none was infected with any stage of the W. bancrofti parasite. However, the LAMP assay revealed that 1.8 % of An. gambiae and 0.31 % of Culex spp. were positive, while PCR determined respective prevalences of 0 % and 0.19 %. This study revealed the presence of W. bancrofti DNA in mosquitoes, despite the apparent absence of infection in the human population. Although MDA interventions are not recommended where the prevalence of ICT is below 1 %, the entomological results are suggestive of the circulation of the parasite in the population of Conakry. Therefore, rigorous surveillance is still warranted so that LF transmission in Conakry would be identified rapidly and adequate responses being implemented.

The interruption of Onchocerca volvulus and Wuchereria bancrofti transmission by integrated chemotherapy in the Obongi focus, North Western Uganda

PubMed Central

Gabriel, Matwale; Tukahebwa, Edridah; Onapa, Ambrose Winston; Tinkitina, Benjamin; Tukesiga, Ephraim; Nyaraga, Michael; Auma, Anna Mary; Habomugisha, Peace; Byamukama, Edson; Oguttu, David; Katabarwa, Moses; Unnasch, Thomas Raymond

2017-01-01

Intervention Few studies have documented the interruption of onchocerciasis and Lymphatic Filariasis (LF) by integrated chemotherapy in Uganda. The study describes the interruption of transmission of the two diseases co-endemic in Obongi focus, north western Uganda. Base line data for Onchocerciasis and LF were collected in 1994 and 2006, respectively. Annual mass drug administration for onchocerciasis (Ivermectin) and Lymphatic Filariasis (Ivermectin + albendazole) was conducted for 20 and 6 years, respectively. Thereafter, assessments by skin snip, larval searches in rivers and human landing catches were performed. Children <10 years were screened for IgG4 antibodies using Ov16 ELISA technique in 2013. LF Pre-TAS and TAS1 were conducted in sentinel sites. ITN coverage and utilization for the implementation unit was also reported. Intervention coverage Onchocerciasis treatment coverage was <80% but improved with the introduction of CDTI in 1999. While for LF, effective coverage of >65% was achieved in the six treatment rounds. Household ownership of ITN’s and utilization was 96% and 72.4%., respectively. Impact Parasitological examinations conducted for onchocerciasis among 807 adults and children, revealed a reduction in mf prevalence from 58% in 1994 to 0% in 2012. Entomological monitoring conducted at the two sites had no single Simulium damnosum fly caught. Serological analysis using Ov16 ELISA for onchocerciasis revealed that out of the 3,308 children <10 years old screened in 2013, only 3/3308 (0.091%) positive cases were detected. All Ov16 positive children were negative when tested for patent infection by skin snip PCR. A reduction in LF microfilaria prevalence from 2.5% (n = 13/522) in 2006 to 0.0% (n = 602) in 2014 was observed. LF TAS1 conducted in 2015 among 1,532 children 6–7 years, all were negative for antigens of W. bancrofti. Conclusion The results concluded that interruption of onchocerciasis and LF has been achieved. PMID:29253862

The burden of neglected tropical diseases in Ethiopia, and opportunities for integrated control and elimination

PubMed Central

2012-01-01

Background Neglected tropical diseases (NTDs) are a group of chronic parasitic diseases and related conditions that are the most common diseases among the 2·7 billion people globally living on less than US$2 per day. In response to the growing challenge of NTDs, Ethiopia is preparing to launch a NTD Master Plan. The purpose of this review is to underscore the burden of NTDs in Ethiopia, highlight the state of current interventions, and suggest ways forward. Results This review indicates that NTDs are significant public health problems in Ethiopia. From the analysis reported here, Ethiopia stands out for having the largest number of NTD cases following Nigeria and the Democratic Republic of Congo. Ethiopia is estimated to have the highest burden of trachoma, podoconiosis and cutaneous leishmaniasis in sub-Saharan Africa (SSA), the second highest burden in terms of ascariasis, leprosy and visceral leishmaniasis, and the third highest burden of hookworm. Infections such as schistosomiasis, trichuriasis, lymphatic filariasis and rabies are also common. A third of Ethiopians are infected with ascariasis, one quarter is infected with trichuriasis and one in eight Ethiopians lives with hookworm or is infected with trachoma. However, despite these high burdens of infection, the control of most NTDs in Ethiopia is in its infancy. In terms of NTD control achievements, Ethiopia reached the leprosy elimination target of 1 case/10,000 population in 1999. No cases of human African trypanosomiasis have been reported since 1984. Guinea worm eradication is in its final phase. The Onchocerciasis Control Program has been making steady progress since 2001. A national blindness survey was conducted in 2006 and the trachoma program has kicked off in some regions. Lymphatic Filariasis, podoconiosis and rabies mapping are underway. Conclusion Ethiopia bears a significant burden of NTDs compared to other SSA countries. To achieve success in integrated control of NTDs, integrated mapping

Biological Control of Mosquito Vectors: Past, Present, and Future

PubMed Central

Benelli, Giovanni; Jeffries, Claire L.; Walker, Thomas

2016-01-01

Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs) is available for most of these diseases and vector control is still the main form of prevention. The limitations of traditional insecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In this review, we outline non-insecticide based strategies that have been implemented or are currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies. PMID:27706105

Allergy and parasites: the measurement of total and specific IgE levels in urban and rural communities in Rhodesia.

PubMed

Merrett, T G; Merrett, J; Cookson, J B

1976-03-01

Eighty adult asthmatics living in an African city had a significantly higher serum IgE level (799 u/ml) than the control group (350 u/ml). A high proportion (78.7%) of the asthmatics had demonstrable circulating mite-specific IgE antibodies. The rural population of a filariasis endemic region was investigated and although no allergic subjects were identified, the group had a significantly higher IgE level (1613 u/ml) than the asthmatics and also showed a relatively high incidence of grass pollen-specific IgE antibodies (35%). The discrepancy between clinical history and laboratory results supports the mast cell saturation hypothesis and suggests: (a) an explanation for the susceptibility to allergy of African and Asian immigrants to Great Britain, and (b) a practical approach for preventing allergic reactions in vivo.

Mosquitoes of the genus Culex in the Suez Canal Governorates.

PubMed

Morsy, T A; el Okbi, L M; Kamal, A M; Ahmed, M M; Boshara, E F

1990-06-01

Mosquitoes are among the most annoying and important vectors of human and animal diseases as malaria, filariasis, yellow fever, rift valley fever...etc. In this paper, it was aimed to study the present status of species of genus Culex in the Suez Canal Governorates after the reconstruction and developmental projects. Five species of Culex were identified: C. pipiens, C. univittatus, C. antennatus, C. poicilipes and C. pusillus. The latter species was represented by two specimens. C. pipiens was the commonest species both indoors and outdoors. C. antennatus and C. poicilipes were found only outdoors. C. pipiens was found all the year round particularly in Spring. Other species were found in Spring and Autumn, except C. antennatus which was found in Summer as well. The results were discussed on the light of work done before.

Spatial epidemiology in zoonotic parasitic diseases: insights gained at the 1st International Symposium on Geospatial Health in Lijiang, China, 2007

PubMed Central

Zhou, Xiao-Nong; Lv, Shan; Yang, Guo-Jing; Kristensen, Thomas K; Bergquist, N Robert; Utzinger, Jürg; Malone, John B

2009-01-01

The 1st International Symposium on Geospatial Health was convened in Lijiang, Yunnan province, People's Republic of China from 8 to 9 September, 2007. The objective was to review progress made with the application of spatial techniques on zoonotic parasitic diseases, particularly in Southeast Asia. The symposium featured 71 presentations covering soil-transmitted and water-borne helminth infections, as well as arthropod-borne diseases such as leishmaniasis, malaria and lymphatic filariasis. The work made public at this occasion is briefly summarized here to highlight the advances made and to put forth research priorities in this area. Approaches such as geographical information systems (GIS), global positioning systems (GPS) and remote sensing (RS), including spatial statistics, web-based GIS and map visualization of field investigations, figured prominently in the presentation. PMID:19193214

Mapping, Bayesian Geostatistical Analysis and Spatial Prediction of Lymphatic Filariasis Prevalence in Africa

PubMed Central

Slater, Hannah; Michael, Edwin

2013-01-01

There is increasing interest to control or eradicate the major neglected tropical diseases. Accurate modelling of the geographic distributions of parasitic infections will be crucial to this endeavour. We used 664 community level infection prevalence data collated from the published literature in conjunction with eight environmental variables, altitude and population density, and a multivariate Bayesian generalized linear spatial model that allows explicit accounting for spatial autocorrelation and incorporation of uncertainty in input data and model parameters, to construct the first spatially-explicit map describing LF prevalence distribution in Africa. We also ran the best-fit model against predictions made by the HADCM3 and CCCMA climate models for 2050 to predict the likely distributions of LF under future climate and population changes. We show that LF prevalence is strongly influenced by spatial autocorrelation between locations but is only weakly associated with environmental covariates. Infection prevalence, however, is found to be related to variations in population density. All associations with key environmental/demographic variables appear to be complex and non-linear. LF prevalence is predicted to be highly heterogenous across Africa, with high prevalences (>20%) estimated to occur primarily along coastal West and East Africa, and lowest prevalences predicted for the central part of the continent. Error maps, however, indicate a need for further surveys to overcome problems with data scarcity in the latter and other regions. Analysis of future changes in prevalence indicates that population growth rather than climate change per se will represent the dominant factor in the predicted increase/decrease and spread of LF on the continent. We indicate that these results could play an important role in aiding the development of strategies that are best able to achieve the goals of parasite elimination locally and globally in a manner that may also account for the effects of future climate change on parasitic infection. PMID:23951194

Commentary: restarting NTD programme activities after the Ebola outbreak in Liberia.

PubMed

Thomas, Brent C; Kollie, Karsor; Koudou, Benjamin; Mackenzie, Charles

2017-05-01

It is widely known that the recent Ebola Virus Disease (EVD) in West Africa caused a serious disruption to the national health system, with many of ongoing disease focused programmes, such as mass drug administration (MDA) for onchocerciasis (ONC), lymphatic filariasis (LF) and schistosomiasis (SCH), being suspended or scaled-down. As these MDA programmes attempt to restart post-EVD it is important to understand the challenges that may be encountered. This commentary addresses the opinions of the major health sectors involved, as well as those of community members, regarding logistic needs and challenges faced as these important public health programmes consider restarting. There appears to be a strong desire by the communities to resume NTD programme activities, although it is clear that some important challenges remain, the most prominent being those resulting from the severe loss of trained staff.

Antifilarial and Antibiotic Activities of Methanolic Extracts of Melaleuca cajuputi Flowers

PubMed Central

Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Mansor, Marzida; Hasan, MS; Kassim, Mustafa

2016-01-01

We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis. PMID:27417081

The Population Biology and Transmission Dynamics of Loa loa.

PubMed

Whittaker, Charles; Walker, Martin; Pion, Sébastien D S; Chesnais, Cédric B; Boussinesq, Michel; Basáñez, María-Gloria

2018-04-01

Endemic to Central Africa, loiasis - or African eye worm (caused by the filarial nematode Loa loa) - affects more than 10 million people. Despite causing ocular and systemic symptoms, it has typically been considered a benign condition, only of public health relevance because it impedes mass drug administration-based interventions against onchocerciasis and lymphatic filariasis in co-endemic areas. Recent research has challenged this conception, demonstrating excess mortality associated with high levels of infection, implying that loiasis warrants attention as an intrinsic public health problem. This review summarises available information on the key parasitological, entomological, and epidemiological characteristics of the infection and argues for the mobilisation of resources to control the disease, and the development of a mathematical transmission model to guide deployment of interventions. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

A Study of Bancroftian Filariasis on the Islands of Batan and Rapu Rapu, Philippines

DTIC Science & Technology

1988-06-01

difficult duefrom which cases of elephantiasis were to the mountainous terrain and absence of reported to have originated (pers. comm. Division of Disease...iis in each village exhibited elephantiasis . The local people attributed the cause to walking were infective with third-stage larvae, and in cool

Bancroftian filariasis in coastal North Trinidad, West Indies: intensity of transmission by Culex quinquefasciatus.

PubMed

Nathan, M B

1981-01-01

The intensity of transmission of Wuchereria bancrofti was measured in a coastal community in north Trinidad where 15% of the residents were microfilaraemic. The only significant vector, Culex quinquefasciatus, was studied in detail to determine seasonal abundance, longevity, infection and infectivity rates. Only 2.1% of the indoor biting population and 7.0% of the indoor resting population were infected. The daily mortality rate of the vector increased with age from 27% at four days to 44 to 47% at 12 days and is considered to be an important factor contributing to the low infectivity rate (0.1%). The mean number of C. quinquefasciatus bites received by a resident of the village during the year of observation was estimated to be 17,948 of which 14 were from mosquitoes harbouring infective larvae of W. bancrofti. The results from similar studies elsewhere are outlined, but the need for standardization of procedure is emphasized before more reliable comparisons can be made.

The domestic cat as a host for Brugian filariasis in South Kalimantan (Borneo), Indonesia.

PubMed

Palmieri, J R; Masbar, S; Purnomo; Marwoto, H A; Tirtokusumo, S; Darwis, F

1985-09-01

Three hundred and twenty-five domestic cats (Felis catus) from six villages of the Hulu Sungai Tengah and Banjar Regency of South Kalimantan (Borneo), Indonesia, were examined for filarial nematodes. Parasites were found in 66 cats, of which 61 (92.4%) had Brugia pahangi, four (6.1%) has B. malayi and one (1.5%) had Dirofilaria repens. Infection rates ranged from 11% to 22% in cats from secondary forest/rice-field habitats, from 15% to 30% in open village/rice-field habitats, to 50% in an open coastal village. In all cases the infection rate of B. malayi in man was greater than in cats from the same collecting area. The number of B. pahangi microfilariae per 20 microliter cat blood ranged from 34 at 1000 hours to 571 at 2200 hours. The results of this study suggest that in this region of Indonesia the domestic cat is not an important host for maintaining B. malayi.

Periodicity of microfilariae of human filariasis analysed by a trigonometric method (Aikat and Das).

PubMed

Tanaka, H

1981-04-01

The microfilarial periodicity of human filariae was characterized statistically by fitting the observed change of microfilaria (mf) counts to the formula of a simple harmonic wave using two parameters, the peak hour (K) and periodicity index (D) (Sasa & Tanaka, 1972, 1974). Later Aikat and Das (1976) proposed a simple calculation method using trigonometry (A-D method) to determine the peak hour (K) and periodicity index (P). All data of microfilarial periodicity analysed previously by the method of Sasa and Tanaka (S-T method) were calculated again by the A-D method in the present study to evaluate the latter method. The results of calculations showed that P was not proportional to D and the ratios of P/D were mostly smaller than expected, especially when P or D was small in less periodic forms. The peak hour calculated by the A-D method did not differ much from that calculated by the S-T method. Goodness of fit was improved slightly by the A-K method in two thirds of analysed data. The classification of human filariae in respect of the type of periodicity was, however, changed little by the results calculated by the A-D method.

Efficacy and safety of co-administered ivermectin plus albendazole for treating soil-transmitted helminths: A systematic review, meta-analysis and individual patient data analysis.

PubMed

Palmeirim, Marta S; Hürlimann, Eveline; Knopp, Stefanie; Speich, Benjamin; Belizario, Vicente; Joseph, Serene A; Vaillant, Michel; Olliaro, Piero; Keiser, Jennifer

2018-04-01

The soil-transmitted helminths (STH), Ascaris lumbricoides, Trichuris trichiura and hookworms, infect 1.5 billion people worldwide and cause an estimated burden of 3.3 million disability-adjusted life years (DALYs). Current control strategies focus on morbidity reduction through preventive chemotherapy (PC) but the most commonly used recommended drugs (albendazole and mebendazole) are particularly inefficacious against T. trichiura. This, together with the threat of emerging drug resistance, calls for new control strategies, including co-administration with other anthelminthics. Ivermectin plus albendazole is widely used against lymphatic filariasis, but its efficacy and safety against STH infections has not yet been fully understood. We conducted a systematic literature review and meta-analysis on the efficacy and safety of ivermectin-albendazole co-administration in five different databases (i.e. PubMed, ISI Web of Science, ScienceDirect, CENTRAL and clinicaltrials.gov) from 1960 to January 2018. Four studies reporting efficacy of ivermectin-albendazole against STH infections and five studies on its safety met the selection criteria and were included for quantitative analysis. Ivermectin-albendazole was significantly associated with lower risk (risk ratio (RR) = 0.44, 95% confidence interval (CI) = 0.31-0.62) for T. trichiura infection after treatment compared to albendazole alone. The co-administration revealed no or only a marginal benefit on cure and egg reduction rates over albendazole alone for A. lumbricoides and hookworm infections. Adverse events (AEs) occurring after ivermectin-albendazole co-administration were mostly mild and transient. Overall, the number of individuals reporting any AE was not different (RR = 1.09, 95% CI = 0.87-1.36) in co-treated and albendazole-treated patients. However, although not statistically significant, sub-group analysis showed a tendency for slightly more AEs in patients with filariasis treated with ivermectin

Efficacy and safety of co-administered ivermectin plus albendazole for treating soil-transmitted helminths: A systematic review, meta-analysis and individual patient data analysis

PubMed Central

Palmeirim, Marta S.; Hürlimann, Eveline; Knopp, Stefanie; Belizario, Vicente; Joseph, Serene A.; Olliaro, Piero

2018-01-01

Background The soil-transmitted helminths (STH), Ascaris lumbricoides, Trichuris trichiura and hookworms, infect 1.5 billion people worldwide and cause an estimated burden of 3.3 million disability-adjusted life years (DALYs). Current control strategies focus on morbidity reduction through preventive chemotherapy (PC) but the most commonly used recommended drugs (albendazole and mebendazole) are particularly inefficacious against T. trichiura. This, together with the threat of emerging drug resistance, calls for new control strategies, including co-administration with other anthelminthics. Ivermectin plus albendazole is widely used against lymphatic filariasis, but its efficacy and safety against STH infections has not yet been fully understood. Methods and findings We conducted a systematic literature review and meta-analysis on the efficacy and safety of ivermectin-albendazole co-administration in five different databases (i.e. PubMed, ISI Web of Science, ScienceDirect, CENTRAL and clinicaltrials.gov) from 1960 to January 2018. Four studies reporting efficacy of ivermectin-albendazole against STH infections and five studies on its safety met the selection criteria and were included for quantitative analysis. Ivermectin-albendazole was significantly associated with lower risk (risk ratio (RR) = 0.44, 95% confidence interval (CI) = 0.31–0.62) for T. trichiura infection after treatment compared to albendazole alone. The co-administration revealed no or only a marginal benefit on cure and egg reduction rates over albendazole alone for A. lumbricoides and hookworm infections. Adverse events (AEs) occurring after ivermectin-albendazole co-administration were mostly mild and transient. Overall, the number of individuals reporting any AE was not different (RR = 1.09, 95% CI = 0.87–1.36) in co-treated and albendazole-treated patients. However, although not statistically significant, sub-group analysis showed a tendency for slightly more AEs in patients with filariasis

Community-based trial of annual versus biannual single-dose ivermectin plus albendazole against Wuchereria bancrofti infection in human and mosquito populations: study protocol for a cluster randomised controlled trial.

PubMed

de Souza, Dziedzom K; Ahorlu, Collins S; Adu-Amankwah, Susan; Otchere, Joseph; Mensah, Sedzro K; Larbi, Irene A; Mensah, George E; Biritwum, Nana-Kwadwo; Boakye, Daniel A

2017-10-02

The Global Programme for the Elimination of Lymphatic Filariasis (GPELF) has been in operation since the year 2000, with the aim of eliminating the disease by the year 2020, following five to six rounds of effective annual mass drug administration (MDA). The treatment regimen is ivermectin (IVM) in combination with diethylcarbamazine (DEC) or albendazole (ALB). In Ghana, MDA has been undertaken since 2001. While the disease has been eliminated in many areas, transmission has persisted in some implementation units that had experienced 15 or more rounds of MDA. Thus, new intervention strategies could eliminate residual infection in areas of persistent transmission and speed up the lymphatic filariasis (LF)-elimination process. This study, therefore, seeks to test the hypothesis that biannual treatment of LF-endemic communities will accelerate the interruption of LF in areas of persistent transmission. A cluster randomised trial will be implemented in LF-endemic communities in Ghana. The interventions will be yearly or twice-yearly MDA delivered to entire endemic communities. Allocation to study group will be by clusters identified using the prevalence of LF. Clusters will be randomised to one of two groups: receiving either (1) annual treatment with IVM + ALB or (2) annual MDA with IVM + ALB, followed by an additional MDA 6 months later. The primary outcome measure is the prevalence of LF infection, assessed by four cross-sectional surveys. Entomological assessments will also be undertaken to evaluate the transmission intensity of the disease in the study clusters. Costs and cost-effectiveness will be evaluated. Among a random subsample of participants, microfilaria prevalence will be assessed longitudinally. A nested process evaluation, using semi-structured interviews, focus group discussions and a stakeholder analysis, will investigate the community acceptability, feasibility and scale-up of each delivery system. It is expected that this study will add to

Genital elephantiasis due to donovanosis: forgotten but not gone yet ...

PubMed

Narang, T; Kanwar, A J

2012-11-01

Genital elephantiasis is a disease that is characterized by massive enlargement of the genitalia. Early aetiological diagnosis is of paramount importance so that development of genital elephantiasis can be prevented; otherwise it is not completely reversible with medical therapy and often requires surgical intervention. Chronic mental distress and disability can result as it interferes with daily/routine activities of the affected individual. Over time, the infectious causes of genital elephantiasis have evolved, from syphilis in the pre-penicillin era to donovanosis, lymphogranuloma venereum and recently filariasis, tuberculosis, leishmaniasis, HIV and chromoblastomycosis. With a declining prevalence globally, donovanosis is at risk of being forgotten as a cause of genital swelling; however, it is known to persist for years without treatment and can lead to complications such as lymphoedema and genital mutilation. We herein present a case of genital elephantiasis that was eventually diagnosed as being due to donovanosis.

Post-ivermectin encephalopathy in Senegal: a case report.

PubMed

Massi, Daniel Gams; Mansare, Mohamed Lelouma; Traoré, Mariétou; Ndiaye, Moustapha; Diop, Amadou Gallo; Ndiaye, Mouhamadou Mansour

2017-01-01

Ivermectin is an ant parasitic drug used for combating onchocerciasis and lymphatic filariasis. It works by inhibiting the function of neurons and muscles, thus causing paralysis of microfilariae. Side effects of this drug have been reported including post-ivermectin encephalopathy requiring emergency care in hospital. We report the case of a 35 years old patient living in rural areas of Senegal who presented two days after a mistake in administration of a second dose of ivermectin, headaches, altered consciousness and bilateral blindness. The workup revealed brain white matter lesions, abnormal liver function tests and biological inflammation without evidence of Loa loa microfilariae in blood and cerebrospinal fluid. Corticosteroid treatment was administered in emergency and patient recovered despite the persistence of bilateral blindness. Inflammatory process seems to have an important role in the pathophysiology of this encephalopathy. We should therefore carefully control the administration of this drugs.

Communicable diseases in the Eastern Mediterranean Region: prevention and control 2010-2011.

PubMed

Haq, Z; Mahjour, J; Khan, W

2013-10-01

One-third of all morbidities and mortalities in the Eastern Mediterranean Region are attributed to communicable diseases. A continued situation of war and conflict, and growing political unrest in the Region, coupled with factors such as travel and migration, and insufficient infrastructure and inadequate technical and managerial capacity ofthe programmes are the major challenges. Despite these challenges, the Region continued making progress towards the elimination of specific diseases such as lymphatic filariasis, measles, malaria, schistosomiasis and dracunculiasis during 2010-11. Coverage for vaccine-preventable diseases was enhanced. Preparedness and response to emerging (e.g. dengue fever in Pakistan and Yemen) and re-emerging (e.g. cholera in Sudan) infections was improved. The Region has continued its efforts for controlling tuberculosis and curbing HIV/AIDS. Looking ahead, the Region aims to improve surveillance and response capacities, legislation issues, coordination, bio-risk and bio-security and quality management in the coming years.

Natural Products as a Source for Treating Neglected Parasitic Diseases

PubMed Central

Ndjonka, Dieudonné; Rapado, Ludmila Nakamura; Silber, Ariel M.; Liebau, Eva; Wrenger, Carsten

2013-01-01

Infectious diseases caused by parasites are a major threat for the entire mankind, especially in the tropics. More than 1 billion people world-wide are directly exposed to tropical parasites such as the causative agents of trypanosomiasis, leishmaniasis, schistosomiasis, lymphatic filariasis and onchocerciasis, which represent a major health problem, particularly in impecunious areas. Unlike most antibiotics, there is no “general” antiparasitic drug available. Here, the selection of antiparasitic drugs varies between different organisms. Some of the currently available drugs are chemically de novo synthesized, however, the majority of drugs are derived from natural sources such as plants which have subsequently been chemically modified to warrant higher potency against these human pathogens. In this review article we will provide an overview of the current status of plant derived pharmaceuticals and their chemical modifications to target parasite-specific peculiarities in order to interfere with their proliferation in the human host. PMID:23389040

Parasitic diseases and urban development.

PubMed Central

Mott, K. E.; Desjeux, P.; Moncayo, A.; Ranque, P.; de Raadt, P.

1990-01-01

The distribution and epidemiology of parasitic diseases in both urban and periurban areas of endemic countries have been changing as development progresses. The following different scenarios involving Chagas disease, lymphatic filariasis, leishmaniasis and schistosomiasis are discussed: (1) infected persons entering nonendemic urban areas without vectors; (2) infected persons entering nonendemic urban areas with vectors; (3) infected persons entering endemic urban areas; (4) non-infected persons entering endemic urban areas; (5) urbanization or domestication of natural zoonotic foci; and (6) vectors entering nonendemic urban areas. Cultural and social habits from the rural areas, such as type of house construction and domestic water usage, are adopted by migrants to urban areas and increase the risk of disease transmission which adversely affects employment in urban populations. As the urban health services must deal with the rise in parasitic diseases, appropriate control strategies for the urban setting must be developed and implemented. PMID:2127380

Mansonella ozzardi and its vectors in the New World: an update with emphasis on the current situation in Haiti.

PubMed

Raccurt, C P

2017-10-25

Mansonella ozzardi (Nematoda: Onchocercidae) is a little studied filarial nematode. This human parasite, transmitted by two families of dipteran vectors, biting midges (most of them members of the genus Culicoides) and blackflies (genus Simulium), is endemic to the Neotropical regions of the New World. With a patchy geographical distribution from southern Mexico to north-western Argentina, human infection with M. ozzardi is highly prevalent in some of the Caribbean islands, along riverine communities in the Amazon Basin, and on both sides of the border between Bolivia and Argentina. Studies conducted in Haiti between 1974 and 1984 allowed the first complete description of the adult worm and permitted clarification of the taxonomic position of this filarial species. This paper reports the known geographical distribution of M. ozzardi in Neotropical regions of the Americas, and focuses on the current situation in Haiti where this filariasis remains a completely neglected public health problem.

Chemotherapeutic reactions of Chandlerella hawkingi, the filarial parasite of the Indian jungle crow, Corvus macrorhynchos (Wagler)

PubMed Central

Chatterjee, R. K.; Sen, A. B.

1969-01-01

1. A high percentage of Indian jungle crows (Corvus macrorhynchos Wagler), found in and around Lucknow, harbour a natural filarial infection Chandlerella hawkingi. The microfilariae of this species are sheathed and show nocturnal periodicity. 2. Fourteen compounds active against other kinds of filariae, especially against Litomosoides carinii, were tested against Ch. hawkingi in jungle crows to find whether this infection would be suitable for routine filarial chemotherapy. This is apparently the first report of systematic screening of antifilarial compounds against an avian filariasis. 3. Tartar emetic (10 mg/kg intravenously, daily for 6 days) and arsenamide (5 mg/kg intraperitoneally, daily for 6 days) proved to be effective in killing adult worms. Trivalent tryparsamide, though effective, was toxic in the doses tried. Diethylcarbamazine and other compounds tested were ineffective. 4. The chemotherapeutic susceptibilities of Ch. hawkingi differ considerably from those of L. carinii and Wuchereria bancrofti. PMID:5774047

Current status and challenge of Human Parasitology teaching in China

PubMed Central

Peng, Hong-Juan; Zhang, Chao; Wang, Chun-Mei; Chen, Xiao-Guang

2012-01-01

Parasitic infection profile in China has been changed greatly with the rapid economic development in China since the 1980s, such as the tremendous decreased infection rate of the soil-borne helminthiasis, the elimination of filariasis, the control of malaria, and the initiation to eradicate malaria in 2020. Some food-borne parasitic infections have increased such as Clonorchiasis, Cysticercosis, and Echinococcosis, probably because of the increased chances of eating out. This trend directly affected the status of Human Parasitology teaching in medical universities, such as the shorten length of this course, re-adjusted contents structure and teaching manners, even the change of the name of this course. In this paper, we analyzed the current status and challenges of Human Parasitology teaching in medical universities, and discussed the requisite contents and manners in course delivery and measures to improve the quality of Human Parasitology teaching in China. PMID:23265609

Mosquito ovicidal properties of Ageratina adenophora (Family: Asteraceae) against filariasis vector, Culex quinquefasciatus (Diptera: Culicidae)

USDA-ARS?s Scientific Manuscript database

Mosquito-borne diseases with an economic impact create loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates. Mosquito control is facing a threat because of the emergence of resistance to synthetic insecticides. Extracts from plants may be alternativ...

Laboratory evaluation of Indian medicinal plants as repellents against malaria, dengue, and filariasis vector mosquitoes.

PubMed

Govindarajan, Marimuthu; Sivakumar, Rajamohan

2015-02-01

Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticides, in the present study, the repellent activity of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of leaf of Erythrina indica and root of Asparagus racemosus were assayed for their repellency against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The crude extract was applied on a membrane used for membrane feeding of unfed mosquitoes in a 1-ft cage. About 50 unfed 3-4-day-old laboratory-reared pathogen-free strains of A. stephensi, A. aegypti, and C. quinquefasciatus were introduced in a 1-ft cage fitted with a membrane with blood for feeding with temperature maintained at 37 °C through circulating water bath maintained at 40-45 °C. Three concentrations (1.0, 2.0, and 5.0 mg/cm(2)) of the crude extracts were evaluated. Repellents in E. indica afforded longer protection time against A. stephensi, A. aegypti, and C. quinquefasciatus than those in A. racemosus at 5.0 mg/cm(2) concentration, and the mean complete protection time ranged from 120 to 210 min with the different extracts tested. In this observation, these two plant crude extracts gave protection against mosquito bites; also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf extract of E. indica and root extract of A. racemosus have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This is the first report on the mosquito repellent activity of the reported A. racemosus and E. indica plants.

Management of adenolymphangitis and lymphoedema due to lymphatic filariasis in resource-limited North-eastern Nigeria.

PubMed

Akogun, O B; Badaki, J A

2011-09-01

Procedures for health facility-based management of lymphoedema and adenolymphangitis (ADL) have proved very effective in some countries. Unfortunately, in resource-poor communities of Africa where health facilities are few, overburdened and inaccessible, an alternative approach is required. Community-based care (CC), patient care (PC) and health facility care (HC) approaches were compared. In the CC arm, communities were required to select one of their members for care-giving to its affected members, while in the PC, participants were allocated to groups under a leader with responsibility for care giving to group members. In HC, care was given by the nearest health facility. Caregivers from the three arms were trained and supplies were kept at the local government health office. At the sixth month of intervention, 325 lymphoedema and adenolymphangitis patients had been recruited into the study as participants. Within 12 months, compliance with hygiene practices increased from 29.4% to 62.6% and ADL episodes declined from 43.1% to 4.4% in the community designs arm and the cost on the health system was minimal. However, in the patient and health care arms, compliance and accessibility to supplies was severely affected by poor coordination, delay in resource collection leading to very minimal effect on lesions, odour, ADL frequency and duration. Participants abandoned the health facilities after the second visit. Community care approach was more culturally acceptable and effective for the management lymphoedema and ADL than other approaches. Copyright © 2010 Elsevier B.V. All rights reserved.

Birthweight in Offspring of Mothers with High Prevalence of Helminth and Malaria Infection in Coastal Kenya

PubMed Central

Fairley, Jessica K.; Bisanzio, Donal; King, Charles H.; Kitron, Uriel; Mungai, Peter; Muchiri, Eric; King, Christopher L.; Malhotra, Indu

2013-01-01

Results of studies on the associations of maternal helminth infection and malaria-helminth co-infection on birth outcomes have been mixed. A group of 696 pregnant women from the Kwale district in Kenya were recruited and tested for malaria and helminth infection at delivery. Birthweight was documented for 664 infants. A total of 42.7% of the mothers were infected with Plasmodium falciparum, 30.6% with Schistosoma haematobium, 36.2% with filariasis, 31.5% with hookworm, and 5.9% with Trichuris trichiura; co-infection was present in 46.7%. Low birthweight (LBW) (weight < 2,500 grams) was present in 15.4% of the offspring, and 8.3% had a weight z-score ≤ 2 SD below the World Health Organization mean. Only gravida, age, and locale had a significant association with LBW. The high prevalence of maternal infection coupled with a higher than expected percentage of LBW highlight a need for further investigation of the association of maternal co-infection with LBW. PMID:23166193

Elephantiasis nostras verrucosa in a patient with systemic sclerosis.

PubMed

Chatterjee, S; Karai, L J

2009-12-01

Elephantiasis nostras verrucosa (ENV) is an unusual skin condition characterized by dermal fibrosis and hyperkeratotic verrucous lesions resulting from chronic nonfilarial lymphoedema. The condition is similar to 'elephantiasis tropica', in which elephantiasis develops secondary to filariasis. Lymphatic obstruction can be primary or due to various causes such as surgery, tumour, radiation, congestive heart failure or obesity. Recurrent attacks of cellulitis lead to further impairment of lymphatic drainage, causing permanent swelling, dermal fibrosis and epidermal thickening. We report a case of a 56-year-old man with systemic sclerosis (SS), who presented with painful lesions on both legs, consistent with ENV. He developed extensive, fungating, papillomatous lesions on the skin of the legs, toes and dorsa of the feet over a period of 3 years. Histology revealed dense dermal fibrosis, oedema of the papillary dermis and extensive pseudo-epitheliomatous changes. To our knowledge, this is the first report of ENV in which SS was considered to be the primary cause for the impairment of lymphatic flow.

Vector-borne diseases in Haiti: a review.

PubMed

Ben-Chetrit, Eli; Schwartz, Eli

2015-01-01

Haiti lies on the western third of the island of Hispaniola in the Caribbean, and is one of the poorest nations in the Western hemisphere. Haiti attracts a lot of medical attention and support due to severe natural disasters followed by disastrous health consequences. Vector-borne infections are still prevalent there with some unique aspects comparing it to Latin American countries and other Caribbean islands. Although vector-borne viral diseases such as dengue and recently chikungunya can be found in many of the Caribbean islands, including Haiti, there is an apparent distinction of the vector-borne parasitic diseases. Contrary to neighboring Carribbean islands, Haiti is highly endemic for malaria, lymphatic filariasis and mansonellosis. Affected by repeat natural disasters, poverty and lack of adequate infrastructure, control of transmission within Haiti and prevention of dissemination of vector-borne pathogens to other regions is challenging. In this review we summarize some aspects concerning diseases caused by vector-borne pathogens in Haiti. Copyright © 2015 Elsevier Ltd. All rights reserved.

Repellency effect of forty-one essential oils against Aedes, Anopheles, and Culex mosquitoes.

PubMed

Amer, Abdelkrim; Mehlhorn, Heinz

2006-09-01

Since ancient times, plant products were used in various aspects. However, their use against pests decreased when chemical products became developed. Recently, concerns increased with respect to public health and environmental security requiring detection of natural products that may be used against insect pests. In this study, 41 plant extracts and 11 oil mixtures were evaluated against the yellow fever mosquito, Aedes aegypti (Linnaeus), the malaria vector, Anopheles stephensi (Liston), and the filariasis and encephalitis vector, Culex quinquefasciatus (Say) (Diptera: Culicidae) using the skin of human volunteers to find out the protection time and repellency. The five most effective oils were those of Litsea (Litsea cubeba), Cajeput (Melaleuca leucadendron), Niaouli (Melaleuca quinquenervia), Violet (Viola odorata), and Catnip (Nepeta cataria), which induced a protection time of 8 h at the maximum and a 100% repellency against all three species. This effect needs, however, a peculiar formulation to fix them on the human skin.

[Record of epidemiologically important Culicidae in the rural area of Manaus, Amazonas].

PubMed

Barbosa, Maria das Graças Vale; Fé, Nelson Ferreira; Marcião, Alexandre Herculano Ribera; Silva, Ana Paula Thomé da; Monteiro, Wuelton Marcelo; Guerra, Marcus Vinitius de Farias; Guerra, Jorge Augusto de Oliveira

2008-01-01

The biodiversity of the Amazon region includes many species of arthropod vectors in different ecotopes, thus enabling occurrences of diseases like malaria, filariasis and arbovirosis. From August 2001 to July 2002, we gathered culicids from inside homes, from areas surrounding these homes and from forested areas of the São João Community, in the rural zone of Manaus, State of Amazonas. 1240 specimens were collected, belonging to the Culicinae (99%) and Anophelinae (1%) subfamilies, with 50 species. The Culicini tribe clearly predominated, with 904 specimens (72.9%), and the species Culex usquatus (22.6%) and Culex quinquefasciatus (17.7%) were prominent. Out of the total number of culicids, 1,077 (86.9%) were caught in the forests, 101 (8.1%) in the areas surrounding homes and 62 (5%) inside homes. Forests were the ecotope that presented the highest species diversity. The presence of Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus janthinomys and other proven or potential vectors was recorded.

Introduction to the symposium Global Perspective on the Culex pipiens Complex in the 21st century: The Interrelationship of Culex pipiens, quinquefasciatus, molestus and others.

PubMed

Linthicum, Kenneth J

2012-12-01

Mosquitoes in the Culex pipiens Complex, including Culex pipiens, Cx. quinquefasciatus, and Cx. molestus, are important pest species and vectors of human and animal diseases throughout the world's tropical, temperate, and Holarctic regions. Diseases transmitted by member of the Pipiens Complex include: St. Louis encephalitis and West Nile virus in North America, West Nile virus on several other continents, Rift Valley fever in Africa, lymphatic filariasis caused by Wuchereria bancrofti in the tropics, and Dirofilaria immitis globally. Here and in the following 14 papers, 3 abstracts and a summary paper are the proceedings of a symposium that gathered many of the world's experts on the Pipiens Complex to explore the current state of knowledge of the taxa. Information presented at the symposium will improve our knowledge of important members of the complex and enhance our ability to conduct efficient surveillance and efficacious control strategies. A background on previous discussions on the Pipiens Complex, and a brief description of current symposium contributors and their topics are discussed.

Synthesis, crystal structure and larvicidal activity of novel diamide derivatives against Culex pipiens.

PubMed

Wu, Rui; Zhu, Cong; Du, Xiu-Jiang; Xiong, Li-Xia; Yu, Shu-Jing; Liu, Xing-Hai; Li, Zheng-Ming; Zhao, Wei-Guang

2012-09-11

Culex is an important mosquito as vectors for the transmission of serious diseases, such as filariasis, West Nile virus, dengue, yellow fever, chikungunya and other encephalitides. Nearly one billion people in the developing countries are at risk. In order to discover new bioactive molecules and pesticides acting on mosquito, we designed active amide structure and synthesized a series of novel diamide derivatives. A series of novel diamide derivatives were designed and synthesized. Their structures were characterized by 1 H NMR, FTIR and HRMS. The single crystal structure of compound 6n was determined to further elucidate the structure. Biological activities of these compounds were tested. Most of them exhibited higher mosquito larvicidal activity. Especially compound 6r displayed relatively good activity to reach 70% at 2 μg/mL. A practical synthetic route to amide derivatives by the reaction of amide with another acid is presented. This study suggests that the diamide derivatives exhibited good effective against mosquito.

Probing intermolecular interactions in a diethylcarbamazine citrate salt by fast MAS 1H solid-state NMR spectroscopy and GIPAW calculations.

PubMed

Venâncio, Tiago; Oliveira, Lyege Magalhaes; Ellena, Javier; Boechat, Nubia; Brown, Steven P

2017-10-01

Fast magic-angle spinning (MAS) NMR is used to probe intermolecular interactions in a diethylcarbamazine salt, that is widely used as a treatment against adult worms of Wuchereria bancrofti which cause a common disease in tropical countries named filariasis. Specifically, a dihydrogen citrate salt that has improved thermal stability and solubility as compared to the free form is studied. One-dimensional 1 H, 13 C and 15 N and two-dimensional 1 H- 13 C and 14 N- 1 H heteronuclear correlation NMR experiments under moderate and fast MAS together with GIPAW (CASTEP) calculations enable the assignment of the 1 H, 13 C and 14 N/ 15 N resonances. A two-dimensional 1 H- 1 H double-quantum (DQ) -single-quantum (SQ) MAS spectrum recorded with BaBa recoupling at 60kHz MAS identifies specific proton-proton proximities associated with citrate-citrate and citrate-diethylcarbamazine intermolecular interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of the mdr-1 Gene in Patients Co-Infected with Onchocerca volvulus and Loa loa Who Experienced a Post-Ivermectin Serious Adverse Event

PubMed Central

Bourguinat, Catherine; Kamgno, Joseph; Boussinesq, Michel; Mackenzie, Charles D.; Prichard, Roger K.; Geary, Timothy G.

2010-01-01

Ivermectin (IVM) is exceptionally safe in humans, and is used for mass treatment of onchocerciasis and lymphatic filariasis. However, cases of encephalopathy, sometimes fatal, have been reported in a small number of individuals who harbored large numbers of Loa loa microfilariae (mf). A loss-of-function mutation in the mdr-1 gene in some dog breeds and in mice leads to accumulation of the drug in the brain, causing coma and death. This hypothesis was tested in four individuals from Cameroon who experienced a post-IVM serious adverse event (SAE) and in nine non-SAE matched controls. No loss-of-function mutation was detected in mdr-1 in any subject. However, haplotypes, associated with altered drug disposition, were present as homozygotes in two of the SAE patients (50%), but absent as homozygotes in the controls (0%). An association of high Loa mf load and a genetic predisposition to altered IVM distribution could be involved in IVM SAEs. PMID:20595473

Semi-Quantitative Scoring of an Immunochromatographic Test for Circulating Filarial Antigen

PubMed Central

Chesnais, Cédric B.; Missamou, François; Pion, Sébastien D. S.; Bopda, Jean; Louya, Frédéric; Majewski, Andrew C.; Weil, Gary J.; Boussinesq, Michel

2013-01-01

The value of a semi-quantitative scoring of the filarial antigen test (Binax Now Filariasis card test, ICT) results was evaluated during a field survey in the Republic of Congo. One hundred and thirty-four (134) of 774 tests (17.3%) were clearly positive and were scored 1, 2, or 3; and 11 (1.4%) had questionable results. Wuchereria bancrofti microfilariae (mf) were detected in 41 of those 133 individuals with an ICT test score ≥ 1 who also had a night blood smear; none of the 11 individuals with questionable ICT results harbored night mf. Cuzick's test showed a significant trend for higher microfilarial densities in groups with higher ICT scores (P < 0.001). The ICT scores were also significantly correlated with blood mf counts. Because filarial antigen levels provide an indication of adult worm infection intensity, our results suggest that semi-quantitative reading of the ICT may be useful for grading the intensity of filarial infections in individuals and populations. PMID:24019435

Identification and prioritization of novel anti-Wolbachia chemotypes from screening a 10,000-compound diversity library

PubMed Central

Johnston, Kelly L.; Cook, Darren A. N.; Berry, Neil G.; David Hong, W.; Clare, Rachel H.; Goddard, Megan; Ford, Louise; Nixon, Gemma L.; O’Neill, Paul M.; Ward, Stephen A.; Taylor, Mark J.

2017-01-01

Lymphatic filariasis and onchocerciasis are two important neglected tropical diseases (NTDs) that cause severe disability. Control efforts are hindered by the lack of a safe macrofilaricidal drug. Targeting the Wolbachia bacterial endosymbionts in these parasites with doxycycline leads to a macrofilaricidal outcome, but protracted treatment regimens and contraindications restrict its widespread implementation. The Anti-Wolbachia consortium aims to develop improved anti-Wolbachia drugs to overcome these barriers. We describe the first screening of a large, diverse compound library against Wolbachia. This whole-organism screen, streamlined to reduce bottlenecks, produced a hit rate of 0.5%. Chemoinformatic analysis of the top 50 hits led to the identification of six structurally diverse chemotypes, the disclosure of which could offer interesting avenues of investigation to other researchers active in this field. An example of hit-to-lead optimization is described to further demonstrate the potential of developing these high-quality hit series as safe, efficacious, and selective anti-Wolbachia macrofilaricides. PMID:28959730

Compulsive masturbation and chronic penile lymphedema.

PubMed

Calabrò, Rocco Salvatore; Galì, Alessandro; Marino, Silvia; Bramanti, Placido

2012-06-01

Chronic penile lymphedema arises from the abnormal retention of lymphatic fluid in the subcutaneous tissues and may be secondary to local and systemic medical conditions such as sexually transmitted diseases, filariasis, malignancy, local radiotherapy, and surgery. This case report aims to consider compulsive masturbation as a possible cause of chronic penile edema. A 40-year-old man was referred to our institute for behavioral disturbance, including compulsive masturbation. Neuropsychiatric evaluation showed moderate mental retardation, mild dysarthria and limb incoordination, anxiety, depressed mood, and impulse dyscontrol. Brain MRI pointed out diffuse white matter lesions. Urogenital examination revealed an uncircumcised penis with non-tender edema of the shaft and prepuce with areas of lichenification. Since the most common local and systemic causes of edema were excluded, chronic penile edema due to compulsive masturbation was diagnosed and the compulsive behavior treated with an antidepressant and low-dose neuroleptics. Compulsive masturbation should be taken into account when counselling patients with penile edema.

Preventive chemotherapy in human helminthiasis: theoretical and operational aspects

PubMed Central

Chitsulo, L.; Engels, D.; Savioli, L.

2017-01-01

Preventive chemotherapy (PC), the large-scale distribution of anthelminthic drugs to population groups at risk, is the core intervention recommended by the WHO for reducing morbidity and transmission of the four main helminth infections, namely lymphatic filariasis, onchocerciasis, schistosomiasis and soil-transmitted helminthiasis. The strategy is widely implemented worldwide but its general theoretical foundations have not been described so far in a comprehensive and cohesive manner. Starting from the information available on the biological and epidemiological characteristics of helminth infections, as well as from the experience generated by disease control and elimination interventions across the world, we extrapolate the fundamentals and synthesise the principles that regulate PC and justify its implementation as a sound and essential public health intervention. The outline of the theoretical aspects of PC contributes to a thorough understanding of the different facets of this strategy and helps comprehend opportunities and limits of control and elimination interventions directed against helminth infections. PMID:22040463

Ancient horizontal transfers of retrotransposons between birds and ancestors of human pathogenic nematodes

PubMed Central

Suh, Alexander; Witt, Christopher C.; Menger, Juliana; Sadanandan, Keren R.; Podsiadlowski, Lars; Gerth, Michael; Weigert, Anne; McGuire, Jimmy A.; Mudge, Joann; Edwards, Scott V.; Rheindt, Frank E.

2016-01-01

Parasite host switches may trigger disease emergence, but prehistoric host ranges are often unknowable. Lymphatic filariasis and loiasis are major human diseases caused by the insect-borne filarial nematodes Brugia, Wuchereria and Loa. Here we show that the genomes of these nematodes and seven tropical bird lineages exclusively share a novel retrotransposon, AviRTE, resulting from horizontal transfer (HT). AviRTE subfamilies exhibit 83–99% nucleotide identity between genomes, and their phylogenetic distribution, paleobiogeography and invasion times suggest that HTs involved filarial nematodes. The HTs between bird and nematode genomes took place in two pantropical waves, >25–22 million years ago (Myr ago) involving the Brugia/Wuchereria lineage and >20–17 Myr ago involving the Loa lineage. Contrary to the expectation from the mammal-dominated host range of filarial nematodes, we hypothesize that these major human pathogens may have independently evolved from bird endoparasites that formerly infected the global breadth of avian biodiversity. PMID:27097561

Mucocutaneous manifestations of helminth infections: Trematodes and cestodes.

PubMed

Lupi, Omar; Downing, Christopher; Lee, Michael; Bravo, Francisco; Giglio, Patricia; Woc-Colburn, Laila; Tyring, Stephen K

2015-12-01

In the 21st century, despite increased international travel for vacation, work, and medical missions and immigration into the United States, there is little published in the dermatology literature regarding the cutaneous manifestations of helminth infections. It has been estimated that 20% to 70% of international travelers suffer from some travel-related health problem. Approximately 17% of travelers seek medical care because of cutaneous disorders, many related to infectious etiologies. This review will focus on cutaneous diseases caused by helminth infections. Part I of the review focused on nematode infections; part II will focus on trematode and cestode infections. Nematodes are roundworms that cause diseases with cutaneous manifestations, such as cutaneous larval migrans, onchocerciasis, filariasis, gnathostomiasis, loiasis, dracunculiasis, strongyloidiasis, ascariasis, streptocerciasis, dirofilariasis, and trichinosis. Tremadotes, also known as flukes, cause schistosomiasis, paragonimiasis, and fascioliasis. Cestodes (tapeworms) are flat, hermaphroditic parasites that cause diseases such as sparganosis, cysticercosis, and echinococcus. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Tropical environments, human activities, and the transmission of infectious diseases.

PubMed

Sattenspiel, L

2000-01-01

Throughout recent history, the tropical regions of the world have been affected more severely by infectious diseases than the temperate world. Much of the success of infectious diseases in that region is due to both biological and environmental factors that encourage high levels of biodiversity in hosts, vectors, and pathogens, and social factors that compromise efforts to control diseases. Several of these factors are described. Discussion then shifts to specific types of host-pathogen relationships. The most important of these in the tropics is the relationship between humans, a pathogen, and a vector that carries the pathogen from one human to another. Mosquitoes are the vector responsible for the transmission of many vector-borne human diseases. Characteristics of mosquito-human interactions are described, including cultural behaviors humans have developed that both increase the chances of transmission and help to limit that transmission. The transmission of water-borne diseases, fecal-oral transmission, zoonotic diseases, respiratory illnesses, and sexually transmitted diseases are also discussed. Attention is paid to how diseases with these modes of transmission differ in characteristics and importance in tropical human populations compared to those in temperate regions. Following this general discussion, three case studies are presented in some detail. The diseases chosen for the case studies include cholera, lymphatic filariasis, and dracunculiasis (guinea worm). These three case studies taken together provide examples of the diversity of human host-pathogen interactions as well as ways that human activities have both promoted their spread and helped to control them. The transmission of all three diseases is related to the nature and quality of water sources. The transmission of cholera, a water-borne disease, is related to sanitation practices, physical characteristics of the environment such as temperature and humidity, and modern shipping practices

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

Maternal influence on susceptibility of offspring to Brugia malayi infection in a murine model of filariasis.

PubMed

Rajan, T V; Bailis, J M; Yates, J A; Shultz, L D; Greiner, D L; Nelson, F K

1994-12-01

We have used the severe combined immunodeficient C.B-17-scid/scid mouse to investigate the influences of maternal immune status and parasite burden on the susceptibility (or resistance) of offspring to infection with the human filarial parasite, Brugia malayi. C.B-17-scid/scid mice are permissive for infection while immunocompetent C.B-17(-)+/+ mice are uniformly resistant. Reciprocal matings of C.B-17-scid/scid and C.B-17(-)+/+ mice were performed. The C.B-17-scid/scid females were either naive or infected with Brugia malayi. The resulting immunocompetent C.B-17-scid/+ and C.B-17(-)+/scid progeny were challenged at weaning with an intraperitoneal injection of Brugia malayi third stage larvae known to produce patent infection in > 95% of C.B-17-scid/scid mice. We observed that 40.0%l (34/85) of the immunocompetent offspring of C.B-17-scid/scid females x C.B-17(-)+/+ males were permissive for the growth and development of Brugia malayi larvae to adults. No difference was observed in susceptibility to infection between the progeny of infected or uninfected C.B-17-scid/scid mothers mated with C.B-17(-)+/+ fathers, arguing against acquired immunological tolerance to the parasite in the former. In marked contrast, only 4.8% (2/42) of the heterozygous progeny of wild type C.B-17(-)+/+ females mated with C.B-17-scid/scid males were permissive. These observations document conversion of a 'resistant' phenotype to a 'susceptible' phenotype by manipulation of maternal immune status and provide clear evidence of maternal influence on offspring susceptibility to infection with Brugia malayi.

Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue.

PubMed

Arjunan, Naresh Kumar; Murugan, Kadarkarai; Rejeeth, Chandrababu; Madhiyazhagan, Pari; Barnard, Donald R

2012-03-01

A biological method was used to synthesize stable silver nanoparticles that were tested as mosquito larvicides against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Annona squamosa leaf broth (5%) reduced aqueous 1 mM AgNO₃ to stable silver nanoparticles with an average size of 450 nm. The structure and percentage of synthesized nanoparticles was characterized by using ultraviolet spectrophotometry, X-Ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy methods. The median lethal concentrations (LC₅₀) of silver nanoparticles that killed fourth instars of Ae. aegypti, Cx. quinquefasciatus, and An. stephensi were 0.30, 0.41, and 2.12 ppm, respectively. Adult longevity (days) in male and female mosquitoes exposed as larvae to 0.1 ppm silver nanoparticles was reduced by ~30% (p<0.05), whereas the number of eggs laid by females exposed as larvae to 0.1 ppm silver nanoparticles decreased by 36% (p<0.05).

Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue

USDA-ARS?s Scientific Manuscript database

A biological method was used to synthesize stable silver nanoparticles. The nanoparticles were tested as larvicides against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Annona squamosa leaf broth (5%) reduced aqueous AgNO3 to stable silver nanoparticles with average particle siz...

Point-of-Care Ultrasound Assessment of Tropical Infectious Diseases--A Review of Applications and Perspectives.

PubMed

Bélard, Sabine; Tamarozzi, Francesca; Bustinduy, Amaya L; Wallrauch, Claudia; Grobusch, Martin P; Kuhn, Walter; Brunetti, Enrico; Joekes, Elizabeth; Heller, Tom

2016-01-01

The development of good quality and affordable ultrasound machines has led to the establishment and implementation of numerous point-of-care ultrasound (POCUS) protocols in various medical disciplines. POCUS for major infectious diseases endemic in tropical regions has received less attention, despite its likely even more pronounced benefit for populations with limited access to imaging infrastructure. Focused assessment with sonography for HIV-associated TB (FASH) and echinococcosis (FASE) are the only two POCUS protocols for tropical infectious diseases, which have been formally investigated and which have been implemented in routine patient care today. This review collates the available evidence for FASH and FASE, and discusses sonographic experiences reported for urinary and intestinal schistosomiasis, lymphatic filariasis, viral hemorrhagic fevers, amebic liver abscess, and visceral leishmaniasis. Potential POCUS protocols are suggested and technical as well as training aspects in the context of resource-limited settings are reviewed. Using the focused approach for tropical infectious diseases will make ultrasound diagnosis available to patients who would otherwise have very limited or no access to medical imaging. © The American Society of Tropical Medicine and Hygiene.

Overcoming the challenges of drug discovery for neglected tropical diseases: the A·WOL experience.

PubMed

Johnston, Kelly L; Ford, Louise; Taylor, Mark J

2014-03-01

Neglected tropical diseases (NTDs) are a group of 17 diseases that typically affect poor people in tropical countries. Each has been neglected for decades in terms of funding, research, and policy, but the recent grouping of them into one unit, which can be targeted using integrated control measures, together with increased advocacy has helped to place them on the global health agenda. The World Health Organization has set ambitious goals to control or eliminate 10 NTDs by 2020 and launched a roadmap in January 2012 to guide this global plan. The result of the launch meeting, which brought together representatives from the pharmaceutical industry, donors, and politicians, was the London Declaration: a series of commitments to provide more drugs, research, and funds to achieve the 2020 goals. Drug discovery and development for these diseases are extremely challenging, and this article highlights these challenges in the context of the London Declaration, before focusing on an example of a drug discovery and development program for the NTDs onchocerciasis and lymphatic filariasis (the anti-Wolbachia consortium, A·WOL).

The Role of Natural Products in Drug Discovery and Development against Neglected Tropical Diseases.

PubMed

Cheuka, Peter Mubanga; Mayoka, Godfrey; Mutai, Peggoty; Chibale, Kelly

2016-12-31

Endemic in 149 tropical and subtropical countries, neglected tropical diseases (NTDs) affect more than 1 billion people annually, including 875 million children in developing economies. These diseases are also responsible for over 500,000 deaths per year and are characterized by long-term disability and severe pain. The impact of the combined NTDs closely rivals that of malaria and tuberculosis. Current treatment options are associated with various limitations including widespread drug resistance, severe adverse effects, lengthy treatment duration, unfavorable toxicity profiles, and complicated drug administration procedures. Natural products have been a valuable source of drug regimens that form the cornerstone of modern pharmaceutical care. In this review, we highlight the potential that remains untapped in natural products as drug leads for NTDs. We cover natural products from plant, marine, and microbial sources including natural-product-inspired semi-synthetic derivatives which have been evaluated against the various causative agents of NTDs. Our coverage is limited to four major NTDs which include human African trypanosomiasis (sleeping sickness), leishmaniasis, schistosomiasis and lymphatic filariasis.

Rapid mapping of schistosomiasis and other neglected tropical diseases in the context of integrated control programmes in Africa

PubMed Central

BROOKER, S.; KABATEREINE, N. B.; GYAPONG, J. O.; STOTHARD, J. R.; UTZINGER, J.

2009-01-01

SUMMARY There is growing interest and commitment to the control of schistosomiasis and other so-called neglected tropical diseases (NTDs). Resources for control are inevitably limited, necessitating assessment methods that can rapidly and accurately identify and map high-risk communities so that interventions can be targeted in a spatially-explicit and cost-effective manner. Here, we review progress made with (i) mapping schistosomiasis across Africa using available epidemiological data and more recently, climate-based risk prediction; (ii) the development and use of morbidity questionnaires for rapid identification of high-risk communities of urinary schistosomiasis; and (iii) innovative sampling-based approaches for intestinal schistosomiasis, using the lot quality assurance sampling technique. Experiences are also presented for the rapid mapping of other NTDs, including onchocerciasis, loiasis and lymphatic filariasis. Future directions for an integrated rapid mapping approach targeting multiple NTDs simultaneously are outlined, including potential challenges in developing an integrated survey tool. The lessons from the mapping of human helminth infections may also be relevant for the rapid mapping of malaria as its control efforts are intensified. PMID:19450373

Effect of lambda cyhalothrin and temephos on detoxification enzyme systems in Culex quinquefasciatus (Diptera: Culicidae).

PubMed

Muthusamy, R; Shivakumar, M S

2015-01-01

Mosquitoes serve as vector for transmitting diseases. Among mosquitoes, Culex quinquefasciatus transmits lymphatic filariasis, yellow fever Japanese encephalitis etc. Application of chemical insecticides is still the best option for vector control programmes. Continuous use of these chemicals on mosquito reduces its effects. The present study determined the baseline susceptibility of Cx. quinquefasciatus in response to λ-cyhalothrin and temephos treatments. In addition, the biochemical mechanisms and zymogram analysis involved in insecticide detoxification among larval mosquitoes were studied. The larval bioassay indicated high LC50 value for λ-cyhalothrin (0.1484ppm) as compared to temephos (0.01092ppm). While AChE assay showed increased activity in temephos treatments, glutathione reductase (GR) and esterase levels were increased at both the treatments. Esterase quantitative analysis revealed the expression of three bands at 43kDa, 67kDa and 245kDa. The findings suggest that insensitivity of AChE, esterase and high GR activity may play an important role in developing resistance to synthetic pyrethroid and organophosphate insecticides in Cx. quinquefasciatus population.

[Epidemiology and control of malaria in the Federal Islamic Republic of Comoros].

PubMed

Ouledi, A

1995-01-01

Malaria constitutes a major public health problem in the Federal Islamic Republic of Comoros. This problem is relatively recent from the historical point of view of the archipelago. It represents 15 to 30% of the hospitalization cases and 15 to 20% of the registered deaths in the pediatric services. The epidemiological data collected show that the characteristics of malaria transmission continue for the stable type; however, the epidemiological situation varies from one island to another. The principal vectors of malaria are Anopheles gambiae s.l. and A. funestus. Of the four parasitic species, P. falciparum remains the most dominant, as it is responsible for 95% of the paludal attacks. Important progress has been accomplished during the last several years in the fight against malaria in the Federal Islamic Republic of Comoros, with the elaboration of national politics (October 1992), a national strategy for an antivectorial fight (August 1993) and a practical guide for the treatment and prevention of malaria and filariasis (October 1993). These important achievements allow the establishment of more vigorous and better targeted future actions.

The Applications of Model-Based Geostatistics in Helminth Epidemiology and Control

PubMed Central

Magalhães, Ricardo J. Soares; Clements, Archie C.A.; Patil, Anand P.; Gething, Peter W.; Brooker, Simon

2011-01-01

Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes. PMID:21295680

The applications of model-based geostatistics in helminth epidemiology and control.

PubMed

Magalhães, Ricardo J Soares; Clements, Archie C A; Patil, Anand P; Gething, Peter W; Brooker, Simon

2011-01-01

Funding agencies are dedicating substantial resources to tackle helminth infections. Reliable maps of the distribution of helminth infection can assist these efforts by targeting control resources to areas of greatest need. The ability to define the distribution of infection at regional, national and subnational levels has been enhanced greatly by the increased availability of good quality survey data and the use of model-based geostatistics (MBG), enabling spatial prediction in unsampled locations. A major advantage of MBG risk mapping approaches is that they provide a flexible statistical platform for handling and representing different sources of uncertainty, providing plausible and robust information on the spatial distribution of infections to inform the design and implementation of control programmes. Focussing on schistosomiasis and soil-transmitted helminthiasis, with additional examples for lymphatic filariasis and onchocerciasis, we review the progress made to date with the application of MBG tools in large-scale, real-world control programmes and propose a general framework for their application to inform integrative spatial planning of helminth disease control programmes. Copyright © 2011 Elsevier Ltd. All rights reserved.

A Laboratory-Based Surveillance System for Wuchereria bancrofti in Togo: A Practical Model for Resource-Poor Settings

PubMed Central

Mathieu, Els; Dorkenoo, Ameyo; Otogbe, Felix K. J.; Budge, Philip J.; Sodahlon, Yao K.

2011-01-01

One goal of the Global Program to Eliminate Lymphatic Filariasis (GAELF) is interruption of disease transmission through annual mass drug administration (MDA) in areas where LF prevalence is greater than 1%. After MDAs are completed, the World Health Organization (WHO) recommends a period of passive surveillance before final certification of LF elimination is achieved. Guidelines for such a surveillance system have yet to be developed. This paper describes a surveillance system launched in Togo in 2006. The system uses existing laboratories with technicians on call at night who, among other activities, prepare nocturnal thick blood smears for malaria diagnosis that can also be used for LF diagnosis. During its first 2 years (2006–2007), the system provided geographically disperse sampling nationwide, and 1 of 750 people residing in Togo was tested. Over the same period, the system detected two cases of LF, both from areas previously considered non-endemic. This system could be a cost-effective, sustainable model for WHO-mandated passive surveillance after cessation of MDA. PMID:21633038

Epidemiology of subperiodic Wuchereria bancrofti infection in the Nicobar Islands, India.

PubMed

Tewari, S C; Hiriyan, J; Reuben, R

1995-01-01

Diurnally subperiodic filariasis due to Wuchereria bancrofti has been reported from tribal populations in the Nancowry group of islands in the Andaman and Nicobar Islands, India. This was confirmed in a survey carried out during the monsoon season in 1993. Microfilariae were detected in the peripheral blood throughout a 24 h period with a peak at 18:00. The microfilaria (mf) rate ranged from 1.2% to 18.7%, with a low disease rate (mean = 1.9%). Incidence of mf was low in children less than 10 years old (3.5%), but increased with increasing age. Culex (Culex) quinquefasciatus was present at a very low density. Aedes (Finlaya) niveus and Aedes (Stegomyia) malayensis were the only species commonly biting man. The former was incriminated as a vector, and found naturally infected with W. bancrofti (infection and infectivity rates 1.1% and 0.9% respectively). After experimental feeding on donors, W. bancrofti developed to L3 stage larvae in A. niveus but failed to develop in A. malayensis and A. aegypti.

Plant extracts as potential mosquito larvicides

PubMed Central

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-01-01

Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed. PMID:22771587

Point-of-Care Ultrasound Assessment of Tropical Infectious Diseases—A Review of Applications and Perspectives

PubMed Central

Bélard, Sabine; Tamarozzi, Francesca; Bustinduy, Amaya L.; Wallrauch, Claudia; Grobusch, Martin P.; Kuhn, Walter; Brunetti, Enrico; Joekes, Elizabeth; Heller, Tom

2016-01-01

The development of good quality and affordable ultrasound machines has led to the establishment and implementation of numerous point-of-care ultrasound (POCUS) protocols in various medical disciplines. POCUS for major infectious diseases endemic in tropical regions has received less attention, despite its likely even more pronounced benefit for populations with limited access to imaging infrastructure. Focused assessment with sonography for HIV-associated TB (FASH) and echinococcosis (FASE) are the only two POCUS protocols for tropical infectious diseases, which have been formally investigated and which have been implemented in routine patient care today. This review collates the available evidence for FASH and FASE, and discusses sonographic experiences reported for urinary and intestinal schistosomiasis, lymphatic filariasis, viral hemorrhagic fevers, amebic liver abscess, and visceral leishmaniasis. Potential POCUS protocols are suggested and technical as well as training aspects in the context of resource-limited settings are reviewed. Using the focused approach for tropical infectious diseases will make ultrasound diagnosis available to patients who would otherwise have very limited or no access to medical imaging. PMID:26416111

History of Human Parasitology

PubMed Central

Cox, F. E. G.

2002-01-01

Humans are hosts to nearly 300 species of parasitic worms and over 70 species of protozoa, some derived from our primate ancestors and some acquired from the animals we have domesticated or come in contact with during our relatively short history on Earth. Our knowledge of parasitic infections extends into antiquity, and descriptions of parasites and parasitic infections are found in the earliest writings and have been confirmed by the finding of parasites in archaeological material. The systematic study of parasites began with the rejection of the theory of spontaneous generation and the promulgation of the germ theory. Thereafter, the history of human parasitology proceeded along two lines, the discovery of a parasite and its subsequent association with disease and the recognition of a disease and the subsequent discovery that it was caused by a parasite. This review is concerned with the major helminth and protozoan infections of humans: ascariasis, trichinosis, strongyloidiasis, dracunculiasis, lymphatic filariasis, loasis, onchocerciasis, schistosomiasis, cestodiasis, paragonimiasis, clonorchiasis, opisthorchiasis, amoebiasis, giardiasis, African trypanosomiasis, South American trypanosomiasis, leishmaniasis, malaria, toxoplasmosis, cryptosporidiosis, cyclosporiasis, and microsporidiosis. PMID:12364371

Lymphatic filarial species differentiation using evolutionarily modified tandem repeats: generation of new genetic markers.

PubMed

Sakthidevi, Moorthy; Murugan, Vadivel; Hoti, Sugeerappa Laxmanappa; Kaliraj, Perumal

2010-05-01

Polymerase chain reaction based methods are promising tools for the monitoring and evaluation of the Global Program for the Elimination of Lymphatic Filariasis. The currently available PCR methods do not differentiate the DNA of Wuchereria bancrofti or Brugia malayi by a single PCR and hence are cumbersome. Therefore, we designed a single step PCR strategy for differentiating Bancroftian infection from Brugian infection based on a newly identified gene from the W. bancrofti genome, abundant larval transcript-2 (alt-2), which is abundantly expressed. The difference in PCR product sizes generated from the presence or absence of evolutionarily altered tandem repeats in alt-2 intron-3 differentiated W. bancrofti from B. malayi. The analysis was performed on the genomic DNA of microfilariae from a number of patient blood samples or microfilariae positive slides from different Indian geographical regions. The assay gave consistent results, differentiating the two filarial parasite species accurately. This alt-2 intron-3 based PCR assay can be a potential tool for the diagnosis and differentiation of co-infections by lymphatic filarial parasites. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Plant extracts as potential mosquito larvicides.

PubMed

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-05-01

Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed.

Chemical composition and insecticidal activity of the essential oil from Helichrysum faradifani endemic to Madagascar.

PubMed

Benelli, Giovanni; Pavela, Roman; Rakotosaona, Rianasoambolanoro; Randrianarivo, Emmanuel; Nicoletti, Marcello; Maggi, Filippo

2017-11-03

Helichrysum faradifani (Asteraceae) is a perennial shrub growing in rocky and sandy places of Madagascar. The plant is used in the Malagasy traditional medicine as a wound-healing agent, disinfectant and for the treatment of syphilis, diarrhea, cough and headache. In the present work, we analysed the chemical composition of the essential oil distilled from the aerial parts of H. faradifani by GC-MS and evaluated its insecticidal activity against 2nd, 3rd and 4th instar larvae of the lymphatic filariasis vector Culex quinquefasciatus by acute toxicity assays. The most sensitive were 2nd instar (LC 50  = 85.7 μL L -1 ) larvae. For the 3rd and 4th instar larvae, the estimated LC 50 were 156.8 and 134.1 μL L -1 , respectively. Monoterpene hydrocarbons (51.6%) were the major fraction of the essential oil, with the bicyclic α-fenchene (35.6%) as the predominant component. Sesquiterpene hydrocarbons (34.0%) were the second major group characterising the oil, with γ-curcumene (17.7%) as the most abundant component.

Aminoacyl-tRNA synthetases as drug targets in eukaryotic parasites☆

PubMed Central

Pham, James S.; Dawson, Karen L.; Jackson, Katherine E.; Lim, Erin E.; Pasaje, Charisse Flerida A.; Turner, Kelsey E.C.; Ralph, Stuart A.

2013-01-01

Aminoacyl-tRNA synthetases are central enzymes in protein translation, providing the charged tRNAs needed for appropriate construction of peptide chains. These enzymes have long been pursued as drug targets in bacteria and fungi, but the past decade has seen considerable research on aminoacyl-tRNA synthetases in eukaryotic parasites. Existing inhibitors of bacterial tRNA synthetases have been adapted for parasite use, novel inhibitors have been developed against parasite enzymes, and tRNA synthetases have been identified as the targets for compounds in use or development as antiparasitic drugs. Crystal structures have now been solved for many parasite tRNA synthetases, and opportunities for selective inhibition are becoming apparent. For different biological reasons, tRNA synthetases appear to be promising drug targets against parasites as diverse as Plasmodium (causative agent of malaria), Brugia (causative agent of lymphatic filariasis), and Trypanosoma (causative agents of Chagas disease and human African trypanosomiasis). Here we review recent developments in drug discovery and target characterisation for parasite aminoacyl-tRNA synthetases. PMID:24596663

Eotaxin-1 is involved in parasite clearance during chronic filarial infection.

PubMed

Gentil, K; Lentz, C S; Rai, R; Muhsin, M; Kamath, A D; Mutluer, O; Specht, S; Hübner, M P; Hoerauf, A

2014-02-01

Eosinophil migration as key feature of helminth infection is increased during infection with filarial nematodes. In a mouse model of filariasis, we investigated the role of the eosinophil-attracting chemokine Eotaxin-1 on disease outcome. BALB/c and Eotaxin-1(-/-) mice were infected with the rodent filaria Litomosoides sigmodontis, and parasitic parameters, cellular migration to the site of infection, and cellular responsiveness were investigated. We found increased parasite survival but unaffected eosinophil migration to the site of infection in Eotaxin-1(-/-) mice. Expression of CD80 and CD86 was reduced on eosinophils from Eotaxin-1(-/-) mice after in vitro TLR2 stimulation and exposure to filarial antigen, respectively, suggesting a potential reduced activation state of eosinophils in Eotaxin-1 deficient mice. We further demonstrated that macrophages from Eotaxin-1(-/-) mice produce decreased amounts of IL-6 in vitro, a cytokine found to be associated with parasite containment, suggesting possible mechanisms by which Eotaxin-1 regulates activation of inflammatory cells and thus parasite survival. © 2013 John Wiley & Sons Ltd.

Preventive chemotherapy in human helminthiasis: theoretical and operational aspects.

PubMed

Gabrielli, A-F; Montresor, A; Chitsulo, L; Engels, D; Savioli, L

2011-12-01

Preventive chemotherapy (PC), the large-scale distribution of anthelminthic drugs to population groups at risk, is the core intervention recommended by the WHO for reducing morbidity and transmission of the four main helminth infections, namely lymphatic filariasis, onchocerciasis, schistosomiasis and soil-transmitted helminthiasis. The strategy is widely implemented worldwide but its general theoretical foundations have not been described so far in a comprehensive and cohesive manner. Starting from the information available on the biological and epidemiological characteristics of helminth infections, as well as from the experience generated by disease control and elimination interventions across the world, we extrapolate the fundamentals and synthesise the principles that regulate PC and justify its implementation as a sound and essential public health intervention. The outline of the theoretical aspects of PC contributes to a thorough understanding of the different facets of this strategy and helps comprehend opportunities and limits of control and elimination interventions directed against helminth infections. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

[Challenge and strategy of prevention and control of important parasitic diseases under the Belt and Road Initiative].

PubMed

Chun-Li, Cao; Jia-Gang, Guo

2018-04-17

China was once a country with the heaviest burden of parasitic diseases. Under the leadership of the Communist Party and national authority, after more than 60 years' efforts of prevention and control, the remarkable results have been achieved in China. However, affected by the social and economic development and environmental changes, the prevention and control of parasitic diseases, especially imported parasitic diseases, are facing new challenges, and the parasitic diseases, such as malaria, schistosomiasis, leishmaniasis, filariasis and trypanosomiasis, appear increasingly. With the development of the Belt and Road Initiative, the transmission risks of these diseases are more increased. The purpose of this paper is to describe the experience and results of parasitic disease prevention and control in China, understand the present parasitic disease epidemic situation of the Belt and Road Initiative related countries, analyze the transmission risks of important parasitic diseases, and present some relevant suggestions, so as to provide the evidence for the health administrative department formulating the prevention and control strategies of such parasitic diseases timely and effectively.

History of human parasitology.

PubMed

Cox, F E G

2002-10-01

Humans are hosts to nearly 300 species of parasitic worms and over 70 species of protozoa, some derived from our primate ancestors and some acquired from the animals we have domesticated or come in contact with during our relatively short history on Earth. Our knowledge of parasitic infections extends into antiquity, and descriptions of parasites and parasitic infections are found in the earliest writings and have been confirmed by the finding of parasites in archaeological material. The systematic study of parasites began with the rejection of the theory of spontaneous generation and the promulgation of the germ theory. Thereafter, the history of human parasitology proceeded along two lines, the discovery of a parasite and its subsequent association with disease and the recognition of a disease and the subsequent discovery that it was caused by a parasite. This review is concerned with the major helminth and protozoan infections of humans: ascariasis, trichinosis, strongyloidiasis, dracunculiasis, lymphatic filariasis, loasis, onchocerciasis, schistosomiasis, cestodiasis, paragonimiasis, clonorchiasis, opisthorchiasis, amoebiasis, giardiasis, African trypanosomiasis, South American trypanosomiasis, leishmaniasis, malaria, toxoplasmosis, cryptosporidiosis, cyclosporiasis, and microsporidiosis.

Is there a risk of filarial infection during long-term missions in Haiti?

PubMed

Weitzel, Thomas; Rosas, Reinaldo; Fica, Alberto; Dabanch, Jeannette; Polanco, Myriam; Egaña, Alicia; Triantafilo, Vjera; Pfarr, Kenneth; Hoerauf, Achim; Reiter-Owona, Ingrid

2016-01-01

Haiti has the highest prevalence of lymphatic filariasis (Wuchereria bancrofti) in the Western Hemisphere. Still, the risk of filarial infection for long-term visitors such as humanitarian aid workers or military personnel is uncertain. The presented study analyzed the exposure to W. bancrofti in Chilean participants of the UN Stabilization Mission in Haiti (MINUSTAH) in 2011. Blood samples collected from 531 participants were screened for antifilarial antibodies by IgG ELISA, and, if positive, analyzed by immunofluorescence assay (IFA), IgG4 ELISA, Real-Time PCR, and circulating filarial antigen (CFA) card test. ELISA screening was positive in 10 cases. Seroconversion occurred in only two cases (0.38%) based on ELISA values determined in samples taken before and after deployment. Positive IgG ELISA values could not be confirmed by IFA and IgG4 ELISA. Real-Time PCR and CFA testing did not reveal the presence of filaria. Our data indicate that in the examined cohort of MINUSTAH participants in 2011, the risk of filarial exposure or infection was low. Copyright © 2015 Elsevier Ltd. All rights reserved.

Exploring the Potential of Flubendazole in Filariasis Control: Evaluation of the Systemic Exposure for Different Pharmaceutical Preparations

PubMed Central

Ceballos, Laura; Mackenzie, Charles; Geary, Timothy; Alvarez, Luis; Lanusse, Carlos

2014-01-01

The goal of elimination of the human filariases would benefit greatly from the use of a macrofilaricidal agent. In vivo trials in humans and many experimental animal models suggest that flubendazole (FLBZ) is a highly efficacious macrofilaricide. However, since serious injection site reactions were reported in humans after parenteral FLBZ administration, the search for alternative pharmaceutical strategies to improve the systemic availability of FLBZ and its metabolites has acquired urgency in both human and veterinary medicine. The goal of the current work was to compare the systemic exposure of FLBZ formulated as either an aqueous hydroxypropyl-β-cyclodextrin (CD) or aqueous carboxymethyl cellulose (CMC) suspension or a Tween 80-based formulation (TWEEN) in rats and jirds (Meriones unguiculatus). Healthy animals of both species were allocated into four experimental groups of 44 animals each: FLBZ-CDoral and FLBZ-CDsc, treated with the FLBZ-CD formulation by the oral or subcutaneous routes, respectively; FLBZ-TWEENsc, dosed subcutaneously with the FLBZ-TWEEN formulation; and FLBZ-CMCoral, treated orally with the FLBZ suspension. The FLBZ dose was 5 mg/kg. FLBZ and its hydrolyzed (H-FLBZ) and reduced (R-FLBZ) metabolites were recovered in plasma samples collected from rats and jirds treated with the different FLBZ formulations. In both species, FLBZ parent drug was the main analyte recovered in the bloodstream. In rats, FLBZ systemic exposure (AUC0-LOQ) was significantly (P<0.05) higher after the FLBZ-CD treatments, both oral (4.8±0.9 µg.h/mL) and subcutaneous (7.3±0.6 µg.h/mL), compared to that observed after oral administration of FLBZ-CMC suspension (0.93±0.2 µg.h/mL). The same differences were observed in jirds. In both species, parenteral administration of FLBZ-TWEEN did not improve the systemic availability of FLBZ compared to FLBZ-CDoral treatment. In conclusion, formulation approaches that enhance the availability of flubendazole in the rat and jird may have therapeutic implications for a drug with poor or erratic bioavailability. PMID:24874646

Some considerations relating to the role of Culex pipiens fatigans Wiedemann in the transmission of human filariasis.

PubMed

MATTINGLY, P F

1962-01-01

This paper is concerned mainly with the relationship between microfilarial periodicity and vector periodicity. The so-called "non-periodic" Pacific form of Wuchereria bancrofti in fact shows a well-marked and relatively constant periodicity. The amplitude of this periodicity is low, which may account for the difficulty of detecting it in small clinical samples. The periodicity is well adapted to the biting cycle of Aëdes polynesiensis, though less so than that of the "semi-periodic" Brugia malayi to forest Mansonioides. Microfilarial periodicity is discussed in the light of recent work on circadian rhythms in other animals and it is suggested that certain possibilities have been given insufficient weight. The use of the term "migration" to describe microfilarial translocation within the host may have given rise to misunderstanding but it is in good agreement with current concepts of migration. Recent work suggests some behavioural heterogeneity in Culex fatigans which could render it a useful mosquito for elucidating certain important but little-understood problems.

Community Attitudes toward Mass Drug Administration for Control and Elimination of Neglected Tropical Diseases after the 2014 Outbreak of Ebola Virus Disease in Lofa County, Liberia

PubMed Central

Bogus, Joshua; Gankpala, Lincoln; Fischer, Kerstin; Krentel, Alison; Weil, Gary J.; Fischer, Peter U.; Kollie, Karsor; Bolay, Fatorma K.

2016-01-01

The recent outbreak of Ebola virus disease (EVD) interrupted mass drug administration (MDA) programs to control and eliminate neglected tropical diseases in Liberia. MDA programs treat entire communities with medication regardless of infection status to interrupt transmission and eliminate lymphatic filariasis and onchocerciasis. Following reports of hostilities toward health workers and fear that they might be spreading EVD, it was important to determine whether attitudes toward MDA might have changed after the outbreak. We surveyed 140 community leaders from 32 villages in Lofa County, Liberia, that had previously participated in MDA and are located in an area that was an early epicenter of the EVD outbreak. Survey respondents reported a high degree of community trust in the MDA program, and 97% thought their communities were ready to resume MDA. However, respondents predicted that fewer people would comply with MDA after the EVD epidemic than before. The survey also uncovered fears in the community that EVD and MDA might be linked. Respondents suggested that MDA programs emphasize to people that the medications are identical to those previously distributed and that MDA programs have nothing to do with EVD. PMID:26666700

Community Attitudes Toward Mass Drug Administration for Control and Elimination of Neglected Tropical Diseases After the 2014 Outbreak of Ebola Virus Disease in Lofa County, Liberia.

PubMed

Bogus, Joshua; Gankpala, Lincoln; Fischer, Kerstin; Krentel, Alison; Weil, Gary J; Fischer, Peter U; Kollie, Karsor; Bolay, Fatorma K

2016-03-01

The recent outbreak of Ebola virus disease (EVD) interrupted mass drug administration (MDA) programs to control and eliminate neglected tropical diseases in Liberia. MDA programs treat entire communities with medication regardless of infection status to interrupt transmission and eliminate lymphatic filariasis and onchocerciasis. Following reports of hostilities toward health workers and fear that they might be spreading EVD, it was important to determine whether attitudes toward MDA might have changed after the outbreak. We surveyed 140 community leaders from 32 villages in Lofa County, Liberia, that had previously participated in MDA and are located in an area that was an early epicenter of the EVD outbreak. Survey respondents reported a high degree of community trust in the MDA program, and 97% thought their communities were ready to resume MDA. However, respondents predicted that fewer people would comply with MDA after the EVD epidemic than before. The survey also uncovered fears in the community that EVD and MDA might be linked. Respondents suggested that MDA programs emphasize to people that the medications are identical to those previously distributed and that MDA programs have nothing to do with EVD. © The American Society of Tropical Medicine and Hygiene.

[Brazilian biomedical publications in the international scientific literature. Endemic communicable diseases].

PubMed

de Souza, C A; Lima, J A; Schmitt, C M; Piegas, M H; Peixinho, A; Schmidt, A; de Lemos, A A

1986-01-01

The number of Brazilian periodicals listed in the Index Medicus dropped from 70 in 1964 to 15 in 1983, or 78%, while the total number of listed periodicals from other countries fell only 11%. The total number of articles published in Brazil on Chagas' disease, schistosomiasis, leishmaniasis, leprosy, malaria, and filariasis, and listed in the Index Medicus did not change significantly between 1965 and 1982, because, with the exception of the journal O Hospital, the Brazilian periodicals that published 74% of all articles on those diseases remained listed throughout the period considered. The predominant subjects in articles on endemic diseases were Chagas' disease and schistosomiasis, and in the later years there was a tendency to index more articles on basic than on applied research. The number of articles on Chagas' disease published by Brazilian authors directly in foreign journals increased considerably during the latter decade. Analysis of all the data together suggests that the developed countries select a specific portion of the Brazilian output of biomedical literature--which is kept listed in secondary and international publications or published directly in foreign journals--while another portion of the same output gradually loses visibility on the international scene.

No case of Guinea worm. Just because governments like the United States and Japan, private organizations, corporations, and particularly the leaders and the villagers and afflicted countries have cooperated.

PubMed

Carter, J

1998-01-01

Collaboration among governments, private organizations, the World Bank, UN agencies, corporations, and the leaders and villagers of afflicted countries is producing substantial progress toward global eradication of many parasitic diseases. For example, there are now less than 100,000 cases of Guinea worm in the world--a 98% reduction. Strategies to prevent villagers from drinking infested water have included drilling deep wells, putting a nontoxic larvicide in the water, and straining the water through cloth filters. Both the larvicide and filters were provided free of charge to the eradication effort by US corporations. Similarly, a pharmaceutical company contributed 21.5 million free doses of mectizanr--a drug that prevents river blindness for a year--in the past year. Another pharmaceutical company donated albendazole for the global elimination of lymphatic filariasis. National pledges to a World Bank trust fund cover the costs of distributing donated medicines to the affected villages. The Common Agenda, a collaboration established between the US and Japan by the author, is an example of the potential of partnerships to create global political stability, correct environmental degradation, and promote the advantages of science and technology.

Recent Advances on the Use of Biochemical Extracts as Filaricidal Agents

PubMed Central

Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Al-Adhroey, Abdulelah H.; Suhaimi, Anwar; Sivanandam, S.

2013-01-01

Lymphatic filariasis is a parasitic infection that causes a devastating public health and socioeconomic burden with an estimated infection of over 120 million individuals worldwide. The infection is caused by three closely related nematode parasites, namely, Wuchereria bancrofti, Brugia malayi, and B. timori, which are transmitted to human through mosquitoes of Anopheles, Culex, and Aedes genera. The species have many ecological variants and are diversified in terms of their genetic fingerprint. The rapid spread of the disease and the genetic diversification cause the lymphatic filarial parasites to respond differently to diagnostic and therapeutic interventions. This in turn prompts the current challenge encountered in its management. Furthermore, most of the chemical medications used are characterized by adverse side effects. These complications urgently warrant intense prospecting on bio-chemicals that have potent efficacy against either the filarial worms or thier vector. In lieu of this, we presented a review on recent literature that reported the efficacy of filaricidal biochemicals and those employed as vector control agents. In addition, methods used for biochemical extraction, screening procedures, and structure of the bioactive compounds were also presented. PMID:24298292

Seroconversion to filarial antigens in Australian defence force personnel in Timor-Leste.

PubMed

Frances, Stephen P; Baade, Lisa M; Kubofcik, Joseph; Nutman, Thomas B; Melrose, Wayne D; McCarthy, James S; Nissen, Michael D

2008-04-01

To investigate whether Australian soldiers were exposed to filarial parasites that cause lymphatic filariasis during a 6-month deployment to Timor-Leste, antifilarial antibody levels were measured in 907 soldiers using an enzyme linked immunosorbent assay (ELISA). Initial testing using Dirofilaria immitis antigen demonstrated that 49 of 907 (5.4%) soldiers developed antifilarial antibodies of the IgG1 subclass after deployment, whereas 1 of 944 (0.1%) seroconverted to the IgG4 subclass. When a sub sample of 88 D. immitis-reactive sera was subject to testing with an antifilarial antibody test using Brugia malayi antigen, 46 had elevated IgG antibodies, whereas 5 had elevated antibodies of the IgG4 subclass. A total of 24 soldiers seroconverted to B. malayi, as measured by parasite-specific IgG, whereas 1 seroconverted to IgG4. The relatively low number of seroconversions indicates a low but measurable risk of exposure to human filarial parasites among Australian soldiers deployed to Timor-Leste. However, to reduce the risk of exposure to these parasites, soldiers deploying to endemic areas should practice strict adherence to personal protective measures against mosquito bites.

Impacts of neglected tropical disease on incidence and progression of HIV/AIDS, tuberculosis, and malaria: scientific links.

PubMed

Simon, G G

2016-01-01

The neglected tropical diseases (NTDs) are the most common infections of humans in Sub-Saharan Africa. Virtually all of the population living below the World Bank poverty figure is affected by one or more NTDs. New evidence indicates a high degree of geographic overlap between the highest-prevalence NTDs (soil-transmitted helminths, schistosomiasis, onchocerciasis, lymphatic filariasis, and trachoma) and malaria and HIV, exhibiting a high degree of co-infection. Recent research suggests that NTDs can affect HIV and AIDS, tuberculosis (TB), and malaria disease progression. A combination of immunological, epidemiological, and clinical factors can contribute to these interactions and add to a worsening prognosis for people affected by HIV/AIDS, TB, and malaria. Together these results point to the impacts of the highest-prevalence NTDs on the health outcomes of malaria, HIV/AIDS, and TB and present new opportunities to design innovative public health interventions and strategies for these 'big three' diseases. This analysis describes the current findings of research and what research is still needed to strengthen the knowledge base of the impacts NTDs have on the big three. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

Land use change and human health

NASA Astrophysics Data System (ADS)

Patz, Jonathan A.; Norris, Douglas E.

Disease emergence events have been documented following several types of land use change. This chapter reviews several health-relevant land use changes recognized today, including: 1) urbanization and urban sprawl; 2) water projects and agricultural development; 3) road construction and deforestation in the tropics; and 4) regeneration of temperate forests. Because habitat or climatic change substantially affects intermediate invertebrate hosts involved in many prevalent diseases, this chapter provides a basic description of vector-borne disease biology as a foundation for analyzing the effects of land use change. Urban sprawl poses health challenges stemming from heat waves exacerbated by the "urban heat island" effect, as well as from water contamination due to expanses of impervious road and concrete surfaces. Dams, irrigation and agricultural development have long been associated with diseases such as schistosomiasis and filariasis. Better management methods are required to address the trade-offs between expanded food production and altered habitats promoting deadly diseases. Deforestation can increase the nature and number of breeding sites for vector-borne diseases, such as malaria and onchocerciasis. Human host and disease vector interaction further increases risk, as can a change in arthropod-vector species composition.

The ecology of Anopheles mosquitoes under climate change: case studies from the effects of deforestation in East African highlands.

PubMed

Afrane, Yaw A; Githeko, Andrew K; Yan, Guiyun

2012-02-01

Climate change is expected to lead to latitudinal and altitudinal temperature increases. High-elevation regions such as the highlands of Africa and those that have temperate climate are most likely to be affected. The highlands of Africa generally exhibit low ambient temperatures. This restricts the distribution of Anopheles mosquitoes, the vectors of malaria, filariasis, and O'nyong'nyong fever. The development and survival of larval and adult mosquitoes are temperature dependent, as are mosquito biting frequency and pathogen development rate. Given that various Anopheles species are adapted to different climatic conditions, changes in climate could lead to changes in species composition in an area that may change the dynamics of mosquito-borne disease transmission. It is important to consider the effect of climate change on rainfall, which is critical to the formation and persistence of mosquito breeding sites. In addition, environmental changes such as deforestation could increase local temperatures in the highlands; this could enhance the vectorial capacity of the Anopheles. These experimental data will be invaluable in facilitating the understanding of the impact of climate change on Anopheles. © 2012 New York Academy of Sciences.

Behavioural aspects of the control of parasitic diseases*

PubMed Central

Dunn, Frederick L.

1979-01-01

Human behaviour has been largely neglected in research on the parasitic diseases, in part because of the long-standing separation of the behavioural disciplines from the physical and biomedical sciences. Some of the reasons for the persistence of this ”intellectual discontinuity” are discussed. The paper is principally concerned with the prospects for greater use of the methods and orientations of the behavioural sciences in parasitic disease research and control programmes. Behavioural research tends to fall into two categories employing, on the one hand, survey research and epidemiological methods and, on the other, participant observation and interviewing in depth. These approaches are shown to be complementary—equally useful and necessary. Various categories of health-related behaviour and kinds of research objective are reviewed in the following sections. Special attention is given to psychosocial cost—benefit studies, to analyses of control sectors, and to the formulation of a control philosophy. Finally, some specific behavioural research needs are discussed for some of the parasitic diseases of priority in the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases—schistosomiasis, filariasis, American and African trypanosomiases, and malaria. PMID:316733

Epidemiology of travel-associated infections in Oman 1999-2013: A retrospective analysis.

PubMed

Al-Abri, Seif S; Abdel-Hady, Doaa M; Al Mahrooqi, Salem S; Al-Kindi, Hanan S; Al-Jardani, Amina K; Al-Abaidani, Idris S

2015-01-01

The number of travelers in Oman has increased significantly in the last 2 decades with an increase in the expatriate population workforce leading to the emergence of infections related to travel. This paper aims to highlight the burden of travel-related infections in Oman. Our study is a descriptive record-based review and analysis of travel-associated diseases over a 14 year time period from 1999 to 2013. The data was sourced from the communicable disease surveillance system, and central public health laboratory results. From 1999 to 2013 there were a combined total of 7022 cases of cholera, chikungunya, dengue, filariasis, leptospirosis, meningococcal infection, poliomyelitis, measles, schistosomiasis, viral hepatitis (A), typhoid and para-typhoid reported to and subsequently investigated by the Department of Communicable Diseases. Among these cases, 558 (7.9%) were attributed to travel. Fifty percent of these patients were admitted to hospitals. Travel-associated infections account for about 8% of notifiable infections in Oman and have low mortality rate. However, some travel-associated infections are considered as a threat to polio eradication and measles elimination programs. Furthermore, some can cause outbreaks that can overwhelm the healthcare system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Green Nanoparticles for Mosquito Control

PubMed Central

Soni, Namita; Prakash, Soam

2014-01-01

Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicum or C. verum J. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM). The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs). The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito. PMID:25243210

Large-Scale Preventive Chemotherapy for the Control of Helminth Infection in Western Pacific Countries: Six Years Later

PubMed Central

Montresor, Antonio; Cong, Dai Tran; Sinuon, Mouth; Tsuyuoka, Reiko; Chanthavisouk, Chitsavang; Strandgaard, Hanne; Velayudhan, Raman; Capuano, Corinne M.; Le Anh, Tuan; Tee Dató, Ah S.

2008-01-01

In 2001, Urbani and Palmer published a review of the epidemiological situation of helminthiases in the countries of the Western Pacific Region of the World Health Organization indicating the control needs in the region. Six years after this inspiring article, large-scale preventive chemotherapy for the control of helminthiasis has scaled up dramatically in the region. This paper analyzes the most recent published and unpublished country information on large-scale preventive chemotherapy and summarizes the progress made since 2000. Almost 39 million treatments were provided in 2006 in the region for the control of helminthiasis: nearly 14 million for the control of lymphatic filariasis, more than 22 million for the control of soil-transmitted helminthiasis, and over 2 million for the control of schistosomiasis. In general, control of these helminthiases is progressing well in the Mekong countries and Pacific Islands. In China, despite harboring the majority of the helminth infections of the region, the control activities have not reached the level of coverage of countries with much more limited financial resources. The control of food-borne trematodes is still limited, but pilot activities have been initiated in China, Lao People's Democratic Republic, and Vietnam. PMID:18846234

Cell Type-Specific Immunomodulation Induced by Helminthes: Effect on Metainflammation, Insulin Resistance and Type-2 Diabetes.

PubMed

Aravindhan, Vivekanandhan; Anand, Gowrishankar

2017-12-01

Recent epidemiological studies have documented an inverse relationship between the decreasing prevalence of helminth infections and the increasing prevalence of metabolic diseases ("metabolic hygiene hypothesis"). Chronic inflammation leading to insulin resistance (IR) has now been identified as a major etiological factor for a variety of metabolic diseases other than obesity and Type-2 diabetes (metainflammation). One way by which helminth infections such as filariasis can modulate IR is by inducing a chronic, nonspecific, low-grade, immune suppression mediated by modified T-helper 2 (Th2) response (induction of both Th2 and regulatory T cells) which can in turn suppress the proinflammatory responses and promote insulin sensitivity (IS). This article provides evidence on how the cross talk between the innate and adaptive arms of the immune responses can modulate IR/sensitivity. The cross talk between innate (macrophages, dendritic cells, natural killer cells, natural killer T cells, myeloid derived suppressor cells, innate lymphoid cells, basophils, eosinophils, and neutrophils) and adaptive (helper T [CD4 + ] cells, cytotoxic T [CD8 + ] cells and B cells) immune cells forms two opposing circuits, one associated with IR and the other associated with IS under the conditions of metabolic syndrome and helminth-mediated immunomodulation, respectively.

Climate Change Contribution to the Emergence or Re-Emergence of Parasitic Diseases.

PubMed

Short, Erica E; Caminade, Cyril; Thomas, Bolaji N

2017-01-01

The connection between our environment and parasitic diseases may not always be straightforward, but it exists nonetheless. This article highlights how climate as a component of our environment, or more specifically climate change, has the capability to drive parasitic disease incidence and prevalence worldwide. There are both direct and indirect implications of climate change on the scope and distribution of parasitic organisms and their associated vectors and host species. We aim to encompass a large body of literature to demonstrate how a changing climate will perpetuate, or perhaps exacerbate, public health issues and economic stagnation due to parasitic diseases. The diseases examined include those caused by ingested protozoa and soil helminths, malaria, lymphatic filariasis, Chagas disease, human African trypanosomiasis, leishmaniasis, babesiosis, schistosomiasis, and echinococcus, as well as parasites affecting livestock. It is our goal to impress on the scientific community the magnitude a changing climate can have on public health in relation to parasitic disease burden. Once impending climate changes are now upon us, and as we see these events unfold, it is critical to create management plans that will protect the health and quality of life of the people living in the communities that will be significantly affected.

The Mosquitoes of Polynesia with a Pictorial Key to Some Species Associated with Filariasis and/or Dengue Fever

DTIC Science & Technology

1977-01-01

anterior surface c e e . . . . . . . . . . . . . . . . . roseni Belkin Urano taenia Propleuron with scales; vein R2 at most 0.6 length of vein Ml...annuZirostris Skuse The larva of samoaensis (Theobald) is unknown. Mosquito Systematics Vol. 9(3) 1977 Urano taenia Seta 9-M, T single . . o e

The rationale and cost-effectiveness of a confirmatory mapping tool for lymphatic filariasis: Examples from Ethiopia and Tanzania

PubMed Central

Pelletreau, Sonia; Barbre, Kira A.; Deming, Michael S.; Rebollo, Maria P.

2017-01-01

Endemicity mapping is required to determining whether a district requires mass drug administration (MDA). Current guidelines for mapping LF require that two sites be selected per district and within each site a convenience sample of 100 adults be tested for antigenemia or microfilaremia. One or more confirmed positive tests in either site is interpreted as an indicator of potential transmission, prompting MDA at the district-level. While this mapping strategy has worked well in high-prevalence settings, imperfect diagnostics and the transmission potential of a single positive adult have raised concerns about the strategy’s use in low-prevalence settings. In response to these limitations, a statistically rigorous confirmatory mapping strategy was designed as a complement to the current strategy when LF endemicity is uncertain. Under the new strategy, schools are selected by either systematic or cluster sampling, depending on population size, and within each selected school, children 9–14 years are sampled systematically. All selected children are tested and the number of positive results is compared against a critical value to determine, with known probabilities of error, whether the average prevalence of LF infection is likely below a threshold of 2%. This confirmatory mapping strategy was applied to 45 districts in Ethiopia and 10 in Tanzania, where initial mapping results were considered uncertain. In 42 Ethiopian districts, and all 10 of the Tanzanian districts, the number of antigenemic children was below the critical cutoff, suggesting that these districts do not require MDA. Only three Ethiopian districts exceeded the critical cutoff of positive results. Whereas the current World Health Organization guidelines would have recommended MDA in all 55 districts, the present results suggest that only three of these districts requires MDA. By avoiding unnecessary MDA in 52 districts, the confirmatory mapping strategy is estimated to have saved a total of $9,293,219. PMID:28976981

The rationale and cost-effectiveness of a confirmatory mapping tool for lymphatic filariasis: Examples from Ethiopia and Tanzania.

PubMed

Gass, Katherine M; Sime, Heven; Mwingira, Upendo J; Nshala, Andreas; Chikawe, Maria; Pelletreau, Sonia; Barbre, Kira A; Deming, Michael S; Rebollo, Maria P

2017-10-01

Endemicity mapping is required to determining whether a district requires mass drug administration (MDA). Current guidelines for mapping LF require that two sites be selected per district and within each site a convenience sample of 100 adults be tested for antigenemia or microfilaremia. One or more confirmed positive tests in either site is interpreted as an indicator of potential transmission, prompting MDA at the district-level. While this mapping strategy has worked well in high-prevalence settings, imperfect diagnostics and the transmission potential of a single positive adult have raised concerns about the strategy's use in low-prevalence settings. In response to these limitations, a statistically rigorous confirmatory mapping strategy was designed as a complement to the current strategy when LF endemicity is uncertain. Under the new strategy, schools are selected by either systematic or cluster sampling, depending on population size, and within each selected school, children 9-14 years are sampled systematically. All selected children are tested and the number of positive results is compared against a critical value to determine, with known probabilities of error, whether the average prevalence of LF infection is likely below a threshold of 2%. This confirmatory mapping strategy was applied to 45 districts in Ethiopia and 10 in Tanzania, where initial mapping results were considered uncertain. In 42 Ethiopian districts, and all 10 of the Tanzanian districts, the number of antigenemic children was below the critical cutoff, suggesting that these districts do not require MDA. Only three Ethiopian districts exceeded the critical cutoff of positive results. Whereas the current World Health Organization guidelines would have recommended MDA in all 55 districts, the present results suggest that only three of these districts requires MDA. By avoiding unnecessary MDA in 52 districts, the confirmatory mapping strategy is estimated to have saved a total of $9,293,219.

Accuracy of Coverage Survey Recall following an Integrated Mass Drug Administration for Lymphatic Filariasis, Schistosomiasis, and Soil-Transmitted Helminthiasis.

PubMed

Budge, Philip J; Sognikin, Edmond; Akosa, Amanda; Mathieu, Els M; Deming, Michael

2016-01-01

Achieving target coverage levels for mass drug administration (MDA) is essential to elimination and control efforts for several neglected tropical diseases (NTD). To ensure program goals are met, coverage reported by drug distributors may be validated through household coverage surveys that rely on respondent recall. This is the first study to assess accuracy in such surveys. Recall accuracy was tested in a series of coverage surveys conducted at 1, 6, and 12 months after an integrated MDA in Togo during which three drugs (albendazole, ivermectin, and praziquantel) were distributed. Drug distribution was observed during the MDA to ensure accurate recording of persons treated during the MDA. Information was obtained for 506, 1131, and 947 persons surveyed at 1, 6, and 12 months, respectively. Coverage (defined as the percentage of persons taking at least one of the MDA medications) within these groups was respectively 88.3%, 87.4%, and 80.0%, according to the treatment registers; it was 87.9%, 91.4% and 89.4%, according to survey responses. Concordance between respondents and registers on swallowing at least one pill was >95% at 1 month and >86% at 12 months; the lower concordance at 12 months was more likely due to difficulty matching survey respondents with the year-old treatment register rather than inaccurate responses. Respondents generally distinguished between pills similar in appearance; concordance for recall of which pills were taken was over 80% in each survey. In this population, coverage surveys provided remarkably consistent coverage estimates for up to one year following an integrated MDA. It is not clear if similar consistency will be seen in other settings, however, these data suggest that in some settings coverage surveys might be conducted as much as one year following an MDA without compromising results. This might enable integration of post-MDA coverage measurement into large, multipurpose, periodic surveys, thereby conserving resources.

Operational feasibility of lot quality assurance sampling (LQAS) as a tool in routine process monitoring of filariasis control programmes.

PubMed

Vanamail, P; Subramanian, S; Srividya, A; Ravi, R; Krishnamoorthy, K; Das, P K

2006-08-01

Lot quality assurance sampling (LQAS) with two-stage sampling plan was applied for rapid monitoring of coverage after every round of mass drug administration (MDA). A Primary Health Centre (PHC) consisting of 29 villages in Thiruvannamalai district, Tamil Nadu was selected as the study area. Two threshold levels of coverage were used: threshold A (maximum: 60%; minimum: 40%) and threshold B (maximum: 80%; minimum: 60%). Based on these thresholds, one sampling plan each for A and B was derived with the necessary sample size and the number of allowable defectives (i.e. defectives mean those who have not received the drug). Using data generated through simple random sampling (SRSI) of 1,750 individuals in the study area, LQAS was validated with the above two sampling plans for its diagnostic and field applicability. Simultaneously, a household survey (SRSH) was conducted for validation and cost-effectiveness analysis. Based on SRSH survey, the estimated coverage was 93.5% (CI: 91.7-95.3%). LQAS with threshold A revealed that by sampling a maximum of 14 individuals and by allowing four defectives, the coverage was >or=60% in >90% of villages at the first stage. Similarly, with threshold B by sampling a maximum of nine individuals and by allowing four defectives, the coverage was >or=80% in >90% of villages at the first stage. These analyses suggest that the sampling plan (14,4,52,25) of threshold A may be adopted in MDA to assess if a minimum coverage of 60% has been achieved. However, to achieve the goal of elimination, the sampling plan (9, 4, 42, 29) of threshold B can identify villages in which the coverage is <80% so that remedial measures can be taken. Cost-effectiveness analysis showed that both options of LQAS are more cost-effective than SRSH to detect a village with a given level of coverage. The cost per village was US dollars 76.18 under SRSH. The cost of LQAS was US dollars 65.81 and 55.63 per village for thresholds A and B respectively. The total financial cost of classifying a village correctly with the given threshold level of LQAS could be reduced by 14% and 26% of the cost of conventional SRSH method.

Accuracy of Coverage Survey Recall following an Integrated Mass Drug Administration for Lymphatic Filariasis, Schistosomiasis, and Soil-Transmitted Helminthiasis

PubMed Central

Budge, Philip J.; Sognikin, Edmond; Akosa, Amanda; Mathieu, Els M.; Deming, Michael

2016-01-01

Background Achieving target coverage levels for mass drug administration (MDA) is essential to elimination and control efforts for several neglected tropical diseases (NTD). To ensure program goals are met, coverage reported by drug distributors may be validated through household coverage surveys that rely on respondent recall. This is the first study to assess accuracy in such surveys. Methodology/Principal Findings Recall accuracy was tested in a series of coverage surveys conducted at 1, 6, and 12 months after an integrated MDA in Togo during which three drugs (albendazole, ivermectin, and praziquantel) were distributed. Drug distribution was observed during the MDA to ensure accurate recording of persons treated during the MDA. Information was obtained for 506, 1131, and 947 persons surveyed at 1, 6, and 12 months, respectively. Coverage (defined as the percentage of persons taking at least one of the MDA medications) within these groups was respectively 88.3%, 87.4%, and 80.0%, according to the treatment registers; it was 87.9%, 91.4% and 89.4%, according to survey responses. Concordance between respondents and registers on swallowing at least one pill was >95% at 1 month and >86% at 12 months; the lower concordance at 12 months was more likely due to difficulty matching survey respondents with the year-old treatment register rather than inaccurate responses. Respondents generally distinguished between pills similar in appearance; concordance for recall of which pills were taken was over 80% in each survey. Significance In this population, coverage surveys provided remarkably consistent coverage estimates for up to one year following an integrated MDA. It is not clear if similar consistency will be seen in other settings, however, these data suggest that in some settings coverage surveys might be conducted as much as one year following an MDA without compromising results. This might enable integration of post-MDA coverage measurement into large, multipurpose, periodic surveys, thereby conserving resources. PMID:26766287

The prevalences of Wuchereria bancrofti antigenaemia in communities given six rounds of treatment with diethylcarbamazine, ivermectin or placebo tablets.

PubMed

Ramaiah, K D; Vanamail, P; Pani, S P; Das, P K

2003-10-01

The ICT filariasis card test was used to determine the prevalences of Wuchereria bancrofti antigenaemia among villagers in India. Prior to the tests, those living in the 15 study villages had been treated six times, in six rounds of mass treatment (with 54%-75% coverage) spread over 6 years, with single doses of diethylcarbamazine (five villages), ivermectin (five villages) or placebo (five villages). The corresponding overall prevalences (and ranges) of filarial antigenaemia were 20.2% (13.7%-28.6%), 22.6% (15.3%-34.3%) and 25.9% (22.6%-29.3%), respectively. The overall prevalence of antigenaemia in the villages where diethylcarbamazine (DEC) had been distributed (but not that in the 'ivermectin' villages) was significantly lower than that recorded in the 'placebo' villages (z =2.56; P <0.05). The prevalences of antigenaemia among the villagers aged 1-5 years (18.9%, 15.6% and 22.4% in the DEC, ivermectin and placebo villages, respectively) did not differ significantly with treatment (P >0.05). The results indicate that annual mass treatments based on DEC or ivermectin, with 54%-75% treatment coverage, may have only a limited effect on the prevalence of infection with adult W. bancrofti. The possible reasons for the antigenaemias observed are discussed.

Neglected tropical diseases in Brazil.

PubMed

Lindoso, José Angelo L; Lindoso, Ana Angélica B P

2009-01-01

Poverty is intrinsically related to the incidence of Neglected Tropical Diseases (NTDs). The main countries that have the lowest human development indices (HDI) and the highest burdens of NTDs are located in tropical and subtropical regions of the world. Among these countries is Brazil, which is ranked 70th in HDI. Nine out of the ten NTDs established by the World Health Organization (WHO) are present in Brazil. Leishmaniasis, tuberculosis, dengue fever and leprosy are present over almost the entire Brazilian territory. More than 90% of malaria cases occur in the Northern region of the country, and lymphatic filariasis and onchocerciasis occur in outbreaks in a particular region. The North and Northeast regions of Brazil have the lowest HDIs and the highest rates of NTDs. These diseases are considered neglected because there is not important investment in projects for the development of new drugs and vaccines and existing programs to control these diseases are not sufficient. Another problem related to NTDs is co-infection with HIV, which favors the occurrence of severe clinical manifestations and therapeutic failure. In this article, we describe the status of the main NTDs currently occurring in Brazil and relate them to the HDI and poverty.

Apoptotic impact on Brugia malayi by sulphonamido-quinoxaline: search for a novel therapeutic rationale.

PubMed

Bhoj, Priyanka S; Ingle, Rahul G; Goswami, Kalyan; Jena, Lingaraj; Wadher, Shailesh

2018-05-01

Human lymphatic filariasis although not fatal but poses serious socioeconomic burden due to associated disability. This is reflected by the huge magnitude of the estimated disability-adjusted life years of about 5.09 million. Therefore, following WHO mandate, our earlier studies on antifilarial drug development revealed the significance of apoptosis. Apoptotic impact has been implicated in anticancer rationale of several drugs. In this study, we explored the antifilarial potential of sulphonamido-quinoxaline compounds, shown to be specific inhibitor for c-Met kinase in human cancer cells. Out of studied compounds, Q4, showing favorable drug-likeness and medicinal chemistry properties on bioinformatics platform along with subsequently recorded lowest IC 100 value, was considered as a suitable antifilarial candidate. Significant apoptosis due to mitochondrial involvement was recorded in drug-treated parasite unlike untreated control. In spite of homology between human c-Met kinase and Brugia malayi counterpart, comparative docking result of this compound showed more favorable binding parameters with the parasitic target. The wide gap between IC 100 and LD 50 values further confirmed the therapeutic safety. We propose sulphonamido-quinoxaline derivative as a lead candidate for antifilarial drug development. Further study is warranted to authenticate parasitic c-Met kinase as a novel therapeutic target reminiscent of anticancer rationale implicating inhibition of proliferation.

Synthesis, spectral characterization and larvicidal activity of acridin-1(2H)-one analogues

NASA Astrophysics Data System (ADS)

Subashini, R.; Bharathi, A.; Roopan, Selvaraj Mohana; Rajakumar, G.; Abdul Rahuman, A.; Gullanki, Pavan Kumar

Acridin-1(2H)-one analogue of 7-chloro-3,4-dihydro-9-phenyl-2-[(pyridine-2yl) methylene] acridin-1(2H)-one, 5 was prepared by using 7-chloro-3,4-dihydro-9-phenylacridin-1(2H)-one, 3 and picolinaldehyde, 4 in the presence of KOH at room temperature. These compounds were characterized by analytical and spectral analyses. The purpose of the present study was to assess the efficacy of larvicidal and repellent activity of synthesized 7-chloro-3,4-dihydro-9-phenyl-acridin-1(2H)-one analogues such as compounds 3 and 5 against the early fourth instar larvae of filariasis vector, Culex quinquefasciatus and Japanese encephalitis vector, Culex gelidus (Diptera: Culicidae). The compound exhibited high larvicidal effects at 50 mg/L against both the mosquitoes with LC50 values of 25.02 mg/L (r2 = 0.998) and 26.40 mg/L (r2 = 0.988) against C. quinquefasciatus and C. gelidus, respectively. The 7-chloro-3,4-dihydro-9-phenyl-acridin-1(2H)-one analogues that are reported for the first time to our best of knowledge can be better explored for the control of mosquito population. This is an ideal ecofriendly approach for the control of Japanese encephalitis vectors, C. quinquefasciatus and C. gelidus.

Iron and iron oxide nanoparticles are highly toxic to Culex quinquefasciatus with little non-target effects on larvivorous fishes.

PubMed

Murugan, Kadarkarai; Dinesh, Devakumar; Nataraj, Devaraj; Subramaniam, Jayapal; Amuthavalli, Pandiyan; Madhavan, Jagannathan; Rajasekar, Aruliah; Rajan, Mariappan; Thiruppathi, Kulandhaivel Palani; Kumar, Suresh; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni

2018-04-01

The control of filariasis vectors has been enhanced in several areas, but there are main challenges, including increasing resistance to insecticides and lack of cheap and eco-friendly products. The toxicity of iron (Fe 0 ) and iron oxide (Fe 2 O 3 ) nanoparticles has been scarcely investigated yet. We studied the larvicidal and pupicidal activity of Fe 0 and Fe 2 O 3 nanoparticles against Culex quinquefasciatus. Fe 0 and Fe 2 O 3 nanoparticles produced by green (using a Ficus natalensis aqueous extract) and chemical nanosynthesis, respectively, were analyzed by UV-Vis spectrophotometry, FT-IR spectroscopy, XRD analysis, SEM, and EDX assays. In larvicidal and pupicidal experiments on Cx. quinquefasciatus, LC 50 of Fe 0 nanoparticles ranged from 20.9 (I instar larvae) to 43.7 ppm (pupae) and from 4.5 (I) to 22.1 ppm (pupae) for Fe 2 O 3 nanoparticles synthesized chemically. Furthermore, the predation efficiency of the guppy fish, Poecilia reticulata, after a single treatment with sub-lethal doses of Fe 0 and Fe 2 O 3 nanoparticles was magnified. Overall, this work provides new insights about the toxicity of Fe 0 and Fe 2 O 3 nanoparticles against mosquito vectors; we suggested that green and chemical fabricated nano-iron may be considered to develop novel and effective pesticides.

Kernel-density estimation and approximate Bayesian computation for flexible epidemiological model fitting in Python.

PubMed

Irvine, Michael A; Hollingsworth, T Déirdre

2018-05-26

Fitting complex models to epidemiological data is a challenging problem: methodologies can be inaccessible to all but specialists, there may be challenges in adequately describing uncertainty in model fitting, the complex models may take a long time to run, and it can be difficult to fully capture the heterogeneity in the data. We develop an adaptive approximate Bayesian computation scheme to fit a variety of epidemiologically relevant data with minimal hyper-parameter tuning by using an adaptive tolerance scheme. We implement a novel kernel density estimation scheme to capture both dispersed and multi-dimensional data, and directly compare this technique to standard Bayesian approaches. We then apply the procedure to a complex individual-based simulation of lymphatic filariasis, a human parasitic disease. The procedure and examples are released alongside this article as an open access library, with examples to aid researchers to rapidly fit models to data. This demonstrates that an adaptive ABC scheme with a general summary and distance metric is capable of performing model fitting for a variety of epidemiological data. It also does not require significant theoretical background to use and can be made accessible to the diverse epidemiological research community. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

[Current situation and developmental trend of anthelmintics by bibliometrics].

PubMed

Zheng, Qi; Chen, Ying; Tian, Li-Guang; Zhou, Xiao-Nong

2009-08-01

To understand the current situation and developmental trend of anthelmintics in English journals through a bibliometric analysis. The literature was searched in Pubmed Database (1997-2007) using the following key words: "drug therapy", "anthelmintics", "humans", "pharmacology", and "parasitology". Access Database was constructed by relative literature through proper data admission method. The relative articles in the database were sorted by different categories, such as "research categories", "publishing year" and "research drug". Data were analyzed by using SPSS software. The annual number of anthelmintics articles increased steadily from year 1997 to 2007. The average number of annual increase was about 6. The major research category was applied research. The major diseases were schistosomiasis, filariasis, ascariasis, echinococcosis and hookworm disease. The number of articles on schistosomiasis was higher than that of other four diseases (P<0.05). The major drugs involved were albendazole, praziquantel, mebendazole, ivermectin and diethylcarbamazine. Articles on the anthelmintics were published mostly in medical journals. From the total database, articles published at the top five journals occupied 5.52%, 4.39%, 3.76%, 3.26%, and 3.26%, respectively. Increasingly importance has been attached to anthelmintics in the last decade. Meanwhile, the researchers focused on a few anthelmintics, and it is inevitable to develop new drugs.

Current and potential impacts of mosquitoes and the pathogens they vector in the Pacific region

USGS Publications Warehouse

LaPointe, Dennis

2007-01-01

Mosquitoes and the pathogens they transmit are ubiquitous throughout most of the temperate and tropical regions of the world. The natural and pre-European distribution and diversity of mosquitoes and mosquito-borne diseases throughout much of the Pacific region, however, depicts a depauperate and relatively benign fauna reinforcing the dream of “paradise regained”. In the central and South Pacific few mosquito species were able to colonize the remotest islands and atolls. Native mosquitoes are limited to a few far-ranging species and island endemics are typically restricted to the genera of Aedes and Culex. Only lymphatic filariasis appears to have been present as an endemic mosquito-borne disease before European contact. In nearby Australia, however, some 242 species of mosquitoes are known to occur and more than 70 arboviruses have been identified (Mackenzie 1999). In this regard Australia is more similar to the rest of the tropic and subtropical world than the smaller islands of Oceania. In our ever-shrinking world of global commerce, military activity and travel, the nature of mosquito-borne disease in the Pacific was bound to change. This paper is a brief summary of introduced mosquitoes in the Pacific and their potential impacts on human and wildlife health.

[The road to elimination: an overview of neglected infectious diseases in Latin America and the Caribbean].

PubMed

Ault, Steven Kenyon; Catalá Pascual, Laura; Grados-Zavala, Maria Elena; Gonzálvez García, Guillermo; Castellanos, Luis Gerardo

2014-04-01

Neglected infectious diseases (NID) affect mainly isolated populations living in isolation and in poor socioeconomic conditions. These diseases, by their chronic and silent nature, often affect communities with a weak political voice. This translates into very little attention or political priority; which is reflected in minimal and insufficient preventive measures, monitoring and control. However, there is evidence this situation is changing favorably in some countries of the Americas. In recent years, several resolutions (official agreement of the member countries of the Pan American Health Organization / World Health Organization-PAHO / WHO), regional and global agreements on public health; with a greater commitment from the pharmaceutical industry, and other donors and international partners in combination with the development and use of integrated action plans have allowed countries to intensify public interventions to control these diseases and thus achieve target elimination of NID. Onchocerciasis, lymphatic filariasis, Chagas disease, leprosy and trachoma blindness, among others, have been eliminated in several countries and endemic areas, regardless of the level of development of the country or geographical area where they are located. The political decision reflected in adequate financial resources in the next decade will be crucial to achieving the goals of elimination of NID (regional and national).

IUD users may have higher risk of contracting PID, studies find; pill may have protective effect.

PubMed

1980-01-01

The incidence of pelvic inflammatory disease (PID), which can lead to serious reproductive impairment, infertility, or ectopic pregnancy, is increasing worldwide. About 500,000 women in their childbearing years contract PID for the first time each year in the U.S., and the incidence among young women appears to be increasing. Sexually transmitted diseases are responsible for many PID cases worldwide, while in developing countries postpartum and postabortion sepsis and endemic diseases such as filariasis and schistosomiasis may also be implicated. Some increase of PID is associated with legal abortion and IUD insertion, while pill use appears to protect women from PID. A worldwide review of medical literature indicates that the risk of PID is 3.5 times greater for IUD users than for nonusers, although several variables other than IUD use affect PID risk, such as age, race, socioeconomic status, and sexual activity. The risk for never pregnant IUD users in a Swedish study was 11.8 per 100 woman years, compared to 3.4 for ever-pregnant IUD users. There was no difference in relative risk for users of the pill or barrier methods, or for non-contraceptors. Another study reported a higher relative risk of PID related to duration of IUD use.

Diterpenes as lead molecules against neglected tropical diseases.

PubMed

Barros de Alencar, Marcus Vinícius Oliveira; de Castro E Sousa, João Marcelo; Rolim, Hercília Maria Lins; de Medeiros, Maria das Graças Freire; Cerqueira, Gilberto Santos; de Castro Almeida, Fernanda Regina; Citó, Antônia Maria das Graças Lopes; Ferreira, Paulo Michel Pinheiro; Lopes, José Arimatéia Dantas; de Carvalho Melo-Cavalcante, Ana Amélia; Islam, Md Torequl

2017-02-01

Nowadays, neglected tropical diseases (NTDs) are reported to be present everywhere. Poor and developing areas in the world have received great attention to NTDs. Drug resistance, safety profile, and various challenges stimulate the search for alternative medications. Plant-based drugs are viewed with great interest, as they are believed to be devoid of side effects. Diterpenes, a family of essential oils, have showed attractive biological effects. A systematic review of the literature was carried out to summarize available evidences of diterpenes against NTDs. For this, databases were searched using specific search terms. Among the 2338 collected reports, a total of 181 articles were included in this review. Of them, 148 dealt with investigations using single organisms, and 33 used multiple organisms. No mechanisms of action were reported in the case of 164 reports. A total of 93.92% were related to nonclinical studies, and 4.42% and 1.66% dealt with preclinical and clinical studies, respectively. The review displays that many diterpenes are effective upon Chagas disease, chikungunya, echinococcosis, dengue, leishmaniasis, leprosy, lymphatic filariasis, malaria, schistosomiasis, and tuberculosis. Indeed, diterpenes are amazing drug candidates against NTDs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Natural Mosquito-Pathogen Hybrid IgG4 Antibodies in Vector-Borne Diseases: A Hypothesis.

PubMed

Londono-Renteria, Berlin; Cardenas, Jenny C; Troupin, Andrea; Colpitts, Tonya M

2016-01-01

Chronic exposure to antigens may favor the production of IgG4 antibodies over other antibody types. Recent studies have shown that up to a 30% of normal human IgG4 is bi-specific and is able to recognize two antigens of different nature. A requirement for this specificity is the presence of both eliciting antigens in the same time and at the same place where the immune response is induced. During transmission of most vector-borne diseases, the pathogen is delivered to the vertebrate host along with the arthropod saliva during blood feeding and previous studies have shown the existence of IgG4 antibodies against mosquito salivary allergens. However, there is very little ongoing research or information available regarding IgG4 bi-specificity with regard to infectious disease, particularly during immune responses to vector-borne diseases, such as malaria, filariasis, or dengue virus infection. Here, we provide background information and present our hypothesis that IgG4 may not only be a useful tool to measure exposure to infected mosquito bites, but that these bi-specific antibodies may also play an important role in modulation of the immune response against malaria and other vector-borne diseases in endemic settings.

Recent advances in tropical medicine.

PubMed

Solomon, Anthony W; Nayagam, Shevanthi; Pasvol, Geoffrey

2009-07-01

There have been significant advances in both the classical and neglected tropical diseases, with Guinea worm looking set to be the next disease after smallpox to be eradicated. Aided by a combination of enhanced understanding of the biology of the pathogens, intensification of immunisation activities or mass drug administration, together with the development of synergies with control programmes for co-endemic tropical diseases, polio, lymphatic filariasis, trachoma and onchocerciasis all appear to be in global decline, with good prospects for eventual successful elimination. While the global incidence of new cases of leprosy continues to decrease, the focus of leprosy control efforts has shifted following more widespread recognition that cure of infection does not necessarily prevent disability. Expansion in funding for HIV/AIDS and malaria provides some grounds for optimism about the control of these diseases. However, ongoing education and access remain essential to increasing the uptake of HIV testing and decreasing transmission. Meanwhile, the rise of drug-resistant tuberculosis and malaria is concerning, and the emergence of the highly pathogenic avian influenza A and re-emergence of viruses such as chikungunya and West Nile virus, without significant recent progress in vaccine development, pose additional ongoing challenges to tropical medicine physicians worldwide.

A survey of basic reproductive ratios in vector-borne disease transmission modeling

NASA Astrophysics Data System (ADS)

Soewono, E.; Aldila, D.

2015-03-01

Vector-borne diseases are commonly known in tropical and subtropical countries. These diseases have contributed to more than 10% of world infectious disease cases. Among the vectors responsible for transmitting the diseases are mosquitoes, ticks, fleas, flies, bugs and worms. Several of the diseases are known to contribute to the increasing threat to human health such as malaria, dengue, filariasis, chikungunya, west nile fever, yellow fever, encephalistis, and anthrax. It is necessary to understand the real process of infection, factors which contribute to the complication of the transmission in order to come up with a good and sound mathematical model. Although it is not easy to simulate the real transmission process of the infection, we could say that almost all models have been developed from the already long known Host-Vector model. It constitutes the main transmission processes i.e. birth, death, infection and recovery. From this simple model, the basic concepts of Disease Free and Endemic Equilibria and Basic Reproductive Ratio can be well explained and understood. Theoretical, modeling, control and treatment aspects of disease transmission problems have then been developed for various related diseases. General construction as well as specific forms of basic reproductive ratios for vector-borne diseases are discusses here.

Public-private partnerships in neglected tropical disease control: the role of nongovernmental organisations.

PubMed

Bush, S; Hopkins, A D

2011-09-01

Successful public-private partnerships for health control have usually included nongovernmental development organisations (NGDOs), and these have long been in the forefront of pinpointing particular social and health issues. The immensely successful control and elimination programmes for onchocerciasis are a case in point. NGDOs were the driving force in early advocacy for onchocerciasis control in West Africa, leading eventually to the remarkably effective and long lasting partnership of the Onchocerciasis Control Programme (OCP). With the donation of Mectizan(®), NGDOs were the driving force in developing onchocerciasis control in non-OCP countries, especially programmes for community based action. These were, further modified by the African Programme for Onchocerciasis Control (APOC) to become the successful Community Directed Interventions. NGDOs came together to coordinate activities in partnership with the World Health Organisation (WHO). Innovations by NGDOs led to integration of mass drug administration for Vitamin A deficiency and then for other parasitic diseases, leading to the current trend of preventive chemotherapy. The success of the NGDO Group for Onchocerciasis Control has led to the creation of similar groups for trachoma control and lymphatic filariasis elimination. These groups have now come together to form an NGDO Network for Neglected Tropical Disease control. Copyright © 2011 Elsevier B.V. All rights reserved.

A case of loiasis in Rome.

PubMed

Morrone, A; Franco, G; Toma, L; Tchangmena, O B; Marangi, M

2002-05-01

Owing to the increase of an immigrant population and of Italian citizens travelling for tourism or on business, it is nowadays possible to observe clinical pictures characteristic of tropical regions, often with indistinct symptoms. One of these is Loa loa infestation, or loiasis, a form of filariasis caused by Loa loa and transmitted by the Chrysops fly. We present the case of a male immigrant from Cameroon. Characteristic symptoms were intense xerosis, mostly of the third inferior part of the legs, intensely pruritic, with numerous lesions from scratching. No benefit was obtained by emollient topics, anti-acarus and systemic antihistamines. Serum samples and Giemsa, haematoxylin, haematoxylin + Giemsa concentration-on-membrane stains, have evidenced the presence of Loa loa microfilariae. A diagnosis for L. loa (loiasis) infestation was made. At the beginning of the migration phenomenon, particularly from Africa, Italian physicians, especially dermatologists, were eagerly looking for 'tropical' diseases; this approach can be defined as 'Salgari's syndrome' from the name of the Italian novelist who, though never travelling out of Italy, had perfectly described environments and habits typical of far away countries. Now, conversely, we have to avoid the opposite approach of considering real tropical diseases as related to social or psychological difficult conditions.

Epidemiology and Individual, Household and Geographical Risk Factors of Podoconiosis in Ethiopia: Results from the First Nationwide Mapping

PubMed Central

Deribe, Kebede; Brooker, Simon J.; Pullan, Rachel L.; Sime, Heven; Gebretsadik, Abeba; Assefa, Ashenafi; Kebede, Amha; Hailu, Asrat; Rebollo, Maria P.; Shafi, Oumer; Bockarie, Moses J.; Aseffa, Abraham; Reithinger, Richard; Cano, Jorge; Enquselassie, Fikre; Newport, Melanie J.; Davey, Gail

2015-01-01

Although podoconiosis is one of the major causes of tropical lymphoedema and is endemic in Ethiopia its epidemiology and risk factors are poorly understood. Individual-level data for 129,959 individuals from 1,315 communities in 659 woreda (districts) were collected for a nationwide integrated survey of lymphatic filariasis and podoconiosis. Blood samples were tested for circulating Wuchereria bancrofti antigen using immunochromatographic card tests. A clinical algorithm was used to reach a diagnosis of podoconiosis by excluding other potential causes of lymphoedema of the lower limb. Bayesian multilevel models were used to identify individual and environmental risk factors. Overall, 8,110 of 129,959 (6.2%, 95% confidence interval [CI] 6.1–6.4%) surveyed individuals were identified with lymphoedema of the lower limb, of whom 5,253 (4.0%, 95% CI 3.9–4.1%) were confirmed to be podoconiosis cases. In multivariable analysis, being female, older, unmarried, washing the feet less frequently than daily, and being semiskilled or unemployed were significantly associated with increased risk of podoconiosis. Attending formal education and living in a house with a covered floor were associated with decreased risk of podoconiosis. Podoconiosis exhibits marked geographical variation across Ethiopia, with variation in risk associated with variation in rainfall, enhanced vegetation index, and altitude. PMID:25404069

A systematic study on hemocyte identification and plasma prophenoloxidase from Culex pipiens quinquefasciatus at different developmental stages.

PubMed

Wang, Zhixiang; Lu, Anrui; Li, Xuquan; Shao, Qimiao; Beerntsen, Brenda T; Liu, Chaoliang; Ma, Yajun; Huang, Yamin; Zhu, Huaimin; Ling, Erjun

2011-01-01

Culexpipiens quinquefasciatus (C. quinquefasciatus) is an important vector that can transmit human diseases such as West Nile virus, lymphatic filariasis, Japanese encephalitis and St. Louis encephalitis. However, very limited research concerning the humoral and cellular immune defenses of C. quinquefasciatus has been done. Here we present the research on hemocyte identification and plasma including hemocyte prophenoloxidase from C. quinquefasciatus at all developmental stages in order to obtain a complete picture of C. quinquefasciatus innate immunity. We identified hemocytes into four types: prohemocytes, oenocytoids, plasmatocytes and granulocytes. Prophenoloxidase (PPO) is an essential enzyme to induce melanization after encapsulation. PPO-positive hemocytes and plasma PPO were observed at all developmental stages. As for specific hemocyte types, prophenoloxidase was found in the plasmatocytes at larval stage alone and in the smallest prohemocytes during almost all developmental stages. Moreover, the granulocytes were PPO-positive from blood-fed female mosquitoes and oenocytoids were observed PPO-positive in pupae and in adult females after blood-feeding. As for plasma, there were different patterns of PPO in C. quinquefasciatus at different developmental stages. These results are forming a basis for further studies on the function of C. quinquefasciatus hemocytes and prophenoloxidase as well as their involvement in fighting against mosquito-borne pathogens. Copyright © 2010 Elsevier Inc. All rights reserved.

Detection of Leishmania amazonensis and Leishmania braziliensis in Culicoides (Diptera, Ceratopogonidae) in an endemic area of cutaneous leishmaniasis in the Brazilian Amazonia.

PubMed

Rebêlo, José Manuel Macário; Rodrigues, Bruno Leite; Bandeira, Maria da Conceição Abreu; Moraes, Jorge Luiz Pinto; Fonteles, Raquel Silva; Pereira, Silma Regina Ferreira

2016-12-01

Biting midges in the genus Culicoides act as vectors of arboviruses throughout the world and as vectors of filariasis in Latin America, the Caribbean, and parts of Africa. Although Culicoides spp. are currently not considered to be vectors of Leishmania protozoa, the high abundance of biting midges in areas with active cutaneous leishmaniasis transmission points to the possibility of Culicoides infection by these pathogens. We used PCR to test captured Culicoides species for natural infection with Leishmania spp. We tested 450 Culicoides females, divided into 30 pools of 15 individuals each, as follows: nine pools of C. foxi (135 specimens), seven pools of C. filariferus (105), seven pools of C. insignis (105), five pools of C. ignacioi (75), and two pools of C. flavivenula (30). PCR confirmed the presence of Leishmania braziliensis DNA in C. ignacioi (0.14%), C. insignis (0.14%), and C. foxi (0.11); and Le. amazonensis DNA in C. filariferus (0.14%) and C. flavivenula (0.50%). We conclude that these Culicoides species can be naturally infected, but vector competence and transmission capability must be confirmed in future studies. Our results warrant further investigation into the role of these biting midge species in the leishmaniasis epidemiological cycle. © 2016 The Society for Vector Ecology.

Epidemiology of tree-hole breeding mosquitoes in the tropical rainforest of Imo State, south-east Nigeria.

PubMed

Anosike, Jude C; Nwoke, Bertram E B; Okere, Anthony N; Oku, Ene E; Asor, Joe E; Emmy-Egbe, Ifeyinwa O; Adimike, Desmond A

2007-01-01

The study of tree-hole breeding mosquitoes was carried out in the tropical rainforest of Imo State Nigeria (two rural areas and two forest reserves in some parts of Orlu Senatorial Zone) between May-October 2002. Using standard entomological procedures, two macrohabitats (natural tree-holes and bamboo traps) and two microhabitats (leaf axils of cocoyams/pineapples and leaf axils of plantain/banana) were sampled for various mosquito species. Mosquitoes were recovered from all the various biotypes sampled. Types of mosquitoes species encountered, their relative abundance, as well as genera varied significantly during the study (p<0.05). Four genera of mosquitoes: Aedes, Culex, Anopheles and Toxorhynchites were recovered while 16 species of mosquitoes encountered include: Aedes aegypti, Ae. africanus, Ae. simpsoni, Ae. albopictus, Ae. stokesi, Ae. taylori, Ae. apicoargenteus, Culex quinquefasciatus, Cx. nebulosus, Cx. trigripes, Cx. decens, Anopheles gambiae, An. funiestus, An. coustani and Toxorhynchites viridibasis. Most of the mosquitoes showed oviposition preferences for one or more habitats. The presence of Ae. africanus, Ae. simpsoni and Ae. aegypti indicate that the study areas were at risk of yellow fever epidemic. The presence of Anopheles and Culex species ensured endemicity of malaria and filariasis, while the recovery of Ae. albopictus in this region suggests a possible outbreak of dengue fever in future if not properly controlled.

Migratory phase of Litomosoides sigmodontis filarial infective larvae is associated with pathology and transient increase of S100A9 expressing neutrophils in the lung

PubMed Central

Pionnier, Nicolas; Vallarino-Lhermitte, Nathaly; Lefoulon, Emilie; Nieguitsila, Adélaïde; Specht, Sabine; Carlin, Leo M.; Martin, Coralie

2017-01-01

Filarial infections are tropical diseases caused by nematodes of the Onchocercidae family such as Mansonella perstans. The infective larvae (L3) are transmitted into the skin of vertebrate hosts by blood-feeding vectors. Many filarial species settle in the serous cavities including M. perstans in humans and L. sigmodontis, a well-established model of filariasis in mice. L. sigmodontis L3 migrate to the pleural cavity where they moult into L4 around day 9 and into male and female adult worms around day 30. Little is known of the early phase of the parasite life cycle, after the L3 is inoculated in the dermis by the vector and enters the afferent lymphatic vessels and before the moulting processes in the pleural cavity. Here we reveal a pulmonary phase associated with lung damage characterized by haemorrhages and granulomas suggesting L3 reach the lung via pulmonary capillaries and damage the endothelium and parenchyma by crossing them to enter the pleural cavity. This study also provides evidence for a transient inflammation in the lung characterized by a very early recruitment of neutrophils associated with high expression levels of S100A8 and S100A9 proteins. PMID:28486498

Community perceptions on the community-directed treatment and school-based approaches for the control of schistosomiasis and soil-transmitted helminthiasis among school-age children in Lushoto District, Tanzania.

PubMed

Massa, K; Magnussen, P; Sheshe, A; Ntakamulenga, R; Ndawi, B; Olsen, A

2009-01-01

The success of the Community-Directed Treatment (ComDT) approach in the control of onchocerciasis and filariasis has caught the attention of other disease control programmes. In this study the ComDT approach was implemented and compared with the school-based approach for control of schistosomiasis and soil-transmitted helminthiasis among school-age children in Lushoto District, Tanzania. This was a qualitative study, consisting of in-depth interviews with village leaders, community drug distributors (CDDs) and schoolteachers, as well as focus group discussions with separate groups of mothers and fathers to assess the perceptions and experiences of the villagers on the implementation of the two approaches. It was found that the villagers accepted the ComDT approach and took the responsibility of selecting the CDDs, organizing and implementing their own method of distributing drugs to the school-age children in their villages. The ComDT approach was well received and was successfully implemented in the villages. Although the villagers pointed out the limitation in reaching the non-enrolled children in the school-based approach, they also expressed satisfaction with this approach. This study suggests that the ComDT approach is well accepted and can be implemented effectively to ensure better coverage of especially non-enrolled school-age children.

Climate Change Contribution to the Emergence or Re-Emergence of Parasitic Diseases

PubMed Central

Short, Erica E; Caminade, Cyril; Thomas, Bolaji N

2017-01-01

The connection between our environment and parasitic diseases may not always be straightforward, but it exists nonetheless. This article highlights how climate as a component of our environment, or more specifically climate change, has the capability to drive parasitic disease incidence and prevalence worldwide. There are both direct and indirect implications of climate change on the scope and distribution of parasitic organisms and their associated vectors and host species. We aim to encompass a large body of literature to demonstrate how a changing climate will perpetuate, or perhaps exacerbate, public health issues and economic stagnation due to parasitic diseases. The diseases examined include those caused by ingested protozoa and soil helminths, malaria, lymphatic filariasis, Chagas disease, human African trypanosomiasis, leishmaniasis, babesiosis, schistosomiasis, and echinococcus, as well as parasites affecting livestock. It is our goal to impress on the scientific community the magnitude a changing climate can have on public health in relation to parasitic disease burden. Once impending climate changes are now upon us, and as we see these events unfold, it is critical to create management plans that will protect the health and quality of life of the people living in the communities that will be significantly affected. PMID:29317829

Novel synthesis of silver nanoparticles using Bauhinia variegata: a recent eco-friendly approach for mosquito control.

PubMed

Govindarajan, Marimuthu; Rajeswary, Mohan; Veerakumar, Kaliyan; Muthukumaran, Udaiyan; Hoti, S L; Mehlhorn, Heinz; Barnard, Donald R; Benelli, Giovanni

2016-02-01

Mosquito vectors are responsible for transmitting diseases such as malaria, dengue, chikungunya, Japanese encephalitis, dengue, and lymphatic filariasis. The use of synthetic insecticides to control mosquito vectors has caused physiological resistance and adverse environmental effects, in addition to high operational cost. Biosynthesis of silver nanoparticles has been proposed as an alternative to traditional control tools. In the present study, green synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract of Bauhinia variegata by reduction of Ag(+) ions from silver nitrate solution has been investigated. The bioreduced silver nanoparticles were characterized by UV–visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), and X-ray diffraction analysis (XRD). Leaf extract and synthesized AgNPs were evaluated against the larvae of Anopheles subpictus, Aedes albopictus, and Culex tritaeniorhynchus. Compared to aqueous extract, synthesized AgNPs showed higher toxicity against An. subpictus, Ae. albopictus, and Cx. tritaeniorhynchus with LC50 and LC90 values of 41.96, 46.16, and 51.92 μg/mL and 82.93, 89.42, and 97.12 μg/mL, respectively. Overall, this study proves that B. variegata is a potential bioresource for stable, reproducible nanoparticle synthesis and may be proposed as an efficient mosquito control agent.

Biolarvicidal compound gymnemagenol isolated from leaf extract of miracle fruit plant, Gymnema sylvestre (Retz) Schult against malaria and filariasis vectors.

PubMed

Khanna, Venkatesan Gopiesh; Kannabiran, Krishnan; Rajakumar, Govindasamy; Rahuman, Abdul Abdul; Santhoshkumar, Thirunavukkarasu

2011-11-01

Owing to the fact that the application of synthetic larvicide has envenomed the surroundings as well as non-target organisms, natural products of plant origin with insecticidal properties have been tried as an indigenous method for the control of a variety of insect pests and vectors in the recent past. Insecticides of plant origin have been extensively used on agricultural pests and, to a very limited extent, against insect vectors of public health importance, which deserve careful and thorough screening. The use of plant extracts for insect control has several appealing features as these are generally more biodegradable, less hazardous and a rich storehouse of chemicals of diverse biological activities. Moreover, herbal sources give a lead for discovering new insecticides. Therefore, biologically active plant materials have attracted considerable interest in mosquito control study in recent times. The crude leaf extracts of Gymnema sylvestre (Retz) Schult (Asclepiadaceae) and purified gymnemagenol compound were studied against the early fourth-instar larvae of Anopheles subpictus Grassi and Culex quinquefasciatus Say (Diptera: Culicidae). In the present study, bioassay-guided fractionation of petroleum ether leaf extract of G. sylvestre led to the separation and identification of gymnemagenol as a potential new antiparasitic compound. Phytochemical analysis of G. sylvestre leaves revealed the presence of active constituents such as carbohydrates, saponins, phytosterols, phenols, flavonoids and tannins. However, cardiac glycosides and phlobatannins are absent in the plant extracts. Quantitative analysis results suggested that saponin (5%) was present in a high concentration followed by tannins (1.0%). The 50 g powder was loaded on silica gel column and eluted with chloroform-methanol-water as eluents. From that, 16 mg pure saponin compound was isolated and analysed by thin layer chromatography using chloroform and methanol as the solvent systems. The structure of the purified triterpenoid fraction was established from infrared (IR), ultraviolet (UV), (1)H nuclear magnetic resonance (NMR), (13)C NMR and mass spectral data. The carbon skeleton of the compound was obtained by (13)C NMR spectroscopy. The chemical shift assignments obtained for gymnemagenol from (1)H NMR correspond to the molecular formula C(30)H(50)O(4). The compound was identified as 3β, 16β, 28, 29-tetrahydroxyolean-12-ene (gymnemagenol sapogenin). Parasite larvae were exposed to varying concentrations of purified compound gymnemagenol for 24 h. The results suggested that the larval mortality effects of the compound were 28%, 69%, 100% and 31%, 63%, 100% at 6, 12 and 24 h against A. subpictus and C. quinquefasciatus, respectively. In the present study, the per cent mortality were 100, 86, 67, 36, 21 and 100, 78, 59, 38 and 19 observed in the concentrations of 1,000, 500, 250, 125 and 62.75 ppm against the fourth-instar larvae of A. subpitcus and C. quinquefasciatus, respectively. The purified compound gymnemagenol was tested in concentrations of 80, 40, 20, 10 and 5 ppm, and the per cent mortality were 100, 72, 53, 30 and 15 against A. subpitcus and 100, 89, 61, 42 and 30 against C. quinquefasciatus, respectively. The larvicidal crude leaf extract of G. sylvestre showed the highest mortality in the concentration of 1,000 ppm against the larvae of A. subpictus (LC(50) = 166.28 ppm, r (2) = 0.807) and against the larvae of C. quinquefasciatus (LC(50) = 186.55 ppm, r (2) = 0.884), respectively. The maximum efficacy was observed in gymnemagenol compound with LC(50) and r (2) values against the larvae of A. subpictus (22.99 ppm, 0.922) and against C. quinquefasciatus (15.92 ppm, 0.854), respectively. The control (distilled water) showed nil mortality in the concurrent assay.

Infection and reinfection of Culex pipiens fatigans with Wuchereria bancrofti and the loss of mature larvae in blood-feeding*

PubMed Central

de Meillon, Botha; Hayashi, Shigeyo; Sebastian, Anthony

1967-01-01

Although previous workers had found no evidence of resistance to superinfection in vectors of filariasis, it was considered desirable to reinvestigate the subject because of the epidemiological implications, since a mosquito that can incubate to maturity successive broods of filarial larvae will obviously be a more efficient vector than one that cannot. The results obtained indicate that a Culex pipiens fatigans mosquito that picks up an infection early in its life can, by taking subsequent infecting feeds, remain infective for the rest of its life. The movement of mature larvae in the vector and losses of larvae during feeding are of interest since from this information one can estimate the probable number of larvae deposited on the host at each feed and the period of infectivity of the vector. In the present experiment there were, on average, 6.1 larvae per infective mosquito before a second blood-meal; after the meal the figure was 3.6. Thus, 41% of the original infective larvae were lost; not all would be inoculated into the host, as some would die on the surface of his skin. The release of infective larvae through blood-feeding results from a combination of the passive pressure of the engorged blood in the abdomen and the active movement of the larva itself. PMID:5298677

Larvicidal and repellent properties of Streptomyces sp. VITJS4 crude extract against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

PubMed

Naine, S Jemimah; Devi, C Subathra

2014-01-01

The aim of the present study was to assess the larvicidal and repellent properties of marine Streptomyces sp. VITJS4 crude extracts. The marine soil samples were collected from the Puducherry coast, Tamil Nadu, India. The isolate Streptomyces sp. VITJS4 was taxonomically characterized and identified. The ethyl acetate crude extract tested for larvicidal property showed 100% mortality for all the 3 species after 24 h exposure against the early fourth instar larvae of malarial vector--Anopheles stephensi at 50% and 90% lethal concentration (LC50 = 132.86, LC90 396.14 ppm); dengue vector--Aedes aegypti (LC50 = 112.78, LC90 336.42 ppm) and filariasis vector--Culex quinquefasciatus (LC50 = 156.53, LC90 468.37 ppm). The Streptomyces sp. VITJS4 solvent extracts of hexane, ethyl acetate, benzene, chloroform and methanol were tested for repellent activity against A. stephensi, A. aegypti and C. quinquefasciatus. The ethyl acetate extract showed complete protection for 210 min at 6 mg/cm2 against these mosquito bites. The crude extract was analyzed further for Fourier Transform-infrared spectroscopy (FT-IR) analysis. In addition to the importance of bioactive compounds, the utilization of Streptomyces sp. VITJS4 crude extracts revealed effective larvicidal and repellent activity against the vectors, which perhaps represents a promising tool in the management of mosquito control.

Crystal and solution structures of an odorant-binding protein from the southern house mosquito complexed with an oviposition pheromone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mao, Yang; Xu, Xianzhong; Xu, Wei

2010-11-15

Culex mosquitoes introduce the pathogens responsible for filariasis, West Nile virus, St. Louis encephalitis, and other diseases into humans. Currently, traps baited with oviposition semiochemicals play an important role in detection efforts and could provide an environmentally friendly approach to controlling their populations. The odorant binding proteins (OBPs) in the female's antenna play a crucial, if yet imperfectly understood, role in sensing oviposition cues. Here, we report the X-ray crystallography and NMR 3D structures of OBP1 for Culex quinquefasciatus (CquiOBP1) bound to an oviposition pheromone (5R,6S)-6-acetoxy-5-hexadecanolide (MOP). In both studies, CquiOBP1 had the same overall six-helix structure seen in othermore » insect OBPs, but a detailed analysis revealed an important previously undescribed feature. There are two models for OBP-mediated signal transduction: (i) direct release of the pheromone from an internal binding pocket in a pH-dependent fashion and (ii) detection of a pheromone-induced conformational change in the OBP {center_dot} pheromone complex. Although CquiOBP1 binds MOP in a pH-dependent fashion, it lacks the C terminus required for the pH-dependent release model. This study shows that CquiOBP binds MOP in an unprecedented fashion using both a small central cavity for the lactone head group and a long hydrophobic channel for its tail.« less

Larvicidal Activity of Essential Oils of Five Apiaceae Taxa and Some of Their Main Constituents Against Culex quinquefasciatus.

PubMed

Pavela, Roman; Maggi, Filippo; Cianfaglione, Kevin; Bruno, Maurizio; Benelli, Giovanni

2018-01-01

Apiaceae are aromatic herbs producing essential oils which are used on an industrial scale for various purposes. Notably, Apiaceae essential oils may replace synthetic insecticides keeping most of their efficacy and avoiding environmental pollution and human poisoning. In the present work, we explored the insecticidal potential of the essential oils from five Apiaceae taxa, namely Sison amomum, Echinophora spinosa, Heracleum sphondylium subsp. sphondylium, Heracleum sphondylium subsp. ternatum, and Trachyspemum ammi, as well as their major constituents (sabinene, p-cymene, terpinolene, myristicin, and thymol), against the filariasis vector Culex quinquefasciatus. For the purpose, the essential oils were obtained by hydrodistillation and their composition was achieved by gas chromatography/mass spectrometry (GC/MS). Their acute toxicity on third instar larvae of C. quinquefasciatus was determined. The two most active essential oils were those from T. ammi fruits and E. spinosa roots, showing LC 50 below 20 μl/l and LD 90 below 50 μl/l. These oils were dominated by the monoterpene phenol thymol and the phenylpropanoid myristicin, respectively, which showed the strongest larvicidal activity (LC 50 of 15.1 and 16.3 μl/l, respectively) among the pure compounds tested. These results showed that Apiaceae may be useful as source of larvicidal compounds to be used for the development of cheap, effective and eco-friendly insecticidal formulations. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

Repeat region of Brugia malayi sheath protein (Shp-1) carries Dominant B epitopes recognized in filarial endemic population.

PubMed

Jawaharlal, Jeya Prita Parasurama; Madhumathi, Jayaprakasam; Prince, Rajaiah Prabhu; Kaliraj, Perumal

2014-09-01

Transmission of lymphatic filariasis is mediated through microfilariae (L1 stage of the parasite) which is encased in an eggshell called sheath. The sheath protein Shp-1 stabilizes the structure due to the unique repeat region with Met-Pro-Pro-Gln-Gly sequences. Microfilarial proteins could be used as transmission blocking vaccines. Since the repeat region of Shp-1 was predicted to carry putative B epitopes, this region was used to analyze its reactivity with clinical samples towards construction of peptide vaccine. In silico analysis of Shp-1 showed the presence of B epitopes in the region 49-107. The polypeptide epitopic region Shp-149-107 was cloned and expressed in Escherichia coli. Antibody reactivity of the Shp-149-107 construct was evaluated in filarial endemic population by ELISA. Putatively immune endemic normals (EN) showed significantly high reactivity (P < 0.05) when compared to all the other categories. Antibody reactivity of Shp-1 repeat region was similar to that of whole protein proving that this region carries B epitopes responsible for its humoral response in humans. Thus this can be employed for inducing anti-microfilarial immunity in the infected population that may lead to reduction in transmission intensity and also it could be used along with other epitopes from different stages of the parasite in order to manage the disease effectively.

Male Mating Competitiveness of a Wolbachia-Introgressed Aedes polynesiensis Strain under Semi-Field Conditions

PubMed Central

Bossin, Hervé; Dobson, Stephen L.

2011-01-01

Background Lymphatic filariasis (LF), a global public health problem affecting approximately 120 million people worldwide, is a leading cause of disability in the developing world including the South Pacific. Despite decades of ongoing mass drug administration (MDA) in the region, some island nations have not yet achieved the threshold levels of microfilaremia established by the World Health Organization for eliminating transmission. Previously, the generation of a novel Aedes polynesiensis strain (CP) infected with an exogenous type of Wolbachia has been described. The CP mosquito is cytoplasmically incompatible (i.e., effectively sterile) when mated with wildtype mosquitoes, and a strategy was proposed for the control of A. polynesiensis populations by repeated, inundative releases of CP males to disrupt fertility of wild females. Such a strategy could lead to suppression of the vector population and subsequently lead to a reduction in the transmission of filarial worms. Methodology/Principal Findings CP males and F1 male offspring from wild-caught A. polynesiensis females exhibit near equal mating competitiveness with F1 females under semi-field conditions. Conclusions/Significance While laboratory experiments are important, prior projects have demonstrated the need for additional testing under semi-field conditions in order to recognize problems before field implementation. The results reported here from semi-field experiments encourage forward progression toward small-scale field releases. PMID:21829750

Landing response of Aedes (Stegomyia) polynesiensis mosquitoes to coloured targets.

PubMed

Chambers, E W; Bossin, H C; Ritchie, S A; Russell, R C; Dobson, S L

2013-09-01

Aedes polynesiensis Marks (Diptera: Culicidae) is the primary vector of lymphatic filariasis (LF) in the island countries and territories of the South Pacific. In the development of a novel control tool, the response of Ae. polynesiensis to six different colours (three solid fabrics, two patterned fabrics and a plastic tarp) was measured using a digital photographic system. Adult mosquitoes were placed into an environmental chamber and allowed to choose between a white target and one of six experimental targets. Mosquito landing frequency and landing duration were calculated. Adult female Ae. polynesiensis preferred all of the experimental targets to the white control target. Mosquito landing frequency was highest for the solid targets (black, navy blue and red) followed in turn by the two colour pattern targets and the polyethylene target. Mosquito landing duration was greater for experimental targets when compared with white control targets. Mosquito landing frequencies did not change over time during the course of the assay. The response of male Ae. polynesiensis was also measured when exposed to a 100% cotton black target. Male mosquitoes preferred the black target to the white control target, although at levels lower than that observed in female mosquitoes. The results suggest that future investigations evaluating the visual responses of Ae. polynesiensis mosquitoes are warranted, with a special emphasis on semi-field and field-based experiments. © 2013 The Royal Entomological Society.

In sickness or in health: TDR's partners. 6. The French Development Research Institute (ORSTOM).

PubMed

1997-10-01

One of the partner agencies working with the UN Development Program/World Bank/World Health Organization Special Programme for Research and Training in Tropical Diseases (TDR) is the French development research agency, ORSTOM. ORSTOM has been conducting research in intertropical regions for approximately 50 years with a particular focus on entomoparasitological aspects of vector-borne diseases. ORSTOM's close collaboration with TDR since the TDR Special Program was launched in 1975 has led to 1) improved knowledge about various aspects of trypanosomiasis that allowed identification of ways to control the epidemic; 2) reappraisal of the taxonomy of the parasitic protozoa responsible for Chagas disease and leishmaniasis; 3) improvements in the strategy to fight malaria; 4) assessment of the efficacy of ivermectin as a form of mass treatment for onchocerciasis; 5) improved knowledge about dracunculiasis that contributed to an eradication campaign; 6) expansion of the scope of biological control of bancroftian filariasis and other parasites; and 7) improved knowledge about ways to control two schistosome species. ORSTOM also participated in a training and structural enhancement initiative that resulted in creation of the Boake Medical and Veterinary Entomology Training Center. ORSTOM is currently undergoing a complete restructuring to respond to changes in international tropical disease research and to changing priorities that focus on vector-borne diseases, nutrition, AIDS, and health systems.

Entomopathogenic fungi for mosquito control: A review

PubMed Central

Scholte, Ernst-Jan; Knols, Bart G.J.; Samson, Robert A.; Takken, Willem

2004-01-01

Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti) curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis. PMID:15861235

[Screening of parasitic diseases in the asymptomatic immigrant population].

PubMed

Goterris, Lidia; Bocanegra, Cristina; Serre-Delcor, Núria; Moure, Zaira; Treviño, Begoña; Zarzuela, Francesc; Espasa, Mateu; Sulleiro, Elena

2016-07-01

Parasitic diseases suppose an important health problem in people from high endemic areas, so these must be discarded properly. Usually, these infections develop asymptomatically but, in propitious situations, are likely to reactivate themselves and can cause clinical symptoms and/or complications in the receiving country. Moreover, in some cases it is possible local transmission. Early diagnosis of these parasitic diseases made by appropriate parasitological techniques and its specific treatment will benefit both, the individual and the community. These techniques must be selected according to geoepidemiological criteria, patient's origin, migration route or time spent outside the endemic area; but other factors must also be considered as its sensitivity and specificity, implementation experience and availability. Given the high prevalence of intestinal parasites on asymptomatic immigrants, it is recommended to conduct a study by coproparasitological techniques. Because of its potential severity, the screening of asymptomatic malaria with sensitive techniques such as PCR (polymerase chain reaction) is also advisable. Serological screening for Chagas disease should be performed on all Latin American immigrants, except for people from the Caribbean islands. Other important parasites, which should be excluded, are filariasis and urinary schistosomiasis, by using microscopic examination. The aim of this paper is to review the different techniques for the screening of parasitic diseases and its advices within the care protocols for asymptomatic immigrants. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

Seroprevalence of five neglected parasitic diseases among immigrants accessing five infectious and tropical diseases units in Italy: a cross-sectional study.

PubMed

Martelli, G; Di Girolamo, C; Zammarchi, L; Angheben, A; Morandi, M; Tais, S; Degani, M; El Hamad, I; Caligaris, S; Ciannameo, A; Grilli, E; Urbinati, L; Monteiro, G B; Scarcella, C; Petrosillo, N; Digaetano, M; Rabbi, L; Bazzanini, N; Cacciatore, F; Marta, B L; Moro, M L; Bartoloni, A; Viale, P; Verucchi, G

2017-05-01

This multicentre cross-sectional study aims to estimate the prevalence of five neglected tropical diseases (Chagas disease, filariasis, schistosomiasis, strongyloidiasis and toxocariasis) among immigrants accessing health care facilities in five Italian cities (Bologna, Brescia, Florence, Rome, Verona). Individuals underwent a different set of serological tests, according to country of origin and presence of eosinophilia. Seropositive patients were treated and further followed up. A total of 930 adult immigrants were enrolled: 477 men (51.3%), 445 women (47.9%), eight transgender (0.8%); median age was 37.81 years (range 18-80 years). Most of them had come from the African continent (405/930, 43.5%), the rest from East Europe, South America and Asia, and 9.6% (89/930) were diagnosed with at least one of the infections under study. Seroprevalence of each specific infection varied from 3.9% (7/180) for Chagas disease to 9.7% (11/113) for toxocariasis. Seropositive people were more likely to be 35-40 years old and male, and to come from South East Asia, sub-Saharan Africa or South America. The results of our study confirm that neglected tropical diseases represent a substantial health problem among immigrants and highlight the need to address this emerging public health issue. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Insights from agriculture for the management of insecticide resistance in disease vectors.

PubMed

Sternberg, Eleanore D; Thomas, Matthew B

2018-04-01

Key to contemporary management of diseases such as malaria, dengue, and filariasis is control of the insect vectors responsible for transmission. Insecticide-based interventions have contributed to declines in disease burdens in many areas, but this progress could be threatened by the emergence of insecticide resistance in vector populations. Insecticide resistance is likewise a major concern in agriculture, where insect pests can cause substantial yield losses. Here, we explore overlaps between understanding and managing insecticide resistance in agriculture and in public health. We have used the Global Plan for Insecticide Resistance Management in malaria vectors, developed under the auspices of the World Health Organization Global Malaria Program, as a framework for this exploration because it serves as one of the few cohesive documents for managing a global insecticide resistance crisis. Generally, this comparison highlights some fundamental differences between insect control in agriculture and in public health. Moreover, we emphasize that the success of insecticide resistance management strategies is strongly dependent on the biological specifics of each system. We suggest that the biological, operational, and regulatory differences between agriculture and public health limit the wholesale transfer of knowledge and practices from one system to the other. Nonetheless, there are some valuable insights from agriculture that could assist in advancing the existing Global Plan for Insecticide Resistance Management framework.

[Ivermectin as an adjunct in the treatment of refractory epilepsy].

PubMed

Diazgranados-Sanchez, J A; Mejia-Fernandez, J L; Chan-Guevara, L S; Valencia-Artunduaga, M H; Costa, J L

2017-10-01

Ivermectin, a 22'23 dihydro derivative of avermectins beta-1a, is a highly effective veterinary and human anti parasitic, used to treat endoparasites of difficult control such as filariasis and onchocerciasis, with a median plasma life of at least of 16 hours. The recommended therapeutic doses range from 0.05 to 0.40 mg/kg, without undesirable effects or risk to human life. It went from being a great success in animal health to its application in humans, where it has had great impact. Studies in basic sciences have shown that ivermectin has anticonvulsive effects in different epileptic animal models, where five different mechanisms of action have been described. Descriptive, prospective observational study, performed between 2013 and 2015, with 32 refractory epileptic patients, who received ivermectin as an a dose of adjunctive treatment of 10 mg/day three or seven times a week, controlled every three months, followed by 12-24 months, without withdrawal of anticonvulsant medications that they received previously. Progressively, patients entered into crisis control, at the end of the programmed follow-up period, the total percentage of crisis reduction was 97%, of which 57% did not return to crisis from the beginning of treatment, all patients being free of crisis according to International League Against Epilepsy criteria. Ivermectin has been useful as an adjuvant, achieving a significant decrease in seizures in this group of drug resistant patients.

Carica papaya (Papaya) latex: a new paradigm to combat against dengue and filariasis vectors Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

PubMed

Chandrasekaran, Rajkuberan; Seetharaman, Prabukumar; Krishnan, Muthukumar; Gnanasekar, Sathishkumar; Sivaperumal, Sivaramakrishnan

2018-02-01

This study manifests the larvicidal efficacy of Carica papaya latex extract and silver nanoparticles (CPAgNPs) synthesized using latex, against developing immature juveniles of Aedes aegypti and Culex quinquefasciatus . Briefly, the latex was collected and fractioned with different solvents such as chloroform, methanol and aqueously. The obtained crude extracts were subjected to larvicidal activity in the dose-dependent method. After 24 h, the mortality rate was calculated and statistically analyzed. From the results, it was demonstrated that the chloroform extract displayed prominent activity in IInd and IIIrd instar larvae of A. aegypti and C. quinquefasciatus with better LC 50 values followed by methanol and aqueous extract. Subsequently, we profiled the qualitative analysis of a chloroform extract through biochemical tests; Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry. Moreover, we authenticated the major secondary metabolites and activated larvicidal compound present in the extract. Further, we synthesized CPAgNPs using aqueous latex extract and challenged with IInd and IIIrd instar larvae of A. aegypti and C. quinquefasciatus. Noticeably, the synthesized nanoproducts were showed 100% mortality in a 24-h treatment with significant LC 50 values. Hence, this study has opened up new vistas in the field of parasitological research to develop Carica papaya latex as a new stratagem in the insect vector management program.

Efficacy of three formulations of diflubenzuron, an insect growth regulator, against Culex quinquefasciatus Say, the vector of Bancroftian filariasis in India

PubMed Central

Sadanandane, C.; Doss, P. S. Boopathi; Jambulingam, P.

2012-01-01

Background & objectives: Insect growth regulators (IGRs) offer alternatives to conventional chemical larvicides that pose problem of resistance and environmental safety. However, only a limited number of IGRs have been approved for use in mosquito control. In the present study, two new formulations of the IGR diflubenzuron, 2 per cent granular (GR) and 2 per cent tablet (DT) were tested for its efficacy against Culex quinquefasciatus, in comparison to its 25 per cent wettable powder (WP) formulation. Methods: The WP, GR and DT formulations were tested in cesspits, street drains and abandoned wells each at four dosages, 25, 50, 75 and 100 g ai/ha. Additionally, the DT formulation was tested at a higher dosage of 1 tablet/m2 (equal to 400 g ai/ha). Results: The WP and GR formulations yielded >80 per cent inhibition of adult emergence (IE) for 7-10 days in cesspits, 4-7 days in street drains and 7-21 days in abandoned wells at all dosages tested. The DT formulation was effective only at higher dosage 100 g ai/ha and or 1 tablet/m2 for 7-15 days at all habitats. Interpretation & conclusions: The trial showed that the dosage 25 g ai/ha of 25 per cent WP could be the field dosage for cesspits and wells, and 50 g ai/ha for drains, to be applied at weekly intervals. The dosages 25, 50 and 100 g ai/ha of 2 per cent GR could be the field dosages for application in cesspits at weekly intervals, in abandoned wells every three weeks and in drains at weekly intervals, respectively. Diflubenzuron 25 per cent WP and 2 per cent GR could be used for larval control of Cx. quinquefasciatus under integrated vector management programme. PMID:23287125

Global trends in neglected tropical disease control and elimination: impact on child health.

PubMed

Barry, Meagan A; Simon, Gregory G; Mistry, Neeraj; Hotez, Peter J

2013-08-01

The neglected tropical diseases (NTDs) are a group of 17 lesser known chronic infections which predominantly affect poor and disenfranchised communities. There are a number of NTDs that cause significant global morbidity in children, including the three major soil transmitted helminth (STH) infections (ascariasis, trichuriasis and hookworm infection), schistosomiasis and trachoma. These NTDs, together with lymphatic filariasis and onchocerciasis, are currently being targeted for global control and elimination through mass drug administration (MDA) campaigns. They represent the most common NTDs and share significant geographical overlap. Additionally, many individuals are polyparasitised with more than a single NTD. Integrated NTD control and elimination MDA programmes offer safe and efficacious treatments for all seven NTDs. However, the current global level of MDA coverage for the leading childhood NTDs, that is, STH infections, schistosomiasis and trachoma, remains well under 50%. Limiting factors for global coverage include insufficient global financial support, drug donation capacity of pharmaceutical companies and targeting school age children to the exclusion of other age groups in need of treatment, such as preschool age children. There is also a need for development of novel prevention and treatment modalities, such as next-generation small molecule drugs and vaccines. Efforts are underway to harness the momentum of a 2012 London Declaration on NTDs and a 2013 World Health Assembly (WHA) resolution as a means to control or in some cases eliminate by 2020 these NTDs that affect children worldwide.

Remote Sensing, GIS, and Vector-Borne Disease

NASA Technical Reports Server (NTRS)

Beck, Louisa R.

2001-01-01

The concept of global climate change encompasses more than merely an alteration in temperature; it also includes spatial and temporal covariations in precipitation and humidity, and more frequent occurrence of extreme weather events. The impact of these variations, which can occur at a variety of temporal and spatial scales, could have a direct impact on disease transmission through their environmental consequences for pathogen, vector, and host survival, as well as indirectly through human demographic and behavioral responses. New and future sensor systems will allow scientists to investigate the relationships between climate change and environmental risk factors at multiple spatial, temporal and spectral scales. Higher spatial resolution will provide better opportunities for mapping urban features previously only possible with high resolution aerial photography. These opportunities include housing quality (e.g., Chagas'disease, leishmaniasis) and urban mosquito habitats (e.g., dengue fever, filariasis, LaCrosse encephalitis). There are or will be many new sensors that have higher spectral resolution, enabling scientists to acquire more information about parameters such as soil moisture, soil type, better vegetation discrimination, and ocean color, to name a few. Although soil moisture content is now detectable using Landsat, the new thermal, shortwave infrared, and radar sensors will be able to provide this information at a variety of scales not achievable using Landsat. Soil moisture could become a key component in transmission risk models for Lyme disease (tick survival), helminthiases (worm habitat), malaria (vector-breeding habitat), and schistosomiasis (snail habitat).

Beyond providing drugs: the Mectizan® donation stimulates new strategies in service delivery and in strengthening health systems.

PubMed

Hopkins, Adrian

2012-05-01

The donation of Mectizan® by Merck & Co Inc. in 1987 "as much as was needed for as long as was needed for onchocerciasis control" was a major change from traditional corporate drug donations. The company realised that those who needed the drug most would never be able to purchase it, and so gave it away. The donation enabled the Onchocerciasis Control Programme in West Africa to add Mectizan distribution to its ongoing control strategy. For the first time there was hope for those living in other areas of Africa, Latin America and Yemen. Governments and non-governmental development organizations quickly got together to begin treatment in these new areas. Two new programmes and partnerships were created; the African Programme for Onchocerciasis Control and the Onchocerciasis Elimination Programme for the Americas. These programmes have been in the forefront of developing new strategies, including the Community Directed approach, which has now expanded into other disease control programmes at the community level, such as Vitamin A distribution and malaria control. This donation has led not only to the probability of elimination of onchocerciasis in the Americas in the near future, but is stimulating approaches to the elimination in Africa, in areas considered impossible five years ago. Other major pharmaceutical donations have followed, initiating the plan to eliminate lymphatic filariasis worldwide, and also stimulating interest in controlling other "neglected tropical diseases," which affect the poorest billion of the world's population, making this now a reality.

Identification of anti-filarial leads against aspartate semialdehyde dehydrogenase of Wolbachia endosymbiont of Brugia malayi: combined molecular docking and molecular dynamics approaches.

PubMed

Amala, Mathimaran; Rajamanikandan, Sundaraj; Prabhu, Dhamodharan; Surekha, Kanagarajan; Jeyakanthan, Jeyaraman

2018-02-06

Lymphatic filariasis is a debilitating vector borne parasitic disease that infects human lymphatic system by nematode Brugia malayi. Currently available anti-filarial drugs are effective only on the larval stages of parasite. So far, no effective drugs are available for humans to treat filarial infections. In this regard, aspartate semialdehyde dehydrogenase (ASDase) in lysine biosynthetic pathway from Wolbachia endosymbiont Brugia malayi represents an attractive therapeutic target for the development of novel anti-filarial agents. In this present study, molecular modeling combined with molecular dynamics simulations and structure-based virtual screening were performed to identify potent lead molecules against ASDase. Based on Glide score, toxicity profile, binding affinity and mode of interactions with the ASDase, five potent lead molecules were selected. The molecular docking and dynamics results revealed that the amino acid residues Arg103, Asn133, Cys134, Gln161, Ser164, Lys218, Arg239, His246, and Asn321 plays a crucial role in effective binding of Top leads into the active site of ASDase. The stability of the ASDase-lead complexes was confirmed by running the 30 ns molecular dynamics simulations. The pharmacokinetic properties of the identified lead molecules are in the acceptable range. Furthermore, density functional theory and binding free energy calculations were performed to rank the lead molecules. Thus, the identified lead molecules can be used for the development of anti-filarial agents to combat the pathogenecity of Brugia malayi.

"Wonders unconceived": reflections on the birth of medical entomology.

PubMed

Cirillo, Vincent J

2011-01-01

Prior to Patrick Manson's discovery in 1877 that the mosquito Culex fatigans was the intermediate host of filariasis, the association of insects with disease and the nature of disease transmission was almost entirely speculation. Manson's work was incomplete, however, because it showed the manner in which the mosquito acquired the infection from humans, but failed to show the way in which the mosquito passed the infection to humans. That pathogens were transmitted by the bite of an infected female mosquito was later proven experimentally with bird malaria by Manson's protégé, Ronald Ross. In 1898 Ross demonstrated that the infective stage of the malarial parasite was injected into the host when the mosquito released saliva into the wound prior to injesting blood. Insects were suspected as carriers of disease for centuries, yet it was not until the late 1870s that the uncritical acceptance of folk beliefs was supplanted by research-based scientific medicine. Why did it take so long? The answer lies in the fact that early medicine itself was imprecise and could not have pursued the subject with any hope of useful results until the last quarter of the 19th century. A better understanding of the nature of the disease process (germ theory of disease) and improved technology (microscopes and oil-immersion lenses with greater resolving power, and synthetic tissue stains) were indispensable for revealing the nexus between those partners in crime: insects and parasites.

Heme acquisition in the parasitic filarial nematode Brugia malayi.

PubMed

Luck, Ashley N; Yuan, Xiaojing; Voronin, Denis; Slatko, Barton E; Hamza, Iqbal; Foster, Jeremy M

2016-10-01

Nematodes lack a heme biosynthetic pathway and must acquire heme from exogenous sources. Given the indispensable role of heme, this auxotrophy may be exploited to develop drugs that interfere with heme uptake in parasites. Although multiple heme-responsive genes (HRGs) have been characterized within the free-living nematode Caenorhabditis elegans, we have undertaken the first study of heme transport in Brugia malayi, a causative agent of lymphatic filariasis. Through functional assays in yeast, as well as heme analog, RNAi, and transcriptomic experiments, we have shown that the heme transporter B. malayi HRG-1 (BmHRG-1) is indeed functional in B. malayi In addition, BmHRG-1 localizes both to the endocytic compartments and cell membrane when expressed in yeast cells. Transcriptomic sequencing revealed that BmHRG-1, BmHRG-2, and BmMRP-5 (all orthologs of HRGs in C. elegans) are down-regulated in heme-treated B. malayi, as compared to non-heme-treated control worms. Likely because of short gene lengths, multiple exons, other HRGs in B. malayi (BmHRG-3-6) remain unidentified. Although the precise mechanisms of heme homeostasis in a nematode with the ability to acquire heme remains unknown, this study clearly demonstrates that the filarial nematode B. malayi is capable of transporting exogenous heme.-Luck, A. N., Yuan, X., Voronin, D., Slatko, B. E., Hamza, I., Foster, J. M. Heme acquisition in the parasitic filarial nematode Brugia malayi. © The Author(s).

Heme acquisition in the parasitic filarial nematode Brugia malayi

PubMed Central

Luck, Ashley N.; Yuan, Xiaojing; Voronin, Denis; Slatko, Barton E.; Hamza, Iqbal; Foster, Jeremy M.

2016-01-01

Nematodes lack a heme biosynthetic pathway and must acquire heme from exogenous sources. Given the indispensable role of heme, this auxotrophy may be exploited to develop drugs that interfere with heme uptake in parasites. Although multiple heme-responsive genes (HRGs) have been characterized within the free-living nematode Caenorhabditis elegans, we have undertaken the first study of heme transport in Brugia malayi, a causative agent of lymphatic filariasis. Through functional assays in yeast, as well as heme analog, RNAi, and transcriptomic experiments, we have shown that the heme transporter B. malayi HRG-1 (BmHRG-1) is indeed functional in B. malayi. In addition, BmHRG-1 localizes both to the endocytic compartments and cell membrane when expressed in yeast cells. Transcriptomic sequencing revealed that BmHRG-1, BmHRG-2, and BmMRP-5 (all orthologs of HRGs in C. elegans) are down-regulated in heme-treated B. malayi, as compared to non–heme-treated control worms. Likely because of short gene lengths, multiple exons, other HRGs in B. malayi (BmHRG-3–6) remain unidentified. Although the precise mechanisms of heme homeostasis in a nematode with the ability to acquire heme remains unknown, this study clearly demonstrates that the filarial nematode B. malayi is capable of transporting exogenous heme.—Luck, A. N., Yuan, X., Voronin, D., Slatko, B. E., Hamza, I., Foster, J. M. Heme acquisition in the parasitic filarial nematode Brugia malayi. PMID:27363426

Species differences in hepatic biotransformation of the anthelmintic drug flubendazole.

PubMed

Maté, M L; Geary, T; Mackenzie, C; Lanusse, C; Virkel, G

2017-10-01

Flubendazole (FLBZ) is a broad-spectrum benzimidazole anthelmintic used in pigs, poultry, and humans. It has been proposed as a candidate for development for use in elimination programmes for lymphatic filariasis and onchocerciasis in humans. Moreover, FLBZ has shown promise in cancer chemotherapy, particularly for neuroblastoma. This work investigated the hepatic carbonyl-reducing pathway of FLBZ in different species, including humans. Microsomal and cytosolic fractions were obtained from sheep, cattle, pig, hen, rat, and human liver. Both subcellular fractions of each species converted FLBZ into a reduced metabolite (red-FLBZ). The rate of microsomal red-FLBZ production was highest in sheep (1.92 ± 0.13 nmol/min.mg) and lowest in pigs (0.04 ± 0.02 nmol/min.mg); cytosolic red-FLBZ production ranged from 0.02 ± 0.01 (pig) to 1.86 ± 0.61 nmol/min.mg (sheep). Only subcellular fractions from sheep liver oxidized red-FLBZ to FLBZ in a NADP + -dependent oxidative reaction. Liver microsomes from both pigs and humans transformed FLBZ to red-FLBZ and a hydrolyzed metabolite. Very significant differences in the pattern of FLBZ metabolism were observed among the tested species and humans. These results reinforce the need for caution in extrapolating data on metabolism, efficacy, and safety of drugs derived from studies performed in different species. © 2017 John Wiley & Sons Ltd.

Social stigma towards neglected tropical diseases: a systematic review.

PubMed

Hofstraat, Karlijn; van Brakel, Wim H

2016-03-01

People affected by neglected tropical diseases (NTDs) are frequently the target of social stigmatization. To date not much attention has been given to stigma in relation to NTDs. The objective of this review is to identify the extent of social stigma and the similarities and differences in the causes, manifestations, impact of stigma and interventions used between the NTDs. A systematic review was conducted in Pubmed, ScienceDirect, PsycINFO and Web of Knowledge. The search encompassed 17 NTDs, including podoconiosis, but not leprosy as this NTD has recently been reviewed. However, leprosy was included in the discussion. The 52 selected articles provided evidence on stigma related to lymphatic filariasis (LF), podoconiosis, Buruli ulcer, onchocerciasis, schistosomiasis, leishmaniasis, Chagas disease, trachoma, soil-transmitted helminthiasis (STH) and human African trypanosomiasis. The similarities predominated in stigma related to the various NTDs; only minimal differences in stigma reasons and measures were found. These similarities suggest that joint approaches to reduce stigmatization may be feasible. Lessons from leprosy and other stigmatized health conditions can be used to plan such joint approaches. Further research will be necessary to study the efficacy of joint interventions and to investigate stigma related to NTDs for which no evidence is available yet. © The Author 2016. 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.

Human Parasitology and Parasitic Diseases: Heading Towards 2050.

PubMed

Hotez, Peter J

2018-01-01

By 2050 our civilized planet may be comprised predominantly of networked megacities embedded in warm subtropical and tropical climates, and under stress from climate change and catastrophic weather events. Urban slum areas in these cities, including those found in wealthier middle- and high-income nations (blue marble health), will be especially vulnerable to disease. Moreover, regional conflicts fought over shifting and limited resources, including water, will collapse health systems infrastructures to further promote disease emergence and reemergence. Thus while by 2050 we might congratulate ourselves for successfully eliminating some key parasitic and neglected tropical diseases such as dracunculiasis, lymphatic filariasis, onchocerciasis, and human African trypanosomiasis, there could be a commensurate rise in other parasitic diseases based on the scenarios highlighted above. Of particular concern are urban and newly urbanized helminth infections, including schistosomiasis and some soil-transmitted helminth infections, as well zoonotic helminthiases, such as toxocariasis, food-borne trematodiases, and cysticercosis. Protozoan infections persisting in urban environments, including leishmaniasis, Chagas disease, malaria, and intestinal protozoan infections, will also remain, as will zoonotic diseases such as toxoplasmosis. Our best hope to counteract the parasitic diseases emerging in our steaming 21st century megacities is to develop new and innovative technologies through gene editing, systems biology, and immunology, and the new single-celled OMICs. However, success on this front will require our ability to contain the globalization of antiscience beliefs and sentiments. © 2018 Elsevier Ltd All rights reserved.

Bore holes and the vanishing of guinea worm disease in Ghana's upper region.

PubMed

Hunter, J M

1997-07-01

Ghana's Upper Region provides an excellent example of the beneficial effects of improved water security provided by hand-pump tube wells. Following a Ghana-Canada bilateral development project that installed some 2500 pumps, protection rates against guinea worm disease may be estimated as 88% in the west, and 96% in the east. Survey comparisons between ca 1960 and 1990 show that dracunculiasis declined in 32 of a total of 38 areas. The shadow of guinea worm has been lifted from the land and, in many areas, a true "vanishing" has occurred. The few areas of disease increase are characterized by the lowest population densities, pioneer settlement for cotton farming, and an absence of bore holes. Vagaries of development have inadvertently produced disease transformations or "metamorphoses" from dracunculiasis to elephantiasis (lymphatic filariasis) in one area, and to red water disease (schistosomiasis hematobium) in other areas. Correlative associations between pump densities and guinea worm disease are weakened by the large size of areas for which disease is reported in 1990. One preliminary finding is that geographical distance to the pump is a stronger influence than demographic pressure on pumps, regarding dracunculiasis. Diminishing returns on higher pump densities in many areas support the idea of making fuller, safer use of supplementary non-pump water. Despite crises of fee payment and pump maintenance, the rural bore hole project has struck a mortal blow against guinea worm, and permanently raised the quality of life in the Upper Region.

Base-line village health profiles in the E.Y.N rural health programme area of north-east Nigeria.

PubMed

Dixon, R A; Thompson, J S

1993-06-01

In order to document the health profile of rural farming communities not yet reached by the EYN Rural Health Programme, based at Garkida, Nigeria, four villages were surveyed by a Sheffield medical student who lived for several weeks in each village, working alongside local women. Villagers helped in separate surveys of village environment and water sources, of compound (household) hygiene, of male heads of compounds, of women of childbearing age, and of children. Stagnant rain-water ponds and widespread animal faeces litter were the main village environmental hazards and hardly any satisfactory pit latrines were seen. One person in nearly 2000 surveyed treated the drinking water. Infant mortality was estimated at 200 per 1000. Commonly reported health problems included abdominal pain, coughs and colds, filariasis, diarrhoea, scabies, worms, blood in stool, fever, back pain and eye infections. In each village fewer than 20% of the men and fewer than 10% of the women had received any education. Average completed family size was 6 or 7 children per woman with 3 other non-surviving children. The causes of malaria and of diarrhoea were each known by fewer than 10% of mothers in each village. About a quarter of the under fives had suffered from diarrhoea in the past fortnight, a quarter had received any immunisation and one fifth were at least mildly malnourished. One quarter of children aged 6-12 years attended school.

Can coverage of schistosomiasis and soil transmitted helminthiasis control programmes targeting school-aged children be improved? New approaches.

PubMed

Massa, K; Olsen, A; Sheshe, A; Ntakamulenga, R; Ndawi, B; Magnussen, P

2009-11-01

Control programmes generally use a school-based strategy of mass drug administration to reduce morbidity of schistosomiasis and soil-transmitted helminthiasis (STH) in school-aged populations. The success of school-based programmes depends on treatment coverage. The community-directed treatment (ComDT) approach has been implemented in the control of onchocerciasis and lymphatic filariasis in Africa and improves treatment coverage. This study compared the treatment coverage between the ComDT approach and the school-based treatment approach, where non-enrolled school-aged children were invited for treatment, in the control of schistosomiasis and STH among enrolled and non-enrolled school-aged children. Coverage during the first treatment round among enrolled children was similar for the two approaches (ComDT: 80.3% versus school: 82.1%, P=0.072). However, for the non-enrolled children the ComDT approach achieved a significantly higher coverage than the school-based approach (80.0 versus 59.2%, P<0.001). Similar treatment coverage levels were attained at the second treatment round. Again, equal levels of treatment coverage were found between the two approaches for the enrolled school-aged children, while the ComDT approach achieved a significantly higher coverage in the non-enrolled children. The results of this study showed that the ComDT approach can obtain significantly higher treatment coverage among the non-enrolled school-aged children compared to the school-based treatment approach for the control of schistosomiasis and STH.

Control of scabies, skin sores and haematuria in children in the Solomon Islands: another role for ivermectin.

PubMed Central

Lawrence, Gregor; Leafasia, Judson; Sheridan, John; Hills, Susan; Wate, Janet; Wate, Christine; Montgomery, Janet; Pandeya, Nirmala; Purdie, David

2005-01-01

OBJECTIVE: To assess the effects of a 3-year programme aimed at controlling scabies on five small lagoon islands in the Solomon Islands by monitoring scabies, skin sores, streptococcal skin contamination, serology and haematuria in the island children. METHODS: Control was achieved by treating almost all residents of each island once or twice within 2 weeks with ivermectin (160-250 microg/kg), except for children who weighed less than 15 kg and pregnant women, for whom 5% permethrin cream was used. Reintroduction of scabies was controlled by treating returning residents and visitors, whether or not they had evident scabies. FINDINGS: Prevalence of scabies dropped from 25% to less than 1% (P < 0.001); prevalence of sores from 40% to 21% (P < 0.001); streptococcal contamination of the fingers in those with and without sores decreased significantly (P = 0.02 and 0.047, respectively) and anti-DNase B levels decreased (P = 0.002). Both the proportion of children with haematuria and its mean level fell (P = 0.002 and P < 0.001, respectively). No adverse effects of the treatments were seen. CONCLUSION: The results show that ivermectin is an effective and practical agent in the control of scabies and that control reduces the occurrence of streptococcal skin disease and possible signs of renal damage in children. Integrating community-based control of scabies and streptococcal skin disease with planned programmes for controlling filariasis and intestinal nematodes could be both practical and produce great health benefits. PMID:15682247

[Sensibility of Entamoeba histolytica trophozoites to ivermectin].

PubMed

González-Salazar, Francisco; Mata-Cárdenas, Benito D; Vargas-Villareal, Javier

2009-01-01

Amebiasis caused by Entamoeba histolytica is a problem of public world health. The most frequent clinical presentation are the dysentery and the amebic liver abscess. Fifty millions of cases and more than 100.000 deaths for this disease are reported annually worldwide. The life cycle of E. histolytica has two phases: trophozoite and cyst. Trophozoites are the causal agent of disease. The effective treatment for the amebiasis includes drugs with serious collateral effects. Ivermectin is a macrolid with activity against endoparasites and ectoparasites causing strongiloidosis, filariasis, oncocercosis, scabiasis and pediculosis. The use of ivermectin has been extended almost worldwide; it is recognized as a safe drug. The main objective of this study was to determine in vitro sensibility of trophozoites of E. histolytica was to the treatment with ivermectin. To determine the sensibility of the parasites to the drug, E. histolytica was cultivated in PEHPS medium. During its logarithmic growth phase the trophozoites were exposed to different concentrations of ivermectin. As controls other antiparasitic drugs were used. For each drug, serial dilutions were prepared, and mixed in culture tubes with parasites (2 x 104 cells/ml). They were incubated for 72 h and then the percentage of growth inhibition was calculated by Probit analysis. Ivermectin showed activity against trophozoites of E. histolytica. The 50% of growth inhibition of ivermectin was 6.40 mg/ml. This dose was higher than for other anti parasitic drugs. Its activity in vivo in animal models remains to be demonstrated.

Occurrence of filaria in domestic dogs of Samburu pastoralists in Northern Kenya and its associations with canine distemper.

PubMed

Albrechtová, Kateřina; Sedlák, Kamil; Petrželková, Klára J; Hlaváč, Jan; Mihalca, Andrei D; Lesingirian, Alison; Kanyari, Paul W N; Modrý, David

2011-12-15

Samples of blood (serum, smears and blood preserved with ethanol) were collected from dogs during a vaccination campaign in northern Kenya in the years 2006 and 2007. Blood was screened for filarial parasites using molecular and microscopy methods and sera were tested for antibodies against canine distemper virus (CDV). Parasitological examination revealed the presence of two species of canine filariae: Acanthocheilonema dracunculoides and A. reconditum. The DNA from the former species was detected in 58% dogs sampled in 2006 and 36% dogs sampled in 2007, whereas the latter was found only in 4.2% samples collected in 2007. Microfilariae were found in 33.8% blood smears collected in 2006 and 10.6% blood smears collected in 2007. The seroprevalence of CDV was 33.4% in 2006 and 11.2% in 2007. The effect of sex, age and CDV-seropositivity/seronegativity on the occurrence of A. dracunculoides was evaluated. Infection by A. dracunculoides was more common in males and in dogs with a positive antibody titer for canine distemper, but evenly distributed among different age groups. The difference in the prevalence of A. dracunculoides in two isolated mountain ranges was not statistically significant. Methodologies available for detection and determination of canine filariae are compared, underlining methodical pitfalls arising through the determination of less common filarial species. The role of single epidemiological factors and possible association between canine distemper and filariasis are discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

Randomised controlled clinical trial of increased dose and frequency of albendazole and ivermectin on Wuchereria bancrofti microfilarial clearance in northern Malawi.

PubMed

Tafatatha, Terence T; Ngwira, Bagrey M; Taegtmeyer, Miriam; Phiri, Amos J; Wilson, Trevor P; Banda, Louis G; Piston, Wilson N; Koole, Olivier; Horton, John; French, Neil

2015-06-01

In Africa, albendazole and ivermectin are currently used in combination for annual mass drug administration (MDA) for lymphatic filariasis (LF) elimination. Rapid and sustained clearance is desirable for public health impact and elimination of LF. Increasing the dose and/or frequency of albendazole and ivermectin treatment may be more effective in clearing microfilariae than standard MDA. We conducted a randomised controlled open label trial in northern Malawi comparing three modified treatment groups to standard dosage of ivermectin and albendazole in adults with confirmed circulating LF antigen and microfilaria. Participants were followed-up every 6 months for 2 years for repeat microfilarial counts and safety assessments. A total of 1851 adults were screened and 70 with microfilarial counts >80 microfilariae/ml were randomised. All treatment groups achieved a significant reduction of microfilariae levels by 12- and 24-months of follow-up. Doubling the standard dose and administering it twice yearly showed a non-significant tendency towards faster and more complete clearance. There were no serious adverse reactions. In this small study, all regimens effectively cleared microfilaria. Standard treatment may be adequate in settings like Malawi but not in all endemic settings and larger studies are required to demonstrate benefit of higher dosages. [ClinicalTrials.gov identifier: NCT01213576]. © The Author 2015. 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.

Phytosynthesis of silver nanoparticles using aqueous leaf extracts of Lippia citriodora: Antimicrobial, larvicidal and photocatalytic evaluations.

PubMed

Elemike, Elias E; Onwudiwe, Damian C; Ekennia, Anthony C; Ehiri, Richard C; Nnaji, Nnaemeka J

2017-06-01

Nanoscience and nanotechnology represent new and enabling platforms that promise to provide broad range of novel and improved technologies for environmental, biological and other scientific applications. This study reports the synthesis of silver nanoparticles mediated by aqueous leaf extract of Lippia citriodora at two different temperatures of 50°C and 90°C. The synthesis of colloidal silver nanoparticles (AgNPs) was monitored by the use of UV-visible spectroscopy at different temperatures and time intervals. The surface plasmon bands (SPBs) showed peaks between 417 and 421nm at 90°C and around 430nm at 50°C, indicating a red shift at lower temperature. Fourier transform infrared (FTIR) analysis of the nanoparticles showed the presence of similar peaks found in the spectra of the plant extract. The size of the AgNPs was confirmed by transmission electron microscopy (TEM) which indicated an average size of 23.8nm (90°C) and 25nm (50°C). The nanoparticles showed better antimicrobial activities when compared to the crude plant extract against several screened pathogens: Gram negative (Escherichia coli, and Salmonella typhi) and Gram positive (Bacillus subtilis and Staphylococcus aureus) strains and a fungi organism; Candida albicans. In addition, the AgNPs showed good larvicidal efficacy against early 4th instar of Culex quinquefasciatus (a vector of lymphatic filariasis). Finally, the nanoparticles exhibited photocatalytic properties on an industrial waste pollutant, methylene blue. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of right ventricular Tei index (index of myocardial performance) in healthy dogs and dogs with tricuspid regurgitation.

PubMed

Teshima, Kenji; Asano, Kazushi; Iwanaga, Koji; Koie, Hiroshi; Uechi, Masami; Kato, Yuka; Kutara, Kenji; Edamura, Kazuya; Hasegawa, Atsuhiko; Tanaka, Shigeo

2006-12-01

Right ventricular (RV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating RV function in various human cardiac diseases. The purposes of this study were to validate the correlation between RV Tei index and RV function obtained by cardiac catheterization in healthy dogs, and to evaluate the RV Tei index in dogs with tricuspid regurgitation (TR). In healthy dogs, the RV Tei index significantly correlated with the RV peak +dP/dt (r=-0.80, p<0.0001) and -dP/dt (r=0.69, p=0.0001). In normal dogs, the RV Tei index was not significantly correlated with heart rate, body weight, and age. The RV Tei index significantly increased in dogs with moderate to severe TR (0.39 +/- 0.35, p=0.0015), filariasis (0.46 +/- 0.16, p=0.0131), and trivial to mild TR and severe mitral regurgitation (MR; 0.61 +/- 0.14, p=0.0017) when compared with the normal dogs (0.17 +/- 0.10). In addition, the RV Tei index in dogs with TR significantly increased in association with pulmonary hypertension [PH(-), 0.19 +/- 0.09; PH(+), 0.65 +/- 0.14; respectively p<0.0001]. Our study has demonstrated that RV Tei index is a feasible approach to estimate RV function in dogs and is not influenced by heart rate, body weight, and aging. Further investigations are required to clarify the clinical significance of RV Tei index in dogs with right-sided cardiac diseases.

Facile fabrication of eco-friendly nano-mosquitocides: Biophysical characterization and effectiveness on neglected tropical mosquito vectors.

PubMed

Govindarajan, Marimuthu; Hoti, S L; Benelli, Giovanni

2016-12-01

Mosquito (Diptera: Culicidae) vectors are solely responsible for transmitting important diseases such as malaria, dengue, chikungunya, Japanese encephalitis, lymphatic filariasis and Zika virus. Eco-friendly control tools of Culicidae vectors are a priority. In this study, we proposed a facile fabrication process of poly-disperse and stable silver nanoparticles (Ag NPs) using a cheap leaf extract of Ichnocarpus frutescens (Apocyanaceae). Bio-reduced Ag NPs were characterized by UV-vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The acute toxicity of I. frutescens leaf extract and green-synthesized Ag NPs was evaluated against larvae of the malaria vector Anopheles subpictus, the dengue vector Aedes albopictus and the Japanese encephalitis vector Culex tritaeniorhynchus. Compared to the leaf aqueous extract, Ag NPs showed higher toxicity against A. subpictus, A. albopictus, and C. tritaeniorhynchus with LC 50 values of 14.22, 15.84 and 17.26μg/mL, respectively. Ag NPs were found safer to non-target mosquito predators Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC 50 values ranging from 636.61 to 2098.61μg/mL. Overall, this research firstly shed light on the mosquitocidal potential of I. frutescens, a potential bio-resource for rapid, cheap and effective synthesis of poly-disperse and highly stable silver nanocrystals. Copyright © 2016 Elsevier Inc. All rights reserved.

Quantitative analyses and modelling to support achievement of the 2020 goals for nine neglected tropical diseases.

PubMed

Hollingsworth, T Déirdre; Adams, Emily R; Anderson, Roy M; Atkins, Katherine; Bartsch, Sarah; Basáñez, María-Gloria; Behrend, Matthew; Blok, David J; Chapman, Lloyd A C; Coffeng, Luc; Courtenay, Orin; Crump, Ron E; de Vlas, Sake J; Dobson, Andy; Dyson, Louise; Farkas, Hajnal; Galvani, Alison P; Gambhir, Manoj; Gurarie, David; Irvine, Michael A; Jervis, Sarah; Keeling, Matt J; Kelly-Hope, Louise; King, Charles; Lee, Bruce Y; Le Rutte, Epke A; Lietman, Thomas M; Ndeffo-Mbah, Martial; Medley, Graham F; Michael, Edwin; Pandey, Abhishek; Peterson, Jennifer K; Pinsent, Amy; Porco, Travis C; Richardus, Jan Hendrik; Reimer, Lisa; Rock, Kat S; Singh, Brajendra K; Stolk, Wilma; Swaminathan, Subramanian; Torr, Steve J; Townsend, Jeffrey; Truscott, James; Walker, Martin; Zoueva, Alexandra

2015-12-09

Quantitative analysis and mathematical models are useful tools in informing strategies to control or eliminate disease. Currently, there is an urgent need to develop these tools to inform policy to achieve the 2020 goals for neglected tropical diseases (NTDs). In this paper we give an overview of a collection of novel model-based analyses which aim to address key questions on the dynamics of transmission and control of nine NTDs: Chagas disease, visceral leishmaniasis, human African trypanosomiasis, leprosy, soil-transmitted helminths, schistosomiasis, lymphatic filariasis, onchocerciasis and trachoma. Several common themes resonate throughout these analyses, including: the importance of epidemiological setting on the success of interventions; targeting groups who are at highest risk of infection or re-infection; and reaching populations who are not accessing interventions and may act as a reservoir for infection,. The results also highlight the challenge of maintaining elimination 'as a public health problem' when true elimination is not reached. The models elucidate the factors that may be contributing most to persistence of disease and discuss the requirements for eventually achieving true elimination, if that is possible. Overall this collection presents new analyses to inform current control initiatives. These papers form a base from which further development of the models and more rigorous validation against a variety of datasets can help to give more detailed advice. At the moment, the models' predictions are being considered as the world prepares for a final push towards control or elimination of neglected tropical diseases by 2020.

Expression, purification and enzymatic characterization of Brugia malayi dihydrofolate reductase.

PubMed

Perez-Abraham, Romy; Sanchez, Karla Garabiles; Alfonso, Melany; Gubler, Ueli; Siekierka, John J; Goodey, Nina M

2016-12-01

Brugia malayi (B. malayi) is one of the three causative agents of lymphatic filariasis, a neglected parasitic disease. Current literature suggests that dihydrofolate reductase is a potential drug target for the elimination of B. malayi. Here we report the recombinant expression and purification of a ∼20 kDa B. malayi dihydrofolate reductase (BmDHFR). A His6-tagged construct was expressed in E. coli and purified by affinity chromatography to yield active and homogeneous enzyme for steady-state kinetic characterization and inhibition studies. The catalytic activity kcat was found to be 1.4 ± 0.1 s(-1), the Michaelis Menten constant KM for dihydrofolate 14.7 ± 3.6 μM, and the equilibrium dissociation constant KD for NADPH 25 ± 24 nM. For BmDHFR, IC50 values for a six DHFR inhibitors were determined to be 3.1 ± 0.2 nM for methotrexate, 32 ± 22 μM for trimethoprim, 109 ± 34 μM for pyrimethamine, 154 ± 46 μM for 2,4-diaminoquinazoline, 771 ± 44 μM for cycloguanil, and >20,000 μM for 2,4-diaminopyrimidine. Our findings suggest that antifolate compounds can serve as inhibitors of BmDHFR. Copyright © 2016 Elsevier Inc. All rights reserved.

Barrier screens: a method to sample blood-fed and host-seeking exophilic mosquitoes

PubMed Central

2013-01-01

Background Determining the proportion of blood meals on humans by outdoor-feeding and resting mosquitoes is challenging. This is largely due to the difficulty of finding an adequate and unbiased sample of resting, engorged mosquitoes to enable the identification of host blood meal sources. This is particularly difficult in the south-west Pacific countries of Indonesia, the Solomon Islands and Papua New Guinea where thick vegetation constitutes the primary resting sites for the exophilic mosquitoes that are the primary malaria and filariasis vectors. Methods Barrier screens of shade-cloth netting attached to bamboo poles were constructed between villages and likely areas where mosquitoes might seek blood meals or rest. Flying mosquitoes, obstructed by the barrier screens, would temporarily stop and could then be captured by aspiration at hourly intervals throughout the night. Results In the three countries where this method was evaluated, blood-fed females of Anopheles farauti, Anopheles bancroftii, Anopheles longirostris, Anopheles sundaicus, Anopheles vagus, Anopheles kochi, Anopheles annularis, Anopheles tessellatus, Culex vishnui, Culex quinquefasciatus and Mansonia spp were collected while resting on the barrier screens. In addition, female Anopheles punctulatus and Armigeres spp as well as male An. farauti, Cx. vishnui, Cx. quinquefasciatus and Aedes species were similarly captured. Conclusions Building barrier screens as temporary resting sites in areas where mosquitoes were likely to fly was an extremely time-effective method for collecting an unbiased representative sample of engorged mosquitoes for determining the human blood index. PMID:23379959

Larvicidal and repellent activity of the essential oil of Coriandrum sativum L. (Apiaceae) fruits against the filariasis vector Aedes albopictus Skuse (Diptera: Culicidae).

PubMed

Benelli, Giovanni; Flamini, Guido; Fiore, Giulia; Cioni, Pier Luigi; Conti, Barbara

2013-03-01

The essential oils of many Apiaceae species have been already studied for their insecticidal and repellent properties against insect pests. In this research, the essential oil (EO) extracted from the fruits of Coriandrum sativum L. (Apiaceae) was evaluated for the first time for its larvicidal and repellent activities against the most invasive mosquito worldwide, Aedes albopictus Skuse (Diptera: Culicidae). The chemical composition of C. sativum EO was investigated by gas chromatography with electron impact mass spectrometry analysis. Coriander EO was mainly composed by monoterpene hydrocarbons and oxygenated monoterpenes, with linalool (83.6 %) as the major constituent. C. sativum EO exerted toxic activity against A. albopictus larvae: LC(50) was 421 ppm, while LC(90) was 531.7 ppm. Repellence trials highlighted that C. sativum EO was a good repellent against A. albopictus, also at lower dosages: RD(50) was 0.0001565 μL/cm(2) of skin, while RD(90) was 0.002004 μL/cm(2). At the highest dosage (0.2 μL/cm(2) of skin), the protection time achieved with C. sativum essential oil was higher than 60 min. This study adds knowledge about the chemical composition of C. sativum EO as well as to the larvicidal and repellent activity exerted by this EO against A. albopictus. On this basis, we believe that our findings could be useful for the development of new and safer products against the Asian tiger mosquito.

Larvicidal and ovideterrent properties of neem oil and fractions against the filariasis vector Aedes albopictus (Diptera: Culicidae): a bioactivity survey across production sites.

PubMed

Benelli, Giovanni; Bedini, Stefano; Cosci, Francesca; Toniolo, Chiara; Conti, Barbara; Nicoletti, Marcello

2015-01-01

Neem seed oil (NSO) of Azadirachta indica (Meliaceae) contains more than 100 determined biologically active compounds, and many formulations deriving from them showed toxicity, antifeedancy and repellence against a number of arthropod pests. However, it is widely known that botanical products can differ in their chemical composition and bioactivity, as function of the production site and production process. We used high-performance thin layer chromatography (HPTLC) to investigate differences in chemical constituents of NSOs from three production sites. HPTLC analyses showed several differences in chemical abundance and diversity among NSOs, with special reference to limonoids. Furthermore, the three NSOs and their fractions of increasing polarities [i.e. ethyl acetate (EA) fraction and butanol (BU) fraction] were evaluated for larvicidal toxicity and field oviposition deterrence against the Asian tiger mosquito, Aedes albopictus, currently the most invasive mosquito worldwide. Results from bioactivity experiments showed good toxicity of NSOs and EA fractions against A. albopictus fourth instar larvae (with LC50 values ranging from 142.28 to 209.73 ppm), while little toxicity was exerted by BU fractions. A significant effect of the production site and dosage was also found and is probably linked to differences in abundance of constituents among samples, as highlighted by HPTLC analyses. NSOs and EAs were also able to deter A. albopictus oviposition in the field (effective repellence values ranging from 98.55 to 70.10%), while little effectiveness of BU fractions was found. Concerning ovideterrent activity, no difference due to the production site was found. This is the first report concerning larvicidal toxicity of NSO against A. albopictus and ovideterrence against Culicidae in the field. The chance to use chemicals from the NSO EA fraction seems promising, since they are effective at lower doses, if compared to synthetic products currently marketed, and could be an advantageous alternative to build newer and safer mosquito control tools.

[Contribution of palaeopathology to defining the pathocoenosis of infectious diseases (Part two)].

PubMed

Sabbatani, S; Fiorino, S

2009-03-01

In the second part of their review the authors focus on palaeopathological studies, performed in mummified tissues, with reference to infectious diseases. The analysis of samples obtained from both natural and artificial mummies may provide, in some favourable events, a more complete knowledge of these findings in comparison to information obtained from only comprehensive examination of the skeleton. The acquired data enable us to understand not only the diseases which afflicted mankind, but also dietary and hygiene conditions of ancient populations. We report knowledge acquired regarding some palaeopathological conditions, including schistosomiasis, smallpox, cisticercosis, trichinosis, ascaridiasis, echinococcosis, filariasis, hepatitis E virus, condylomatosis, pulmonary tubercolosis, pediculosis, visceral leishmaniasis as well as Diphyllobotrium sp., Dicrocoelium dendriticum and Fasciola hepatica infestations. In addition some interesting findings concerning the relationship between dietary and food intake colonized by streptomyces are described. This review reports the discovery of human remains from different geographic areas: while most of these studies describe findings in two Mediterranean countries (Italy and Egypt), some refer to Britain and German-speaking countries (Austria and Germany) as well as the area in Africa known as Nubia, along the Nile. Both histological and biomolecular diagnosis are useful not only to identify a specific disease in a subject from the remote past, but also to achieve information concerning its frequency and evolution. Such knowledge may thus allow us to understand the intensity of cultural exchanges and links among different populations and the role of these relationships in transmitting and spreading infectious diseases in a certain geographic area.

Vulval elephantiasis as a result of tubercular lymphadenitis: two case reports and a review of the literature

PubMed Central

2010-01-01

Introduction Elephantiasis as a result of chronic lymphedema is characterized by gross enlargement of the arms, legs or genitalia, and occurs due to a variety of obstructive diseases of the lymphatic system. Genital elephantiasis usually follows common filariasis and lymphogranuloma venereum. It may follow granuloma inguinale, carcinomas, lymph node dissection or irradiation and tuberculosis but this happens rarely. Vulval elephantiasis as a consequence of extensive lymph node destruction by tuberculosis is very rare. We present two very unusual cases of vulval elephantiasis due to tuberculous destruction of the inguinal lymph nodes. Case presentation Two Indian women - one aged 40 years and the other aged 27 years, with progressively increasing vulval swellings over a period of five and four years respectively - presented to our hospital. In both cases, there was a significant history on presentation. Both women had previously taken a complete course of anti-tubercular treatment for generalized lymphadenopathy. The vulval swellings were extremely large: in the first case report, measuring 35 × 25 cm on the right side and 45 × 30 cm on the left side, weighing 20 lb and 16 lb respectively. Both cases were managed by surgical excision with reconstruction and the outcome was positive. Satisfactory results have been maintained during a follow-up period of six years in both cases. Conclusions Elephantiasis of the female genitalia is unusual and it has rarely been reported following tuberculosis. We report two cases of vulval elephantiasis as a consequence of extensive lymph node destruction by tuberculosis, in order to highlight this very rare clinical scenario. PMID:21092075

Prevalence of soil transmitted nematodes on Nukufetau, a remote Pacific island in Tuvalu

PubMed Central

Speare, Rick; Latasi, Falatea Fab; Nelesone, Tekaai; Harmen, Sonia; Melrose, Wayne; Durrheim, David; Heukelbach, Jorg

2006-01-01

Background The population of Nukufetau, a remote coral atoll island in Tuvalu in the Western Pacific, received annual mass drug administration (MDA) of diethylcarbamazine and albendazole under the Pacific Elimination of Lymphatic Filariasis program in 2001, 2002 and 2003, with the last MDA occurring six months before a cross-sectional survey of the whole population for soil transmitted helminths (STH). Methods A cross-sectional survey in May 2004 recruited 206 residents (35.2% of the population) who provided a single faecal sample that was preserved, concentrated and examined microscopically. Results Overall prevalence of STH was 69.9%; only hookworm and Trichuris trichiura were diagnosed. Trichuris was present in 68.4% with intensity of infection being light in 56.3%, medium in 11.7% and heavy in 0.5%. Hookworm occurred in 11.7% with intensity of infection 11.2% being light and medium in 0.5%. Twenty individuals (9.7%) had dual infections. The prevalence of Trichuris was constant across all ages while the prevalence of hookworm was significantly lower in residents below 30 years of age. In the age group 5–12 years comparison of results with a 2001 survey [1] suggested that the prevalence of STH has declined minimally, due to sustained high prevalence of Trichuris, while hookworm has declined dramatically from 34.4% to 1.6%. Conclusion The results of this survey suggest that although the MDA appears to have reduced hookworm prevalence in residents below 30 years of age, there has been minimal effect on Trichuris prevalence. An integrated program to control STH is required. PMID:16836746

Nanopharmaceuticals to target antifilarials: a comprehensive review.

PubMed

Ali, Mohammad; Afzal, Mohammad; Bhattacharya, Shailja Misra; Ahmad, Farhan Jalees; Dinda, Amit Kumar

2013-05-01

Currently emphasized conventional chemotherapies for the elimination of lymphatic filariasis (LF) are imperfect due to unfocused targeting of poorly water-soluble antifilarial drugs. The profound location of drug targets (filarial parasites or wolbachia) within the complex anatomy of lymphatic tissues often necessitates prolonged treatment schedules with high doses leading to undesired side effects and poor patient compliance. Therefore, we need to reformulate antifilarial drugs taking the advantages of nanotechnology through a wide range of nanomedical carriers, which improve drug efficacy, increase bioavailability, and diminish toxicity. Connotations of drug delivery systems (DDSs) to target lymphatic filaroids or wolbachia and systemic microfilaria have been discussed. The potentials of liposomes and solid lipid nanoparticles for the treatment of LF are highlighted. Various critical factors, viz optimal size range, surface properties, preferred pH, mechanism of reticuloendothelial avoidance, and control of the release of antifilarial agents for safe elimination of parasites, are enclosed to design a novel DDS for LF. The review of nanotechnological approaches to improve antifilarial chemotherapy will help to resolve existing technological gaps. Precincts in the antifilarial discovery programs can never be overcome by conventional methods. Nanomedicine encompasses wide-range solution for each single problem (i.e., from poor solubility to nonspecific targeting of antifilarial agents) for the cure of LF at low costs and may reduce the economic burden of LF diseases. Advances in nanotechnology loom will certainly come forward as silver bullets in the near future for quick diagnosis, control, and elimination of this tropically neglected disease.

Expatriates ill after travel: Results from the Geosentinel Surveillance Network

PubMed Central

2012-01-01

Background Expatriates are a distinct population at unique risk for health problems related to their travel exposure. Methods We analyzed GeoSentinel data comparing ill returned expatriates with other travelers for demographics, travel characteristics, and proportionate morbidity (PM) for travel-related illness. Results Our study included 2,883 expatriates and 11,910 non-expatriates who visited GeoSentinel clinics ill after travel. Expatriates were more likely to be male, do volunteer work, be long-stay travelers (>6 months), and have sought pre-travel advice. Compared to non-expatriates, expatriates returning from Africa had higher proportionate morbidity (PM) for malaria, filariasis, schistosomiasis, and hepatitis E; expatriates from the Asia-Pacific region had higher PM for strongyloidiasis, depression, and anxiety; expatriates returning from Latin America had higher PM for mononucleosis and ingestion-related infections (giardiasis, brucellosis). Expatriates returning from all three regions had higher PM for latent TB, amebiasis, and gastrointestinal infections (other than acute diarrhea) compared to non-expatriates. When the data were stratified by travel reason, business expatriates had higher PM for febrile systemic illness (malaria and dengue) and vaccine-preventable infections (hepatitis A), and volunteer expatriates had higher PM for parasitic infections. Expatriates overall had higher adjusted odds ratios for latent TB and lower odds ratios for acute diarrhea and dermatologic illness. Conclusions Ill returned expatriates differ from other travelers in travel characteristics and proportionate morbidity for specific diseases, based on the region of exposure and travel reason. They are more likely to present with more serious illness. PMID:23273048

Exome and Transcriptome Sequencing of Aedes aegypti Identifies a Locus That Confers Resistance to Brugia malayi and Alters the Immune Response

PubMed Central

Juneja, Punita; Ariani, Cristina V.; Ho, Yung Shwen; Akorli, Jewelna; Palmer, William J.; Pain, Arnab; Jiggins, Francis M.

2015-01-01

Many mosquito species are naturally polymorphic for their abilities to transmit parasites, a feature which is of great interest for controlling vector-borne disease. Aedes aegypti, the primary vector of dengue and yellow fever and a laboratory model for studying lymphatic filariasis, is genetically variable for its capacity to harbor the filarial nematode Brugia malayi. The genome of Ae. aegypti is large and repetitive, making genome resequencing difficult and expensive. We designed exome captures to target protein-coding regions of the genome, and used association mapping in a wild Kenyan population to identify a single, dominant, sex-linked locus underlying resistance. This falls in a region of the genome where a resistance locus was previously mapped in a line established in 1936, suggesting that this polymorphism has been maintained in the wild for the at least 80 years. We then crossed resistant and susceptible mosquitoes to place both alleles of the gene into a common genetic background, and used RNA-seq to measure the effect of this locus on gene expression. We found evidence for Toll, IMD, and JAK-STAT pathway activity in response to early stages of B. malayi infection when the parasites are beginning to die in the resistant genotype. We also found that resistant mosquitoes express anti-microbial peptides at the time of parasite-killing, and that this expression is suppressed in susceptible mosquitoes. Together, we have found that a single resistance locus leads to a higher immune response in resistant mosquitoes, and we identify genes in this region that may be responsible for this trait. PMID:25815506

Integrated Rapid Mapping of Neglected Tropical Diseases in Three States of South Sudan: Survey Findings and Treatment Needs

PubMed Central

Finn, Timothy P.; Stewart, Barclay T.; Reid, Heidi L.; Petty, Nora; Sabasio, Anthony; Oguttu, David; Lado, Mounir; Brooker, Simon J.; Kolaczinski, Jan H.

2012-01-01

Background Integrated rapid mapping to target interventions for schistosomiasis, soil-transmitted helminthiasis (STH) and lymphatic filariasis (LF) is ongoing in South Sudan. From May to September 2010, three states – Unity, Eastern Equatoria and Central Equatoria – were surveyed with the aim of identifying which administrative areas are eligible for mass drug administration (MDA) of preventive chemotherapy (PCT). Methods and Principal Findings Payams (third administrative tier) were surveyed for Schistosoma mansoni, S. haematobium and STH infections while counties (second administrative tier) were surveyed for LF. Overall, 12,742 children from 193 sites were tested for schistosome and STH infection and, at a subset of 50 sites, 3,980 adults were tested for LF. Either S. mansoni or S. haematobium or both species were endemic throughout Unity State and occurred in foci in Central and Eastern Equatoria. STH infection was endemic throughout Central Equatoria and the western counties of Eastern Equatoria, while LF was endemic over most of Central- and Eastern Equatoria, but only in selected foci in Unity. All areas identified as STH endemic were co-endemic for schistosomiasis and/or LF. Conclusions The distribution and prevalence of major NTDs, particularly schistosomiasis, varies considerably throughout South Sudan. Rapid mapping is therefore important in identifying (co)-endemic areas. The present survey established that across the three surveyed states between 1.2 and 1.4 million individuals are estimated to be eligible for regular MDA with PCT to treat STH and schistosomiasis, respectively, while approximately 1.3 million individuals residing in Central- and Eastern Equatoria are estimated to require MDA for LF. PMID:23285184

A push-pull system to reduce house entry of malaria mosquitoes

PubMed Central

2014-01-01

Background Mosquitoes are the dominant vectors of pathogens that cause infectious diseases such as malaria, dengue, yellow fever and filariasis. Current vector control strategies often rely on the use of pyrethroids against which mosquitoes are increasingly developing resistance. Here, a push-pull system is presented, that operates by the simultaneous use of repellent and attractive volatile odorants. Method/Results Experiments were carried out in a semi-field set-up: a traditional house which was constructed inside a screenhouse. The release of different repellent compounds, para-menthane-3,8-diol (PMD), catnip oil e.o. and delta-undecalactone, from the four corners of the house resulted in significant reductions of 45% to 81.5% in house entry of host-seeking malaria mosquitoes. The highest reductions in house entry (up to 95.5%), were achieved by simultaneously repelling mosquitoes from the house (push) and removing them from the experimental set-up using attractant-baited traps (pull). Conclusions The outcome of this study suggests that a push-pull system based on attractive and repellent volatiles may successfully be employed to target mosquito vectors of human disease. Reductions in house entry of malaria vectors, of the magnitude that was achieved in these experiments, would likely affect malaria transmission. The repellents used are non-toxic and can be used safely in a human environment. Delta-undecalactone is a novel repellent that showed higher effectiveness than the established repellent PMD. These results encourage further development of the system for practical implementation in the field. PMID:24674451

Mosquitoes established in Lhasa city, Tibet, China

PubMed Central

2013-01-01

Background In 2009, residents of Lhasa city, Tibet Autonomous Region (TAR), China reported large numbers of mosquitoes and bites from these insects. It is unclear whether this was a new phenomenon, which species were involved, and whether these mosquitoes had established themselves in the local circumstances. Methods The present study was undertaken in six urban sites of Chengguan district Lhasa city, Tibet. Adult mosquitoes were collected by bed net trap, labor hour method and light trap in August 2009 and August 2012. The trapped adult mosquitoes were initially counted and identified according to morphological criteria, and a proportion of mosquitoes were examined more closely using a multiplex PCR assay. Results 907 mosquitoes of the Culex pipiens complex were collected in this study. Among them, 595 were females and 312 were males. There was no significant difference in mosquito density monitored by bed net trap and labor hour method in 2009 and 2012. Of 105 mosquitoes identified by multiplex PCR, 36 were pure mosquitoes (34.29%) while 69 were hybrids (65.71%). The same subspecies of Culex pipiens complex were observed by bed net trap, labor hour method and light trap in 2009 and 2012. Conclusion The local Culex pipiens complex comprises the subspecies Cx. pipiens pipiens, Cx. pipiens pallens, Cx. pipiens quinquefasciatus and its hybrids. Mosquitoes in the Cx. pipiens complex, known to be, potentially, vectors of periodic filariasis and encephalitis, are now present from one season to the next, and appear to be established in Lhasa City, TAR. PMID:24060238

Fine needle aspiration cytology in lesions of the nose, nasal cavity and paranasal sinuses.

PubMed

Gupta, Nalini; Kaur, Jasleen; Srinivasan, Radhika; Das, Ashim; Mohindra, Satyawati; Rajwanshi, Arvind; Nijhawan, Raje

2011-01-01

To assess the spectrum of lesions in the sinonasal region diagnosed on FNAC. This is a retrospective audit of sinonasal lesions diagnosed on FNAC over a period of 12 years (1998-2009). Out of a total of 79,851 FNACs, 158 (0.2%) were from the sinonasal region. FNAC was non-diagnostic in 20 (12.6%) cases. Infective/inflammatory lesions comprised of 30 (19%) cases including non-specific inflammation (19), fungal infection (7), tuberculosis (2), actinomycosis (1) and filariasis (1). Benign cysts (24; 15.2%) included epidermal inclusion cysts, mucocele and aneurysmal bone cyst. Benign bone tumors (4) comprised of giant cell tumor, fibrous dysplasia, chondroma, and osteoblastoma. Other benign tumors included lipoma (6), hemangioma (5), schwannoma (2), meningioma (1), pleomorphic adenoma (1), sebaceous adenoma (1) and other skin adnexal tumors (3). Malignant epithelial tumors (24; 15.2%) included squamous cell carcinoma (10), basal cell carcinoma (5), poorly differentiated carcinoma (4) and metastatic carcinoma (5). Two cases of chordoma and one case each of dermatofibrosarcoma pertuberance and hemangiopericytoma were seen. Sarcomas included sarcoma, not otherwise specified (4), rhabdomyosarcoma (3), osteosarcoma (2), chondrosarcoma (2), leiomyosarcoma (1), malignant fibrous histiocytoma (1), fibrosarcoma (1) and malignant peripheral nerve sheath tumor (1). There were cases of malignant small round cell tumor (11), non-Hodgkin lymphoma (3), plasmacytoma (2) and malignant melanoma (2). A variety of non-neoplastic and neoplastic conditions can involve the sinonasal region. FNAC is a reliable diagnostic procedure in a good number of cases, especially in the light of clinico-radiological data. Copyright © 2011 S. Karger AG, Basel.

More than one rabbit out of the hat: Radiation, transgenic and symbiont-based approaches for sustainable management of mosquito and tsetse fly populations.

PubMed

Bourtzis, Kostas; Lees, Rosemary Susan; Hendrichs, Jorge; Vreysen, Marc J B

2016-05-01

Mosquitoes (Diptera: Culicidae) and tsetse flies (Diptera: Glossinidae) are bloodsucking vectors of human and animal pathogens. Mosquito-borne diseases (malaria, filariasis, dengue, zika, and chikungunya) cause severe mortality and morbidity annually, and tsetse fly-borne diseases (African trypanosomes causing sleeping sickness in humans and nagana in livestock) cost Sub-Saharan Africa an estimated US$ 4750 million annually. Current reliance on insecticides for vector control is unsustainable: due to increasing insecticide resistance and growing concerns about health and environmental impacts of chemical control there is a growing need for novel, effective and safe biologically-based methods that are more sustainable. The integration of the sterile insect technique has proven successful to manage crop pests and disease vectors, particularly tsetse flies, and is likely to prove effective against mosquito vectors, particularly once sex-separation methods are improved. Transgenic and symbiont-based approaches are in development, and more advanced in (particularly Aedes) mosquitoes than in tsetse flies; however, issues around stability, sustainability and biosecurity have to be addressed, especially when considering population replacement approaches. Regulatory issues and those relating to intellectual property and economic cost of application must also be overcome. Standardised methods to assess insect quality are required to compare and predict efficacy of the different approaches. Different combinations of these three approaches could be integrated to maximise their benefits, and all have the potential to be used in tsetse and mosquito area-wide integrated pest management programmes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Current status of genome editing in vector mosquitoes: A review.

PubMed

Reegan, Appadurai Daniel; Ceasar, Stanislaus Antony; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu; Al-Dhabi, Naif Abdullah

2017-01-16

Mosquitoes pose a major threat to human health as they spread many deadly diseases like malaria, dengue, chikungunya, filariasis, Japanese encephalitis and Zika. Identification and use of novel molecular tools are essential to combat the spread of vector borne diseases. Genome editing tools have been used for the precise alterations of the gene of interest for producing the desirable trait in mosquitoes. Deletion of functional genes or insertion of toxic genes in vector mosquitoes will produce either knock-out or knock-in mutants that will check the spread of vector-borne diseases. Presently, three types of genome editing tools viz., zinc finger nuclease (ZFN), transcription activator-like effector nucleases (TALEN) and clustered regulatory interspaced short palindromic repeats (CRISPR) and CRISPR associated protein 9 (Cas9) are widely used for the editing of the genomes of diverse organisms. These tools are also applied in vector mosquitoes to control the spread of vector-borne diseases. A few studies have been carried out on genome editing to control the diseases spread by vector mosquitoes and more studies need to be performed with the utilization of more recently invented tools like CRISPR/Cas9 to combat the spread of deadly diseases by vector mosquitoes. The high specificity and flexibility of CRISPR/Cas9 system may offer possibilities for novel genome editing for the control of important diseases spread by vector mosquitoes. In this review, we present the current status of genome editing research on vector mosquitoes and also discuss the future applications of vector mosquito genome editing to control the spread of vectorborne diseases.

Integration of mass drug administration programmes in Nigeria: The challenge of schistosomiasis.

PubMed Central

Richards, Frank O.; Eigege, Abel; Miri, Emmanuel S.; Jinadu, M. Y.; Hopkins, Donald R.

2006-01-01

PROBLEM: Annual mass drug administration (MDA) with safe oral anthelminthic drugs (praziquantel, ivermectin and albendazole) is the strategy for control of onchocerciasis, lymphatic filariasis (LF) and schistosomiasis. District health officers seek to integrate treatment activities in areas of overlapping disease endemicity, but they are faced with having to merge different programmatic guidelines. APPROACH: We proceeded through the three stages of integrated MDA implementation: mapping the distribution of the three diseases at district level; tailoring district training and logistics based on the results of the mapping exercises; and implementing community-based annual health education and mass treatment where appropriate. During the process we identified the "know-do" gaps in the MDA guidelines for each disease that prevented successful integration of these programmes. LOCAL SETTING: An integrated programme launched in 1999 in Plateau and Nasarawa States in central Nigeria, where all three diseases were known to occur. RELEVANT CHANGES: Current guidelines allowed onchocerciasis and LF activities to be integrated, resulting in rapid mapping throughout the two states, and states-wide provision of over 9.3 million combined ivermectin-albendazole treatments for the two diseases between 2000 and 2004. In contrast, schistosomiasis activities could not be effectively integrated because of the more restrictive guidelines, resulting in less than half of the two states being mapped, and delivery of only 701,419 praziquantel treatments for schistosomiasis since 1999. LESSONS LEARNED: Integration of schistosomiasis into other MDA programmes would be helped by amended guidelines leading to simpler mapping, more liberal use of praziquantel and the ability to administer praziquantel simultaneously with ivermectin and albendazole. PMID:16917658

Monitoring the efficacy of drugs for neglected tropical diseases controlled by preventive chemotherapy

PubMed Central

Albonico, M.; Levecke, B.; LoVerde, P.T.; Montresor, A.; Prichard, R.; Vercruysse, J.; Webster, J.P.

2017-01-01

In the last decade, pharmaceutical companies, governments and global health organisations under the leadership of the World Health Organization (WHO) have pledged large-scale donations of anthelmintic drugs, including ivermectin (IVM), praziquantel (PZQ), albendazole (ALB) and mebendazole (MEB). This worldwide scale-up in drug donations calls for strong monitoring systems to detect any changes in anthelmintic drug efficacy. This review reports on the outcome of the WHO Global Working Group on Monitoring of Neglected Tropical Diseases Drug Efficacy, which consists of three subgroups: (i) soil-transmitted helminthiases (ALB and MEB); (ii) onchocerciasis and lymphatic filariasis (IVM); and (iii) schistosomiasis (PZQ). Progress of ongoing work, challenges and research needs for each of the four main drugs used in helminthic preventive chemotherapy (PC) are reported, laying the ground for appropriate implementation of drug efficacy monitoring programmes under the co-ordination and guidelines of the WHO. Best practices for monitoring drug efficacy should be made available and capacity built as an integral part of neglected tropical disease (NTD) programme monitoring. Development of a disease-specific model to predict the impact of PC programmes, to detect outliers and to solicit responses is essential. Research studies on genetic polymorphisms in relation to low-efficacy phenotypes should be carried out to identify markers of putative resistance against all NTD drugs and ultimately to develop diagnostic assays. Development of combination and co-administration of NTD drugs as well as of new drug entities to boost the armamentarium of the few drugs available for NTD control and elimination should be pursued in parallel. PMID:27842865

Agricultural chemicals: life changer for mosquito vectors in agricultural landscapes?

PubMed

Kibuthu, Tabitha W; Njenga, Sammy M; Mbugua, Amos K; Muturi, Ephantus J

2016-09-13

Although many mosquito species develop within agricultural landscapes where they are potentially exposed to agricultural chemicals (fertilizers and pesticides), the effects of these chemicals on mosquito biology remain poorly understood. This study investigated the effects of sublethal concentrations of four agricultural chemicals on the life history traits of Anopheles arabiensis and Culex quinquefasciatus mosquitoes. Field and laboratory experiments were conducted to examine how sublethal concentrations of four agricultural chemicals: an insecticide (cypermethrin), a herbicide (glyphosate), and two nitrogenous fertilizers (ammonium sulfate and diammonium phosphate) alter oviposition site selection, emergence rates, development time, adult body size, and longevity of An. arabiensis and Cx. quinquefasciatus. Both mosquito species had preference to oviposit in fertilizer treatments relative to pesticide treatments. Emergence rates for An. arabiensis were significantly higher in the control and ammonium sulfate treatments compared to cypermethrin treatment, while emergence rates for Cx. quinquefasciatus were significantly higher in the diammonium phosphate treatment compared to glyphosate and cypermethrin treatments. For both mosquito species, individuals from the ammonium sulfate and diammonium phosphate treatments took significantly longer time to develop compared to those from cypermethrin and glyphosate treatments. Although not always significant, males and females of both mosquito species tended to be smaller in the ammonium sulfate and diammonium phosphate treatments compared to cypermethrin and glyphosate treatments. There was no significant effect of the agrochemical treatments on the longevity of either mosquito species. These results demonstrate that the widespread use of agricultural chemicals to enhance crop production can have unexpected effects on the spatial distribution and abundance of mosquito vectors of malaria and lymphatic filariasis.

Future Research Priorities for Morbidity Control of Lymphedema.

PubMed

Narahari, S R; Aggithaya, Madhur Guruprasad; Moffatt, Christine; Ryan, T J; Keeley, Vaughan; Vijaya, B; Rajendran, P; Karalam, S B; Rajagopala, S; Kumar, N K; Bose, K S; Sushma, K V

2017-01-01

Innovation in the treatment of lower extremity lymphedema has received low priority from the governments and pharmaceutical industry. Advancing lymphedema is irreversible and initiates fibrosis in the dermis, reactive changes in the epidermis and subcutis. Most medical treatments offered for lymphedema are either too demanding with a less than satisfactory response or patients have low concordance due to complex schedules. A priority setting partnership (PSP) was established to decide on the future priorities in lymphedema research. A table of abstracts following a literature search was published in workshop website. Stake holders were requested to upload their priorities. Their questions were listed, randomized, and sent to lymphologists for ranking. High ranked ten research priorities, obtained through median score, were presented in final prioritization work shop attended by invited stake holders. A free medical camp was organized during workshop to understand patients' priorities. One hundred research priorities were selected from priorities uploaded to website. Ten priorities were short listed through a peer review process involving 12 lymphologists, for final discussion. They were related to simplification of integrative treatment for lymphedema, cellular changes in lymphedema and mechanisms of its reversal, eliminating bacterial entry lesions to reduce cellulitis episodes, exploring evidence for therapies in traditional medicine, improving patient concordance to compression therapy, epidemiology of lymphatic filariasis (LF), and economic benefit of integrative treatments of lymphedema. A robust research priority setting process, organized as described in James Lind Alliance guidebook, identified seven priority areas to achieve effective morbidity control of lymphedema including LF. All stake holders including Department of Health Research, Government of India, participated in the PSP.

New drugs, new vaccines, new diseases. An interview with Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID).

PubMed

Fuller, J

1996-11-01

This document presents an interview with Dr. Anthony Fauci on the development of a new generation of vaccines to prevent and possibly eradicate a legion of deadly diseases ranging from tuberculosis to AIDS. Infections that have caused major devastations in the world today include tuberculosis, malaria, schistosomiasis, filariasis, pneumococcal pneumonia, influenza, AIDS, and Ebola. Agencies should be making sure that the basic research base in microbiology, immunology, antimicrobials, and vaccinology is at the very highest level. The integration of research efforts between countries depends on collaboration between the investigators of home countries with foreign investigators. Among new developments in vaccinology are an acellular pertussis vaccine for pertussis/whooping cough (an extremely contagious disease that causes death), DNA immunization (a new technique applicable to all types of diseases), and transgenic plants for immunization against hepatitis, pertussis, and polio. As of now, AIDS in Western countries has declined, while in Africa and Asia its spread has accelerated. Combination therapy for AIDS has had a profound impact on the level of the virus in the body; however, the treatment is still vague. The good news with regard to AIDS is that education is having an impact; this is exemplified by the situation in Thailand, where the government together with nongovernmental organizations and the military has begun a crash education campaign regarding prostitutes and the use of condoms. Progress is being made in the search for better vaccine candidates. AIDS-like epidemics involving new diseases are bound to emerge at some future point, though, given the long-term historical trend.

Elimination of Neglected Diseases in Latin America and the Caribbean: A Mapping of Selected Diseases

PubMed Central

Schneider, Maria Cristina; Aguilera, Ximena Paz; Barbosa da Silva Junior, Jarbas; Ault, Steven Kenyon; Najera, Patricia; Martinez, Julio; Requejo, Raquel; Nicholls, Ruben Santiago; Yadon, Zaida; Silva, Juan Carlos; Leanes, Luis Fernando; Periago, Mirta Roses

2011-01-01

In Latin America and the Caribbean, around 195 million people live in poverty, a situation that increases the burden of some infectious diseases. Neglected diseases, in particular, are often restricted to poor, marginalized sections of the population. Tools exist to combat these diseases, making it imperative to work towards their elimination. In 2009, the Pan American Health Organization (PAHO) received a mandate to support the countries in the Region in eliminating neglected diseases and other poverty-related infections. The objective of this study is to analyze the presence of selected diseases using geo-processing techniques. Five diseases with information available at the first sub-national level (states) were mapped, showing the presence of the disease (“hotspots”) and overlap of diseases (“major hotspots”). In the 45 countries/territories (approximately 570 states) of the Region, there is: lymphatic filariasis in four countries (29 states), onchocerciasis in six countries (25 states), schistosomiasis in four countries (39 states), trachoma in three countries (29 states), and human rabies transmitted by dogs in ten countries (20 states). Of the 108 states with one or more of the selected diseases, 36 states present the diseases in overlapping areas (“major hotspots”). Additional information about soil-transmitted helminths was included. The analysis suggests a majority of the selected diseases are not widespread and can be considered part of an unfinished agenda with elimination as a goal. Integrated plans and a comprehensive approach, ensuring access to existing diagnostic and treatment methods, and establishing a multi-sectoral agenda that addresses social determinants, including access to adequate water and sanitation, are required. Future studies can include additional diseases, socio-economic and environmental variables. PMID:21358810

Ethnobotanical knowledge on botanical repellents employed in the African region against mosquito vectors - A review.

PubMed

Pavela, Roman; Benelli, Giovanni

2016-08-01

Mosquitoes (Diptera: Culicidae) represent a huge threat for millions of humans and animals worldwide, since they act as vectors for important parasites and pathogens, including malaria, filariasis and important arboviruses, such as dengue, West Nile and Zika virus. No vaccines or other specific treatments are available against the arboviruses transmitted by mosquitoes, and avoidance of mosquito bites remains the best strategy. African regions are usually hit most whose inhabitants are poor, and the use of repellent plants is the only efficient protection against vectors they have. Ethnobotanical knowledge of such plants and their use is usually passed on orally from one generation to another. However, it is also important to preserve this information in a written form, as well. Ethnobotanical research projects carried out in the regions of today's Ethiopia, South Africa, Nigeria, Kenya, and Tanzania indicate that the native inhabitants of the African study regions traditionally use 64 plant species, belonging to 30 families. Aromatic plants (i.e., Citrus spp., Eucalyptus spp., Lantana camara, Ocimum spp. and Lippia javanica) the most commonly used in all the study regions. Native people know three major methods of using repellent plants: (i) production of repellent smoke from burning plants, (ii) hanging plants inside the house or sprinkling leaves on the floor, (iii) the use of plant oils, juices from crushed fresh parts of the plants, or various prepared extracts applied on uncovered body parts. Overall, this review covers studies conducted only in a limited part of the African continent, highlighting the importance to undertake further research efforts to preserve the unique knowledge and traditions of the native tribes. Copyright © 2016 Elsevier Inc. All rights reserved.

A Research Agenda for Helminth Diseases of Humans: The Problem of Helminthiases

PubMed Central

Lustigman, Sara; Prichard, Roger K.; Gazzinelli, Andrea; Grant, Warwick N.; Boatin, Boakye A.; McCarthy, James S.; Basáñez, María-Gloria

2012-01-01

A disproportionate burden of helminthiases in human populations occurs in marginalised, low-income, and resource-constrained regions of the world, with over 1 billion people in developing areas of sub-Saharan Africa, Asia, and the Americas infected with one or more helminth species. The morbidity caused by such infections imposes a substantial burden of disease, contributing to a vicious circle of infection, poverty, decreased productivity, and inadequate socioeconomic development. Furthermore, helminth infection accentuates the morbidity of malaria and HIV/AIDS, and impairs vaccine efficacy. Polyparasitism is the norm in these populations, and infections tend to be persistent. Hence, there is a great need to reduce morbidity caused by helminth infections. However, major deficiencies exist in diagnostics and interventions, including vector control, drugs, and vaccines. Overcoming these deficiencies is hampered by major gaps in knowledge of helminth biology and transmission dynamics, platforms from which to help develop such tools. The Disease Reference Group on Helminths Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), was given the mandate to review helminthiases research and identify research priorities and gaps. In this review, we provide an overview of the forces driving the persistence of helminthiases as a public health problem despite the many control initiatives that have been put in place; identify the main obstacles that impede progress towards their control and elimination; and discuss recent advances, opportunities, and challenges for the understanding of the biology, epidemiology, and control of these infections. The helminth infections that will be discussed include: onchocerciasis, lymphatic filariasis, soil-transmitted helminthiases, schistosomiasis, food-borne trematodiases, and taeniasis/cysticercosis. PMID:22545164

Integrated Surveys of Neglected Tropical Diseases in Southern Sudan: How Much Do They Cost and Can They Be Refined?

PubMed Central

Kolaczinski, Jan H.; Hanson, Kara; Robinson, Emily; Picon, Diana; Sabasio, Anthony; Mpakateni, Martin; Lado, Mounir; Moore, Stephen; Petty, Nora; Brooker, Simon

2010-01-01

Background Increasing emphasis on integrated control of neglected tropical diseases (NTDs) requires identification of co-endemic areas. Integrated surveys for lymphatic filariasis (LF), schistosomiasis and soil-transmitted helminth (STH) infection have been recommended for this purpose. Integrated survey designs inevitably involve balancing the costs of surveys against accuracy of classifying areas for treatment, so-called implementation units (IUs). This requires an understanding of the main cost drivers and of how operating procedures may affect both cost and accuracy of surveys. Here we report a detailed cost analysis of the first round of integrated NTD surveys in Southern Sudan. Methods and Findings Financial and economic costs were estimated from financial expenditure records and interviews with survey staff using an ingredients approach. The main outcome was cost per IU surveyed. Uncertain variables were subjected to univariate sensitivity analysis and the effects of modifying standard operating procedures were explored. The average economic cost per IU surveyed was USD 40,206 or USD 9,573, depending on the size of the IU. The major cost drivers were two key categories of recurrent costs: i) survey consumables, and ii) personnel. Conclusion The cost of integrated surveys in Southern Sudan could be reduced by surveying larger administrative areas for LF. If this approach was taken, the estimated economic cost of completing LF, schistosomiasis and STH mapping in Southern Sudan would amount to USD 1.6 million. The methodological detail and costing template provided here could be used to generate cost estimates in other settings and readily compare these to the present study, and may help budget for integrated and single NTDs surveys elsewhere. PMID:20644619