Science.gov

Sample records for africa field epidemiology

  1. Public health laboratory systems development in East Africa through training in laboratory management and field epidemiology

    PubMed Central

    Mosha, Fausta; Oundo, Joseph; Mukanga, David; Njenga, Kariuki; Nsubuga, Peter

    2011-01-01

    Laboratories are integral to the delivery of quality health care and for public health functions; however laboratory systems and services are often neglected in resource-poor settings such as the East African region. In order to sustainably strengthen national laboratory systems in resource-poor countries, there is a need to train laboratory personnel to work in clinical as well as public health laboratories. In 2004,Kenya, Uganda, Tanzania, and South Sudan began training public health laboratory workers jointly with field epidemiologists in the Kenya Field Epidemiology and Laboratory Training Program (FELTP), and later through the Tanzania FELTP, as a strategy to strengthen public health laboratories. These programs train laboratory epidemiologists through a two-year public health leadership development course, and also offer various types of short course training for frontline staff. The FELTP laboratory graduates in Kenya, Tanzania, Uganda, and South Sudan are working in their respective countries to strengthen public health laboratory systems while the short course participants provide a pool of frontline implementers with the capacity to support the lower tiers of health systems, as well as serve as surge capacity for the regions and the national level. Through training competent public health laboratory workers, the East African ministries of health, in collaboration with other regional partners and stakeholders are now engaged in developing and implementing a holistic approach that will guarantee an overall strengthening of the health system by using well-trained public health laboratory leaders to drive the process. Strengthening public health laboratory medicine in East Africa is critical to improve health-care systems. The experience with the FELTP model in East Africa is a step in the right direction towards ensuring a stronger role for the laboratory in public health. PMID:22359702

  2. Field Epidemiology and Laboratory Training Programs in West Africa as a model for sustainable partnerships in animal and human health.

    PubMed

    Becker, Karen M; Ohuabunwo, Chima; Ndjakani, Yassa; Nguku, Patrick; Nsubuga, Peter; Mukanga, David; Wurapa, Frederick

    2012-09-01

    The concept of animal and human health experts working together toward a healthier world has been endorsed, but challenges remain in identifying concrete actions to move this one health concept from vision to action. In 2008, as a result of avian influenza outbreaks in West Africa, international donor support led to a unique opportunity to invest in Field Epidemiology and Laboratory Training Programs (FELTPs) in the region that engaged the animal and human health sectors to strengthen the capacity for prevention and control of zoonotic diseases. The FELTPs mixed 25% to 35% classroom and 65% to 75% field-based training and service for cohorts of physicians, veterinarians, and laboratory scientists. They typically consisted of a 2-year course leading to a master's degree in field epidemiology and public health laboratory management for midlevel public health leaders and competency-based short courses for frontline public health surveillance workers. Trainees and graduates work in multidisciplinary teams to conduct surveillance, outbreak investigations, and epidemiological studies for disease control locally and across borders. Critical outcomes of these programs include development of a cadre of public health leaders with core skills in integrated disease surveillance, outbreak investigation, vaccination campaigns, laboratory diagnostic testing, and epidemiological studies that address priority public health problems. A key challenge exists in identifying ways to successfully scale up and transform this innovative donor-driven program into a sustainable multisectoral one health workforce capacity development model. PMID:22916854

  3. Field Epidemiology and Laboratory Training Programs in sub-Saharan Africa from 2004 to 2010: need, the process, and prospects.

    PubMed

    Nsubuga, Peter; Johnson, Kenneth; Tetteh, Christopher; Oundo, Joseph; Weathers, Andrew; Vaughan, James; Elbon, Suzanne; Tshimanga, Mufuta; Ndugulile, Faustine; Ohuabunwo, Chima; Evering-Watley, Michele; Mosha, Fausta; Oleribe, Obinna; Nguku, Patrick; Davis, Lora; Preacely, Nykiconia; Luce, Richard; Antara, Simon; Imara, Hiari; Ndjakani, Yassa; Doyle, Timothy; Espinosa, Yescenia; Kazambu, Ditu; Delissaint, Dieula; Ngulefac, John; Njenga, Kariuki

    2011-01-01

    As of 2010 sub-Saharan Africa had approximately 865 million inhabitants living with numerous public health challenges. Several public health initiatives [e.g., the United States (US) President's Emergency Plan for AIDS Relief and the US President's Malaria Initiative] have been very successful at reducing mortality from priority diseases. A competently trained public health workforce that can operate multi-disease surveillance and response systems is necessary to build upon and sustain these successes and to address other public health problems. Sub-Saharan Africa appears to have weathered the recent global economic downturn remarkably well and its increasing middle class may soon demand stronger public health systems to protect communities. The Epidemic Intelligence Service (EIS) program of the US Centers for Disease Control and Prevention (CDC) has been the backbone of public health surveillance and response in the US during its 60 years of existence. EIS has been adapted internationally to create the Field Epidemiology Training Program (FETP) in several countries. In the 1990s CDC and the Rockefeller Foundation collaborated with the Uganda and Zimbabwe ministries of health and local universities to create 2-year Public Health Schools Without Walls (PHSWOWs) which were based on the FETP model. In 2004 the FETP model was further adapted to create the Field Epidemiology and Laboratory Training Program (FELTP) in Kenya to conduct joint competency-based training for field epidemiologists and public health laboratory scientists providing a master's degree to participants upon completion. The FELTP model has been implemented in several additional countries in sub-Saharan Africa. By the end of 2010 these 10 FELTPs and two PHSWOWs covered 613 million of the 865 million people in sub-Saharan Africa and had enrolled 743 public health professionals. We describe the process that we used to develop 10 FELTPs covering 15 countries in sub-Saharan Africa from 2004 to 2010 as a

  4. [Field epidemiology and social epidemiology].

    PubMed

    Segura del Pozo, Javier

    2006-01-01

    Comparing field epidemiology and social epidemiology, we pretend to think about the no explicit images and meanings operating in both necessary convergent fields, about the obstacles present in epidemiological practice to fulfil its social function and about the necessity of changing epistemological, methodological and practice grounds, beginning with field epidemiologists teaching programmes. Field epidemiology would tend to act in an absent theoretical frame. On the other hand, social epidemiology would tend to prioritize theoretical developments (thinking and research about social determinants) without correspondent action, because of the limits to change public policies. Other differences are found at intervention level (micro-macrospace), its aim (outbreak control vs. inequalities control) and the way to communicate with society. They are similar in the methodological concern, the predominance of orientation based on positivism and framed through statistic methods, but in process of epistemological opening, the stress experienced between the alternative relationship to a virtual world of data bases or to the real society, their peripherical situation in relation of the political, social, institutional and professional system and the tendency to professional frustration. Finally, we ask ten questions to the field epidemiologists related with their present practice, in order to consider if they are developing social epidemiology, and propose some changes in epidemiologist teaching and practice.

  5. Norovirus Epidemiology in Africa: A Review

    PubMed Central

    Mans, Janet; Armah, George E.; Steele, A. Duncan; Taylor, Maureen B.

    2016-01-01

    Norovirus (NoV) is recognised as a leading cause of gastroenteritis worldwide across all age groups. The prevalence and diversity of NoVs in many African countries is still unknown, although early sero-prevalence studies indicated widespread early infection. Reports on NoVs in Africa vary widely in terms of study duration, population groups and size, inclusion of asymptomatic controls, as well as genotyping information. This review provides an estimate of NoV prevalence and distribution of genotypes of NoVs in Africa. Inclusion criteria for the review were study duration of at least 6 months, population size of >50 and diagnosis by RT-PCR. As regions used for genotyping varied, or genotyping was not always performed, this was not considered as an inclusion criteria. A literature search containing the terms norovirus+Africa yielded 74 publications. Of these 19 studies from 14 out of the 54 countries in Africa met the inclusion criteria. Data from studies not meeting the inclusion criteria, based on sample size or short duration, were included as discussion points. The majority of studies published focused on children, under five years of age, hospitalised with acute gastroenteritis. The mean overall prevalence was 13.5% (range 0.8–25.5%) in children with gastroenteritis and 9.7% (range 7–31%) in asymptomatic controls, where tested. NoV GII.4 was the predominant genotype identified in most of the studies that presented genotyping data. Other prevalent genotypes detected included GII.3 and GII.6. In conclusion, NoV is a common pathogen in children with diarrhoea in Africa, with considerable carriage in asymptomatic children. There is however, a paucity of data on NoV infection in adults. PMID:27116615

  6. The epidemiology of tuberculosis in South Africa.

    PubMed

    Donald, P R

    1998-01-01

    Reports by reliable observers indicate that tuberculous disease did not occur to any great extent amongst South Africa's indigenous peoples prior to European colonization. Colonization introduced sources of infection and caused rapid urbanization for purposes of commerce and trade. By the start of the 20th century tuberculosis was recognized as a common health problem amongst the Black and Coloured peoples of South Africa. National notification commenced in 1921 and an incidence of 43 per 100,000 rose to 365 per 100,000 in 1958 and declined to 162 per 100,000 in 1986 before rising again to 221 per 100,000 in 1993. High incidences have been consistently recorded amongst the Coloured population of the Western Cape Province: in 1993 713 per 100,000 compared to the national incidence of 225 per 100,000. Using a computerized geographical information system the precise distribution of tuberculosis in two adjacent underprivileged, mainly Coloured communities, with a combined population of 34,000, is being studied. From 1985 to 1994 4044 notified tuberculosis cases gave an incidence of about 1200 per 100,000, varying from 78 to 3150 per 100,000 for the 39 enumerator subdistricts used for census purposes, and was highest in those with the lowest income. Of 5345 housing units 1835 (34%) housed at least one case of tuberculosis and 483 (9%) three or more cases. IS6110 DNA fingerprinting of strains from this community has shown a high degree of strain diversity (209 out of 334 strains evaluated). Clustering, indicative of recent transmission, was found in only 30% of isolates in this high tuberculosis incidence community. PMID:9949799

  7. Applied field epidemiology programme in Spain.

    PubMed

    Martinez Navarro, J F; Herrera, D; Sanchez Barco, C

    2001-03-01

    In 1994, the Instituto de Salud Carlos III (ISCIII; Carlos III Health Institute) of the Spanish Ministry of Health and the Consumer (MSC) created the Programa de Epidemiología Aplicada de Campo (PEAC; Applied Field Epidemiology Programme). The programme is managed by the Centro Nacional de Epidemiología (National Epidemiological Centre) in collaboration with the Escuela Nacional de Sanidad (National School of Health), and supported by General Direction for Health and Consumer of MSC and the Health Councils (Consejerías de Sanidad) of the autonomous regions. The PEAC runs a masters degree programme in applied field epidemiology, in which degrees are conferred by the National School of Health. As PEAC is a national programme, it forms a part of the European Program for Intervention Epidemiology Training (EPIET) and is a member of the Network Training for Epidemiology Public Health Intervention (TEPHINET), the association of 27 regional and national programmes of the acting Intervention Epidemiology Training Programs.

  8. Common Epidemiology of Rickettsia felis Infection and Malaria, Africa

    PubMed Central

    Mediannikov, Oleg; Socolovschi, Cristina; Edouard, Sophie; Fenollar, Florence; Mouffok, Nadjet; Bassene, Hubert; Diatta, Georges; Tall, Adama; Niangaly, Hamidou; Doumbo, Ogobara; Lekana-Douki, Jean Bernard; Znazen, Abir; Sarih, M’hammed; Ratmanov, Pavel; Richet, Herve; Ndiath, Mamadou O.; Sokhna, Cheikh; Parola, Philippe

    2013-01-01

    This study aimed to compare the epidemiology of Rickettsia felis infection and malaria in France, North Africa, and sub-Saharan Africa and to identify a common vector. Blood specimens from 3,122 febrile patients and from 500 nonfebrile persons were analyzed for R. felis and Plasmodium spp. We observed a significant linear trend (p<0.0001) of increasing risk for R. felis infection. The risks were lowest in France, Tunisia, and Algeria (1%), and highest in rural Senegal (15%). Co-infections with R. felis and Plasmodium spp. and occurrences of R. felis relapses or reinfections were identified. This study demonstrates a correlation between malaria and R. felis infection regarding geographic distribution, seasonality, asymptomatic infections, and a potential vector. R. felis infection should be suspected in these geographical areas where malaria is endemic. Doxycycline chemoprophylaxis against malaria in travelers to sub-Saharan Africa also protects against rickettsioses; thus, empirical treatment strategies for febrile illness for travelers and residents in sub-Saharan Africa may require reevaluation. PMID:24188709

  9. The genesis and evolution of the African Field Epidemiology Network.

    PubMed

    Mukanga, David; Tshimanga, Mufuta; Wurapa, Frederick; Binka, Fred; Serwada, David; Bazeyo, William; Pariyo, George; Wabwire-Mangen, Fred; Gitta, Sheba; Chungong, Stella; Trostle, Murray; Nsubuga, Peter

    2011-01-01

    In an effort to contain the frequently devastating epidemics in sub-Saharan Africa, the World Health Organization (WHO) Regional Office for Africa launched the Integrated Disease Surveillance and Response (IDSR) strategy in an effort to strengthen surveillance and response. However, 36 sub-Saharan African countries have been described as experiencing a human resource crisis by the WHO. Given this human resource situation, the challenge remains for these countries to achieve, among others, the health-related Millennium Development Goals (MDGs). This paper describes the process through which the African Field Epidemiology Network (AFENET) was developed, as well as how AFENET has contributed to addressing the public health workforce crisis, and the development of human resource capacity to implement IDSR in Africa. AFENET was established between 2005 and 2006 as a network of Field Epidemiology Training Programs (FETPs) and Field Epidemiology and Laboratory Training Programs (FELTPs) in Africa. This resulted from an expressed need to develop a network that would advocate for the unique needs of African FETPs and FELTPs, provide service to its membership, and through which programs could develop joint projects to address the public health needs of their countries. A total of eight new programs have been developed in sub-Saharan Africa since 2006. Programs established after 2006 represent over 70% of current FETP and FELTP enrolment in Africa. In addition to growth in membership and programs, AFENET has recorded significant growth in external partnerships. Beginning with USAID, CDC and WHO in 2004-2006, a total of at least 26 partners have been added by 2011. Drawing from lessons learnt, AFENET is now a resource that can be relied upon to expand public health capacity in Africa in an efficient and practical manner. National, regional and global health actors can leverage it to meet health-related targets at all levels. The AFENET story is one that continues to be driven

  10. Does malaria epidemiology project Cameroon as 'Africa in miniature'?

    PubMed

    Mbenda, Huguette Gaelle Ngassa; Awasthi, Gauri; Singh, Poonam K; Gouado, Inocent; Das, Aparup

    2014-09-01

    Cameroon, a west-central African country with a ~ 20 million population, is commonly regarded as 'Africa in miniature' due to the extensive biological and cultural diversities of whole Africa being present in a single-country setting. This country is inhabited by ancestral human lineages in unique eco-climatic conditions and diverse topography. Over 90 percent Cameroonians are at risk of malaria infection, and ~ 41 percent have at least one episode of malaria each year. Historically, the rate of malaria infection in Cameroon has fluctuated over the years; the number of cases was about 2 million in 2010 and 2011. The Cameroonian malaria control programme faces an uphill task due to high prevalence of multidrug-resistant parasites and insecticide-resistant malaria vectors. Above all, continued human migration from the rural to urban areas as well as population exchange with adjoining countries, high rate of ecological instabilities caused by deforestation, poor housing, lack of proper sanitation and drainage system might have resulted in the recent increase in incidences of malaria and other vector-borne diseases in Cameroon. The available data on eco-environmental variability and intricate malaria epidemiology in Cameroon reflect the situation in the whole of Africa, and warrant the need for in-depth study by using modern surveillance tools for meaningful basic understanding of the malaria triangle (host-parasite-vector-environment). PMID:25116627

  11. A clinico-epidemiological study of epidemic typhus in Africa.

    PubMed

    Perine, P L; Chandler, B P; Krause, D K; McCardle, P; Awoke, S; Habte-Gabr, E; Wisseman, C L; McDade, J E

    1992-05-01

    Epidemic, louse-borne typhus persists in the rugged, mountainous areas of Ethiopia and much of northeastern and central Africa as well as in the rural highlands of Central and South America, where the conditions of living favor the harboring of body lice and where antibiotic treatment and effective louse-control measures are unavailable. The historical significance and current epidemiology of typhus, including the reservoir of Rickettsia prowazekii in flying squirrels in the United States, are reviewed, and the clinical presentation, laboratory findings, and hospital course in the cases of 60 patients admitted with epidemic, louse-borne typhus to the St. Paul's Hospital in Addis Ababa, Ethiopia, are described. Treatment of this disease with oral doxycycline, tetracycline, or chloramphenicol prevents complications and results in prompt resolution of symptoms. PMID:1600020

  12. Agricultural fields, Khartoum, Sudan, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) is very distinctive in both size and shape. The region contains thousands of these rectangular fields bounded by canals which carry water from both the White and Blue Nile Rivers. A crop rotation system is used so that some fields are in cotton, millit, sorghum or fallow to conserve moisture and control weeds and insects. See also STS049-96-003.

  13. Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014

    PubMed Central

    Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

    2015-01-01

    As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3rd African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities. PMID:26523191

  14. The Molecular Epidemiology and Genetic Environment of Carbapenemases Detected in Africa.

    PubMed

    Sekyere, John Osei; Govinden, Usha; Essack, Sabiha

    2016-01-01

    Research articles describing carbapenemases and their genetic environments in Gram-negative bacteria were reviewed to determine the molecular epidemiology of carbapenemases in Africa. The emergence of resistance to the carbapenems, the last resort antibiotic for difficult to treat bacterial infections, affords clinicians few therapeutic options, with a resulting increase in morbidities, mortalities, and healthcare costs. However, the molecular epidemiology of carbapenemases throughout Africa is less described. Research articles and conference proceedings describing the genetic environment and molecular epidemiology of carbapenemases in Africa were retrieved from Google Scholar, Scifinder, Pubmed, Web of Science, and Science Direct databases. Predominant carbapenemase genes so far described in Africa include the blaOXA-48 type, blaIMP, blaVIM, and blaNDM in Acinetobacter baumannii, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter spp., and Escherichia coli carried on various plasmid types and sizes, transposons, and integrons. Class D and class B carbapenemases, mainly prevalent in A. baumannii, K. pneumoniae, E. cloacae, Citrobacter spp., and E. coli were the commonest carbapenemases. Carbapenemases are mainly reported in North and South Africa as under-resourced laboratories, lack of awareness and funding preclude the detection and reporting of carbapenemase-mediated resistance. Consequently, the true molecular epidemiology of carbapenemases and their genetic environment in Africa is still unknown.

  15. A systematic review of the epidemiology of hepatitis E virus in Africa

    PubMed Central

    2014-01-01

    Background Hepatitis E Virus (HEV) infection is a newly recognized serious threat to global public health and Africa is suspected to be among the most severely affected regions in the world. Understanding HEV epidemiology in Africa will expedite the implementation of evidence-based control policies aimed at preventing the spread of HEV including policies for the use of available resources such as HEV vaccines. Methods Here we present a comprehensive review of HEV epidemiology in Africa based on published data. We searched for articles on HEV epidemiology in Africa from online databases such as PubMed, Scopus, and ISI Web of Science and critically reviewed appropriate publications to extract consistent findings, identify knowledge gaps, and suggest future studies. Results Taking a particularly high toll in pregnant women and their fetuses, HEV has infected human populations in 28 of 56 African countries. Since 1979, 17 HEV outbreaks have been reported about once every other year from Africa causing a reported 35,300 cases with 650 deaths. Conclusions In Africa, HEV infection is not new, is widespread, and the number of reported outbreaks are likely a significant underestimate. The authors suggest that this is a continent-wide public health problem that deserves the attention of local, regional and international agencies to implement control policies that can save numerous lives, especially those of pregnant women and their fetuses. PMID:24902967

  16. Ebola virus disease in Africa: epidemiology and nosocomial transmission.

    PubMed

    Shears, P; O'Dempsey, T J D

    2015-05-01

    The 2014 Ebola outbreak in West Africa, primarily affecting Guinea, Sierra Leone, and Liberia, has exceeded all previous Ebola outbreaks in the number of cases and in international response. There have been 20 significant outbreaks of Ebola virus disease in Sub-Saharan Africa prior to the 2014 outbreak, the largest being that in Uganda in 2000, with 425 cases and a mortality of 53%. Since the first outbreaks in Sudan and Zaire in 1976, transmission within health facilities has been of major concern, affecting healthcare workers and acting as amplifiers of spread into the community. The lack of resources for infection control and personal protective equipment are the main reasons for nosocomial transmission. Local strategies to improve infection control, and a greater understanding of local community views on the disease, have helped to bring outbreaks under control. Recommendations from previous outbreaks include improved disease surveillance to enable more rapid health responses, the wider availability of personal protective equipment, and greater international preparedness.

  17. [Cost estimation of an epidemiological surveillance network for animal diseases in Central Africa: a case study of the Chad network].

    PubMed

    Ouagal, M; Berkvens, D; Hendrikx, P; Fecher-Bourgeois, F; Saegerman, C

    2012-12-01

    In sub-Saharan Africa, most epidemiological surveillance networks for animal diseases were temporarily funded by foreign aid. It should be possible for national public funds to ensure the sustainability of such decision support tools. Taking the epidemiological surveillance network for animal diseases in Chad (REPIMAT) as an example, this study aims to estimate the network's cost by identifying the various costs and expenditures for each level of intervention. The network cost was estimated on the basis of an analysis of the operational organisation of REPIMAT, additional data collected in surveys and interviews with network field workers and a market price listing for Chad. These costs were then compared with those of other epidemiological surveillance networks in West Africa. The study results indicate that REPIMAT costs account for 3% of the State budget allocated to the Ministry of Livestock. In Chad in general, as in other West African countries, fixed costs outweigh variable costs at every level of intervention. The cost of surveillance principally depends on what is needed for surveillance at the local level (monitoring stations) and at the intermediate level (official livestock sectors and regional livestock delegations) and on the cost of the necessary equipment. In African countries, the cost of surveillance per square kilometre depends on livestock density.

  18. Epidemiology of Coxiella burnetii Infection in Africa: A OneHealth Systematic Review

    PubMed Central

    Vanderburg, Sky; Rubach, Matthew P.; Halliday, Jo E. B.; Cleaveland, Sarah; Reddy, Elizabeth A.; Crump, John A.

    2014-01-01

    Background Q fever is a common cause of febrile illness and community-acquired pneumonia in resource-limited settings. Coxiella burnetii, the causative pathogen, is transmitted among varied host species, but the epidemiology of the organism in Africa is poorly understood. We conducted a systematic review of C. burnetii epidemiology in Africa from a “One Health” perspective to synthesize the published data and identify knowledge gaps. Methods/Principal Findings We searched nine databases to identify articles relevant to four key aspects of C. burnetii epidemiology in human and animal populations in Africa: infection prevalence; disease incidence; transmission risk factors; and infection control efforts. We identified 929 unique articles, 100 of which remained after full-text review. Of these, 41 articles describing 51 studies qualified for data extraction. Animal seroprevalence studies revealed infection by C. burnetii (≤13%) among cattle except for studies in Western and Middle Africa (18–55%). Small ruminant seroprevalence ranged from 11–33%. Human seroprevalence was <8% with the exception of studies among children and in Egypt (10–32%). Close contact with camels and rural residence were associated with increased seropositivity among humans. C. burnetii infection has been associated with livestock abortion. In human cohort studies, Q fever accounted for 2–9% of febrile illness hospitalizations and 1–3% of infective endocarditis cases. We found no studies of disease incidence estimates or disease control efforts. Conclusions/Significance C. burnetii infection is detected in humans and in a wide range of animal species across Africa, but seroprevalence varies widely by species and location. Risk factors underlying this variability are poorly understood as is the role of C. burnetii in livestock abortion. Q fever consistently accounts for a notable proportion of undifferentiated human febrile illness and infective endocarditis in cohort studies, but

  19. Hepatitis B epidemiology in Asia, the Middle East and Africa.

    PubMed

    André, F

    2000-02-18

    Asia and Africa have previously been classified as areas of high endemicity for hepatitis B virus (HBV), but in some countries highly effective vaccination programmes have shifted this pattern towards intermediate or low endemicity. Thus, China is now the only country in Asia where HBV endemicity is high. Countries with intermediate endemicity include India, Korea, the Philippines, Taiwan and Thailand, and those with low endemicity include Japan, Pakistan, Bangladesh, Singapore, Sri Lanka and Malaysia. Most countries in Africa have high HBV endemicity, with the exceptions of Tunisia and Morocco, which have intermediate endemicity. Zambia has borderline intermediate/high endemicity. In the Middle East, Bahrain, Iran, Israel and Kuwait are areas of low endemicity, Cyprus, Iraq and the United Arab Emirates have intermediate endemicity, and Egypt, Jordan, Oman, Palestine, Yemen and Saudi Arabia have high endemicity. All of these Middle East countries reach a large proportion of their population with hepatitis B vaccination, which is reducing the infection rate, particularly in Saudi Arabia. The vaccination programme in Taiwan has also greatly reduced the HBV infection rate. Future vaccination programmes must take into account the mode of transmission of HBV, the healthcare infrastructure to deliver vaccination, and the socioeconomic and political factors in each individual country, to determine the most cost-effective way of infection control.

  20. Epidemiology and molecular virus characterization of reemerging rabies, South Africa.

    PubMed

    Cohen, Cheryl; Sartorius, Benn; Sabeta, Claude; Zulu, Gugulethu; Paweska, Janusz; Mogoswane, Mamokete; Sutton, Chris; Nel, Louis H; Swanepoel, Robert; Leman, Patricia A; Grobbelaar, Antoinette A; Dyason, Edwin; Blumberg, Lucille

    2007-12-01

    The incidence of dog rabies in Limpopo Province, South Africa, increased from 5 cases in 2004 to 100 in 2006. Human rabies had last been confirmed in 1981, but investigations instituted after an index case was recognized in February 2006 identified 21 confirmed, 4 probable, and 5 possible human cases between August 5, 2005, and December 31, 2006. Twelve of these case-patients were identified retrospectively because the diagnosis of rabies was not considered: 6 of these patients consulted a traditional healer, 6 had atypical manifestations with prominent abdominal symptoms, and 6 of 7 patients tested had elevated liver enzyme activity. Molecular genetic analysis indicated that outbreak virus strains were most closely related to recent canine strains from southern Zimbabwe. Delayed recognition of the human cases may have resulted from decreased clinical suspicion after many years of effective control of the disease and the occurrence of atypical clinical presentations. PMID:18258039

  1. An epidemiological investigation of Norwalk virus infection in South Africa.

    PubMed Central

    Taylor, M. B.; Parker, S.; Grabow, W. O.; Cubitt, W. D.

    1996-01-01

    A study was carried out to determine the incidence and seroprevalence of Norwalk virus (NV) in the Pretoria area, South Africa, using a recombinant NV (rNV) immunoassay for the detection of serum IgG antibodies. Maternal antibody was detectable in infants' sera up to approximately 6 months of age. Infection with NV was detected serologically in the second year of life and the seroprevalence of NV IgG rose from 37.1% at 7-11 months of age to 62.1% by the age of 40 years. No significant differences in seroprevalence of NV IgG antibody was evident between subjects of European or African ethnic origin, where overall seroprevalence rates were 56.4% and 53.9% respectively. PMID:8620912

  2. Epidemiology and molecular virus characterization of reemerging rabies, South Africa.

    PubMed

    Cohen, Cheryl; Sartorius, Benn; Sabeta, Claude; Zulu, Gugulethu; Paweska, Janusz; Mogoswane, Mamokete; Sutton, Chris; Nel, Louis H; Swanepoel, Robert; Leman, Patricia A; Grobbelaar, Antoinette A; Dyason, Edwin; Blumberg, Lucille

    2007-12-01

    The incidence of dog rabies in Limpopo Province, South Africa, increased from 5 cases in 2004 to 100 in 2006. Human rabies had last been confirmed in 1981, but investigations instituted after an index case was recognized in February 2006 identified 21 confirmed, 4 probable, and 5 possible human cases between August 5, 2005, and December 31, 2006. Twelve of these case-patients were identified retrospectively because the diagnosis of rabies was not considered: 6 of these patients consulted a traditional healer, 6 had atypical manifestations with prominent abdominal symptoms, and 6 of 7 patients tested had elevated liver enzyme activity. Molecular genetic analysis indicated that outbreak virus strains were most closely related to recent canine strains from southern Zimbabwe. Delayed recognition of the human cases may have resulted from decreased clinical suspicion after many years of effective control of the disease and the occurrence of atypical clinical presentations.

  3. Demographic, epidemiological, and health transitions: are they relevant to population health patterns in Africa?

    PubMed Central

    Kuate Defo, Barthélémy

    2014-01-01

    Background Studies of trends in population changes and epidemiological profiles in the developing world have overwhelmingly relied upon the concepts of demographic, epidemiological, and health transitions, even though their usefulness in describing and understanding population and health trends in developing countries has been repeatedly called into question. The issue is particularly relevant for the study of population health patterns in Africa and sub-Saharan Africa, as the history and experience there differs substantially from that of Western Europe and North America, for which these concepts were originally developed. Objective The aim of this study is two-fold: to review and clarify any distinction between the concepts of demographic transition, epidemiological transition and health transition and to identify summary indicators of population health to test how well these concepts apply in Africa. Results Notwithstanding the characteristically diverse African context, Africa is a continent of uncertainties and emergencies where discontinuities and interruptions of health, disease, and mortality trends reflect the enduring fragility and instability of countries and the vulnerabilities of individuals and populations in the continent. Africa as a whole remains the furthest behind the world's regions in terms of health improvements and longevity, as do its sub-Saharan African regions and societies specifically. This study documents: 1) theoretically and empirically the similarities and differences between the demographic transition, epidemiological transition, and health transition; 2) simple summary indicators that can be used to evaluate their descriptive and predictive features; 3) marked disparities in the onset and pace of variations and divergent trends in health, disease, and mortality patterns as well as fertility and life expectancy trajectories among African countries and regions over the past 60 years; 4) the rapid decline in infant mortality and gains

  4. Linking avian communities and avian influenza ecology in southern Africa using epidemiological functional groups.

    PubMed

    Caron, Alexandre; de Garine-Wichatitsky, Michel; Ndlovu, Mduduzi; Cumming, Graeme S

    2012-01-01

    The ecology of pathogens, and particularly their emergence in multi-host systems, is complex. New approaches are needed to reduce superficial complexities to a level that still allows scientists to analyse underlying and more fundamental processes. One promising approach for simplification is to use an epidemiological-function classification to describe ecological diversity in a way that relates directly to pathogen dynamics. In this article, we develop and apply the epidemiological functional group (EFG) concept to explore the relationships between wild bird communities and avian influenza virus (AIV) in three ecosystems in southern Africa. Using a two year dataset that combined bird counts and bimonthly sampling for AIV, we allocated each bird species to a set of EFGs that captured two overarching epidemiological functions: the capacity of species to maintain AIV in the system, and their potential to introduce the virus. Comparing AIV prevalence between EFGs suggested that the hypothesis that anseriforms (ducks) and charadriiforms (waders) drive AIV epidemiology cannot entirely explain the high prevalence observed in some EFGs. If anseriforms do play an important role in AIV dynamics in each of the three ecosystems, the role of other species in the local maintenance of AIV cannot be ruled out. The EFG concept thus helped us to identify gaps in knowledge and to highlight understudied bird groups that might play a role in AIV epidemiology. In general, the use of EFGs has potential for generating a range of valuable insights in epidemiology, just as functional group approaches have done in ecology. PMID:23101696

  5. Atrial fibrillation in Sub-Saharan Africa: epidemiology, unmet needs, and treatment options

    PubMed Central

    Stambler, Bruce Sheldon; Ngunga, Leonard M

    2015-01-01

    Health care in Sub-Saharan Africa is being challenged by a double burden of disease as lifestyle diseases common in the developed world, such as stroke and atrial fibrillation (AF), increase, while, simultaneously, health issues of the developing world in terms of communicable disease persist. The prevalence of AF is lower in Africa than in the developed world but is expected to increase significantly over the next few decades. Patients with AF in Africa tend to be younger and have a higher prevalence of rheumatic valvular heart disease than patients with AF in other regions. Permanent AF is the most prevalent type of AF in Africa, possibly due to the lower use of rhythm control strategies than in the developed world. Mortality rates of patients with AF in Africa are high, due largely to poor health care access and suboptimal therapy. The risk of stroke in AF, which is moderate to high in Africans as in the developed world, contributes to the high mortality rate. Patients with AF in Africa are often undertreated with antithrombotics, as cost and access to monitoring are major barriers. Vitamin K antagonists, including warfarin, are the most commonly available oral anticoagulants, but regular monitoring can be challenging, especially for patients in remote areas. Several non-vitamin K antagonist oral anticoagulants (NOACs) have been approved for use in countries across Sub-Saharan Africa and have the potential to reduce stroke burden. The higher cost of newer agents may be offset by the reduced need for regular monitoring, fixed dosing, and lower risk of intracranial bleeding; NOACs could provide a treatment option for patients in remote areas with limited access to regular monitoring. However, NOACs are not indicated in valvular AF. More work is needed to increase understanding of the epidemiology of AF and stroke, as well as to improve management strategies to reduce the burden of cardiovascular disease predicted for Africa. PMID:26261423

  6. Ebola virus disease outbreak; the role of field epidemiology training programme in the fight against the epidemic, Liberia, 2014

    PubMed Central

    Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod

    2015-01-01

    The African Field Epidemiology Network (AFENET) is a public health network established in 2005 as a non-profit networking alliance of Field Epidemiology and Laboratory Training Programs (FELTPs) and Field Epidemiology Training Programs (FETPs) in Africa. AFENET is dedicated to supporting Ministries of Health in Africa build strong, effective and sustainable programs and capacity to improve public health systems by partnering with global public health experts. The Network's goal is to strengthen field epidemiology and public health laboratory capacity to contribute effectively to addressing epidemics and other major public health problems in Africa. The goal for the establishment of FETP and FELTP was and still is to produce highly competent multi-disciplinary public health professionals who would assume influential posts in the public health structures and tackle emerging and re-emerging communicable and non-communicable diseases. AFENET currently networks 12 FELTPs and FETPs in sub-Saharan Africa with operations in 20 countries. During the Ebola Virus Disease (EVD) outbreak in West Africa, African Union Support for the Ebola Outbreak in West Africa (ASEOWA) supported FETP graduates from Uganda, Zimbabwe, Ethiopia and Tanzania for the investigation and control of the EVD outbreak in Liberia. The graduates were posted in different counties in Liberia where they lead teams of other experts conduct EVD outbreak investigations, Infection Control and Prevention trainings among health workers and communities, Strengthening integrated disease surveillance, developing Standard Operating Procedures for infection control and case notification in the Liberian setting as well as building capacity of local surveillance officers’ conduct outbreak investigation and contact tracing. The team was also responsible for EVD data management at the different Counties in Liberia. The FETP graduates have been instrumental in the earlier successes registered in various counties in

  7. HIV related pulmonary arterial hypertension: epidemiology in Africa, physiopathology, and role of antiretroviral treatment.

    PubMed

    Bigna, Jean Joel R; Sime, Paule Sandra D; Koulla-Shiro, Sinata

    2015-01-01

    The development of HIV related pulmonary arterial hypertension (PAH) reduces the probability of survival by half as compared with HIV-infected individuals without HIV related PAH. HIV infected patients have a greater incidence of PAH compared to general population and have a 2500-fold increased risk of developing PAH. It is therefore important to have a recent overview of the problem in Africa, the most HIV affected part of the world (70 % of all HIV infection in the world). First, we discussed the epidemiology of HIV-related PAH in Africa. Second, the current understanding of the HIV-related PAH pathogenesis has been covered. Third, role of highly active antiretroviral therapy on HIV-related PAH has been revisited. There are few data concerning epidemiology of HIV related pulmonary hypertension in Africa leading to necessity to conduct further prospective large studies. The prevalence of PAH among HIV infected people in Africa varies from 5 to 13 %. The prevalence of HIV-related PAH in Africa is notably high compared to those in developed countries and in general population. The pathogenesis of PAH is clearly complex, and probably results from the interaction of multiple modulating genes with environmental factors. The physiopathology includes cytokines secretion increase which induces dysregulation of endothelial and vascular smooth muscle cell growth and imbalance of endogenous vasodilators and constrictors; HIV viral proteins which induces vascular oxidative stress, smooth myocyte proliferation and migration, and endothelial injury and genetic predisposition due to some major histocompatibility complex alleles, particularly HDL-DR6 and HLA-DR5. Histologically, HIV related PAH has the same characteristics with other types PAH. Antiretroviral therapy have a beneficial effect on the outcome of HIV related pulmonary hypertension, but it lacks evidence from large prospective studies.

  8. Molecular Epidemiology of Human Rhinoviruses and Enteroviruses Highlights Their Diversity in Sub-Saharan Africa.

    PubMed

    L'Huillier, Arnaud G; Kaiser, Laurent; Petty, Tom J; Kilowoko, Mary; Kyungu, Esther; Hongoa, Philipina; Vieille, Gaël; Turin, Lara; Genton, Blaise; D'Acremont, Valérie; Tapparel, Caroline

    2015-12-08

    Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Enterovirus genus and are the most frequent cause of infection worldwide, but data on their molecular epidemiology in Africa are scarce. To understand HRV and HEV molecular epidemiology in this setting, we enrolled febrile pediatric patients participating in a large prospective cohort assessing the causes of fever in Tanzanian children. Naso/oropharyngeal swabs were systematically collected and tested by real-time RT-PCR for HRV and HEV. Viruses from positive samples were sequenced and phylogenetic analyses were then applied to highlight the HRV and HEV types as well as recombinant or divergent strains. Thirty-eight percent (378/1005) of the enrolled children harboured an HRV or HEV infection. Although some types were predominant, many distinct types were co-circulating, including a vaccinal poliovirus, HEV-A71 and HEV-D68. Three HRV-A recombinants were identified: HRV-A36/HRV-A67, HRV-A12/HRV-A67 and HRV-A96/HRV-A61. Four divergent HRV strains were also identified: one HRV-B strain and three HRV-C strains. This is the first prospective study focused on HRV and HEV molecular epidemiology in sub-Saharan Africa. This systematic and thorough large screening with careful clinical data management confirms the wide genomic diversity of these viruses, brings new insights about their evolution and provides data about associated symptoms.

  9. Molecular Epidemiology of Human Rhinoviruses and Enteroviruses Highlights Their Diversity in Sub-Saharan Africa

    PubMed Central

    L’Huillier, Arnaud G.; Kaiser, Laurent; Petty, Tom J.; Kilowoko, Mary; Kyungu, Esther; Hongoa, Philipina; Vieille, Gaël; Turin, Lara; Genton, Blaise; D’Acremont, Valérie; Tapparel, Caroline

    2015-01-01

    Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Enterovirus genus and are the most frequent cause of infection worldwide, but data on their molecular epidemiology in Africa are scarce. To understand HRV and HEV molecular epidemiology in this setting, we enrolled febrile pediatric patients participating in a large prospective cohort assessing the causes of fever in Tanzanian children. Naso/oropharyngeal swabs were systematically collected and tested by real-time RT-PCR for HRV and HEV. Viruses from positive samples were sequenced and phylogenetic analyses were then applied to highlight the HRV and HEV types as well as recombinant or divergent strains. Thirty-eight percent (378/1005) of the enrolled children harboured an HRV or HEV infection. Although some types were predominant, many distinct types were co-circulating, including a vaccinal poliovirus, HEV-A71 and HEV-D68. Three HRV-A recombinants were identified: HRV-A36/HRV-A67, HRV-A12/HRV-A67 and HRV-A96/HRV-A61. Four divergent HRV strains were also identified: one HRV-B strain and three HRV-C strains. This is the first prospective study focused on HRV and HEV molecular epidemiology in sub-Saharan Africa. This systematic and thorough large screening with careful clinical data management confirms the wide genomic diversity of these viruses, brings new insights about their evolution and provides data about associated symptoms. PMID:26670243

  10. Molecular Epidemiology of Human Rhinoviruses and Enteroviruses Highlights Their Diversity in Sub-Saharan Africa.

    PubMed

    L'Huillier, Arnaud G; Kaiser, Laurent; Petty, Tom J; Kilowoko, Mary; Kyungu, Esther; Hongoa, Philipina; Vieille, Gaël; Turin, Lara; Genton, Blaise; D'Acremont, Valérie; Tapparel, Caroline

    2015-12-01

    Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Enterovirus genus and are the most frequent cause of infection worldwide, but data on their molecular epidemiology in Africa are scarce. To understand HRV and HEV molecular epidemiology in this setting, we enrolled febrile pediatric patients participating in a large prospective cohort assessing the causes of fever in Tanzanian children. Naso/oropharyngeal swabs were systematically collected and tested by real-time RT-PCR for HRV and HEV. Viruses from positive samples were sequenced and phylogenetic analyses were then applied to highlight the HRV and HEV types as well as recombinant or divergent strains. Thirty-eight percent (378/1005) of the enrolled children harboured an HRV or HEV infection. Although some types were predominant, many distinct types were co-circulating, including a vaccinal poliovirus, HEV-A71 and HEV-D68. Three HRV-A recombinants were identified: HRV-A36/HRV-A67, HRV-A12/HRV-A67 and HRV-A96/HRV-A61. Four divergent HRV strains were also identified: one HRV-B strain and three HRV-C strains. This is the first prospective study focused on HRV and HEV molecular epidemiology in sub-Saharan Africa. This systematic and thorough large screening with careful clinical data management confirms the wide genomic diversity of these viruses, brings new insights about their evolution and provides data about associated symptoms. PMID:26670243

  11. Epidemiology of Histologically Proven Glomerulonephritis in Africa: A Systematic Review and Meta-Analysis

    PubMed Central

    Okpechi, Ikechi G.; Ameh, Oluwatoyin I.; Bello, Aminu K.; Ronco, Pierre; Swanepoel, Charles R.; Kengne, Andre P.

    2016-01-01

    Background and aim Glomerulonephritis (GN) is a leading cause of end-stage renal disease (ESRD) in Africa. Data on epidemiology and outcomes of glomerular diseases from Africa is still limited. We conducted a systematic review on the epidemiology of histologically proven glomerular diseases in Africa between 1980 and 2014. Materials and methods We searched literature using PubMed, AfricaWide, the Cumulative Index to Nursing and Allied Health Literature on EBSCO Host, Scopus, African Journals online databases, and the African Index Medicus, for relevant studies. The review was conducted using standard methods and frameworks using only biopsy-confirmed data. Results Twenty four (24) studies comprising 12,093 reported biopsies from 13 countries were included in this analysis. The median number of biopsies per study was 127.0 (50–4436), most of the studies (70.0%) originated from North Africa and the number of performed kidney biopsies varied from 5.2 to 617 biopsies/year. Nephrotic syndrome was the commonest indication of renal biopsy. The frequency of reported primary pathologic patterns included, minimal change disease (MCD); 16.5% (95%CI: 11.2–22.6), focal segmental glomerulosclerosis (FSGS); 15.9% (11.3–21.1), mesangiocapillary GN (MCGN); 11.8% (9.2–14.6), crescentic GN; 2.0% (0.9–3.5) and IgA nephropathy 2.8% (1.3–4.9). Glomerular diseases related to hepatitis B and systemic lupus erythematosus had the highest prevalence among assessed secondary diseases: 8.4% (2.0–18.4) and 7.7% (4.5–11.7) respectively. There was no evidence of publication bias and regional differences were seen mostly for secondary GNs. Conclusions Glomerular diseases remain poorly characterized in sub-Saharan Africa due to declining renal biopsy rates and consequent paucity of data on pathologic patterns of key renal diseases. Development of renal biopsy registries in Africa is likely to enable adequate characterization of the prevalence and patterns of glomerular diseases

  12. 'Deadly gonorrhoea': history, collective memory and early HIV epidemiology in East Central Africa.

    PubMed

    Kuhanen, Jan

    2015-01-01

    This article combines local oral reminiscences with recent epidemiological literature to sketch a historical context around the onset and expansion of the HIV-1 epidemic in southern Uganda and north-western Tanzania. The local historical imagination has associated the appearance of AIDS in two ways. First, with specific socio-economic structures and circumstances common in the region since the 1960s and their enhancement during the 1970s due to economic changes at national and global levels. Second, the epidemic is associated with changes in the epidemiological situation. Local perspectives are supported by recent phylogenetic research and circumstantial historical evidence, on the basis of which a hypothesis on the expansion of HIV-1 in East Central Africa (southern Uganda, north-western Tanzania, Rwanda) is presented.

  13. Injuries as a public health problem in sub-Saharan Africa: epidemiology and prospects for control.

    PubMed

    Nordberg, E

    2000-12-01

    Injuries are common and on increase in most developing countries, including sub-Saharan Africa. A large proportion of the injuries are caused by road traffic accidents, falls, burns, assaults, bites, stings and other animal-related injuries, poisonings, drownings/near-drownings and suicide. Globally, injuries are responsible for about five per cent of the total mortality, and the overall global annual costs were estimated in the late 1980s at around 500 billion US dollars. The burden and pattern of injuries in Africa and other developing areas are poorly known and not well studied. The incidence is on the increase, partly due to rapid growth of motorised transport and to expansion of industrial production without adequate safety precautions. This is a review of data on various kinds of injuries in developing countries with a focus on sub-Saharan Africa. A computerised search of the relevant literature published between 1985 and 1998 was conducted and a manual search of journals publishing texts on health in low-income countries and in tropical environments was also done. A few studies on injury prevention policy and on research related to injury epidemiology and prevention have also been identified and included. It is concluded that in a relatively typical East African area with a total mortality rate of 1,300/100,000/year, injuries are likely to cause around 100 of these deaths. The corresponding total rate of significant injuries is estimated at 40,000/100,000/year with a breakdown as tabulated below. [table: see text] Although a few surveys and other investigations of injuries have been conducted over the years, injury epidemiology and control remain under-researched and relatively neglected subject areas. Much needs to be done. Collection and analysis of injury data need to be standardised, for example regarding age groups, gender disaggregation and severity. Injuries and accidents should be subdivided in at least road traffic injury, fall, burn, assault

  14. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    PubMed

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants. PMID:24802562

  15. Remote sensing, geographical information system and spatial analysis for schistosomiasis epidemiology and ecology in Africa.

    PubMed

    Simoonga, C; Utzinger, J; Brooker, S; Vounatsou, P; Appleton, C C; Stensgaard, A S; Olsen, A; Kristensen, T K

    2009-11-01

    Beginning in 1970, the potential of remote sensing (RS) techniques, coupled with geographical information systems (GIS), to improve our understanding of the epidemiology and control of schistosomiasis in Africa, has steadily grown. In our current review, working definitions of RS, GIS and spatial analysis are given, and applications made to date with RS and GIS for the epidemiology and ecology of schistosomiasis in Africa are summarised. Progress has been made in mapping the prevalence of infection in humans and the distribution of intermediate host snails. More recently, Bayesian geostatistical modelling approaches have been utilized for predicting the prevalence and intensity of infection at different scales. However, a number of challenges remain; hence new research is needed to overcome these limitations. First, greater spatial and temporal resolution seems important to improve risk mapping and understanding of transmission dynamics at the local scale. Second, more realistic risk profiling can be achieved by taking into account information on people's socio-economic status; furthermore, future efforts should incorporate data on domestic access to clean water and adequate sanitation, as well as behavioural and educational issues. Third, high-quality data on intermediate host snail distribution should facilitate validation of infection risk maps and modelling transmission dynamics. Finally, more emphasis should be placed on risk mapping and prediction of multiple species parasitic infections in an effort to integrate disease risk mapping and to enhance the cost-effectiveness of their control. PMID:19627627

  16. Remote sensing, geographical information system and spatial analysis for schistosomiasis epidemiology and ecology in Africa

    PubMed Central

    SIMOONGA, C.; UTZINGER, J.; BROOKER, S.; VOUNATSOU, P.; APPLETON, C. C.; STENSGAARD, A. S.; OLSEN, A.; KRISTENSEN, T. K.

    2009-01-01

    Summary Beginning in 1970, the potential of remote sensing (RS) techniques, coupled with geographical information systems (GIS), to improve our understanding of the epidemiology and control of schistosomiasis in Africa, has steadily grown. In our current review, working definitions of RS, GIS and spatial analysis are given, and applications made to date with RS and GIS for the epidemiology and ecology of schistosomiasis in Africa are summarised. Progress has been made in mapping the prevalence of infection in humans and the distribution of intermediate host snails. More recently, Bayesian geostatistical modelling approaches have been utilized for predicting the prevalence and intensity of infection at different scales. However, a number of challenges remain; hence new research is needed to overcome these limitations. First, greater spatial and temporal resolution seems important to improve risk mapping and understanding of transmission dynamics at the local scale. Second, more realistic risk profiling can be achieved by taking into account information on people's socio-economic status; furthermore, future efforts should incorporate data on domestic access to clean water and adequate sanitation, as well as behavioural and educational issues. Third, high-quality data on intermediate host snail distribution should facilitate validation of infection risk maps and modelling transmission dynamics. Finally, more emphasis should be placed on risk mapping and prediction of multiple species parasitic infections in an effort to integrate disease risk mapping and to enhance the cost-effectiveness of their control. PMID:19627627

  17. Essential evidence for guiding health system priorities and policies: anticipating epidemiological transition in Africa

    PubMed Central

    Byass, Peter; de Savigny, Don; Lopez, Alan D.

    2014-01-01

    Background Despite indications that infection-related mortality in sub-Saharan Africa may be decreasing and the burden of non-communicable diseases increasing, the overwhelming reality is that health information systems across most of sub-Saharan Africa remain too weak to track epidemiological transition in a meaningful and effective way. Proposals We propose a minimum dataset as the basis of a functional health information system in countries where health information is lacking. This would involve continuous monitoring of cause-specific mortality through routine civil registration, regular documentation of exposure to leading risk factors, and monitoring effective coverage of key preventive and curative interventions in the health sector. Consideration must be given as to how these minimum data requirements can be effectively integrated within national health information systems, what methods and tools are needed, and ensuring that ethical and political issues are addressed. A more strategic approach to health information systems in sub-Saharan African countries, along these lines, is essential if epidemiological changes are to be tracked effectively for the benefit of local health planners and policy makers. Conclusion African countries have a unique opportunity to capitalize on modern information and communications technology in order to achieve this. Methodological standards need to be established and political momentum fostered so that the African continent's health status can be reliably tracked. This will greatly strengthen the evidence base for health policies and facilitate the effective delivery of services. PMID:24848653

  18. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    PubMed

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants.

  19. Epidemiology and evolution of the genetic variability of Anaplasma marginale in South Africa.

    PubMed

    Mutshembele, Awelani M; Cabezas-Cruz, Alejandro; Mtshali, Moses S; Thekisoe, Oriel M M; Galindo, Ruth C; de la Fuente, José

    2014-10-01

    Bovine anaplasmosis caused by infection of cattle with Anaplasma marginale has been considered to be endemic in South Africa, an assumption based primarily on the distribution of the tick vectors of A. marginale and serological studies on the prevalence of anaplasmosis in Limpopo, Free State, and North West. However, molecular evidence of the distribution of anaplasmosis has only been reported in the Free State province. In order to establish effective control measures for anaplasmosis, epidemiological surveys are needed to define the prevalence and distribution of A. marginale in South Africa. In addition, a proposed control strategy for anaplasmosis is the development of an A. marginale major surface protein 1a (MSP1a)-based vaccine. Nevertheless, regional variations of this gene would need to be characterized prior to vaccine development for South Africa. The objectives of the present study were therefore to conduct a national survey of the prevalence of A. marginale in South Africa, followed by an evaluation of the diversity and evolution of msp1a in South African strains of A. marginale. To accomplish these objectives, species-specific PCR was used to test 250 blood samples from cattle collected from all South African provinces (including 26 districts and municipalities), except the Free State province where similar studies were reported previously. The prevalence of A. marginale ranged from 65% to 100%, except in Northern Cape province where A. marginale was not detected. A correlation was found between the prevalence and genetic diversity of A. marginale MSP1a. Additionally, the genetic diversity of the A. marginale MSP1a was found to evolve under negative and positive selection, and 23 new tandem repeats in South Africa were shown to have evolved from the extant tandem repeat 4. Despite the MSP1a genetic variability, some types of tandem repeats were found to be conserved among the A. marginale strains, and low-variable peptides in MSP1a tandem repeats were

  20. Epidemiology of major depressive disorder in South Africa (1997–2015): a systematic review protocol

    PubMed Central

    Nglazi, Mweete D; Joubert, Jané D; Stein, Dan J; Lund, Crick; Wiysonge, Charles S; Vos, Theo; Pillay-van Wyk, Victoria; Roomaney, Rifqah A; Muhwava, Lorrein S; Bradshaw, Debbie

    2016-01-01

    Introduction Major depressive disorder (MDD) is a leading cause of disease and disability globally and in South Africa. Epidemiological data for MDD are essential to estimate the overall disease burden in a country. The objective of the systematic review is to examine the evidence base for prevalence, incidence, remission, duration, severity, case fatality and excess mortality of MDD in South Africa from 1997 to 2015. Methods and analysis We will perform electronic searches in PubMed, PsycINFO, Scopus and other bibliographical databases. Articles published between January 1997 and December 2015 will be eligible for inclusion in this review. The primary outcomes will be prevalence, incidence, remission, duration, severity, case fatality and excess mortality of MDD. The secondary outcomes will be risk factors and selected populations for MDD. If appropriate, a meta-analysis will be performed. If a meta-analysis is not possible, the review findings will be presented narratively and in tables. Subgroup analyses will be conducted with subgroups defined by population group, rural/urban settings and study designs, if sufficient data are available. Ethics and dissemination The systematic review will use published data that are not linked to individuals. The review findings may have implications for future research prioritisation and disease modelling of MDD to estimate its morbidity burden in South Africa, and will be disseminated electronically and in print through peer-reviewed publications. Trial Registration number: International Prospective Register of Systematic Reviews (PROSPERO) CRD42015024885. PMID:27377639

  1. Taenia solium taeniosis/cysticercosis in Africa: risk factors, epidemiology and prospects for control using vaccination.

    PubMed

    Assana, Emmanuel; Lightowlers, Marshall W; Zoli, André P; Geerts, Stanny

    2013-07-01

    Poor sanitary conditions, free-roaming of domestic pigs and lack of awareness of the disease play an important role in the perpetuation of the Taenia solium taeniosis and cysticercosis in Africa. Traditional pig production systems known as the source of T. solium taeniosis/cysticercosis complex are predominant in the continent, representing 60-90% of pig production in rural areas. It has been reported that T. solium cysticercosis is the main cause of acquired epilepsy in human population and results in considerable public health problems and economic costs to the endemic countries. Although the socioeconomic impact and public health burden of cysticercosis have been demonstrated, up to now no large-scale control programme has been undertaken in Africa. Most disease control trials reported in the literature have been located in Latin America and Asia. This review discusses the risk factors and epidemiology of T. solium cysticercosis in Africa and critically analyzes the options available for implementing control of this zoonotic disease in the continent.

  2. Cardiovascular Risk Factor Burden in Africa and the Middle East: The Africa Middle East Cardiovascular Epidemiological (ACE) Study

    PubMed Central

    Alsheikh-Ali, Alawi A.; Omar, Mohamed I.; Raal, Frederick J.; Rashed, Wafa; Hamoui, Omar; Kane, Abdoul; Alami, Mohamed; Abreu, Paula; Mashhoud, Walid M.

    2014-01-01

    Background Increased urbanization in the developing world parallels a rising burden of chronic diseases. Developing countries account for ∼80% of global cardiovascular (CV) deaths, but contribute a paucity of systematic epidemiological data on CV risk factors. Objective To estimate the prevalence of CV risk factors in rural and urban cohorts attending general practice clinics in the Africa and Middle East (AfME) region. Methods In a cross-sectional epidemiological study, the presence of CV risk factors (hypertension, diabetes mellitus (diabetes), dyslipidemia, obesity, smoking and abdominal obesity) were evaluated in stable adult outpatients attending general practice primary care clinics. A rural population was defined as isolated (>50 km or lack of easy access to commuter transportation) from urban centers. Results 4,378 outpatients were systematically recruited from 94 clinics across 14 AfME countries. Mean age was 46±14 years and 52% of outpatients were female. A high prevalence of dyslipidemia (70%) and abdominal obesity (68%) were observed, followed by hypertension (43%) and diabetes (25%). The vast majority of outpatients (92%) had at least one modifiable CV risk factor, many (74%) had more than one, and half (53%) had 3 or more. These findings were observed in both genders and across urban and rural centers. Among outpatients with pre-existing hypertension or dyslipidemia, many were not at their target blood pressure or LDL-cholesterol goals. Conclusion Cardiovascular risk factors are highly prevalent among relatively young, stable outpatients attending general practice clinics across AfME. The findings support opportunistic screening for CV risk factors whenever outpatients visit a general practitioner and provide an opportunity for early identification and management of CV risk factors, including lifestyle interventions. PMID:25090638

  3. Training and service in public health, Nigeria Field Epidemiology and Laboratory Training, 2008 - 2014.

    PubMed

    Nguku, Patrick; Oyemakinde, Akin; Sabitu, Kabir; Olayinka, Adebola; Ajayi, Ikeoluwapo; Fawole, Olufunmilayo; Babirye, Rebecca; Gitta, Sheba; Mukanga, David; Waziri, Ndadilnasiya; Gidado, Saheed; Biya, Oladayo; Gana, Chinyere; Ajumobi, Olufemi; Abubakar, Aisha; Sani-Gwarzo, Nasir; Ngobua, Samuel; Oleribe, Obinna; Poggensee, Gabriele; Nsubuga, Peter; Nyager, Joseph; Nasidi, Abdulsalami

    2014-01-01

    The health workforce is one of the key building blocks for strengthening health systems. There is an alarming shortage of curative and preventive health care workers in developing countries many of which are in Africa. Africa resultantly records appalling health indices as a consequence of endemic and emerging health issues that are exacerbated by a lack of a public health workforce. In low-income countries, efforts to build public health surveillance and response systems have stalled, due in part, to the lack of epidemiologists and well-trained laboratorians. To strengthen public health systems in Africa, especially for disease surveillance and response, a number of countries have adopted a competency-based approach of training - Field Epidemiology and Laboratory Training Program (FELTP). The Nigeria FELTP was established in October 2008 as an inservice training program in field epidemiology, veterinary epidemiology and public health laboratory epidemiology and management. The first cohort of NFELTP residents began their training on 20th October 2008 and completed their training in December 2010. The program was scaled up in 2011 and it admitted 39 residents in its third cohort. The program has admitted residents in six annual cohorts since its inception admitting a total of 207 residents as of 2014 covering all the States. In addition the program has trained 595 health care workers in short courses. Since its inception, the program has responded to 133 suspected outbreaks ranging from environmental related outbreaks, vaccine preventable diseases, water and food borne, zoonoses, (including suspected viral hemorrhagic fevers) as well as neglected tropical diseases. With its emphasis on one health approach of solving public health issues the program has recruited physicians, veterinarians and laboratorians to work jointly on human, animal and environmental health issues. Residents have worked to identify risk factors of disease at the human animal interface for

  4. Training and Service in Public Health, Nigeria Field Epidemiology and Laboratory Training, 2008 – 2014

    PubMed Central

    Nguku, Patrick; Oyemakinde, Akin; Sabitu, Kabir; Olayinka, Adebola; Ajayi, Ikeoluwapo; Fawole, Olufunmilayo; Babirye, Rebecca; Gitta, Sheba; Mukanga, David; Waziri, Ndadilnasiya; Gidado, Saheed; Biya, Oladayo; Gana, Chinyere; Ajumobi, Olufemi; Abubakar, Aisha; Sani-Gwarzo, Nasir; Ngobua, Samuel; Oleribe, Obinna; Poggensee, Gabriele; Nsubuga, Peter; Nyager, Joseph; Nasidi, Abdulsalami

    2014-01-01

    The health workforce is one of the key building blocks for strengthening health systems. There is an alarming shortage of curative and preventive health care workers in developing countries many of which are in Africa. Africa resultantly records appalling health indices as a consequence of endemic and emerging health issues that are exacerbated by a lack of a public health workforce. In low-income countries, efforts to build public health surveillance and response systems have stalled, due in part, to the lack of epidemiologists and well-trained laboratorians. To strengthen public health systems in Africa, especially for disease surveillance and response, a number of countries have adopted a competency-based approach of training - Field Epidemiology and Laboratory Training Program (FELTP). The Nigeria FELTP was established in October 2008 as an inservice training program in field epidemiology, veterinary epidemiology and public health laboratory epidemiology and management. The first cohort of NFELTP residents began their training on 20th October 2008 and completed their training in December 2010. The program was scaled up in 2011 and it admitted 39 residents in its third cohort. The program has admitted residents in six annual cohorts since its inception admitting a total of 207 residents as of 2014 covering all the States. In addition the program has trained 595 health care workers in short courses. Since its inception, the program has responded to 133 suspected outbreaks ranging from environmental related outbreaks, vaccine preventable diseases, water and food borne, zoonoses, (including suspected viral hemorrhagic fevers) as well as neglected tropical diseases. With its emphasis on one health approach of solving public health issues the program has recruited physicians, veterinarians and laboratorians to work jointly on human, animal and environmental health issues. Residents have worked to identify risk factors of disease at the human animal interface for

  5. Intentional injury and violence in Cape Town, South Africa: an epidemiological analysis of trauma admissions data

    PubMed Central

    Schuurman, Nadine; Cinnamon, Jonathan; Walker, Blake Byron; Fawcett, Vanessa; Nicol, Andrew; Hameed, Syed Morad; Matzopoulos, Richard

    2015-01-01

    Background Injury is a truly global health issue that has enormous societal and economic consequences in all countries. Interpersonal violence is now widely recognized as important global public health issues that can be addressed through evidence-based interventions. In South Africa, as in many low- and middle-income countries (LMIC), a lack of ongoing, systematic injury surveillance has limited the ability to characterize the burden of violence-related injury and to develop prevention programmes. Objective To describe the profile of trauma presenting to the trauma centre of Groote Schuur Hospital in Cape Town, South Africa – relating to interpersonal violence, using data collected from a newly implemented surveillance system. Particular emphasis was placed on temporal aspects of injury epidemiology, as well as age and sex differentiation. Design Data were collected prospectively using a standardized trauma admissions form for all patients presenting to the trauma centre. An epidemiological analysis was conducted on 16 months of data collected from June 2010 to October 2011. Results A total of 8445 patients were included in the analysis, in which the majority were violence-related. Specifically, 35% of records included violent trauma and, of those, 75% of victims were male. There was a clear temporal pattern: a greater proportion of intentional injuries occur during the night, while unintentional injury peaks late in the afternoon. In total, two-third of all intentional trauma is inflicted on the weekends, as is 60% of unintentional trauma. Where alcohol was recorded in the record, 72% of cases involved intentional injury. Sex was again a key factor as over 80% of all records involving alcohol or substance abuse were associated with males. The findings highlighted the association between violence, young males, substance use, and weekends. Conclusions This study provides the basis for evidence-based interventions to reduce the burden of intentional injury

  6. Epidemiology of Serotype 1 Invasive Pneumococcal Disease, South Africa, 2003-2013.

    PubMed

    von Mollendorf, Claire; Cohen, Cheryl; Tempia, Stefano; Meiring, Susan; de Gouveia, Linda; Quan, Vanessa; Lengana, Sarona; Karstaedt, Alan; Dawood, Halima; Seetharam, Sharona; Lekalakala, Ruth; Madhi, Shabir A; Klugman, Keith P; von Gottberg, Anne

    2016-02-01

    In South Africa, 7-valent pneumococcal conjugate vaccine (PCV) was introduced in April 2009 and replaced with 13-valent PCV in April 2011. We describe the epidemiology of serotype 1 Streptococcus pneumoniae disease during the pre- and post-PCV eras (2003-2013). Using laboratory-based invasive pneumococcal disease (IPD) surveillance, we calculated annual incidences, identified IPD clusters, and determined serotype 1-associated factors. Of 46,483 IPD cases, 4,544 (10%) were caused by serotype 1. Two clusters of serotype 1 infection were detected during 2003-2004 and 2008-2012, but incidence decreased after 2011. Among children <5 years of age, those who had non-serotype 1 IPD had shorter hospital stays, fewer cases of penicillin-nonsusceptible disease, and lower HIV prevalence and in-hospital death rates than did those with serotype 1 IPD; similar factors were noted for older patients. Serotype 1 IPD had distinctive clinical features in South Africa, and annual incidences fluctuated, with decreases noted after the introduction of PCV13.

  7. Armed conflicts, health and health services in Africa. An epidemiological framework of reference.

    PubMed

    Loretti, A

    1997-01-01

    Because of war, between the 1980s and early '90s Africa suffered about 5 million excess deaths and economic losses estimated at US $13 billion per year. In 1995, war was directly or indirectly affecting 550 million people in 35 countries. Besides violent deaths, injuries and disabilities, displacements of population increase the risk for acute respiratory infections, diarrhoeas, epidemics and parasitic disease. The risk for malnutrition and deficiencies is made worse by the loss of means of production, of food stocks, of commerce and by banditism. Military operations target water plants and health facilities as means of deliberately hurting civilians. Economic crisis curtails the budgets of the social sectors and, together with social distress, undermines national capacities. The delivery of health care is hampered right when hazards and vulnerabilities increase, with general greater risk of illness and death. With the cessation of hostilities, the need for curative and preventative health activities increases and is a matter of emergency, as equitable access to services is important for peace. Repatriation of refugees, demobilization of soldiers and demining require special health activities. War leaves behind new hazards and vulnerabilities such as landmines, wide availability of weapons, artificial concentrations of population, loss of national capacities and psychological disorders. All this interacts tragically with Africa's wider epidemiological realities of poverty, food insecurity, proneness to natural disasters and endemic diseases. PMID:9290329

  8. Epidemiology of Serotype 1 Invasive Pneumococcal Disease, South Africa, 2003–2013

    PubMed Central

    Cohen, Cheryl; Tempia, Stefano; Meiring, Susan; de Gouveia, Linda; Quan, Vanessa; Lengana, Sarona; Karstaedt, Alan; Dawood, Halima; Seetharam, Sharona; Lekalakala, Ruth; Madhi, Shabir A.; Klugman, Keith P.; von Gottberg, Anne

    2016-01-01

    In South Africa, 7-valent pneumococcal conjugate vaccine (PCV) was introduced in April 2009 and replaced with 13-valent PCV in April 2011. We describe the epidemiology of serotype 1 Streptococcus pneumoniae disease during the pre- and post-PCV eras (2003–2013). Using laboratory-based invasive pneumococcal disease (IPD) surveillance, we calculated annual incidences, identified IPD clusters, and determined serotype 1–associated factors. Of 46,483 IPD cases, 4,544 (10%) were caused by serotype 1. Two clusters of serotype 1 infection were detected during 2003–2004 and 2008–2012, but incidence decreased after 2011. Among children <5 years of age, those who had non–serotype 1 IPD had shorter hospital stays, fewer cases of penicillin-nonsusceptible disease, and lower HIV prevalence and in-hospital death rates than did those with serotype 1 IPD; similar factors were noted for older patients. Serotype 1 IPD had distinctive clinical features in South Africa, and annual incidences fluctuated, with decreases noted after the introduction of PCV13. PMID:26812214

  9. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened.

  10. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened. PMID:25929961

  11. Armed conflicts, health and health services in Africa. An epidemiological framework of reference.

    PubMed

    Loretti, A

    1997-01-01

    Because of war, between the 1980s and early '90s Africa suffered about 5 million excess deaths and economic losses estimated at US $13 billion per year. In 1995, war was directly or indirectly affecting 550 million people in 35 countries. Besides violent deaths, injuries and disabilities, displacements of population increase the risk for acute respiratory infections, diarrhoeas, epidemics and parasitic disease. The risk for malnutrition and deficiencies is made worse by the loss of means of production, of food stocks, of commerce and by banditism. Military operations target water plants and health facilities as means of deliberately hurting civilians. Economic crisis curtails the budgets of the social sectors and, together with social distress, undermines national capacities. The delivery of health care is hampered right when hazards and vulnerabilities increase, with general greater risk of illness and death. With the cessation of hostilities, the need for curative and preventative health activities increases and is a matter of emergency, as equitable access to services is important for peace. Repatriation of refugees, demobilization of soldiers and demining require special health activities. War leaves behind new hazards and vulnerabilities such as landmines, wide availability of weapons, artificial concentrations of population, loss of national capacities and psychological disorders. All this interacts tragically with Africa's wider epidemiological realities of poverty, food insecurity, proneness to natural disasters and endemic diseases.

  12. Micronutrient deficiencies. Reports from the field -- Africa.

    PubMed

    Boulet, M

    1997-01-01

    Table salt can now be fortified with iodine and iron without interaction and without loss of potency. According to Levente Diosady, professor of Food Engineering at the University of Toronto, the amounts of the two micronutrients available to the human body have been significantly reduced when the two interacted. In the new technology, the iodine is covered with a dextrin (a water soluble starch) capsule that serves as a physical barrier to the iron. Micronutrient Initiative (an international secretariat based at IDRC that works to eliminate health problems resulting from iron, iodine, and vitamin A deficiencies) and IDRC supported the development of the technology. The efficiency of absorption of the two micronutrients in the new double fortified salt in the human body is being tested at the Hospital for Sick Children in Toronto. Later testing will be conducted by University of Ghana scientists in IDRC-funded trials that will focus on women and their families in areas of Ghana where these deficiencies are endemic. Iodine is part of thyroid hormone, which contributes to brain development in the fetus and regulates human metabolism; iodine deficiency is the most frequent cause of preventable mental retardation. Related disorders include lethargy, physical disabilities, goiter, stillbirth, and neonatal death. Iron deficiency, the most common nutritional problem in the world (particularly among women, infants, and children), is associated with anemia, fatigue, learning problems, pregnancy complications, premature births, and maternal mortality. The two deficiencies together affect more than one-third of the world's population. Approximately 1.6 billion people, in more than 100 countries, live in areas where iodine is not available in sufficient amounts; those most at risk include about one-third of China's population. It is also a severe problem in the Himalayas, the Andes, India, and West Africa.

  13. Extremely low frequency electromagnetic fields and cancer: The epidemiologic evidence

    SciTech Connect

    Bates, M.N. )

    1991-11-01

    This paper reviews the epidemiologic evidence that low frequency electromagnetic fields generated by alternating current may be cause of cancer. Studies examining residential exposures of children and adults and studies of electrical and electronics workers are reviewed. Using conventional epidemiologic criteria for inferring causal associations, including strength and consistency of the relationship, biological plausibility, and the possibility of bias as an explanation, it is concluded that the evidence is strongly suggestive that such radiation is carcinogenic. The evidence is strongest for brain and central nervous system cancers in electrical workers and children. Weaker evidence supports an association with leukemia in electrical workers. Some evidence also exists for an association with melanoma in electrical workers. Failure to find consistent evidence of a link between residential exposures and adult cancers may be attributable to exposure misclassification. Studies so far have used imperfect surrogates for any true biologically effective magnetic field exposure. The resulting exposure misclassification has produced relative risk estimates that understate any true risk.

  14. Proceedings of the African Field Epidemiology Network (AFENET) Scientific Conference 17-22 November 2013 Addis Ababa, Ethiopia: plenaries and oral presentations

    PubMed Central

    Gitta, Sheba Nakacubo; Mwesiga, Allan; Kamadjeu, Raoul

    2015-01-01

    Biennially, trainees and graduates of Field Epidemiology and Laboratory Training Programs (FELTPs) are presented with a platform to share investigations and projects undertaken during their two-year training in Applied Epidemiology. The African Field Epidemiology Network (AFENET) Scientific Conference, is a perfect opportunity for public health professionals from various sectors and organizations to come together to discuss issues that impact on public health in Africa. This year's conference was organized by the Ethiopian Health and Nutrition Research Institute in collaboration with the Ethiopia Ministry of Health, Ethiopian Public Health Association (EPHA), Ethiopia Field Epidemiology Training Program (EFETP), Addis Ababa University (AAU), Training Programs in Epidemiology and Public Health Interventions Network (TEPHINET) and AFENET. Participants at this year's conference numbered 400 from over 20 countries including; Angola, Burkina Faso, Cameroon, Central African Republic, Democratic Republic of the Congo, Ethiopia, Ghana, Indonesia, Kenya, Mozambique, Namibia, Nigeria, Rwanda, South Africa, Sudan, Tanzania, Uganda, Yemen and Zimbabwe. The topics covered in the 144 oral presentations included: global health security, emergency response, public health informatics, vaccine preventable diseases, immunization, outbreak investigation, Millennium Development Goals, Non-Communicable Diseases, and public health surveillance. The theme for the 5th AFENET Scientific Conference was; “Addressing Public Health Priorities in Africa through FELTPs.” Previous AFENET Scientific conferences have been held in: Accra, Ghana (2005), Kampala, Uganda (2007), Mombasa, Kenya (2009) and Dar es Salaam, Tanzania (2011). PMID:26491534

  15. The Epidemiology and Geographic Distribution of Relapsing Fever Borreliosis in West and North Africa, with a Review of the Ornithodoros erraticus Complex (Acari: Ixodida)

    PubMed Central

    Trape, Jean-François; Diatta, Georges; Arnathau, Céline; Bitam, Idir; Sarih, M’hammed; Belghyti, Driss; Bouattour, Ali; Elguero, Eric; Vial, Laurence; Mané, Youssouph; Baldé, Cellou; Pugnolle, Franck; Chauvancy, Gilles; Mahé, Gil; Granjon, Laurent; Duplantier, Jean-Marc

    2013-01-01

    Background Relapsing fever is the most frequent bacterial disease in Africa. Four main vector / pathogen complexes are classically recognized, with the louse Pediculus humanus acting as vector for B. recurrentis and the soft ticks Ornithodoros sonrai, O. erraticus and O. moubata acting as vectors for Borrelia crocidurae, B. hispanica and B. duttonii, respectively. Our aim was to investigate the epidemiology of the disease in West, North and Central Africa. Methods And Findings From 2002 to 2012, we conducted field surveys in 17 African countries and in Spain. We investigated the occurrence of Ornithodoros ticks in rodent burrows in 282 study sites. We collected 1,629 small mammals that may act as reservoir for Borrelia infections. Using molecular methods we studied genetic diversity among Ornithodoros ticks and Borrelia infections in ticks and small mammals. Of 9,870 burrows investigated, 1,196 (12.1%) were inhabited by Ornithodoros ticks. In West Africa, the southern and eastern limits of the vectors and Borrelia infections in ticks and small mammals were 13°N and 01°E, respectively. Molecular studies revealed the occurrence of nine different Ornithodoros species, including five species new for science, with six of them harboring Borrelia infections. Only B. crocidurae was found in West Africa and three Borrelia species were identified in North Africa: B. crocidurae, B. hispanica, and B. merionesi. Conclusions Borrelia Spirochetes responsible for relapsing fever in humans are highly prevalent both in Ornithodoros ticks and small mammals in North and West Africa but Ornithodoros ticks seem absent south of 13°N and small mammals are not infected in these regions. The number of Ornithodoros species acting as vector of relapsing fever is much higher than previously known. PMID:24223812

  16. Bluetongue: a historical and epidemiological perspective with the emphasis on South Africa

    PubMed Central

    2012-01-01

    Bluetongue (BT) is a non-contagious, infectious, arthropod transmitted viral disease of domestic and wild ruminants that is caused by the bluetongue virus (BTV), the prototype member of the Orbivirus genus in the family Reoviridae. Bluetongue was first described in South Africa, where it has probably been endemic in wild ruminants since antiquity. Since its discovery BT has had a major impact on sheep breeders in the country and has therefore been a key focus of research at the Onderstepoort Veterinary Research Institute in Pretoria, South Africa. Several key discoveries were made at this Institute, including the demonstration that the aetiological agent of BT was a dsRNA virus that is transmitted by Culicoides midges and that multiple BTV serotypes circulate in nature. It is currently recognized that BT is endemic throughout most of South Africa and 22 of the 26 known serotypes have been detected in the region. Multiple serotypes circulate each vector season with the occurrence of different serotypes depending largely on herd-immunity. Indigenous sheep breeds, cattle and wild ruminants are frequently infected but rarely demonstrate clinical signs, whereas improved European sheep breeds are most susceptible. The immunization of susceptible sheep remains the most effective and practical control measure against BT. In order to protect sheep against multiple circulating serotypes, three pentavalent attenuated vaccines have been developed. Despite the proven efficacy of these vaccines in protecting sheep against the disease, several disadvantages are associated with their use in the field. PMID:22973992

  17. Sandfly-borne phleboviruses of Eurasia and Africa: epidemiology, genetic diversity, geographic range, control measures.

    PubMed

    Alkan, Cigdem; Bichaud, Laurence; de Lamballerie, Xavier; Alten, Bulent; Gould, Ernest A; Charrel, Rémi N

    2013-10-01

    Sandfly-borne phleboviruses may cause a transient febrile illness (sandfly fever) or more severe neuroinvasive disease. In the Old World, they are vectored by phlebotomine flies, which are widely distributed in the Mediterranean basin, North Africa, the Indian subcontinent, the Middle East and central Asia. High seroprevalence rates have been recorded in humans and domestic animals in areas where sandflies are present. Most published studies have focused on phlebovirus infections of travelers and of soldiers stationed in endemic areas, but the health impact on local populations should not be underestimated, as seroprevalence studies indicate massive circulation of these viruses, even if disease is seldom documented. Except for Toscana virus, which shows a marked neurotropism and is a leading cause of aseptic meningitis in endemic regions, phlebovirus infections are inadequately considered by physicians and are generally underestimated. However, several properties of these viruses suggest that they will extend their geographic range. First, changes in the areas occupied by sandflies as a result of climate change have a direct impact on the epidemiology of associated human and animal diseases. Second, phleboviruses exhibit a high mutation rate, and their tri-segmented genome is prone to reassortment and recombination. Third, distinct virus strains can be transmitted by the same arthropod species. Recent studies have documented the distribution of sandfly-borne phleboviruses in Western Europe, but data for Eastern Europe, the Middle East and Africa are very limited. With the goal of filling knowledge gaps and planning new research programs, we have examined available information and present it as a comprehensive review, with a specific focus on understudied regions. We also discuss the need to conduct studies aimed at developing new antiviral drugs and vaccines.

  18. The Singapore Field Epidemiology Service: Insights Into Outbreak Management

    PubMed Central

    Seetoh, Theresa; Cutter, Jeffery

    2012-01-01

    Field epidemiology involves the implementation of quick and targeted public health interventions with the aid of epidemiological methods. In this article, we share our practical experiences in outbreak management and in safeguarding the population against novel diseases. Given that cities represent the financial nexuses of the global economy, global health security necessitates the safeguard of cities against epidemic diseases. Singapore's public health landscape has undergone a systemic and irreversible shift with global connectivity, rapid urbanization, ecological change, increased affluence, as well as shifting demographic patterns over the past two decades. Concomitantly, the threat of epidemics, ranging from severe acute respiratory syndrome and influenza A (H1N1) to the resurgence of vector-borne diseases as well as the rise of modern lifestyle-related outbreaks, have worsened difficulties in safeguarding public health amidst much elusiveness and unpredictability. One critical factor that has helped the country overcome these innate and man-made public health vulnerabilities is the development of a resilient field epidemiology service, which includes our enhancement of surveillance and response capacities for outbreak management, and investment in public health leadership. We offer herein the Singapore story as a case study in meeting the challenges of disease control in our modern built environment. PMID:23091652

  19. A seismotectonic model from the strain field of Africa

    NASA Astrophysics Data System (ADS)

    Fernandes, Rui; Meghraoui, Mustapha; Radwan, Ali

    2013-04-01

    Using ~100 available permanent GNSS stations we compute a velocity field to obtain the current strain field in Africa. GPS stations with short data span (>2.5 years data span) and monument/equipment instability are excluded for the estimated velocity field. Although significant gaps of geodetic stations still exist, particularly on the Central and North (include Sahara) Africa, the aim is to produce reliable velocity solutions and evaluate the strain velocity field across the African continent with respect to the latest global reference frame (ITRF2008). We consider in our geodetic data analysis the uncertainties related with the temporal correlations between the daily solutions of stations (computed using HECTOR). The geodynamic characteristics of the African plate and its complex sub-plate distribution are better constrained with the increasing number of GNSS permanent stations in Africa (our latest angular velocity model for the three major tectonic units uses a total of 37 solutions: NUBI: 25; SMLA: 07; VICT: 05). The occurrence of recent large intraplate and interplate earthquakes and volcanic activity in Nubia and Somalia combined with the results of geodetic networks contribute to a better constraint of the kinematics along plate boundaries. The comparison between the geodetic strain rate with the seismic strain release along seismically active plate boundaries permit us to observe the existence of zones of localized active deformation with geodetic rate larger than seismic moment rate. Regional studies also show negligible seismic activity in zones with active faults and where the internal plate deformation estimated with geodetic strain fields is significant. This work is prepared in the framework of the IGCP Project 601 - "Seismotectonics and Seismic Hazards in Africa".

  20. Epidemiology of lower respiratory infection and pneumonia in South Africa (1997–2015): a systematic review protocol

    PubMed Central

    Roomaney, Rifqah A; Pillay-van Wyk, Victoria; Awotiwon, Oluwatoyin F; Dhansay, Ali; Groenewald, Pam; Joubert, Jané D; Nglazi, Mweete D; Nicol, Edward; Bradshaw, Debbie

    2016-01-01

    Introduction Lower respiratory infections (LRIs) and pneumonia are among the leading causes of death worldwide, especially in children aged under 5 years, and these patterns are reflected in the South African population. Local epidemiological data for LRIs and pneumonia are required to inform the Second National Burden of Disease Study underway in South Africa. The aim of this systematic review is to identify published studies reporting the prevalence, incidence, case fatality, duration or severity of LRI and pneumonia in adults and children in South Africa. Methods and analysis Electronic database searches will be conducted to obtain studies reporting on the prevalence, incidence, case fatality, duration and severity of LRI and pneumonia in South Africa between January 1997 and December 2015. Studies that are assessed to have moderate or low risk of bias will be included in a meta-analysis, if appropriate. Where meta-analysis is not possible, the articles will be described narratively. Subgroup analysis (eg, age groups) will also be conducted where enough information is available. Ethics and dissemination This systematic review will only include published data with no linked patient-level information; thus, no ethics approval is required. The findings will be used to calculate the burden of disease attributed to LRI and pneumonia in South Africa and will highlight the type of epidemiological data available in the country. The article will be disseminated in a peer-reviewed publication. PROSPERO registration number CRD42016036520. PMID:27633638

  1. Lessons learned from applied field research activities in Africa during the malaria eradication era

    PubMed Central

    Bruce-Chwatt, Leonard J.

    1984-01-01

    The Malaria Conference in Equatorial Africa, convened by the World Health Organization in 1950 in Kampala, Uganda, was a milestone in the history of modern malaria control activities on the continent of Africa. It presented and assessed the available international information on epidemiological aspects of this disease and attempted to coordinate the various methods of research and control of malaria. Its two main recommendations were that malaria should be controlled by all available methods, irrespective of the degree of endemicity of the disease, and that the benefits that malaria control might bring to the indigenous population should be evaluated. The first period of field research and pilot control projects in Africa was between 1950 and 1964. A large number of studies in several African countries showed that the use of residual insecticides such as DDT and HCH might decrease, at times considerably, the amount of malaria transmission, but interruption of transmission could not be achieved, except in two relatively small projects in the forest areas of Cameroon and Liberia. During the second period, from 1965 to 1974, the difficulties of malaria eradication and control in Africa became more evident because of the development of resistance of Anopheles gambiae to DDT, HCH, and dieldrin; moreover administrative, logistic, and financial problems had emerged. It became clear that the prospects for malaria control (let alone those for eradication) were related to the availability of a network of basic health services. A number of “pre-eradication” programmes were set up in order to develop better methods of malaria control and to improve the rural health infrastructures. Much field research on the chemotherapy of malaria was carried out and the value of collective or selective administration of antimalarial drugs was fully recognized, although it became obvious that this could not play an important part in the decrease of transmission of malaria in Africa. The

  2. Epidemiology, health systems and stakeholders in rheumatic heart disease in Africa: a systematic review protocol

    PubMed Central

    Moloi, Annesinah Hlengiwe; Watkins, David; Engel, Mark E; Mall, Sumaya; Zühlke, Liesl

    2016-01-01

    Introduction Rheumatic heart disease (RHD) is a chronic disease affecting the heart valves, secondary to group A streptococcal infection (GAS) and subsequent acute rheumatic fever (ARF). However, RHD cure and preventative measures are inextricably linked with socioeconomic development, as the disease mainly affects children and young adults living in poverty. In order to address RHD, public health officials and health policymakers require up-to-date knowledge on the epidemiology of GAS, ARF and RHD, as well as the existing enablers and gaps in delivery of evidence-based care for these conditions. We propose to conduct a systematic review to assess the literature comprehensively, synthesising all existing quantitative and qualitative data relating to RHD in Africa. Methods and analysis We plan to conduct a comprehensive literature search using a number of databases and reference lists of relevant articles published from January 1995 to December 2015. Two evaluators will independently review and extract data from each article. Additionally, we will assess overall study quality and risk of bias, using the Newcastle-Ottawa Scale and the Critical Appraisal Skills Programme criteria for quantitative and qualitative studies, respectively. We will meta-analyse estimates of prevalence, incidence, case fatality and mortality for each of the conditions separately for each country. Qualitative meta-analysis will be conducted for facilitators and barriers in RHD health access. Lastly, we will create a list of key stakeholders. This protocol is registered in the PROSPERO International Prospective Register of systematic reviews, registration number CRD42016032852. Ethics and dissemination The information provided by this review will inform and assist relevant stakeholders in identifying key areas of intervention, and designing and implementing evidence-based programmes and policies at the local and regional level. With slight modifications (ie, to the country terms in the search

  3. Scorpion envenoming in the north of Mali (West Africa): epidemiological, clinical and therapeutic aspects.

    PubMed

    Dabo, A; Golou, G; Traoré, M S; Diarra, N; Goyffon, M; Doumbo, O

    2011-08-01

    Scorpion envenomation remains a poorly known problem in sub-Saharan Africa, particularly in Mali, where the incidence is high in Northern area of the country (Sahara desert). We conducted a prospective study in two district health centers, Kidal and Tessalit (North-east of Mali), to describe the epidemiological, clinical and therapeutic features of scorpion stings. This study consisted of an exhaustive follow-up from admission to discharge of all patients stung by scorpions. Of a total of 282 cases recorded during one year, 207 (73.4%) occurred in Kidal, and the remaining 75 (26.6%) took place in Tessalit. The annual incidence was significantly higher in Tessalit (437 cases/100,000 population/year) than in Kidal (243 cases/100,000 population/year) (p < 10⁻⁶). Two hundred two (71.6%) stings occurred inside human dwellings, 142 (50.4%) during sleeping/resting, especially in August. One hundred ninety-one (67.7%) were on the lower extremities. Nocturnal stings, 168 (59.6%), occurred more often than diurnal stings, 114 (40.4%). Most patients, 163 (57.8%), were admitted less than 1 h after being stung. Local pain at the sting site was the common primary complaint. However, moderate and severe clinical signs were significantly higher in children than in adults (p < 0.05). The death rate (3.9%) was higher in children (3.5%) than in adults (0.3%) (p = 8.10⁻⁶; RR = 0.90 [IC: 0.84-0.06]). Of the 22 scorpion species identified, 13 (59.1%) were Leiurus quinquestriiatus, 8 (36.4%) were Androctonus amoreuxi, and 1 (4.5%) specimen was Buthiscus bicalcaratus. From these species, L. quinquestriiatus and A. amoreuxi were responsible of stings. The medical treatment was only symptomatic, and one hundred twenty-eight (45.3%) patients received traditional remedies before seeking medical attention. Our findings suggest that scorpion stings are common in the north of Mali and are a significant threat to human health.

  4. Scorpion envenoming in the north of Mali (West Africa): epidemiological, clinical and therapeutic aspects.

    PubMed

    Dabo, A; Golou, G; Traoré, M S; Diarra, N; Goyffon, M; Doumbo, O

    2011-08-01

    Scorpion envenomation remains a poorly known problem in sub-Saharan Africa, particularly in Mali, where the incidence is high in Northern area of the country (Sahara desert). We conducted a prospective study in two district health centers, Kidal and Tessalit (North-east of Mali), to describe the epidemiological, clinical and therapeutic features of scorpion stings. This study consisted of an exhaustive follow-up from admission to discharge of all patients stung by scorpions. Of a total of 282 cases recorded during one year, 207 (73.4%) occurred in Kidal, and the remaining 75 (26.6%) took place in Tessalit. The annual incidence was significantly higher in Tessalit (437 cases/100,000 population/year) than in Kidal (243 cases/100,000 population/year) (p < 10⁻⁶). Two hundred two (71.6%) stings occurred inside human dwellings, 142 (50.4%) during sleeping/resting, especially in August. One hundred ninety-one (67.7%) were on the lower extremities. Nocturnal stings, 168 (59.6%), occurred more often than diurnal stings, 114 (40.4%). Most patients, 163 (57.8%), were admitted less than 1 h after being stung. Local pain at the sting site was the common primary complaint. However, moderate and severe clinical signs were significantly higher in children than in adults (p < 0.05). The death rate (3.9%) was higher in children (3.5%) than in adults (0.3%) (p = 8.10⁻⁶; RR = 0.90 [IC: 0.84-0.06]). Of the 22 scorpion species identified, 13 (59.1%) were Leiurus quinquestriiatus, 8 (36.4%) were Androctonus amoreuxi, and 1 (4.5%) specimen was Buthiscus bicalcaratus. From these species, L. quinquestriiatus and A. amoreuxi were responsible of stings. The medical treatment was only symptomatic, and one hundred twenty-eight (45.3%) patients received traditional remedies before seeking medical attention. Our findings suggest that scorpion stings are common in the north of Mali and are a significant threat to human health. PMID:21605586

  5. Epidemiology and interactions of Human Immunodeficiency Virus – 1 and Schistosoma mansoni in sub-Saharan Africa

    PubMed Central

    2013-01-01

    Human Immunodeficiency Virus-1/AIDS and Schistosoma mansoni are widespread in sub-Saharan Africa and co-infection occurs commonly. Since the early 1990s, it has been suggested that the two infections may interact and potentiate the effects of each other within co-infected human hosts. Indeed, S. mansoni infection has been suggested to be a risk factor for HIV transmission and progression in Africa. If so, it would follow that mass deworming could have beneficial effects on HIV-1 transmission dynamics. The epidemiology of HIV in African countries is changing, shifting from urban to rural areas where the prevalence of Schistosoma mansoni is high and public health services are deficient. On the other side, the consequent pathogenesis of HIV-1/S. mansoni co-infection remains unknown. Here we give an account of the epidemiology of HIV-1 and S. mansoni, discuss co-infection and possible biological causal relationships between the two infections, and the potential impact of praziquantel treatment on HIV-1 viral loads, CD4+ counts and CD4+/CD8+ ratio. Our review of the available literature indicates that there is evidence to support the hypothesis that S. mansoni infections can influence the replication of the HIV-1, cell-to-cell transmission, as well as increase HIV progression as measured by reduced CD4+ T lymphocytes counts. If so, then deworming of HIV positive individuals living in endemic areas may impact on HIV-1 viral loads and CD4+ T lymphocyte counts. PMID:23849678

  6. Louse-borne relapsing fever (Borrelia recurrentis) diagnosed in 15 refugees from northeast Africa: epidemiology and preventive control measures, Bavaria, Germany, July to October 2015.

    PubMed

    Hoch, Martin; Wieser, Andreas; Löscher, Thomas; Margos, Gabriele; Pürner, Friedrich; Zühl, Jürgen; Seilmaier, Michael; Balzer, Lukas; Guggemos, Wolfgang; Rack-Hoch, Anita; von Both, Ulrich; Hauptvogel, Katja; Schönberger, Katharina; Hautmann, Wolfgang; Sing, Andreas; Fingerle, Volker

    2015-01-01

    We report 15 imported louse-borne relapsing fever (LBRF) cases in refugees in Bavaria, Germany. One patient died. Epidemiological findings confirmed that all were young males from the Horn of Africa (12 from Somalia), who had similar migration routes converging in Sudan continuing through Libya and Italy. The majority likely acquired their infection during migration. Healthcare workers should be aware of LBRF in refugees passing through north Africa to ensure correct treatment and preventive measures. PMID:26538532

  7. Louse-borne relapsing fever (Borrelia recurrentis) diagnosed in 15 refugees from northeast Africa: epidemiology and preventive control measures, Bavaria, Germany, July to October 2015.

    PubMed

    Hoch, Martin; Wieser, Andreas; Löscher, Thomas; Margos, Gabriele; Pürner, Friedrich; Zühl, Jürgen; Seilmaier, Michael; Balzer, Lukas; Guggemos, Wolfgang; Rack-Hoch, Anita; von Both, Ulrich; Hauptvogel, Katja; Schönberger, Katharina; Hautmann, Wolfgang; Sing, Andreas; Fingerle, Volker

    2015-01-01

    We report 15 imported louse-borne relapsing fever (LBRF) cases in refugees in Bavaria, Germany. One patient died. Epidemiological findings confirmed that all were young males from the Horn of Africa (12 from Somalia), who had similar migration routes converging in Sudan continuing through Libya and Italy. The majority likely acquired their infection during migration. Healthcare workers should be aware of LBRF in refugees passing through north Africa to ensure correct treatment and preventive measures.

  8. Absence of Putative Artemisinin Resistance Mutations Among Plasmodium falciparum in Sub-Saharan Africa: A Molecular Epidemiologic Study

    PubMed Central

    Taylor, Steve M.; Parobek, Christian M.; DeConti, Derrick K.; Kayentao, Kassoum; Coulibaly, Sheick Oumar; Greenwood, Brian M.; Tagbor, Harry; Williams, John; Bojang, Kalifa; Njie, Fanta; Desai, Meghna; Kariuki, Simon; Gutman, Julie; Mathanga, Don P.; Mårtensson, Andreas; Ngasala, Billy; Conrad, Melissa D.; Rosenthal, Philip J.; Tshefu, Antoinette K.; Moormann, Ann M.; Vulule, John M.; Doumbo, Ogobara K.; ter Kuile, Feiko O.; Meshnick, Steven R.; Bailey, Jeffrey A.; Juliano, Jonathan J.

    2015-01-01

    Plasmodium falciparum parasites that are resistant to artemisinins have been detected in Southeast Asia. Resistance is associated with several polymorphisms in the parasite's K13-propeller gene. The molecular epidemiology of these artemisinin resistance genotypes in African parasite populations is unknown. We developed an assay to quantify rare polymorphisms in parasite populations that uses a pooled deep-sequencing approach to score allele frequencies, validated it by evaluating mixtures of laboratory parasite strains, and then used it to screen P. falciparum parasites from >1100 African infections collected since 2002 from 14 sites across sub-Saharan Africa. We found no mutations in African parasite populations that are associated with artemisinin resistance in Southeast Asian parasites. However, we observed 15 coding mutations, including 12 novel mutations, and limited allele sharing between parasite populations, consistent with a large reservoir of naturally occurring K13-propeller variation. Although polymorphisms associated with artemisinin resistance in P. falciparum in Southeast Asia are not prevalent in sub-Saharan Africa, numerous K13-propeller coding polymorphisms circulate in Africa. Although their distributions do not support a widespread selective sweep for an artemisinin-resistant phenotype, the impact of these mutations on artemisinin susceptibility is unknown and will require further characterization. Rapid, scalable molecular surveillance offers a useful adjunct in tracking and containing artemisinin resistance. PMID:25180240

  9. Absence of putative artemisinin resistance mutations among Plasmodium falciparum in Sub-Saharan Africa: a molecular epidemiologic study.

    PubMed

    Taylor, Steve M; Parobek, Christian M; DeConti, Derrick K; Kayentao, Kassoum; Coulibaly, Sheick Oumar; Greenwood, Brian M; Tagbor, Harry; Williams, John; Bojang, Kalifa; Njie, Fanta; Desai, Meghna; Kariuki, Simon; Gutman, Julie; Mathanga, Don P; Mårtensson, Andreas; Ngasala, Billy; Conrad, Melissa D; Rosenthal, Philip J; Tshefu, Antoinette K; Moormann, Ann M; Vulule, John M; Doumbo, Ogobara K; Ter Kuile, Feiko O; Meshnick, Steven R; Bailey, Jeffrey A; Juliano, Jonathan J

    2015-03-01

    Plasmodium falciparum parasites that are resistant to artemisinins have been detected in Southeast Asia. Resistance is associated with several polymorphisms in the parasite's K13-propeller gene. The molecular epidemiology of these artemisinin resistance genotypes in African parasite populations is unknown. We developed an assay to quantify rare polymorphisms in parasite populations that uses a pooled deep-sequencing approach to score allele frequencies, validated it by evaluating mixtures of laboratory parasite strains, and then used it to screen P. falciparum parasites from >1100 African infections collected since 2002 from 14 sites across sub-Saharan Africa. We found no mutations in African parasite populations that are associated with artemisinin resistance in Southeast Asian parasites. However, we observed 15 coding mutations, including 12 novel mutations, and limited allele sharing between parasite populations, consistent with a large reservoir of naturally occurring K13-propeller variation. Although polymorphisms associated with artemisinin resistance in P. falciparum in Southeast Asia are not prevalent in sub-Saharan Africa, numerous K13-propeller coding polymorphisms circulate in Africa. Although their distributions do not support a widespread selective sweep for an artemisinin-resistant phenotype, the impact of these mutations on artemisinin susceptibility is unknown and will require further characterization. Rapid, scalable molecular surveillance offers a useful adjunct in tracking and containing artemisinin resistance.

  10. Field Test of an Epidemiology Curriculum for Middle School Students

    ERIC Educational Resources Information Center

    Kaelin, Mark A.; Huebner, Wendy W.; Nicolich, Mark J.; Kimbrough, Maudellyn L.

    2007-01-01

    The purpose of this study was to test the effectiveness of a middle school epidemiology curriculum called Detectives in the Classroom. The curriculum presents epidemiology as the science of public health, using health-related issues that capture the interest of young students and help prepare them to make evidence-based health-related decisions.…

  11. Africa.

    ERIC Educational Resources Information Center

    Martz, Carlton

    2001-01-01

    This publication explores issues related to Africa. It examines the U.S. response to the Barbary pirate states (Morocco, Algiers, Tunis, Tripoli) in the early 19th century; the current AIDS crisis in Africa; and 14th century Mali and other Islamic lands through the eyes of Ibn Battuta, who traveled throughout the Muslim world. Each article…

  12. Africa.

    ERIC Educational Resources Information Center

    Happel, Sue; Loeb, Joyce

    Although the activities in this unit are designed primarily for students in the intermediate grades, the document's text, illustrations, and bibliographic references are suitable for anyone interested in learning about Africa. Following a brief introduction and map work, the document is arranged into six sections. Section 1 traces Africa's history…

  13. Molecular epidemiology of Methicillin-resistant Staphylococcus aureus in Africa: a systematic review

    PubMed Central

    Abdulgader, Shima M.; Shittu, Adebayo O.; Nicol, Mark P.; Kaba, Mamadou

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections are a serious global problem, with considerable impact on patients and substantial health care costs. This systematic review provides an overview on the clonal diversity of MRSA, as well as the prevalence of Panton-Valentine leukocidin (PVL)-positive MRSA in Africa. A search on the molecular characterization of MRSA in Africa was conducted by two authors using predefined terms. We screened for articles published in English and French through to October 2014 from five electronic databases. A total of 57 eligible studies were identified. Thirty-four reports from 15 countries provided adequate genotyping data. CC5 is the predominant clonal complex in the healthcare setting in Africa. The hospital-associated MRSA ST239/ST241-III [3A] was identified in nine African countries. This clone was also described with SCCmec type IV [2B] in Algeria and Nigeria, and type V [5C] in Niger. In Africa, the European ST80-IV [2B] clone was limited to Algeria, Egypt and Tunisia. The clonal types ST22-IV [2B], ST36-II [2A], and ST612-IV [2B] were only reported in South Africa. No clear distinctions were observed between MRSA responsible for hospital and community infections. The community clones ST8-IV [2B] and ST88-IV [2B] were reported both in the hospital and community settings in Angola, Cameroon, Gabon, Ghana, Madagascar, Nigeria, and São Tomé and Príncipe. The proportion of PVL-positive MRSA carriage and/or infections ranged from 0.3 to 100% in humans. A number of pandemic clones were identified in Africa. Moreover, some MRSA clones are limited to specific countries or regions. We strongly advocate for more surveillance studies on MRSA in Africa. PMID:25983721

  14. Epidemiologic and Environmental Risk Factors of Rift Valley Fever in Southern Africa from 2008 to 2011

    PubMed Central

    Glancey, Margaret M.; Linthicum, Kenneth J.

    2015-01-01

    Abstract Background: Rift Valley fever (RVF) outbreaks have been associated with periods of widespread and above-normal rainfall over several months. Knowledge on the environmental factors influencing disease transmission dynamics has provided the basis for developing models to predict RVF outbreaks in Africa. From 2008 to 2011, South Africa experienced the worst wave of RVF outbreaks in almost 40 years. We investigated rainfall-associated environmental factors in southern Africa preceding these outbreaks. Methods: RVF epizootic records obtained from the World Animal Health Information Database (WAHID), documenting livestock species affected, location, and time, were analyzed. Environmental variables including rainfall and satellite-derived normalized difference vegetation index (NDVI) data were collected and assessed in outbreak regions to understand the underlying drivers of the outbreaks. Results: The predominant domestic vertebrate species affected in 2008 and 2009 were cattle, when outbreaks were concentrated in the eastern provinces of South Africa. In 2010 and 2011, outbreaks occurred in the interior and southern provinces affecting over 16,000 sheep. The highest number of cases occurred between January and April but epidemics occurred in different regions every year, moving from the northeast of South Africa toward the southwest with each progressing year. The outbreaks showed a pattern of increased rainfall preceding epizootics ranging from 9 to 152 days; however, NDVI and rainfall were less correlated with the start of the outbreaks than has been observed in eastern Africa. Conclusions: Analyses of the multiyear RVF outbreaks of 2008 to 2011 in South Africa indicated that rainfall, NDVI, and other environmental and geographical factors, such as land use, drainage, and topography, play a role in disease emergence. Current and future investigations into these factors will be able to contribute to improving spatial accuracy of models to map risk areas

  15. Epidemiology of lobomycosis-like disease in bottlenose dolphins Tursiops spp. from South America and southern Africa.

    PubMed

    Van Bressem, Marie-Françoise; Simões-Lopes, Paulo C; Félix, Fernando; Kiszka, Jeremy J; Daura-Jorge, Fabio G; Avila, Isabel C; Secchi, Eduardo R; Flach, Leonardo; Fruet, Pedro F; du Toit, Kate; Ott, Paulo H; Elwen, Simon; Di Giacomo, Amanda B; Wagner, Jeanne; Banks, Aaron; Van Waerebeek, Koen

    2015-11-17

    We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere.

  16. Epidemiology of lobomycosis-like disease in bottlenose dolphins Tursiops spp. from South America and southern Africa.

    PubMed

    Van Bressem, Marie-Françoise; Simões-Lopes, Paulo C; Félix, Fernando; Kiszka, Jeremy J; Daura-Jorge, Fabio G; Avila, Isabel C; Secchi, Eduardo R; Flach, Leonardo; Fruet, Pedro F; du Toit, Kate; Ott, Paulo H; Elwen, Simon; Di Giacomo, Amanda B; Wagner, Jeanne; Banks, Aaron; Van Waerebeek, Koen

    2015-11-17

    We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere. PMID:26575156

  17. Heterogeneities of the malaria vectorial system in tropical Africa and their significance in malaria epidemiology and control

    PubMed Central

    Coluzzi, Mario

    1984-01-01

    The most important units of the malaria vectorial system in tropical Africa are included in the Linnaean taxon Anopheles gambiae, which has been split into six sibling species recognized by the application of genetic techniques. More recent studies have shown further complexities involving chromosomal inversion polymorphism in some vector populations as well as incipient speciation processes. The significance for field research in malaria of the splitting of a morphological taxon into genetically defined units and subunits is discussed. PMID:6335681

  18. Field epidemiologic studies of populations exposed to waste dumps.

    PubMed

    Heath, C W

    1983-02-01

    Epidemiologic studies are required for assessing health risks related to toxic waste exposure. Since the settings in which such studies must be performed are extremely diverse, epidemiologic approaches must be versatile. For any particular study, three fundamental requirements are to assess what toxic materials are present, understand how human exposure may occur, and objectively measure possible biologic effects. In assessing links between exposure and disease, epidemiologists must be particularly aware of: expected disease frequencies in relation to the size of populations studied, implications of long or varied disease latencies for study design and competing causes of disease and associated confounding variables. These concepts are illustrated by discussion of epidemiologic studies related to the Love Canal toxic waste dump site in Niagara Falls, NY. PMID:6825633

  19. Rabid epidemiologies: the emergence and resurgence of rabies in twentieth century South Africa.

    PubMed

    Brown, Karen

    2011-01-01

    This article discusses the history of rabies in South Africa since the early twentieth century. It argues that rabies is a zoonotic disease that traverses rural and urban spaces, that transfers itself between wild and domestic animals and remains a potential threat to human life in the region. Scientists discovered an indigenous form of rabies, found primarily in the yellow mongoose, after the first biomedically confirmed human fatalities in 1928. Since the 1950s canine rabies, presumed to have moved southwards from across the Zambezi River, has become endemic also. South Africa is home to a comparatively large number of rabies strains and animal carriers, making it a particularly interesting case study. Environmental changes during the colonial and apartheid periods have helped to explain the increase in rabies cases since the mid-twentieth century. Moreover, developments in the biological and ecological sciences have provided insights into why the rabies virus has become endemic in certain wildlife species.

  20. Africa.

    ERIC Educational Resources Information Center

    Crofts, Marylee

    1986-01-01

    Reviews myths, misconceptions, and unintentional biases about Africa in United States K-12 social studies textbooks. Summarizes common topics and recommends additions. Provides the names, addresses and phone numbers of 10 university-based African Studies centers. Concludes that improvements to textbooks must continue. (JDH)

  1. A Machine Learning Approach to Mapping Agricultural Fields Across Sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Fuchs, T. J.; Thompson, D. R.; Estes, L. D.; Evans, T. P.; Caylor, K. K.

    2013-12-01

    Food production in sub-Saharan Africa is dominated by smallholder agriculture. Rainfed farming practices and the prevailing dryland conditions render crop yields vulnerable to increasing climatic variability. As a result, smallholder farmers are among the poorest and most food insecure groups among the region's population. Quantifying the distribution of smallholder agriculture across sub-Saharan Africa would greatly assist efforts to boost food security. Existing agricultural land cover data sets are limited to estimating the percentage of cropland within a coarse grid cell. The goal of this research is to develop a statistical machine learning algorithm to map individual agricultural fields, mirroring the accuracy of hand-digitization. For the algorithm, a random forest pixel-wise classifier learns by example from training data to distinguish between fields and non-fields. The algorithm then applies this training to classify previously unseen data. These classifications can then be smoothed into coherent regions corresponding to agricultural fields. Our training data set consists of hand-digitized boundaries of agricultural fields in South Africa, commissioned by its government in 2008. Working with 1 km x 1 km scenes across South Africa, the hand-digitized field boundaries are matched with satellite images extracted from Google Maps. To highlight different information contained within the images, several image processing filters are applied. The inclusion of Landsat images for additional training information is also explored. After training and testing the algorithm in South Africa, we aim to expand our mapping efforts across sub-Saharan Africa. Through Princeton's Mapping Africa project, crowdsourcing will produce additional training data sets of hand-digitized field boundaries in new areas of interest. This algorithm and the resulting data sets will provide previously unavailable information at an unprecedented level of detail on the largest and most

  2. Epidemiologic Investigations into Outbreaks of Rift Valley Fever in Humans, South Africa, 2008–2011

    PubMed Central

    Thomas, Juno; Weyer, Jacqueline; Cengimbo, Ayanda; Landoh, Dadja E.; Jacobs, Charlene; Ntuli, Sindile; Modise, Motshabi; Mathonsi, Moshe; Mashishi, Morton S.; Leman, Patricia A.; le Roux, Chantel; Jansen van Vuren, Petrus; Kemp, Alan; Paweska, Janusz T.; Blumberg, Lucille

    2013-01-01

    Rift Valley fever (RVF) is an emerging zoonosis posing a public health threat to humans in Africa. During sporadic RVF outbreaks in 2008–2009 and widespread epidemics in 2010–2011, 302 laboratory-confirmed human infections, including 25 deaths (case-fatality rate, 8%) were identified. Incidence peaked in late summer to early autumn each year, which coincided with incidence rate patterns in livestock. Most case-patients were adults (median age 43 years), men (262; 87%), who worked in farming, animal health or meat-related industries (83%). Most case-patients reported direct contact with animal tissues, blood, or other body fluids before onset of illness (89%); mosquitoes likely played a limited role in transmission of disease to humans. Close partnership with animal health and agriculture sectors allowed early recognition of human cases and appropriate preventive health messaging.

  3. Selected epidemiological aspects of fresh whole blood application in the Polish Field Hospital in Afghanistan.

    PubMed

    Olszewski, Adam; Korzeniewski, Krzysztof; Lass, Anna

    2014-01-01

    Minimisation of blood transmitted diseases is a basic element of all blood transfusion strategies. Civilian health service standards used in peacetime may be difficult to implement in a battlefield. The risk of blood-borne diseases depends on the applied donor qualification procedures and the epidemiological situation in the areas of military operations. The authors discuss various epidemiological aspects considered when selecting potential donors of fresh whole blood for a Walking Blood Bank at the Polish Field Hospital in Afghanistan.

  4. A Sero-epidemiological Study of Arboviral Fevers in Djibouti, Horn of Africa

    PubMed Central

    Andayi, Fred; Charrel, Remi N.; Kieffer, Alexia; Richet, Herve; Pastorino, Boris; Leparc-Goffart, Isabelle; Ahmed, Ammar Abdo; Carrat, Fabrice; Flahault, Antoine; de Lamballerie, Xavier

    2014-01-01

    Arboviral infections have repeatedly been reported in the republic of Djibouti, consistent with the fact that essential vectors for arboviral diseases are endemic in the region. However, there is a limited recent information regarding arbovirus circulation, and the associated risk predictors to human exposure are largely unknown. We performed, from November 2010 to February 2011 in the Djibouti city general population, a cross-sectional ELISA and sero-neutralisation-based sero-epidemiological analysis nested in a household cohort, which investigated the arboviral infection prevalence and risk factors, stratified by their vectors of transmission. Antibodies to dengue virus (21.8%) were the most frequent. Determinants of infection identified by multivariate analysis pointed to sociological and environmental exposure to the bite of Aedes mosquitoes. The population was broadly naïve against Chikungunya (2.6%) with risk factors mostly shared with dengue. The detection of limited virus circulation was followed by a significant Chikungunya outbreak a few months after our study. Antibodies to West Nile virus were infrequent (0.6%), but the distribution of cases faithfully followed previous mapping of infected Culex mosquitoes. The seroprevalence of Rift valley fever virus was 2.2%, and non-arboviral transmission was suggested. Finally, the study indicated the circulation of Toscana-related viruses (3.7%), and a limited number of cases suggested infection by tick-borne encephalitis or Alkhumra related viruses, which deserve further investigations to identify the viruses and vectors implicated. Overall, most of the arboviral cases' predictors were statistically best described by the individuals' housing space and neighborhood environmental characteristics, which correlated with the ecological actors of their respective transmission vectors' survival in the local niche. This study has demonstrated autochthonous arboviral circulations in the republic of Djibouti, and provides

  5. A sero-epidemiological study of arboviral fevers in Djibouti, Horn of Africa.

    PubMed

    Andayi, Fred; Charrel, Remi N; Kieffer, Alexia; Richet, Herve; Pastorino, Boris; Leparc-Goffart, Isabelle; Ahmed, Ammar Abdo; Carrat, Fabrice; Flahault, Antoine; de Lamballerie, Xavier

    2014-12-01

    Arboviral infections have repeatedly been reported in the republic of Djibouti, consistent with the fact that essential vectors for arboviral diseases are endemic in the region. However, there is a limited recent information regarding arbovirus circulation, and the associated risk predictors to human exposure are largely unknown. We performed, from November 2010 to February 2011 in the Djibouti city general population, a cross-sectional ELISA and sero-neutralisation-based sero-epidemiological analysis nested in a household cohort, which investigated the arboviral infection prevalence and risk factors, stratified by their vectors of transmission. Antibodies to dengue virus (21.8%) were the most frequent. Determinants of infection identified by multivariate analysis pointed to sociological and environmental exposure to the bite of Aedes mosquitoes. The population was broadly naïve against Chikungunya (2.6%) with risk factors mostly shared with dengue. The detection of limited virus circulation was followed by a significant Chikungunya outbreak a few months after our study. Antibodies to West Nile virus were infrequent (0.6%), but the distribution of cases faithfully followed previous mapping of infected Culex mosquitoes. The seroprevalence of Rift valley fever virus was 2.2%, and non-arboviral transmission was suggested. Finally, the study indicated the circulation of Toscana-related viruses (3.7%), and a limited number of cases suggested infection by tick-borne encephalitis or Alkhumra related viruses, which deserve further investigations to identify the viruses and vectors implicated. Overall, most of the arboviral cases' predictors were statistically best described by the individuals' housing space and neighborhood environmental characteristics, which correlated with the ecological actors of their respective transmission vectors' survival in the local niche. This study has demonstrated autochthonous arboviral circulations in the republic of Djibouti, and provides

  6. A sero-epidemiological study of arboviral fevers in Djibouti, Horn of Africa.

    PubMed

    Andayi, Fred; Charrel, Remi N; Kieffer, Alexia; Richet, Herve; Pastorino, Boris; Leparc-Goffart, Isabelle; Ahmed, Ammar Abdo; Carrat, Fabrice; Flahault, Antoine; de Lamballerie, Xavier

    2014-12-01

    Arboviral infections have repeatedly been reported in the republic of Djibouti, consistent with the fact that essential vectors for arboviral diseases are endemic in the region. However, there is a limited recent information regarding arbovirus circulation, and the associated risk predictors to human exposure are largely unknown. We performed, from November 2010 to February 2011 in the Djibouti city general population, a cross-sectional ELISA and sero-neutralisation-based sero-epidemiological analysis nested in a household cohort, which investigated the arboviral infection prevalence and risk factors, stratified by their vectors of transmission. Antibodies to dengue virus (21.8%) were the most frequent. Determinants of infection identified by multivariate analysis pointed to sociological and environmental exposure to the bite of Aedes mosquitoes. The population was broadly naïve against Chikungunya (2.6%) with risk factors mostly shared with dengue. The detection of limited virus circulation was followed by a significant Chikungunya outbreak a few months after our study. Antibodies to West Nile virus were infrequent (0.6%), but the distribution of cases faithfully followed previous mapping of infected Culex mosquitoes. The seroprevalence of Rift valley fever virus was 2.2%, and non-arboviral transmission was suggested. Finally, the study indicated the circulation of Toscana-related viruses (3.7%), and a limited number of cases suggested infection by tick-borne encephalitis or Alkhumra related viruses, which deserve further investigations to identify the viruses and vectors implicated. Overall, most of the arboviral cases' predictors were statistically best described by the individuals' housing space and neighborhood environmental characteristics, which correlated with the ecological actors of their respective transmission vectors' survival in the local niche. This study has demonstrated autochthonous arboviral circulations in the republic of Djibouti, and provides

  7. Epidemiology of Hypertension Stages in Two Countries in Sub-Sahara Africa: Factors Associated with Hypertension Stages

    PubMed Central

    Gebreselassie, Kirubel Zemedkun; Padyab, Mojgan

    2015-01-01

    Studies using the revised hypertension classification are needed to better understand epidemiology of hypertension across full distribution. The sociodemographic, biological, and health behavior characteristics associated with different stages of hypertension in Ghana and South Africa (SA) were studied using global ageing and adult health (SAGE), WAVE 1 dataset. Blood pressure was assessed for a total of 7545 respondents, 2980 from SA and 4565 from Ghana. Hypertension was defined using JNC7 blood pressure classification considering previous diagnosis and treatment. Multivariate multinomial logistic regression analysis using Stata version 12 statistical software was done to identify independent predictors. The weighted prevalence of prehypertension and hypertension in Ghana was 30.7% and 42.4%, respectively, and that of SA was 29.4% and 46%, respectively, showing high burden. After adjusting for the independent variables, only age (OR = 1.32, 95% CI: 1.14–1.53), income (OR = 1.9, 95% CI: 1.04–3.47), and BMI (OR = 1.16, 95% CI: 1.1–1.22) remained independent predictors for stage 1 hypertension in Ghana, while, for SA, age (OR = 2.27, 95% CI: 1.53–3.36), sex (OR = 0.28, 95% CI: 0.08–1), and BMI (OR = 1.15, 95% CI: 1.07–1.25) were found to be independent predictors of stage 1 hypertension. Healthy lifestyle changes and policy measures are needed to promptly address these predictors. PMID:26495142

  8. Genetic and epidemiological insights into the emergence of peste des petits ruminants virus (PPRV) across Asia and Africa.

    PubMed

    Padhi, Abinash; Ma, Li

    2014-11-13

    Small ruminants are important components in the livelihood of millions of households in many parts of the world. The spread of the highly contagious peste des petits ruminants (PPR) disease, which is caused by an RNA virus, PPRV, across Asia and Africa remains a major concern. The present study explored the evolutionary and epidemiological dynamics of PPRV through the analyses of partial N-gene and F-gene sequences of the virus. All the four previously described PPRV lineages (I-IV) diverged from their common ancestor during the late-19(th) to early-20(th) century. Among the four lineages, PPRV-IV showed pronounced genetic structuring across the region; however, haplotype sharing among the geographic regions, together with the presence of multiple genetic clusters within a country, indicates the possibility of frequent mobility of the diseased individuals across the region. The gradual decline in the effective number of infections suggests a limited genetic variation, which could be attributed to the effective vaccination that has been practiced since 1990s. However, the movement of infected animals across the region likely contributes to the spread of PPRV-IV. No evidence of positive selection was identified from this study.

  9. Genetic and epidemiological insights into the emergence of peste des petits ruminants virus (PPRV) across Asia and Africa.

    PubMed

    Padhi, Abinash; Ma, Li

    2014-01-01

    Small ruminants are important components in the livelihood of millions of households in many parts of the world. The spread of the highly contagious peste des petits ruminants (PPR) disease, which is caused by an RNA virus, PPRV, across Asia and Africa remains a major concern. The present study explored the evolutionary and epidemiological dynamics of PPRV through the analyses of partial N-gene and F-gene sequences of the virus. All the four previously described PPRV lineages (I-IV) diverged from their common ancestor during the late-19(th) to early-20(th) century. Among the four lineages, PPRV-IV showed pronounced genetic structuring across the region; however, haplotype sharing among the geographic regions, together with the presence of multiple genetic clusters within a country, indicates the possibility of frequent mobility of the diseased individuals across the region. The gradual decline in the effective number of infections suggests a limited genetic variation, which could be attributed to the effective vaccination that has been practiced since 1990s. However, the movement of infected animals across the region likely contributes to the spread of PPRV-IV. No evidence of positive selection was identified from this study. PMID:25391314

  10. Epidemiology of Syphilis in regional blood transfusion centres in Burkina Faso, West Africa

    PubMed Central

    Bisseye, Cyrille; Sanou, Mahamoudou; Nagalo, Bolni Marius; Kiba, Alice; Compaoré, Tegwindé Rebeca; Tao, Issoufou; Simpore, Jacques

    2013-01-01

    Introduction Syphilis remains a major public health problem in sub-Saharan Africa, including Burkina Faso. However, few published data are available on the prevalence of syphilis in the general population. This study had two main objectives: to determine the seroprevalence of syphilis in a cohort of 37,210 first time blood donors and to study socio-demographic factors associated with the risk of infection by Treponema pallidum. Methods Antibodies to Treponema pallidum were screened for, by using Reagin Rapid Test (RPR) and their presence was confirmed by treponema pallidum haemagglutination test (TPHA). Results The overall seroprevalence of syphilis was 1.5% among first time blood donors and was significantly different between centers (p <0.001). The infection was significantly higher in men than women among blood donors in Ouagadougou and Fada N′gourma (P = 0.001 and P = 0.034). The overall seroprevalence of syphilis among blood donors was not associated with either age group or HIV status. In contrast, a significantly high seroprevalence of syphilis was observed in blood donors with HBsAg (P = 0.014) and anti-HCV (P = 0.007) positive. Conclusion Our report shows a low seroprevalence of syphilis in the representative sample of the population of Burkina Faso. The seroprevalence of syphilis remains unequally distributed between urban and rural areas and was not associated with HIV infection. PMID:24711869

  11. The epidemiology of infertility: a review with particular reference to sub-Saharan Africa*

    PubMed Central

    Belsey, Mark A.

    1976-01-01

    The problem of infertility, with particular reference to Africa south of the Sahara, is reviewed. In many areas, up to 40% of women are reported to have completed their reproductive years without bearing a child. The condition is widely distributed, but also often localized in pockets corresponding to geographical or tribal units. Most available demographic data provide estimates of childlessness but it is not sufficient to define the problem in terms of primary and secondary infertility, pregnancy wastage, and infant and child mortality. The major underlying cause for the high levels of infertility appears to be the sequelae of Neisseria gonorrhoeae infection in both men and women, manifested as obstructive azoospermia and tubal occlusion. Other infections, such as those that may follow abortion or delivery, or systemic infections, may be important in some areas. The available data suggest that different patterns of infertility and pregnancy wastage, and different etiological agents and processes, contribute to the problem of infertility in the different areas. The need for a systematic, standardized research approach in several areas is clearly indicated. PMID:798639

  12. Spinocerebellar ataxia type 7 in South Africa: Epidemiology, pathogenesis and therapy.

    PubMed

    Watson, L; Smith, D C; Scholefield, J; Ballo, R; Kidson, S; Greenberg, L J; Wood, M J A

    2016-01-01

    Disorders of the nervous system represent a significant proportion of the global burden of non-communicable diseases, due to the trend towards ageing populations. The Department (now Division) of Human Genetics at the University of Cape Town (UCT) has been involved in pioneering research into these diseases since the appointment of Prof. Peter Beighton as Head of Department in 1972. Beighton's emphasis on understanding the genetic basis of disease laid the groundwork for investigations into several monogenic neurodegenerative conditions, including Huntington's disease and the polyglutamine spinocerebellar ataxias (SCAs). In particular, SCA7, which occurs at an unusually high frequency in the South African (SA) population, was identified as a target for further research and therapeutic development. Beginning with early epidemiological surveys, the SCA7 project progressed to molecular genetics-based investigations, leading to the identification of a founder effect in the SA SCA7 patient population in the mid-2000s. Capitalising on the founder haplotype shared by many SCA7 patients, UCT researchers went on to develop the first population-specific gene-silencing approach for the disease. More recently, efforts have shifted to the development of a more accurate model to decipher the precise mechanisms of neurodegeneration, using induced pluripotent stem cells derived from SA SCA7 patients. In many ways, the SA SCA7 journey reflects the legacy and vision of Prof. Peter Beighton, and his efforts to establish world-class, collaborative research into diseases affecting the African continent. PMID:27245542

  13. Epidemiology of diabetic retinopathy and maculopathy in Africa: a systematic review

    PubMed Central

    Burgess, P I; MacCormick, I J C; Harding, S P; Bastawrous, A; Beare, N A V; Garner, P

    2013-01-01

    Abstract Aim To summarize findings from studies reporting the prevalence and incidence of diabetic retinopathy and diabetic maculopathy in African countries in light of the rising prevalence of diabetes mellitus. Methods Using a predefined search strategy, we systematically searched MEDLINE, EMBASE, Science Citation index and Conference Proceedings Citation index, African Index Medicus and the grey literature database ‘OpenSIGLE’ for studies published between January 1990 and February 2011. Included studies reported prevalence or incidence of diabetic retinopathy or diabetic maculopathy of subjects with diabetes resident in African countries. Results Sixty-two studies from 21 countries were included: three population-based surveys; two cohort studies; five case–control studies; 32 diabetes clinic-based, nine eye clinic-based and 11 other hospital-based surveys. Included studies varied considerably in terms of patient selection, method of assessing the eye and retinopathy classification. In population-based studies, the reported prevalence range in patients with diabetes for diabetic retinopathy was 30.2 to 31.6%, proliferative diabetic retinopathy 0.9 to 1.3%, and any maculopathy 1.2 to 4.5%. In diabetes clinic-based surveys, the reported prevalence range for diabetic retinopathy was 7.0 to 62.4%, proliferative diabetic retinopathy 0 to 6.9%, and any maculopathy 1.2 to 31.1%. No obvious association between prevalence and income level of the country was detected. Conclusions Large, community-based cross-sectional and cohort studies are needed to investigate rates and determinants of prevalence of diabetic retinopathy, incidence and progression in Africa. Consensus is needed on the most appropriate methods of identification and classification of retinopathy for research and clinical practice. Estimates of prevalence of diabetic retinopathy, proliferative diabetic retinopathy and maculopathy are comparable with recent European and American studies. PMID:22817387

  14. Integrating contact network structure into tuberculosis epidemiology in meerkats in South Africa: Implications for control.

    PubMed

    Drewe, Julian A; Eames, Ken T D; Madden, Joah R; Pearce, Gareth P

    2011-08-01

    Empirical studies that integrate information on host contact patterns with infectious disease transmission over time are rare. The aims of this study were to determine the relative importance of intra-group social interactions in the transmission of tuberculosis (TB; Mycobacterium bovis infection) in a population of wild meerkats (Suricata suricatta) in South Africa, and to use this information to propose an evidence-based intervention strategy to manage this disease. Detailed behavioural observations of all members of eight meerkat groups (n=134 individuals) were made over 24 months from January 2006 to December 2007. Social network analysis of three types of interaction (aggression, foraging competitions and grooming) revealed social structure to be very stable over time. Clustering of interactions was positively correlated with group size for both aggression (r=0.73) and grooming interactions (r=0.71), suggesting that infections may spread locally within clusters of interacting individuals but be limited from infecting all members of large groups by an apparent threshold in connections between different clusters. Repeated biological sampling every three months of all members of one social group (n=37 meerkats) was undertaken to quantify individual changes in M. bovis infection status. These empirical data were used to construct a dynamic network model of TB transmission within a meerkat group. The results indicated that grooming (both giving and receiving) was more likely than aggression to be correlated with M. bovis transmission and that groomers were at higher risk of infection than groomees. Intervention strategies for managing TB in meerkats that focus on those individuals engaging in the highest amount of grooming are therefore proposed.

  15. Integrating contact network structure into tuberculosis epidemiology in meerkats in South Africa: Implications for control.

    PubMed

    Drewe, Julian A; Eames, Ken T D; Madden, Joah R; Pearce, Gareth P

    2011-08-01

    Empirical studies that integrate information on host contact patterns with infectious disease transmission over time are rare. The aims of this study were to determine the relative importance of intra-group social interactions in the transmission of tuberculosis (TB; Mycobacterium bovis infection) in a population of wild meerkats (Suricata suricatta) in South Africa, and to use this information to propose an evidence-based intervention strategy to manage this disease. Detailed behavioural observations of all members of eight meerkat groups (n=134 individuals) were made over 24 months from January 2006 to December 2007. Social network analysis of three types of interaction (aggression, foraging competitions and grooming) revealed social structure to be very stable over time. Clustering of interactions was positively correlated with group size for both aggression (r=0.73) and grooming interactions (r=0.71), suggesting that infections may spread locally within clusters of interacting individuals but be limited from infecting all members of large groups by an apparent threshold in connections between different clusters. Repeated biological sampling every three months of all members of one social group (n=37 meerkats) was undertaken to quantify individual changes in M. bovis infection status. These empirical data were used to construct a dynamic network model of TB transmission within a meerkat group. The results indicated that grooming (both giving and receiving) was more likely than aggression to be correlated with M. bovis transmission and that groomers were at higher risk of infection than groomees. Intervention strategies for managing TB in meerkats that focus on those individuals engaging in the highest amount of grooming are therefore proposed. PMID:21683459

  16. Epidemiology of neurodegenerative diseases in sub-Saharan Africa: a systematic review

    PubMed Central

    2014-01-01

    Background Sub-Saharan African (SSA) countries are experiencing rapid transitions with increased life expectancy. As a result the burden of age-related conditions such as neurodegenerative diseases might be increasing. We conducted a systematic review of published studies on common neurodegenerative diseases, and HIV-related neurocognitive impairment in SSA, in order to identify research gaps and inform prevention and control solutions. Methods We searched MEDLINE via PubMed, ‘Banque de Données de Santé Publique’ and the database of the ‘Institut d’Epidemiologie Neurologique et de Neurologie Tropicale’ from inception to February 2013 for published original studies from SSA on neurodegenerative diseases and HIV-related neurocognitive impairment. Screening and data extraction were conducted by two investigators. Bibliographies and citations of eligible studies were investigated. Results In all 144 publications reporting on dementia (n = 49 publications, mainly Alzheimer disease), Parkinsonism (PD, n = 20), HIV-related neurocognitive impairment (n = 47), Huntington disease (HD, n = 19), amyotrophic lateral sclerosis (ALS, n = 15), cerebellar degeneration (n = 4) and Lewy body dementia (n = 1). Of these studies, largely based on prevalent cases from retrospective data on urban populations, half originated from Nigeria and South Africa. The prevalence of dementia (Alzheimer disease) varied between <1% and 10.1% (0.7% and 5.6%) in population-based studies and from <1% to 47.8% in hospital-based studies. Incidence of dementia (Alzheimer disease) ranged from 8.7 to 21.8/1000/year (9.5 to 11.1), and major risk factors were advanced age and female sex. HIV-related neurocognitive impairment’s prevalence (all from hospital-based studies) ranged from <1% to 80%. Population-based prevalence of PD and ALS varied from 10 to 235/100,000, and from 5 to 15/100,000 respectively while that for Huntington disease was 3.5/100,000. Equivalent

  17. The epidemiology of lion lentivirus infection among a population of free-ranging lions (Panthera leo) in the Kruger National Park, South Africa.

    PubMed

    Adams, H; van Vuuren, M; Bosman, A-M; Keet, D; New, J; Kennedy, M

    2009-09-01

    Feline immunodeficiency virus is a lentivirus of domestic cats that causes significant lifelong infection. Infection with this or similar lentiviruses has been detected in several nondomestic feline species, including African lions (Panthera leo). Although lion lentivirus (FIVple) infection is endemic in certain lion populations in eastern and southern Africa, little is known about its pathogenic effects or its epidemiological impact in free-ranging lions. This report describes the epidemiological investigation of lentivirus positivity of free-ranging lions in the Kruger National Park, South Africa. A nested polymerase chain reaction assay for virus detection was performed on all whole blood samples collected. In addition, serum samples were tested for cross-reactive antibodies to domestic feline lentivirus antigens and to puma lentivirus synthetic envelope peptide antigen. The results were analysed in conjunction with epidemiological data to provide a descriptive epidemiological study on lion lentivirus infection in a free-ranging population of lions. The overall prevalence of lentivirus infection was 69%, with a prevalence of 41% in the north of the park, and 80% in the south. Adult males had the highest prevalence when combining the factors of sex and age: 94%. The lowest prevalences were found among juveniles, with male juveniles at 29%. Adults were 5.58 times more likely to test positive for FIVple than juveniles, with adult males being 35 times more likely to be test positive for FIVple compared with juvenile males. This research represents the 1st epidemiological study of the lion lentivirus among free-ranging lions in the Kruger National Park.

  18. Molecular epidemiology of Theileria parva in the field.

    PubMed

    Geysen, D; Bishop, R; Skilton, R; Dolan, T T; Morzaria, S

    1999-09-01

    Molecular tools based on seminested RFLP-PCR techniques to characterize field parasites in bloodspots dried on filter paper permitted investigation of the extent and the dynamics of diversity of Theileria parva populations in the field. Parallel molecular studies explored the long-term genome stability of various isolates by probing Southern blots of EcoRI digested total genomic DNA with four different reference nucleic acid probes. Three polymorphic single copy loci encoding for antigen genes were developed for seminested PCR detection in order to apply them for a multilocus approach in population genetic studies. Seven alleles were identified for the polymorphic immunodominant molecule (PIM) locus by using restriction enzymes, and 4 alleles each for the p150 and p104 loci. A simple DNA extraction method gave good results in amplifying these loci from carrier animals using samples of blood dried on filter papers. Results from probing Southern blots of cultures taken at sequential timepoints indicate relative genome stability in T. parva in comparison to other parasitic protozoa such as Plasmodium. Comparatively homogeneous profiles in sympatric isolates from Zambia were identified using all four probes and PCR amplified products which contrasted with the variety found amongst Kenyan stocks. Preliminary characterization of T. parva field samples from the Southern Province of Zambia strongly suggest clonal expansion of one of the components of a non-Zambian trivalent vaccine used on a limited scale in the Province from 1985 until 1992. PMID:10540308

  19. Building Geophysics Talent and Opportunity in Africa: Experience from the AfricaArray/Wits Geophysics Field School

    NASA Astrophysics Data System (ADS)

    Webb, S. J.; Manzi, M.; Scheiber-Enslin, S. E.; Durrheim, R. J.; Jones, M. Q. W.; Nyblade, A.

    2015-12-01

    There are many challenges faced by geophysics students and academic staff in Africa that make it difficult to develop effective field and research programs. Challenges to conducting field work that have been identified, and that can be tackled are: lack of training on geophysical equipment and lack of exposure to field program design and implementation. To address these challenges, the AfricaArray/Wits Geophysics field school is designed to expose participants to a wide variety of geophysical instruments and the entire workflow of a geophysical project. The AA field school was initially developed for the geophysics students at the University of the Witwatersrand. However, by increasing the number of participants, we are able to make more effective use of a large pool of equipment, while addressing challenging geophysical problems at a remote field site. These additional participants are selected partially based on the likely hood of being able start a field school at their home institution. A good candidate would have access to geophysical equipment, but may not have knowledge of how to use it or how to effectively design surveys. These are frequently junior staff members or graduate students in leadership roles. The three week program introduces participants to the full geophysical field workflow. The first week is spent designing a geophysical survey, including determining the cost. The second week is spent collecting data to address a real geophysical challenge, such as determining overburden thickness, loss of ground features due to dykes in a mine, or finding water. The third week is spent interpreting and integrating the various data sets culminating in a final presentation. Participants are given all lecture material and much of the software is open access; this is done to encourage using the material at the home institution. One innovation has been to use graduate students as instructors, thus building a pool of talent that has developed the logistic and

  20. A brief overview of the history of veterinary field services in South Africa.

    PubMed

    Brückner, Gideon K

    2014-11-14

    The historical evolution of veterinary services in South Africa is closely linked to the colonial history of the past and the eventual political formation of the Union of South Africa in 1910, as well as the establishment of a fully democratic South Africa in 1994. The majority of the early pioneering veterinarians had close links to military activities and were originally mostly of British origin. The appointment of the first colonial chief veterinary officers occurred in the late 1800s. These appointments were dictated by the need to combat devastating animal diseases, such as rinderpest and African horse sickness, mainly because they affected draught oxen (used for travel) and horses (used in combat). Veterinary field services was established in 1962 as a separate functional entity within government services when M.C. Lambrechts became Director of Veterinary Services of South Africa. In the context of this article, veterinary field services refers to that sphere of veterinary service delivery conducted by government-appointed or seconded veterinarians applying disease control and prevention, as required by animal health legislation. Paging through the history of veterinary field services in South Africa confirms that the problems faced by the veterinary services of today were just as real during the times of our pioneers. The pioneers of veterinary services transformed unknown animal diseases into textbook descriptions still used today and also demonstrated the important link to, and use of, the observations made by farmers, as well as the need for continued basic and applied research on animal diseases. This article provided a brief overview of the evolution of veterinary field services and the important role played by pioneers over the last two centuries to make South Africa relatively free and safe from the most important trade-sensitive and economically important animal diseases.

  1. A brief overview of the history of veterinary field services in South Africa.

    PubMed

    Brückner, Gideon K

    2014-01-01

    The historical evolution of veterinary services in South Africa is closely linked to the colonial history of the past and the eventual political formation of the Union of South Africa in 1910, as well as the establishment of a fully democratic South Africa in 1994. The majority of the early pioneering veterinarians had close links to military activities and were originally mostly of British origin. The appointment of the first colonial chief veterinary officers occurred in the late 1800s. These appointments were dictated by the need to combat devastating animal diseases, such as rinderpest and African horse sickness, mainly because they affected draught oxen (used for travel) and horses (used in combat). Veterinary field services was established in 1962 as a separate functional entity within government services when M.C. Lambrechts became Director of Veterinary Services of South Africa. In the context of this article, veterinary field services refers to that sphere of veterinary service delivery conducted by government-appointed or seconded veterinarians applying disease control and prevention, as required by animal health legislation. Paging through the history of veterinary field services in South Africa confirms that the problems faced by the veterinary services of today were just as real during the times of our pioneers. The pioneers of veterinary services transformed unknown animal diseases into textbook descriptions still used today and also demonstrated the important link to, and use of, the observations made by farmers, as well as the need for continued basic and applied research on animal diseases. This article provided a brief overview of the evolution of veterinary field services and the important role played by pioneers over the last two centuries to make South Africa relatively free and safe from the most important trade-sensitive and economically important animal diseases. PMID:25685939

  2. Epidemiology of Leptospirosis in Africa: A Systematic Review of a Neglected Zoonosis and a Paradigm for ‘One Health’ in Africa

    PubMed Central

    Allan, Kathryn J.; Biggs, Holly M.; Halliday, Jo E. B.; Kazwala, Rudovick R.; Maro, Venance P.; Cleaveland, Sarah; Crump, John A.

    2015-01-01

    Background Leptospirosis is an important but neglected bacterial zoonosis that has been largely overlooked in Africa. In this systematic review, we aimed to summarise and compare current knowledge of: (1) the geographic distribution, prevalence, incidence and diversity of acute human leptospirosis in Africa; and (2) the geographic distribution, host range, prevalence and diversity of Leptospira spp. infection in animal hosts in Africa. Methods Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we searched for studies that described (1) acute human leptospirosis and (2) pathogenic Leptospira spp. infection in animals. We performed a literature search using eight international and regional databases for English and non-English articles published between January 1930 to October 2014 that met out pre-defined inclusion criteria and strict case definitions. Results and Discussion We identified 97 studies that described acute human leptospirosis (n = 46) or animal Leptospira infection (n = 51) in 26 African countries. The prevalence of acute human leptospirosis ranged from 2 3% to 19 8% (n = 11) in hospital patients with febrile illness. Incidence estimates were largely restricted to the Indian Ocean islands (3 to 101 cases per 100,000 per year (n = 6)). Data from Tanzania indicate that human disease incidence is also high in mainland Africa (75 to 102 cases per 100,000 per year). Three major species (Leptospira borgpetersenii, L. interrogans and L. kirschneri) are predominant in reports from Africa and isolates from a diverse range of serogroups have been reported in human and animal infections. Cattle appear to be important hosts of a large number of Leptospira serogroups in Africa, but few data are available to allow comparison of Leptospira infection in linked human and animal populations. We advocate a ‘One Health’ approach to promote multidisciplinary research efforts to improve understanding of the animal to human

  3. The Global Epidemiologic Transition: Noncommunicable Diseases and Emerging Health Risk of Allergic Disease in Sub-Saharan Africa

    ERIC Educational Resources Information Center

    Atiim, George A.; Elliott, Susan J.

    2016-01-01

    Globally, there has been a shift in the causes of illness and death from infectious diseases to noncommunicable diseases. This changing pattern has been attributed to the effects of an (ongoing) epidemiologic transition. Although researchers have applied epidemiologic transition theory to questions of global health, there have been relatively few…

  4. [Significance of field epidemiologic study to identification of chronic arsenic poisoning].

    PubMed

    Su, Li-Qin; Jin, Yin-Long

    2005-09-01

    Chronic arsenic poisoning has serious and extensive impact on human health, which attracts wide attention worldwide. Bases on vast public survey, this article introduces recent field studies on chronic arsenic poisoning from three aspects: exposure history, clinical symptoms and laboratory evidences, and also explains the meaning of each index to the determination of chronic arsenic poisoning, then bring forward some considerations on further epidemiological studies on chronic arsenic poisoning. PMID:16329618

  5. [Significance of field epidemiologic study to identification of chronic arsenic poisoning].

    PubMed

    Su, Li-Qin; Jin, Yin-Long

    2005-09-01

    Chronic arsenic poisoning has serious and extensive impact on human health, which attracts wide attention worldwide. Bases on vast public survey, this article introduces recent field studies on chronic arsenic poisoning from three aspects: exposure history, clinical symptoms and laboratory evidences, and also explains the meaning of each index to the determination of chronic arsenic poisoning, then bring forward some considerations on further epidemiological studies on chronic arsenic poisoning.

  6. Prevalence and Trends of Staphylococcus aureus Bacteraemia in Hospitalized Patients in South Africa, 2010 to 2012: Laboratory-Based Surveillance Mapping of Antimicrobial Resistance and Molecular Epidemiology

    PubMed Central

    Perovic, Olga; Iyaloo, Samantha; Kularatne, Ranmini; Lowman, Warren; Bosman, Noma; Wadula, Jeannette; Seetharam, Sharona; Duse, Adriano; Mbelle, Nontombi; Bamford, Colleen; Dawood, Halima; Mahabeer, Yesholata; Bhola, Prathna; Abrahams, Shareef; Singh-Moodley, Ashika

    2015-01-01

    Introduction We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB). Methods Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST). Results S. aureus from 2709 patients were included, and 1231 (46%) were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003). Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001). Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01). The most prevalent SCCmec type was SCCmec type III (531 [41%]) followed by type IV (402 [31%]). Spa-typing discovered 47 different spa-types. The five (87%) most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8) (n = 7) followed by ST5 (CC5) (n = 4), ST36 (CC30) (n = 4) and ST239 (CC8) (n = 3). Conclusions MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41%) and type IV (31%), which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB. PMID:26719975

  7. Reducing the overall HIV-burden in South Africa: is 'reviving ABC' an appropriate fit for a complex, adaptive epidemiological HIV landscape?

    PubMed

    Burman, Christopher J; Aphane, Marota; Delobelle, Peter

    2015-01-01

    This article questions the recommendations to 'revive ABC (abstain, be faithful, condomise)' as a mechanism to 'educate' people in South Africa about HIV prevention as the South African National HIV Prevalence, Incidence and Behaviour Survey, 2012, suggests. We argue that ABC was designed as a response to a particular context which has now radically changed. In South Africa the contemporary context reflects the mass roll-out of antiretroviral treatment; significant bio-medical knowledge gains; a generalised population affected by HIV that has made sense of and embodied those diverse experiences; and a government committed to confronting the epidemic. We suggest that the situation can now be plausibly conceptualised as a complex, adaptive epidemiological landscape that could benefit from an expansion of the existing, 'descriptive' prevention paradigm towards strategies that focus on the dynamics of transmission. We argue for this shift by proposing a theoretical framework based on complexity theory and pattern management. We interrogate one educational prevention heuristic that emphasises the importance of risk-reduction through the lens of transmission, called A-3B-4C-T. We argue that this type of approach provides expansive opportunities for people to engage with the epidemic in contextualised, innovative ways that supersede the opportunities afforded by ABC. We then suggest that framing the prevention imperative through the lens of 'dynamic prevention' at scale opens more immediate opportunities, as well as developing a future-oriented mind-set, than the 'descriptive prevention' parameters can facilitate. The parameters of the 'descriptive prevention' paradigm, that maintain - and partially reinforce - the presence of ABC, do not have the flexibility required to develop the armamentarium of tools required to contribute to the management of a complex epidemiological landscape. Uncritically adhering to both the 'descriptive paradigm', and ABC, represents an

  8. Mapping Agricultural Fields in Sub-Saharan Africa with a Computer Vision Approach

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Luo, D.; Estes, L. D.; Fuchs, T.; Caylor, K. K.

    2014-12-01

    Sub-Saharan Africa is an important focus for food security research, because it is experiencing unprecedented population growth, agricultural activities are largely dominated by smallholder production, and the region is already home to 25% of the world's undernourished. One of the greatest challenges to monitoring and improving food security in this region is obtaining an accurate accounting of the spatial distribution of agriculture. Households are the primary units of agricultural production in smallholder communities and typically rely on small fields of less than 2 hectares. Field sizes are directly related to household crop productivity, management choices, and adoption of new technologies. As population and agriculture expand, it becomes increasingly important to understand both the distribution of field sizes as well as how agricultural communities are spatially embedded in the landscape. In addition, household surveys, a common tool for tracking agricultural productivity in Sub-Saharan Africa, would greatly benefit from spatially explicit accounting of fields. Current gridded land cover data sets do not provide information on individual agricultural fields or the distribution of field sizes. Therefore, we employ cutting edge approaches from the field of computer vision to map fields across Sub-Saharan Africa, including semantic segmentation, discriminative classifiers, and automatic feature selection. Our approach aims to not only improve the binary classification accuracy of cropland, but also to isolate distinct fields, thereby capturing crucial information on size and geometry. Our research focuses on the development of descriptive features across scales to increase the accuracy and geographic range of our computer vision algorithm. Relevant data sets include high-resolution remote sensing imagery and Landsat (30-m) multi-spectral imagery. Training data for field boundaries is derived from hand-digitized data sets as well as crowdsourcing.

  9. A first molecular epidemiological study of SAT-2 type foot-and-mouth disease viruses in West Africa.

    PubMed Central

    Sangaré, O.; Bastos, A. D.; Venter, E. H.; Vosloo, W.

    2004-01-01

    Thirty-one viruses causing SAT-2 outbreaks in seven West African countries between 1974 and 1991, and four viruses representative of East and Central Africa were genetically characterized in this study. Four major viral lineages (I-IV) were identified by phylogenetic analysis of an homologous 480 nucleotide region corresponding to the C-terminus end of VP1. Lineage I comprised two West African genotypes with viruses clustering according to year of isolation rather than geographical origin. Lineage II was represented by viruses isolated between 1979 and 1983 in two neighbouring West African countries, Senegal and The Gambia. Viruses from Nigeria and Eritrea, representative of West and East Africa respectively, constituted lineage III, whilst lineage IV, comprising viruses from Central and East Africa, was regionally and genetically distinct. This study revealed that unrestricted animal movement in West Africa is a major factor in disease dissemination and has also provided the first indication of trans-regional virus transmission. PMID:15188721

  10. Increasing diversity in the geosciences through the AfricaArray geophysics field course

    NASA Astrophysics Data System (ADS)

    Vallejo, G.; Emry, E.; Galindo, B. L.; Carranza, V.; Gomez, C. D.; Ortiz, K.; Castro, J. G.; Guandique, J.; Falzone, C.; Webb, S. J.; Manzi, M.; Mngadi, S. B.; Stephens, K.; Chinamora, B.; Whitehead, R.; de Villiers, D. P.; Tshitlho, K.; Delhaye, R. P.; Smith, J. A.; Nyblade, A.

    2014-12-01

    For the past nine years, the AfricaArray diversity program, sponsored by industry, the National Science Foundation, and several partnering universities have supported outstanding U.S. STEM underrepresented minority undergraduates to gain field experience in near-surface geophysical techniques during an 8-week summer program at Penn State University and the University of Witwatersrand (Wits). The AfricaArray geophysics field school, which is run by Wits, has been teaching field-based geophysics to African students for over a decade. In the first 2-3 weeks of the program, the U.S. students are given basic instruction in near-surface geophysics, South African geology, and South African history and culture. The students then join the Wits AfricaArray geophysics field school - working alongside Wits students and students from several other African universities to map the shallow subsurface in prospective areas of South Africa for platinum mining. In addition to the primary goals of collecting and interpreting gravity, magnetic, resistivity, seismic refraction, seismic reflection, and EM data, students spend time mapping geologic units and gathering information on the physical properties of the rocks in the region (i.e. seismic velocity, density, and magnetic susceptibility). Subsurface targets include mafic dikes, faults, the water table, and overburden thickness. Upon returning to the U.S., students spend 2-3 weeks finalizing their project reports and presentations. The program has been effective at not only providing students with fundamental skills in applied geophysics, but also in fostering multicultural relationships, preparing students for graduate work in the geosciences, and attracting STEM students into the geosciences. Student presenters will discuss their experiences gained through the field school and give their impressions about how the program works towards the goal of increasing diversity in the geosciences in the U.S.

  11. Directional changes of the geomagnetic field in West Africa: Insights from the metallurgical site of Korsimoro

    NASA Astrophysics Data System (ADS)

    Donadini, Fabio; Serneels, Vincent; Kapper, Lisa; El Kateb, Akram

    2015-11-01

    This work shows the first archeomagnetic directions from Western Africa measured on 32 iron smelting kilns dated between 650 and 1800 AD. The archeological excavation of the vast metallurgical site of Korsimoro established the existence of four distinct iron-smelting techniques. The time-frame of each technique could be clearly determined with radiocarbon dating. Many of the kilns investigated in this study could also be dated individually with residual charcoals found in their inside. The results indicate that the inclination of the field changed gradually from shallow normal to shallow reversed during 800 to 1300 AD, and then went back to shallow normal around 1600-1700 AD. The declination was instead stable around 10°E between 800 and 1400 AD, thereafter it started changing towards North. This trend correlates well with available secular variation curves from the Balkan and from Spain, and indicates that the field variation in West Africa was similar to the one in Europe.

  12. Contemporary issues on the epidemiology and antiretroviral adherence of HIV-infected adolescents in sub-Saharan Africa: a narrative review

    PubMed Central

    Adejumo, Olurotimi A; Malee, Kathleen M; Ryscavage, Patrick; Hunter, Scott J; Taiwo, Babafemi O

    2015-01-01

    Introduction Adolescents are a unique and sometimes neglected group in the planning of healthcare services. This is the case in many parts of sub-Saharan Africa, where more than eight out of ten of the world's HIV-infected adolescents live. Although the last decade has seen a reduction in AIDS-related mortality worldwide, largely due to improved access to effective antiretroviral therapy (ART), AIDS remains a significant contributor to adolescent mortality in sub-Saharan Africa. Although inadequate access to ART in parts of the subcontinent may be implicated, research among youth with HIV elsewhere in the world suggests that suboptimal adherence to ART may play a significant role. In this article, we summarize the epidemiology of HIV among sub-Saharan African adolescents and review their adherence to ART, emphasizing the unique challenges and factors associated with adherence behaviour. Methods We conducted a comprehensive search of online databases for articles, relevant abstracts, and conference reports from meetings held between 2010 and 2014. Our search terms included “adherence,” “compliance,” “antiretroviral use” and “antiretroviral adherence,” in combination with “adolescents,” “youth,” “HIV,” “Africa,” “interventions” and the MeSH term “Africa South of the Sahara.” Of 19,537 articles and abstracts identified, 215 met inclusion criteria, and 148 were reviewed. Discussion Adolescents comprise a substantial portion of the population in many sub-Saharan African countries. They are at particular risk of HIV and may experience worse outcomes. Although demonstrated to have unique challenges, there is a dearth of comprehensive health services for adolescents, especially for those with HIV in sub-Saharan Africa. ART adherence is poorer among older adolescents than other age groups, and psychosocial, socio-economic, individual, and treatment-related factors influence adherence behaviour among adolescents in this region. With

  13. Epidemiology and population structure of Staphylococcus aureus in various population groups from a rural and semi urban area in Gabon, Central Africa.

    PubMed

    Ateba Ngoa, Ulysse; Schaumburg, Frieder; Adegnika, Ayola Akim; Kösters, Katrin; Möller, Tina; Fernandes, Jose Francisco; Alabi, Abraham; Issifou, Saadou; Becker, Karsten; Grobusch, Martin Peter; Kremsner, Peter Gottfried; Lell, Bertrand

    2012-10-01

    Little data is available on the epidemiology of Staphylococcus aureus in Africa. In the present study we aim at characterizing the population structure of S. aureus in healthy subjects from a rural and a semi-urban area in Lambaréné, Gabon as well as in hospital staff and inpatients. In total, 500 subjects were screened for S. aureus colonization of the nares, axillae and inguinal region. Overall, 146 (29%) were positive. We found 46 different spa types. The most frequent spa types were t084 (35%) and the agr II was the most prevalent subtype of the accessory gene regulator (56%, n=82). Five isolates (3%) were methicillin resistant S. aureus (MRSA). Carriage rates of S. aureus in Gabon are comparable to developed countries. MRSA is for the first time described and could pose a significant health threat in this region with limited access to microbiological laboratory facilities and to adequate antimicrobial agents.

  14. First archaeomagnetic field intensity data from Ethiopia, Africa (1615 ± 12 AD)

    NASA Astrophysics Data System (ADS)

    Osete, María Luisa; Catanzariti, Gianluca; Chauvin, Annick; Pavón-Carrasco, Francisco Javier; Roperch, Pierrick; Fernández, Víctor M.

    2015-05-01

    First archaeointensity determinations have been obtained from Ethiopia. Seven bricks (34 specimens) from the Däbsan archaeological remains were subjected to archaeointensity determination by means of classical Thellier-Thellier experiment including tests for magnetic anisotropy and magnetic cooling rate dependency. The age of the Däbsan Palace is well controlled by historical information: between 1603, when land grants were conceded to the Jesuits and the Catholicism was established as the official religion in Ethiopia, and the age of the Palace foundation in 1626-27. Successful archaeointensity determinations were obtained in 27 specimens from five individual bricks revealing an average field value of 33.5 ± 1.1 μT, which is 11-26% lower than expected values from global geomagnetic models based on historical and archaeomagnetic data. Global models for 1615 AD predict a low in central-southern Africa related to past location of the present Southern Atlantic Anomaly (SAA). Our results suggest that the field intensity in central Africa may have been slightly lower than global model predictions. This would indicate that the low could be probably more extended towards central-eastern Africa (or more intense) than previously considered. Further data from this region are especially welcome to delineate the evolution of the SAA.

  15. Mental and Substance Use Disorders in Sub-Saharan Africa: Predictions of Epidemiological Changes and Mental Health Workforce Requirements for the Next 40 Years

    PubMed Central

    Charlson, Fiona J.; Diminic, Sandra; Lund, Crick; Degenhardt, Louisa; Whiteford, Harvey A.

    2014-01-01

    The world is undergoing a rapid health transition, with an ageing population and disease burden increasingly defined by disability. In Sub-Saharan Africa the next 40 years are predicted to see reduced mortality, signalling a surge in the impact of chronic diseases. We modelled these epidemiological changes and associated mental health workforce requirements. Years lived with a disability (YLD) predictions for mental and substance use disorders for each decade from 2010 to 2050 for four Sub-Saharan African regions were calculated using Global Burden of Disease 2010 study (GBD 2010) data and UN population forecasts. Predicted mental health workforce requirements for 2010 and 2050, by region and for selected countries, were modelled using GBD 2010 prevalence estimates and recommended packages of care and staffing ratios for low- and middle-income countries, and compared to current staffing from the WHO Mental Health Atlas. Significant population growth and ageing will result in an estimated 130% increase in the burden of mental and substance use disorders in Sub-Saharan Africa by 2050, to 45 million YLDs. As a result, the required mental health workforce will increase by 216,600 full time equivalent staff from 2010 to 2050, and far more compared to the existing workforce. The growth in mental and substance use disorders by 2050 is likely to significantly affect health and productivity in Sub-Saharan Africa. To reduce this burden, packages of care for key mental disorders should be provided through increasing the mental health workforce towards targets outlined in this paper. This requires a shift from current practice in most African countries, involving substantial investment in the training of primary care practitioners, supported by district based mental health specialist teams using a task sharing model that mobilises local community resources, with the expansion of inpatient psychiatric units based in district and regional general hospitals. PMID:25310010

  16. Association between mild cognitive impairment and dementia and undernutrition among elderly people in Central Africa: some results from the EPIDEMCA (Epidemiology of Dementia in Central Africa) programme.

    PubMed

    Pilleron, Sophie; Jésus, Pierre; Desport, Jean-Claude; Mbelesso, Pascal; Ndamba-Bandzouzi, Bébène; Clément, Jean-Pierre; Dartigues, Jean-François; Preux, Pierre-Marie; Guerchet, Maëlenn; Guerchet, Maëlenn; Ndamba-Bandzouzi, Bébène; Mbelesso, Pascal; Pilleron, Sophie; Désormais, Iléana; Lacroix, Philippe; Aboyans, Victor; Desport, Jean-Claude; Jésus, Pierre; Tchalla, Achille; Marin, Benoît; Clément, Jean-Pierre; Lambert, Jean-Charles; Dartigues, Jean-François; Preux, Pierre-Marie

    2015-07-01

    Several studies in Western countries have shown an association between cognitive disorders and low BMI or weight loss in elderly people. However, few data are available in Africa. We analysed the association between cognitive disorders and undernutrition among elderly people in Central Africa. A cross-sectional, multicentre, population-based study using a two-phase design was carried out in subjects aged 65 years and above in the Central African Republic (CAR) and the Republic of Congo (ROC). All subjects were interviewed using the Community Screening Interview for Dementia, and those with low performance were clinically assessed by a neurologist and underwent further psychometrical tests. Diagnostic and Statistical Manual-IV and Petersen's criteria were required for the diagnoses of dementia and mild cognitive impairment (MCI), respectively. Undernutrition was evaluated using mid-upper arm circumference (MUAC) < 24 cm, BMI < 18.5 kg/m(2) and arm muscular circumference (AMC) < 5th percentile. Multivariate binary logistic regression models were used to estimate the associations. In CAR, MCI was associated with MUAC < 24 cm (OR 0.7, 95% CI 0.4, 1.0) and dementia with BMI < 18.5 kg/m(2) (OR 2.3, 95% CI 1.6, 3.1), AMC < 5th percentile (OR 2.3, 95% CI 1.1, 4.6) and MUAC < 24 cm (OR 1.8, 95% CI 1.4, 2.4). In ROC, both MCI and dementia were associated with all markers of undernutrition, but only AMC < 5th percentile was significantly associated with MCI (OR 3.1, 95% CI 1.9, 4.8). In conclusion, cognitive disorders were associated with undernutrition. However, further studies are needed to elucidate the relationship between MCI and undernutrition in CAR.

  17. New constraints on historical dipole field decay: Four centuries of archaeointensity from Cape Town, South Africa.

    NASA Astrophysics Data System (ADS)

    Hare, V. J.; Gallet, Y.; Genevey, A.

    2015-12-01

    Current global geomagnetic field models suffer from strong bias towards Northern Hemisphere data. Absolute intensity measurements from the Southern Hemisphere are key to understanding the evolution of the field over the historical era, especially recent strengthening of non-dipole contributions, and the appearance of the South Atlantic Magnetic Anomaly (SAMA). I present the first archaeointensity data for locally-fired historical bricks from several well-dated sites (1660-2009 AD) in Cape Town, South Africa. These data constitute the first archaeomagnetic intensity variation curve for southern Africa for the past few centuries. The ages of the sites are tightly constrained by historical and archaeological considerations. Archaeointensity data obtained by the Thellier and Thellier method (modified by Coe), are corrected for both TRM anisotropy and cooling rate dependence of TRM acquisition. Analysis of magnetic mineralogy was performed to aid selection of fragments. Reliable archaeointensity determinations were obtained for 48 of 80 specimens, and 45 were retained in the final analysis. Intensity results vary from 24.3 ± 0.6 μT (modern brick) to 40.7 ± 0.8 μT (1660 AD), corresponding to Virtual Axial Dipole Moments (VADMs) between 6.1 ± 0.2 and 10.2 ± 0.2 נ1022 Am2. Results are generally not in agreement with current field models, but are coherent with other archaeomagnetic datasets from the Southern Hemisphere. The possible reasons for this are discussed, as well as implications for the historical evolution of the field.

  18. Laboratory capacity building for the International Health Regulations (IHR[2005]) in resource-poor countries: the experience of the African Field Epidemiology Network (AFENET).

    PubMed

    Masanza, Monica Musenero; Nqobile, Ndlovu; Mukanga, David; Gitta, Sheba Nakacubo

    2010-12-03

    Laboratory is one of the core capacities that countries must develop for the implementation of the International Health Regulations (IHR[2005]) since laboratory services play a major role in all the key processes of detection, assessment, response, notification, and monitoring of events. While developed countries easily adapt their well-organized routine laboratory services, resource-limited countries need considerable capacity building as many gaps still exist. In this paper, we discuss some of the efforts made by the African Field Epidemiology Network (AFENET) in supporting laboratory capacity development in the Africa region. The efforts range from promoting graduate level training programs to building advanced technical, managerial and leadership skills to in-service short course training for peripheral laboratory staff. A number of specific projects focus on external quality assurance, basic laboratory information systems, strengthening laboratory management towards accreditation, equipment calibration, harmonization of training materials, networking and provision of pre-packaged laboratory kits to support outbreak investigation. Available evidence indicates a positive effect of these efforts on laboratory capacity in the region. However, many opportunities exist, especially to support the roll-out of these projects as well as attending to some additional critical areas such as biosafety and biosecuity. We conclude that AFENET's approach of strengthening national and sub-national systems provide a model that could be adopted in resource-limited settings such as sub-Saharan Africa.

  19. Design and implementation of epidemiological field investigation method based on mobile collaboration

    NASA Astrophysics Data System (ADS)

    Zhang, Lihui; Wang, Dongchuan; Huang, Mingxiang; Gong, Jianhua; Fang, Liqun; Cao, Wuchun

    2008-10-01

    With the development of mobile technologies and the integration with the spatial information technologies, it becomes possible to provide a potential to develop new techno-support solutions to Epidemiological Field Investigation especially for the disposal of emergent public health events. Based on mobile technologies and virtual geographic environment, the authors have designed a model for collaborative work in four communication patterns, namely, S2S (Static to Static), M2S (Mobile to Static), S2M (Static to Mobile), and M2M (Mobile to Mobile). Based on the model mentioned above, this paper stresses to explore mobile online mapping regarding mobile collaboration and conducts an experimental case study of HFRS (Hemorrhagic Fever with Renal Syndrome) fieldwork, and then develops a prototype system of emergent response disposition information system to test the effectiveness and usefulness of field survey based on mobile collaboration.

  20. Ionosphere over Africa: Results from Geomagnetic Field Measurements During International Heliophysical Year IHY

    NASA Astrophysics Data System (ADS)

    Rabiu, A. B.; Yumoto, K.; Falayi, E. O.; Bello, O. R.; Magdas/Cpmn Group

    2011-12-01

    Space Environment Research Centre of Kyushu University, Japan, installed 13 units of Magnetic Data Acquisition Systems MAGDAS over Africa during the International Heliophysical Year IHY. Magnetic records from 10 stations along the African 96o Magnetic Meridian (Geographical 30° - 40° East) were examined for Solar quiet daily Sq variations in the two geomagnetic field components H and D. Latitudinal variations of Sq in the geomagnetic components were examined. Signatures of equatorial electrojet and worldwide Sq were identified and studied in detail. H field experienced more variation within the equatorial electrojet zone. Diurnal variations of the geomagnetic variations in the two components were discussed. Sq H is expectedly consistently maximum within the electrojet zone as a result of EEJ. Sq D has maximum values at about -20ɛ (sunrise), -10ɛ (noon time) and +10ɛ (sunset). Levels of inter-relationships between the Sq and its variability in the two components were statistically derived and interpreted in line with the mechanisms responsible for the variations of the geomagnetic field. Data from 2 magnetic observatories within equatorial electrojet EEJ strip and 2 stations outside the EEJ strip were employed to evaluate and study the signatures of the Equatorial electrojet over the African sector. The transient variations of the EEJ at two almost parallel axes using Lagos-Ilorin (West Africa) and Nairobi-Addis Ababa (East Africa) pairs were examined. The eastern electrojet appeared stronger than the western. The latitudinal and longitudinal profiles of the Sq were examined and inferences drawn from observed results were discussed.

  1. Future needs of occupational epidemiology of extremely low frequency electric and magnetic fields: review and recommendations.

    PubMed

    Kheifets, L; Bowman, J D; Checkoway, H; Feychting, M; Harrington, J M; Kavet, R; Marsh, G; Mezei, G; Renew, D C; van Wijngaarden, E

    2009-02-01

    The occupational epidemiological literature on extremely low frequency electric and magnetic fields (EMF) and health encompasses a large number of studies of varying design and quality that have addressed many health outcomes, including various cancers, cardiovascular disease, depression and suicide, and neurodegenerative diseases, such as Alzheimer disease and amyotrophic lateral sclerosis (ALS). At a 2006 workshop we reviewed studies of occupational EMF exposure with an emphasis on methodological weaknesses, and proposed analytical ways to address some of these. We also developed research priorities that we hope will address remaining uncertainties. Broadly speaking, extensive epidemiological research conducted during the past 20 years on occupational EMF exposure does not indicate strong or consistent associations with cancer or any other health outcomes. Inconsistent results for many of the outcomes may be attributable to numerous shortcomings in the studies, most notably in exposure assessment. There is, however, no obvious correlation between exposure assessment quality and observed associations. Nevertheless, for future research, the highest priorities emerge in both the areas of exposure assessment and investigation of ALS. To better assess exposure, we call for the development of a more complete job-exposure matrix that combines job title, work environment and task, and an index of exposure to electric fields, magnetic fields, spark discharge, contact current, and other chemical and physical agents. For ALS, we propose an international collaborative study capable of illuminating a reported association with electrical occupations by disentangling the potential roles of electric shocks, magnetic fields and bias. Such a study will potentially lead to evidence-based measures to protect public health.

  2. One Health concept for strengthening public health surveillance and response through Field Epidemiology and Laboratory Training in Ghana

    PubMed Central

    Wurapa, Frederick; Afari, Ebenezer; Ohuabunwo, Chima; Sackey, Samuel; Clerk, Christine; Kwadje, Simon; Yebuah, Nathaniel; Amankwa, Joseph; Amofah, George; Appiah-Denkyira, Ebenezer

    2011-01-01

    The lack of highly trained field epidemiologists in the public health system in Ghana has been known since the 1970s when the Planning Unit was established in the Ghana Ministry of Health. When the Public Health School was started in 1994, the decision was taken to develop a 1 academic-year general MPH course. The persisting need for well-trained epidemiologists to support the public health surveillance, outbreak investigation and response system made the development of the Field Epidemiology and Laboratory Training Programme (FELTP) a national priority. The School of Public health and the Ministry of Health therefore requested the technical and financial assistance of the United States Centers for Disease Control and Prevention (CDC) in organizing the Programme. The collaboration started by organizing short courses in disease outbreak investigations and response for serving Ghana Health Service staff. The success of the short courses led to development of the FELTP. By October 2007, the new FELTP curriculum for the award of a Masters of Philosophy in Applied Epidemiology and Disease Control was approved by the Academic Board of the University of Ghana and the programme started that academic year. Since then five cohorts of 37 residents have been enrolled in the two tracks of the programme. They consist of 12 physicians, 12 veterinarians and 13 laboratory scientists. The first two cohorts of 13 residents have graduated. The third cohort of seven has submitted dissertations and is awaiting the results. The fourth cohort has started the second year of field placement while the fifth cohort has just started the first semester. The field activities of the graduates have included disease outbreak investigations and response, evaluation of disease surveillance systems at the national level and analysis of datasets on diseases at the regional level. The residents have made a total of 25 oral presentations and 39 poster presentations at various regional and global

  3. One Health concept for strengthening public health surveillance and response through Field Epidemiology and Laboratory Training in Ghana.

    PubMed

    Wurapa, Frederick; Afari, Ebenezer; Ohuabunwo, Chima; Sackey, Samuel; Clerk, Christine; Kwadje, Simon; Yebuah, Nathaniel; Amankwa, Joseph; Amofah, George; Appiah-Denkyira, Ebenezer

    2011-01-01

    The lack of highly trained field epidemiologists in the public health system in Ghana has been known since the 1970s when the Planning Unit was established in the Ghana Ministry of Health. When the Public Health School was started in 1994, the decision was taken to develop a 1 academic-year general MPH course. The persisting need for well-trained epidemiologists to support the public health surveillance, outbreak investigation and response system made the development of the Field Epidemiology and Laboratory Training Programme (FELTP) a national priority. The School of Public health and the Ministry of Health therefore requested the technical and financial assistance of the United States Centers for Disease Control and Prevention (CDC) in organizing the Programme. The collaboration started by organizing short courses in disease outbreak investigations and response for serving Ghana Health Service staff. The success of the short courses led to development of the FELTP. By October 2007, the new FELTP curriculum for the award of a Masters of Philosophy in Applied Epidemiology and Disease Control was approved by the Academic Board of the University of Ghana and the programme started that academic year. Since then five cohorts of 37 residents have been enrolled in the two tracks of the programme. They consist of 12 physicians, 12 veterinarians and 13 laboratory scientists. The first two cohorts of 13 residents have graduated. The third cohort of seven has submitted dissertations and is awaiting the results. The fourth cohort has started the second year of field placement while the fifth cohort has just started the first semester. The field activities of the graduates have included disease outbreak investigations and response, evaluation of disease surveillance systems at the national level and analysis of datasets on diseases at the regional level. The residents have made a total of 25 oral presentations and 39 poster presentations at various regional and global

  4. Molecular Pathologic Epidemiology of Colorectal Neoplasia: An Emerging Transdisciplinary and Interdisciplinary Field

    PubMed Central

    Ogino, Shuji; Chan, Andrew T.; Fuchs, Charles S.; Giovannucci, Edward

    2011-01-01

    Colorectal cancer is a complex disease resulting from somatic genetic and epigenetic alterations, including locus-specific CpG island methylation and global DNA or LINE-1 hypomethylation. Global molecular characteristics such as microsatellite instability (MSI), CpG island methylator phenotype (CIMP), global DNA hypomethylation, and chromosomal instability cause alterations of gene function in a genome-wide scale. Activation of oncogenes including KRAS, BRAF and PIK3CA affects intracellular signaling pathways and has been associated with CIMP and MSI. Traditional epidemiology research has investigated various factors in relation to an overall risk of colon and/or rectal cancer. However, colorectal cancers comprise a heterogeneous group of diseases with different sets of genetic and epigenetic alterations. To better understand how a particular exposure influences the carcinogenic process, somatic molecular changes and tumor biomarkers have been studied in relation to the exposure of interest. Moreover, an investigation of interactive effects of tumor molecular changes and the exposures of interest on tumor behavior (prognosis or clinical outcome) can lead to a better understanding of tumor molecular changes, which may be prognostic or predictive tissue biomarkers. These new research efforts represent “Molecular Pathologic Epidemiology”, which is a multidisciplinary field of investigations of the interrelationship between exogenous and endogenous (e.g., genetic) factors, tumoral molecular signatures and tumor progression. Furthermore, integrating genome-wide association studies (GWAS) with molecular pathologic investigation is a promising area. Examining the relationship between susceptibility alleles identified by GWAS and specific molecular alterations can help elucidate the function of these alleles and provide insights into whether susceptibility alleles are truly causal. Although there are challenges, molecular pathologic epidemiology has unique strengths

  5. Development and Evaluation for Active Learning Instructional Design of Epidemiology in Nursing Informatics Field.

    PubMed

    Majima, Yukie

    2016-01-01

    Nursing education classes are classifiable into three types: lectures, classroom practice, and clinical practice. In this study, we implemented a class that incorporated elements of active learning, including clickers, minutes papers, quizzes, and group work and presentation, in the subject of "epidemiology", which is often positioned in the field of nursing informatics and which is usually taught in conventional knowledge-transmission style lectures, to help students understand knowledge and achieve seven class goals. Results revealed that the average scores of the class achievement (five levels of evaluation) were 3.6-3.9, which was good overall. The highest average score of the evaluation of teaching materials by students (five levels of evaluation) was 4.6 for quizzes, followed by 4.2 for announcement of test statistics, 4.1 for clickers, and 4.0 for news presentation related to epidemiology. We regard these as useful tools for students to increase their motivation. One problem with the class was that it took time to organize the class: creation of tests, class preparation and marking, such as things to be returned and distribution of clickers, and writing comments on small papers. PMID:27332214

  6. Epidemiological typing of Flavimonas oryzihabitans by PCR and pulsed-field gel electrophoresis.

    PubMed

    Liu, P Y; Shi, Z Y; Lau, Y J; Hu, B S; Shyr, J M; Tsai, W S; Lin, Y H; Tseng, C Y

    1996-01-01

    Flavimonas oryzihabitans has emerged as a potential nosocomial pathogen in recent years. The typing method for characterization of this species has never been reported before. Pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus (ERIC)-based PCR were used to generate DNA fingerprints for 14F. oryzihabitans isolates obtained from eight episodes of nosocomial infections during a 2-year period. Both techniques successfully classified these clinical isolates into eight distinct genotypes, thus indicating that all of these episodes of infections were independent. In contrast, repeated isolates from the same patient were assigned to identical genotypes. The reproducibility of both techniques was good. Therefore, we conclude that both PFGE and ERIC-PCR have comparable reproducible and discriminatory powers for the typing of F. oryzihabitans and may be useful for clarifying the epidemiology of this species; however, ERIC-PCR has the advantages of both speed and simplicity.

  7. Epidemiological typing of Flavimonas oryzihabitans by PCR and pulsed-field gel electrophoresis.

    PubMed

    Liu, P Y; Shi, Z Y; Lau, Y J; Hu, B S; Shyr, J M; Tsai, W S; Lin, Y H; Tseng, C Y

    1996-01-01

    Flavimonas oryzihabitans has emerged as a potential nosocomial pathogen in recent years. The typing method for characterization of this species has never been reported before. Pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus (ERIC)-based PCR were used to generate DNA fingerprints for 14F. oryzihabitans isolates obtained from eight episodes of nosocomial infections during a 2-year period. Both techniques successfully classified these clinical isolates into eight distinct genotypes, thus indicating that all of these episodes of infections were independent. In contrast, repeated isolates from the same patient were assigned to identical genotypes. The reproducibility of both techniques was good. Therefore, we conclude that both PFGE and ERIC-PCR have comparable reproducible and discriminatory powers for the typing of F. oryzihabitans and may be useful for clarifying the epidemiology of this species; however, ERIC-PCR has the advantages of both speed and simplicity. PMID:8748275

  8. Epidemiologic studies of electric and magnetic fields and cancer: Strategies for extending knowledge

    SciTech Connect

    Savitz, D.A.

    1993-12-01

    Epidemiologic research concerning electric and magnetic fields in relation to cancer has focused on the potential etiologic roles of residential exposure on childhood cancer and occupational exposure on adult leukemia and brain cancer. Future residential studies must concentrate on exposure assessment that is enhanced by developing models of historical exposure, assessment of the relation between magnetic fields and wire codes, and consideration of alternate exposure indices. Study design issues deserving attention include possible biases in random digit dialing control selection, consideration of the temporal course of exposure and disease, and acquisition of the necessary information to assess the potential value of ecologic studies. Highest priorities are comprehensive evaluation of exposure patterns and sources and examination of the sociology and geography of residential wire codes. Future occupational studies should also concentrate on improved exposure assessment with increased attention to nonutility worker populations and development of historical exposure indicators that are superior to job titles alone. Potential carcinogens in the workplace that could act as confounders need to be more carefully examined. The temporal relation between exposure and disease and possible effect modification by other workplace agents should be incorporated into future studies. The most pressing need is for measurement of exposure patterns in a variety of worker populations and performance of traditional epidemiologic evaluations of cancer occurrence. The principal source of bias toward the null is nondifferential misclassification of exposure with improvements expected to enhance any true etiologic association that is present. Biases away from the null might include biased control selection in residential studies and chemical carcinogens acting as confounders in occupational studies. 51 refs., 1 tab.

  9. Human adverse reproductive outcomes and electromagnetic field exposures: review of epidemiologic studies.

    PubMed Central

    Shaw, G M; Croen, L A

    1993-01-01

    Concerns have been raised regarding a relation between residential and occupational electromagnetic (EM) field exposures and adverse reproductive effects. This paper reviews the epidemiologic evidence for this possible relation, including some pertinent methodologic issues, notes relevant findings from the experimental literature, and discusses areas for future research. Evidence is lacking for a strong association between a woman's use of a video display terminal (VDT) during pregnancy and spontaneous abortion. The evidence for a strong association between a women's use of a VDT and other adverse reproductive endpoints is also lacking, with some suggestive findings for congenital malformations and too few data to reach a conclusion about other endpoints. With respect to low-level EM field exposures other than VDTs, the paucity of data prevents one from determining whether there are reproductive health risks associated with such exposures. Therefore, this is an area that needs further investigation. Given that altered growth may be an underlying biologic effect of EM field exposures, endpoints that might be pursued in future studies include congenital malformations not associated with chromosomal anomalies, intrauterine growth retardation, and chromosomally normal spontaneous abortions. PMID:8206019

  10. Central America Field Epidemiology Training Program (CA FETP): a pathway to sustainable public health capacity development.

    PubMed

    López, Augusto; Cáceres, Victor M

    2008-01-01

    The Central America Field Epidemiology Training Program (CA FETP) is a public health capacity-building training programme aimed at developing high-caliber field epidemiologists at various levels of the public health system. It began in 2000 as part of the effort to rebuild public health infrastructure in six Central American and Caribbean countries following the devastation of Hurricanes Mitch and Georges in late 1998. Since then, the CA FETP has evolved from one regional training programme managed by CDC to several national FETPs with each country assuming ownership of its domestic programme. The curriculum is competency-based, and is divided into a three-tiered training pyramid that corresponds to the needs at the local, district and central levels of the health system. Trainees at each tier spend about 20% of their time in the classroom and 80% in the field implementing what they have learned while being mentored by graduates of the programme. FETP trainees have responded to multiple natural disasters and conducted hundreds of investigations including surveillance evaluations, outbreak responses and planned studies. Also graduates of the CA FETP are assuming influential positions in their respective ministries. As countries meet the challenge of institutionalizing their programmes, the CA FETP concept will increasingly be recognized as a model for sustainable public health capacity development.

  11. Epidemiology of HIV among female sex workers, their clients, men who have sex with men and people who inject drugs in West and Central Africa

    PubMed Central

    Papworth, Erin; Ceesay, Nuha; An, Louis; Thiam-Niangoin, Marguerite; Ky-Zerbo, Odette; Holland, Claire; Dramé, Fatou Maria; Grosso, Ashley; Diouf, Daouda; Baral, Stefan D

    2013-01-01

    Introduction The West and Central Africa (WCA) sub-region is the most populous region of sub-Saharan Africa (SSA), with an estimated population of 356 million living in 24 countries. The HIV epidemic in WCA appears to have distinct dynamics compared to the rest of SSA, being more concentrated among key populations such as female sex workers (FSWs), men who have sex with men (MSM), people who inject drugs (PWID) and clients of FSWs. To explore the epidemiology of HIV in the region, a systematic review of HIV literature among key populations in WCA was conducted since the onset of the HIV epidemic. Methods We searched the databases PubMed, CINAHL and others for peer-reviewed articles regarding FSWs, MSM and PWID in 24 countries with no date restriction. Inclusion criteria were sensitive and focused on inclusion of any HIV prevalence data among key populations. HIV prevalence was pooled, and in each country key themes were extracted from the literature. Results The search generated 885 titles, 214 abstracts and 122 full articles, of which 76 met inclusion and exclusion criteria providing HIV prevalence data. There were 60 articles characterizing the burden of disease among FSWs, eight for their clients, one for both, six for MSM and one for PWID. The pooled HIV prevalence among FSWs was 34.9% (n=14,388/41,270), among their clients was 7.3% (n=435/5986), among MSM was 17.7% (n=656/3714) and among PWID from one study in Nigeria was 3.8% (n=56/1459). Conclusions The disproportionate burden of HIV among FSWs appears to be consistent from the beginning of the HIV epidemic in WCA. While there are less data for other key populations such as clients of FSWs and MSM, the prevalence of HIV is higher among these men compared to other men in the region. There have been sporadic reports among PWID, but limited research on the burden of HIV among these men and women. These data affirm that the HIV epidemic in WCA appears to be far more concentrated among key populations than the

  12. Toward better research practice--shortcomings decreasing the significance of epidemiological studies in the toxicological field.

    PubMed

    Meyer-Baron, Monika; Schäper, Michael; van Thriel, Christoph

    2014-12-01

    Neurobehavioral studies do not always gain the impact they should have, neither in the scientific nor in the regulatory field of neurotoxicology. Among others, shortcomings and inconsistencies across epidemiological studies may contribute to this situation. Examples were compiled to increase awareness of obstacles for conclusions. Meta-analyses were exploited since they sometimes allow the detection of deficits that are not obvious from individual studies. Exposure assessment, performance measures, and confounding were scrutinized among 98 primary studies included in meta-analyses on mercury, solvents, manganese and pesticides. Inconsistent and hardly comparable markers of exposure were found; figures, units or sampling periods were not always provided. The contribution of test materials to differences in test outcomes across studies could sometimes not be evaluated due to the insufficient description of the employed tests. Hypotheses for the selection of performance variables often remained undisclosed. Matching procedures prevailed with respect to the confounder age; the comparability of groups with respect to intelligence and gender remained more elusive. 8% and 16% of the studies did not even mention confounding from intelligence and gender, respectively. Only one third of the studies provided adjusted means for group comparisons; the proportion was slightly larger for studies published 2000-2010. While 50% of the studies considered confounders for their dose-response assessment, only 29% reported results for the total of test variables. The outlined deficits impede, among others, the assessment of exposure-effect relationships and confounding across studies; thereby they limit the use of the studies for toxicological risk assessment and future prevention. Some shortcomings also impede a deeper insight into the mechanisms of toxicity: tests like the Digit Symbol show that something is affected, but not what is affected. Thorough description of measures employed

  13. Aflatoxins and kwashiorkor. Epidemiology and clinical studies in Sudanese children and findings in autopsy liver samples from Nigeria and South Africa.

    PubMed

    Hendrickse, R G; Coulter, J B; Lamplugh, S M; MacFarlane, S B; Williams, T E; Omer, M I; Suliman, G I; El-Zorgani, G A

    1983-11-01

    The aetiology and pathogenesis of kwashiorkor remains obscure. Clinical and epidemiological studies are in progress in Sudan to determine whether aflatoxins play a role in the pathogenesis of kwashiorkor. Local foods are screened for their aflatoxin content and children with kwashiorkor and age and sex matched children with marasmus and with normal nutrition are being investigated for aflatoxins in their blood and urine. Autopsy liver samples of children with kwashiorkor and other nutritional disorders in Nigeria and South Africa have been examined for their aflatoxin content. Aflatoxins are detected using two dimensional thin layer chromatography and high performance liquid chromatography. Results to date on over 350 children studied show that aflatoxins occur more frequently and at higher concentrations in the sera of children with kwashiorkor than in children with marasmus or in normal children. Urinary excretion of aflatoxins in kwashiorkor appears to be less than in other groups. In the autopsy liver samples, aflatoxins have been detected in all kwashiorkor livers but not in livers from marasmic children. These findings seem to implicate aflatoxins in the pathogenesis of kwashiorkor. If this is confirmed it would have very wide implications for the management and prevention of kwashiorkor.

  14. Clear the Mind of Pre-Conceived Ideas and Get Your Hands Dirty! An Approach to Field-Based Courses: The SLUSE-Southern Africa Experience

    ERIC Educational Resources Information Center

    Hill, Trevor R.; Traynor, Catherine H.; Birch-Thomsen, Torben; De Neergaard, Andreas; Bob, Urmilla; Manyatsi, Absalom M.; Sebego, Reuben J.

    2008-01-01

    This paper explores an approach to problem-oriented, interdisciplinary field-based courses devised by university consortia in southern Africa and Denmark. The SLUSE (Sustainable Land Use and Natural Resource Management) model has been applied on six three-week field courses within southern Africa and trained over 200 students. Student groups…

  15. Problems and priorities in epidemiologic research on human health effects related to wiring code and electric and magnetic fields.

    PubMed Central

    Siemiatycki, J

    1993-01-01

    Because of a reported excess of cancers among children living near power lines, there is some concern that electric and magnetic fields (EMFs) induced by electric power sources may affect human health, and this possibility has provoked considerable controversy. The scientific question of whether there are such health effects is far from resolved. Building upon a set of detailed reviews of the available evidence, this paper proposes research priorities and places particular emphasis on epidemiologic research. The most pressing need is to verify the validity of the claim that childhood cancer risk is affected by the type of wiring code in the vicinity of the household. More useful work can be done to verify this in the areas in which such studies have already been carried out, and additional studies should be done elsewhere. Methodological investigation of the interrelationships among different measures and proxies for EMF is needed, and this could feed back to influence the type of EMF measures used in epidemiologic studies. Studies of cancer among adults in relation to EMFs in the work place are needed. Of lower priority are studies of adverse reproductive outcomes in relation to parental EMF exposure and studies of the neurobehavioral impact of chronic EMF exposure. This article also discusses the structural impediments of conducting environmental epidemiology research and argues that bold, large-scale epidemiologic monitoring systems are needed. There is a discussion of the interface between epidemiology and public policy in a topic area as controversial as EMFs. PMID:8206022

  16. Overview of epidemiologic research on electric and magnetic fields and cancer

    SciTech Connect

    Savitz, D.A. )

    1993-04-01

    This overview of epidemiologic research addresses the potential role of 60 Hertz electric and magnetic fields (EMF) in the etiology of cancer. The key findings are summarized with notation of the methodological challenges with which investigators must content. Although exposure is ubiquitous, long-term average EMF is influenced primarily by the background levels in homes, use of selected electric appliances such as electric blankets, and workplace exposures to energized equipment. Studies of residential exposure have focused on childhood cancer, starting with the report of an excess of wire configurations associated with elevated magnetic fields near the homes of children who developed cancer compared to healthy children. Several subsequent studies have tended to confirm that association, although the evidence falls short of demonstrating a causal association between magnetic fields and cancer. Exposures from electric appliances have been less extensively pursued, with some suggestions of an association with childhood cancer. A more extensive literature has evaluated the association between workplace exposure to EMF, based on job titles of electrical workers and cancer. Across many different study designs and settings, certain groups of electrical workers show elevated occurrence of leukemia and brain cancer. The consistency of findings is notable, but the key question is whether the association with job title is due to EMF or some other agent in the workplace. Future research would benefit from specification of testable challenges to a causal association between EMF exposure in the home or workplace and cancer, along with continued efforts to improve our understanding and measurement of EMF exposure. 64 refs.

  17. Disparities in Beef Tapeworm Identification Rates in the Abattoirs of Gauteng Province, South Africa: A Descriptive Epidemiologic Study

    PubMed Central

    Odoi, Agricola

    2016-01-01

    Background Bovine Taenia saginata cysticercus infections (also called bovine cysticercosis or beef measles) is usually diagnosed in cattle only during post-mortem meat inspection. The aim of this study was to investigate the identification rates of these infections in and to identify predictors/determinants of variations in the identification rates in abattoirs in Gauteng province, South Africa. Methods Retrospective data for over 1.4 million cattle carcasses inspected in 26 abattoirs between January 2010 and December 2013 were used for the study. The identification rates (proportion of bovine Taenia saginata cysticercus positive carcasses) were computed and generalized estimating equations used to identify predictors/determinants of identification rates. Results The overall identification rate was 0.70% (95% CI: 0.45, 0.95). Significantly (p< 0.05) lower rates were reported during summer (0.55%) than other seasons. Some geographic areas reported significantly (p<0.05) higher rates than others. The identification rates in high throughput abattoirs was significantly (p<0.05) higher (RR: 9.4; 95% CI: 4.7–19.1) than in low throughput abattoirs. Similarly, the identification rates among animals from feedlots were significantly (p<0.05) higher (RR: 1.6; 95% CI: 1.7–3.5) than those from non-feedlot sources. No significant (p>0.05) association was identified between identification rates and either the number of meat inspectors per abattoir or the provider of inspection services. Conclusion Although no significant association was found between identification rates and provider of inspection services, follow-up studies will need to be done to specifically investigate the potential conflict of interest arising from the fact that abattoir owners hire meat inspection services directly. Capture of abattoir surveillance data needs to include farm address and for each case to be reported separately. Finally, information on the type of identified cysts (alive or calcified

  18. Field epidemiology of an outbreak of dengue fever in Charters Towers, Queensland: are insect screens protective?

    PubMed

    Murray-Smith, S; Weinstein, P; Skelly, C

    1996-10-01

    Between March and July 1993 a dengue virus epidemic swept through Charters Towers, a rural North Queensland mining community of 10,000. This clearly delineated outbreak provided an ideal opportunity to carry out one of the few field epidemiological studies of dengue in Australia. The epicurve was consistent with that of a point source outbreak, 18 weeks in duration and peaking at four weeks. A basic reproduction number for the dengue epidemic of 1.99 indicates a similar rate of spread to that found in dengue epidemics overseas. A female-to-male sex ratio of 1.7:1 was obtained for the 238 cases identified. An age- and sex-matched retrospective case-control study showed that cases were significantly more likely to live in unscreened houses than were controls (McNemar chi 2 = 56.1 df, P < 0.0001). Despite being generally accepted, an association between insect screens and a reduced incidence of mosquito-borne diseases has not previously been demonstrated in Australia. We speculate that unscreened housing facilitates the initial spread of a dengue epidemic.

  19. Ultra-violet radiation is responsible for the differences in global epidemiology of chickenpox and the evolution of varicella-zoster virus as man migrated out of Africa

    PubMed Central

    2011-01-01

    Background Of the eight human herpes viruses, varicella-zoster virus, which causes chickenpox and zoster, has a unique epidemiology. Primary infection is much less common in children in the tropics compared with temperate areas. This results in increased adult susceptibility causing outbreaks, for example in health-care workers migrating from tropical to temperate countries. The recent demonstration that there are different genotypes of varicella-zoster virus and their geographic segregation into tropical and temperate areas suggests a distinct, yet previously unconsidered climatic factor may be responsible for both the clinical and molecular epidemiological features of this virus infection. Presentation of the hypothesis Unlike other human herpes viruses, varicella-zoster virus does not require intimate contact for infection to occur indicating that transmission may be interrupted by a geographically restricted climatic factor. The factor with the largest difference between tropical and temperate zones is ultra-violet radiation. This could reduce the infectiousness of chickenpox cases by inactivating virus in vesicles, before or after rupture. This would explain decreased transmissibility in the tropics and why the peak chickenpox incidence in temperate zones occurs during winter and spring, when ultra-violet radiation is at its lowest. The evolution of geographically restricted genotypes is also explained by ultra-violet radiation driving natural selection of different virus genotypes with varying degrees of resistance to inactivation, tropical genotypes being the most resistant. Consequently, temperate viruses should be more sensitive to its effects. This is supported by the observation that temperate genotypes are found in the tropics only in specific circumstances, namely where ultra-violet radiation has either been excluded or significantly reduced in intensity. Testing the Hypothesis The hypothesis is testable by exposing different virus genotypes to ultra

  20. Aeolian dust emissions in Southern Africa: field measurements of dynamics and drivers

    NASA Astrophysics Data System (ADS)

    Wiggs, Giles; Thomas, David; Washington, Richard; King, James; Eckardt, Frank; Bryant, Robert; Nield, Joanna; Dansie, Andrew; Baddock, Matthew; Haustein, Karsten; Engelstaedter, Sebastian; von Holdt, Johannah; Hipondoka, Martin; Seely, Mary

    2016-04-01

    Airborne dust derived from the world's deserts is a critical component of Earth System behaviour, affecting atmospheric, oceanic, biological, and terrestrial processes as well as human health and activities. However, very few data have been collected on the factors that control dust emission from major source areas, or on the characteristics of the dust that is emitted. Such a paucity of data limits the ability of climate models to properly account for the radiative and dynamical impacts triggered by atmospheric dust. This paper presents field data from the DO4 Models (Dust Observations for Models) project that aims to understand the drivers of variability in dust emission processes from major source areas in southern Africa. Data are presented from three field campaigns undertaken between 2011 and 2015. We analysed remote sensing data to identify the key geomorphological units in southern Africa which are responsible for emission of atmospheric dust. These are the Makgadikgadi pans complex in northern Botswana, the ephemeral river valleys of western Namibia, and Etosha Pan in northern Namibia. Etosha Pan is widely recognised as perhaps the most significant source of atmospheric dust in the southern hemisphere. We deployed an array of field equipment within each source region to measure the variability in and dynamics of aeolian erosivity, as well as dust concentration and flux characteristics. This equipment included up to 11 meteorological stations measuring wind shear stress and other standard climatic parameters, Cimel sun photometers, a LiDAR, sediment transport detectors, high-frequency dust concentration monitors, and dust flux samplers. Further data were gathered at each site on the dynamics of surface characteristics and erodibility parameters that impact upon erosion thresholds. These data were augmented by use of a Pi-Swerl portable wind tunnel. Our data represent the first collected at source for these key dust emission areas and highlight the

  1. Magnetic fields and childhood cancer: an epidemiological investigation of the effects of high-voltage underground cables.

    PubMed

    Bunch, K J; Swanson, J; Vincent, T J; Murphy, M F G

    2015-09-01

    Epidemiological evidence of increased risks for childhood leukaemia from magnetic fields has implicated, as one source of such fields, high-voltage overhead lines. Magnetic fields are not the only factor that varies in their vicinity, complicating interpretation of any associations. Underground cables (UGCs), however, produce magnetic fields but have no other discernible effects in their vicinity. We report here the largest ever epidemiological study of high voltage UGCs, based on 52,525 cases occurring from 1962-2008, with matched birth controls. We calculated the distance of the mother's address at child's birth to the closest 275 or 400 kV ac or high-voltage dc UGC in England and Wales and the resulting magnetic fields. Few people are exposed to magnetic fields from UGCs limiting the statistical power. We found no indications of an association of risk with distance or of trend in risk with increasing magnetic field for leukaemia, and no convincing pattern of risks for any other cancer. Trend estimates for leukaemia as shown by the odds ratio (and 95% confidence interval) per unit increase in exposure were: reciprocal of distance 0.99 (0.95-1.03), magnetic field 1.01 (0.76-1.33). The absence of risk detected in relation to UGCs tends to add to the argument that any risks from overhead lines may not be caused by magnetic fields.

  2. The epidemiology of tuberculosis in free-ranging African buffalo (Syncerus caffer) in the Kruger National Park, South Africa.

    PubMed

    De Vos, V; Bengis, R G; Kriek, N P; Michel, A; Keet, D F; Raath, J P; Huchzermeyer, H F

    2001-06-01

    The presence of bovine tuberculosis (Mycobacterium bovis) in the Kruger National Park (KNP) was determined for the first time in 1990. It was diagnosed in an African buffalo (Syncerus caffer) bull, which was found recumbent and in an emaciated and moribund state near the south-western boundary fence. This prompted an investigation into the bovine tuberculosis (BTB) status of the KNP, with emphasis on its epidemiological determinants and risk factors. This report documents the findings of surveys that were conducted from 1990 to 1996. It was found that BTB had entered the KNP ecosystem relatively recently (+/- 1960), and has found favourable circumstances for survival and propagation in a fully susceptible and immunologically naive buffalo population. Indications are that it entered the KNP from across the southern river boundary, where the presence of infected domestic cattle herds had been documented. From there the infection spread through the southern buffalo population and is currently spreading in a northward direction. It was estimated that this northward spread took place at a rate of about 6 km per year; the prospect being that, if this rate of spread is maintained, the entire KNP may be affected in less than 30 years from now. Spillover from buffalo had already occurred in species such as chacma baboon (Papio ursinus), lion (Panthera leo), cheetah (Acinonyx jubatus), kudu (Tragelaphus strepsiceros) and leopard (Panthera pardus). Although there is no indication yet that these species act as maintenance hosts, the possibility is raised that these, or an as yet overlooked species, might assume such a role in future. In the KNP, BTB manifests itself as a chronic and predominantly subclinical disease in buffalo. It may take years for clinical signs to develop, and then only at a terminal stage, when emaciation is a constant feature. It is suspected that the time from infection to death is variable and dependent on the animal's immune response, which can be

  3. Genotypic diversity in Babesia bovis field isolates and vaccine strains from South Africa.

    PubMed

    Combrink, M P; Troskie, P C; Pienaar, R; Latif, A A; Mans, B J

    2014-01-31

    Genotypic diversity in Babesia bovis (cause of Asiatic redwater in cattle) vaccine strains and field isolates from South Africa were investigated using the Bv80 gene as well as microsatellites. The S11 vaccine strain possessed both A and B alleles of the Bv80 gene, as well as genotypic diversity within each allele type as defined by repeat variation resulting in different amplicon sizes. Rapid serial passage of vaccine strain from passage S10 to S24 resulted in loss of genotypic diversity that yielded a single allele A genotype with an amplicon size of 558 bp. This suggested that clonal selection occurred during rapid passaging. Extensive genotypic diversity exists in 44 field isolates characterized with both Bv80 A and B alleles, but can be readily distinguished from the S24 vaccine strain using either the Bv80 allele specific PCR assays or using multi-locus micro-satellite typing. This indicated that no recent documented clinical cases of Asiatic redwater were caused by the reversion to virulence of the current vaccine strain.

  4. Geopotential field anomalies and regional tectonic features - two case studies: southern Africa and Germany

    NASA Astrophysics Data System (ADS)

    Korte, Monika; Mandea, Mioara

    2016-05-01

    Maps of magnetic and gravity field anomalies provide information about physical properties of the Earth's crust and upper mantle, helpful in understanding geological conditions and tectonic structures. Depending on data availability, whether from the ground, airborne, or from satellites, potential field anomaly maps contain information on different ranges of spatial wavelengths, roughly corresponding to sources at different depths. Focussing on magnetic data, we compare amplitudes and characteristics of anomalies from maps based on various available data and as measured at geomagnetic repeat stations. Two cases are investigated: southern Africa, characterized by geologically old cratons and strong magnetic anomalies, and the smaller region of Germany with much younger crust and weaker anomalies. Estimating lithospheric magnetic anomaly values from the ground stations' time series (repeat station crustal biases) reveals magnetospheric field contributions causing time-varying offsets of several nT in the results. Similar influences might be one source of discrepancy when merging anomaly maps from different epochs. Moreover, we take advantage of recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of ˜ 200 km resolution. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Comparing short- and long-wavelength anomalies and the correlation of rather large-scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement in the southern African region than the German region. This probably indicates stronger concordance between near-surface (down to at most a few km) and deeper (several kilometres down to Curie depth) structures in the former area, which can be seen to agree with a thicker lithosphere and a lower heat flux reported in the literature for the southern

  5. Improving Agricultural Drought Monitoring in East Africa with Unbiased Rainfall Fields and Detailed Land Surface Physics

    NASA Astrophysics Data System (ADS)

    McNally, A.; Yatheendradas, S.; Peters-Lidard, C. D.; Michaelsen, J.

    2010-12-01

    Monitoring drought is particularly challenging within rainfed agricultural and pastoral systems, where it can serve the greatest need. Such locations often have sparse or non-existent ground based measurements of precipitation, evapotranspiration (ET), and soil moisture. For more effective drought monitoring with limited hydroclimate observations, we simulate land surface states using the Community Noah Land Surface Model forced with different merged rainfall products inside a Land Information System (LIS). Using model outputs we will answer the questions: How sensitive are soil moisture and ET fields to differences in rainfall forcing and model physics? What are acceptable drought-specific tradeoffs between near-real time availability and skill of rainfall data? Preliminary results with the African Rainfall Estimation Algorithm Version 2 (RFE2.0) outperformed global products, suggesting that sub-global rainfall estimates are the way forward for regional drought monitoring. Specifically, the Noah model forced with RFE2.0 better resolved the heterogeneous patterns in crop stress than the Famine Early Warning System Network (FEWS NET) operational Water Requirement Satisfaction Index (WRSI) model. To further investigate the improvement in drought monitoring while maintaining timeliness, we unbias (using Africa specific climatology) the precipitation products from CPC Merged Analysis of Precipitation (CMAP), Tropical Rainfall Measurement Mission (TRMM), and RFE2.0. The skill (relative accuracy) and reliability (average agreement) of the unbiased rainfall are calculated against an unbiased precipitation product augmented with station data from Ethiopia and Kenya. Soil moisture and ET fields from Noah are compared to the operational FEWS NET WRSI, soil water anomaly index, and the World Food Program’s Crop and Food Security Assessment Mission reports. We anticipate that the unbiased rainfall fields will improve the accuracy, spatio-temporal resolution, and

  6. 3D airflow dynamics over transverse ridges Mpekweni, South Africa: implications for dune field migration behaviour

    NASA Astrophysics Data System (ADS)

    Jackson, Derek; Cooper, Andrew; Green, Andrew; Beyers, Meiring; Wiles, Errol; Benallack, Keegan

    2016-04-01

    Un-vegetated dune fields provide excellent opportunities to examine airflow dynamics over various types and scales of dune landforms. The three dimensional surface over which lower boundary layers travel, help adjust surface airflow and consequently the aeolian response of the dunes themselves. The use of computational fluid dynamic (CFD) modelling in recent studies now enables investigation of the 3D behaviour of airflow over complex terrain, providing new insights into heterogeneous surface flow and aeolian response of dune surfaces on a large (dunefield) scale. Using a largely un-vegetated coastal dune field site at Mpekweni, Eastern Cape, South Africa, a detailed (0.1m gridded) terrestrial laser scanning survey was conducted to create a high resolution topographical surface. Using local wind flow measurements and local met station records as input, CFD modelling was performed for a number of scenarios involving variable direction and magnitude to examine surface flow patterns across multiple dune forms. Near surface acceleration, expansion and separation of airflow inducing convergence and divergence (steering) of flow velocity streamlines are investigated. Flow acceleration over dune crests/brink lines is a key parameter in driving dune migration and slip face dynamics. Dune aspect ratio (height to length) is also important in determining the degree of crestal flow acceleration, with an increase in flow associated with increasing aspect ratios. Variations in dune height appear to be the most important parameter in driving general flow acceleration. The results from the study provide new insights into dune migration behaviour at this site as well as surface flow behaviour across multiple dune configurations and length scales within un-vegetated dune fields.

  7. Molecular Epidemiology of Mycobacterium tuberculosis Isolates in 100 Patients With Tuberculosis Using Pulsed Field Gel Electrophoresis

    PubMed Central

    Pooideh, Mohammad; Jabbarzadeh, Ismail; Ranjbar, Reza; Saifi, Mahnaz

    2015-01-01

    Background: Tuberculosis (TB) is a widespread infectious disease. Today, TB has created a public health crisis in the world. Genotyping of Mycobacterium tuberculosis isolates is useful for surveying the dynamics of TB infection, identifying new outbreaks, and preventing the disease. Different molecular methods for clustering of M. tuberculosis isolates have been used. Objectives: During a one year study of genotyping, 100 M. tuberculosis isolates from patients referred to Pasteur Institute of Iran were collected and their genotyping was accomplished using pulsed field gel electrophoresis (PFGE) method. Materials and Methods: Identification of all M. tuberculosis isolates was accomplished using standard biochemical and species-specific polymerase chain reaction (PCR) methods. Antibiotic susceptibility tests were performed using proportional method. After preparing PFGE plaques for each isolate of M. tuberculosis, XbaI restriction enzyme was applied for genome digestion. Finally, the digested DNA fragments were separated on 1% agarose gel and analyzed with GelCompar II software. Results: Genotyping of the studied isolates in comparison with the molecular weight marker revealed two common types; pulsotype A with 71 isolates and one multidrug resistant mycobacterium (MDR) case, and pulsotype B including 29 isolates and three MDR cases. No correlation between the antibiotypes and pulsotypes was observed. Conclusions: Molecular epidemiology studies of infectious diseases have been useful when bacterial isolates have been clustered in a period of time and in different geographical regions with variable antibiotic resistance patterns. In spite of high geographical differences and different antibiotic resistant patterns, low genetic diversity among the studied TB isolates may refer to the low rate of mutations in XbaI restriction sites in the mycobacterial genome. We also identified three MDR isolates in low-incidence pulsotype B, which could be disseminated and is highly

  8. How to make epidemiological training infectious.

    PubMed

    Bellan, Steve E; Pulliam, Juliet R C; Scott, James C; Dushoff, Jonathan

    2012-01-01

    Modern infectious disease epidemiology builds on two independently developed fields: classical epidemiology and dynamical epidemiology. Over the past decade, integration of the two fields has increased in research practice, but training options within the fields remain distinct with few opportunities for integration in the classroom. The annual Clinic on the Meaningful Modeling of Epidemiological Data (MMED) at the African Institute for Mathematical Sciences has begun to address this gap. MMED offers participants exposure to a broad range of concepts and techniques from both epidemiological traditions. During MMED 2010 we developed a pedagogical approach that bridges the traditional distinction between classical and dynamical epidemiology and can be used at multiple educational levels, from high school to graduate level courses. The approach is hands-on, consisting of a real-time simulation of a stochastic outbreak in course participants, including realistic data reporting, followed by a variety of mathematical and statistical analyses, stemming from both epidemiological traditions. During the exercise, dynamical epidemiologists developed empirical skills such as study design and learned concepts of bias while classical epidemiologists were trained in systems thinking and began to understand epidemics as dynamic nonlinear processes. We believe this type of integrated educational tool will prove extremely valuable in the training of future infectious disease epidemiologists. We also believe that such interdisciplinary training will be critical for local capacity building in analytical epidemiology as Africa continues to produce new cohorts of well-trained mathematicians, statisticians, and scientists. And because the lessons draw on skills and concepts from many fields in biology--from pathogen biology, evolutionary dynamics of host--pathogen interactions, and the ecology of infectious disease to bioinformatics, computational biology, and statistics--this exercise

  9. Spatial variability of solar quiet fields along 96° magnetic meridian in Africa: Results from MAGDAS

    NASA Astrophysics Data System (ADS)

    Bolaji, O. S.; Rabiu, A. B.; Bello, O. R.; Yoshikawa, A.; Yumoto, K.; Odeyemi, O. O.; Ogunmodimu, O.

    2015-05-01

    We have used chains of Magnetic Data Acquisition System (MAGDAS) magnetometer records of the horizontal (H) and vertical (Z) magnetic field intensities during September 2008 to August 2009 (year of deep minimum) across Africa to study their variability during the quietest international days, which coincidently associated with the sudden stratospheric warming (SSW) event in January 2009. This selection of the most international quiet days is indicative of 80% that are strongly associated with days when unusually strong and prolonged sudden SSW event occurs in January 2009. Interestingly, in January, a significant magnitude depletion of solar quiet (Sq) equivalent current was observed near noon hours around the magnetic equator (Addis Ababa, ABB) compared to any other months along with a consistent significantly reduced value across the Northern Hemisphere and moderate decrease at the Southern Hemisphere. Also, we found that Nairobi and Dar es Salaam at the Southern Hemisphere, which are close to ABB (dip equator), are strongly prone to westward electric field compared to the magnetic equator and Khartoum at the Northern Hemisphere. Significant negative values of MSq(Z) magnitudes observed near noon hours at Hermanus indicate the presence of induced currents that suggest ocean effects along with reversal to significant positive values in the afternoon, which subsided before 1800 LT in almost all the months, indicate stronger influence of ionospheric currents. On seasonal variability of Sq(H), a slight depression at ABB during September equinox is one of the evidences of seasonal Sq focus shift. Latitudinal variability of Sq near-noon hours was also investigated.

  10. AfricaArray International Geophysics Field School: Applications of Near Surface Geophysics to challenges encountered in mine planning

    NASA Astrophysics Data System (ADS)

    Webb, S. J.; Jones, M. Q.; Durrheim, R. J.; Nyblade, A.; Snyman, Q.

    2012-12-01

    Hard rock exploration and mining presents many opportunities for the effective use of near surface geophysics. For over 10 years the AfricaArray international geophysics field school has been hosted at a variety of mines in South Africa. While the main objective of the field school is practical training for the next generation of geophysicists, being hosted at a mine has allowed us to investigate applications of near surface geophysics in the early stages of mine planning and development as geophysics is often cheaper and faster than drilling. Several applications include: detailed delineation of dykes and stringer dykes, physical property measurements on drill core for modeling and marker horizons, determination of overburden thickness, locations of water and faults. Dolerite dykes are usually magnetic and are associated with loss of ground (i.e. where the dyke replaces the ore and thus reduces the amount of ore available) and safety/stability concerns. Thus the accurate mapping of dykes and narrow stringers that are associated with them are crucial to the safe planning of a mine. We have acquired several case studies where ground magnetic surveys have greatly improved on the resolution and detail of airborne magnetic surveys in regions of complicated dyke swarms. In many cases, thin stringer dykes of less than 5 cm have been detected. Physical property measurements of these dykes can be used to distinguish between different ages of dykes. It is important to accurately determine overburden thickness when planning an open pit mine as this directly affects the cost of development. Depending on the nature of the overburden, both refraction seismic and or DC resistivity can provide continuous profiling in the area of interest that fills in gaps between boreholes. DC resistivity is also effective for determining water associated with dykes and structures that may affect mine planning. The field school mainly addresses the training of a variety of students. The core

  11. Ecosystem Carbon-13 Isoscapes and Uncertainty Estimates for Africa: Integrating Remote Sensing and Field Isotope Measurements

    NASA Astrophysics Data System (ADS)

    Powell, R. L.; Yoo, E.; Still, C. J.

    2012-12-01

    relationship between fractional woody cover and the δ13C of soil organic carbon. We compare these estimates to field measurements of leaf and soil δ13C from two savanna ecosystems located in eastern and southern Africa. Finally, we develop strategies to "spatialize" relative uncertainty in our estimates of C3/C4 percent cover by integrating overall accuracy measures of global-extent datasets with local information about neighborhood variability. This represents a first step in assessing how the combination of different data sources at multiple spatial resolutions affects confidence in predicted δ13C values at specific geographic locations. We demonstrate that the highest uncertainty is found in savanna ecosystems, which contain highly heterogeneous vegetation cover and the highest percentage of C4 grass cover.

  12. Nutritional Epidemiology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although observations on relationships between diet and health have always been recognized—the systematic science of nutritional epidemiology in populations is relatively recent. Important observations propelling the field of nutrition forward were numerous in the 18th and 19th centuries, as it was...

  13. Ethical issues in epidemiological research.

    PubMed

    Hessel, P A; Fourie, P B

    1987-12-19

    Ethical concerns pervade all aspects of epidemiological investigations. Ethical issues, including planning, carrying out, analysing and presenting the results of a study, are discussed. In southern Africa, where many community-based epidemiological surveys are undertaken, issues relating specifically to the conduct of such studies are especially relevant. These include informed consent, confidentiality and privacy.

  14. Cognitive epidemiology

    PubMed Central

    Deary, Ian J; Batty, G David

    2007-01-01

    This glossary provides a guide to some concepts, findings and issues of discussion in the new field of research in which intelligence test scores are associated with mortality and morbidity. Intelligence tests are devised and studied by differential psychologists. Some of the major concepts in differential psychology are explained, especially those regarding cognitive ability testing. Some aspects of IQ (intelligence) tests are described and some of the major tests are outlined. A short guide is given to the main statistical techniques used by differential psychologists in the study of human mental abilities. There is a discussion of common epidemiological concepts in the context of cognitive epidemiology. PMID:17435201

  15. The Role of Professional Journals and Societies in the Future of a Field: A Reflection on the Partnership Between the American Journal of Epidemiology and the Society for Epidemiologic Research.

    PubMed

    Hahn, Kristen A; Galea, Sandro

    2016-03-01

    On this, the 100th anniversary of Johns Hopkins Bloomberg School of Public Health, we take the opportunity to reflect on the ties between the School, the American Journal of Epidemiology, and the Society for Epidemiologic Research. We discuss briefly the intersection of the School, the Journal, and the Society throughout their histories, with the aim of providing some insight into how the Journal and the Society have contributed to the evolution of the field. In so doing, we articulate the challenges that the Journal and the Society jointly face today, with an eye to finding opportunities in these challenges that can be helpful in coming decades. PMID:26841948

  16. The Role of Professional Journals and Societies in the Future of a Field: A Reflection on the Partnership Between the American Journal of Epidemiology and the Society for Epidemiologic Research.

    PubMed

    Hahn, Kristen A; Galea, Sandro

    2016-03-01

    On this, the 100th anniversary of Johns Hopkins Bloomberg School of Public Health, we take the opportunity to reflect on the ties between the School, the American Journal of Epidemiology, and the Society for Epidemiologic Research. We discuss briefly the intersection of the School, the Journal, and the Society throughout their histories, with the aim of providing some insight into how the Journal and the Society have contributed to the evolution of the field. In so doing, we articulate the challenges that the Journal and the Society jointly face today, with an eye to finding opportunities in these challenges that can be helpful in coming decades.

  17. Mechanisms of geomagnetic field influence on gene expression using influenza as a model system: basics of physical epidemiology.

    PubMed

    Zaporozhan, Valeriy; Ponomarenko, Andriy

    2010-03-01

    Recent studies demonstrate distinct changes in gene expression in cells exposed to a weak magnetic field (MF). Mechanisms of this phenomenon are not understood yet. We propose that proteins of the Cryptochrome family (CRY) are "epigenetic sensors" of the MF fluctuations, i.e., magnetic field-sensitive part of the epigenetic controlling mechanism. It was shown that CRY represses activity of the major circadian transcriptional complex CLOCK/BMAL1. At the same time, function of CRY, is apparently highly responsive to weak MF because of radical pairs that periodically arise in the functionally active site of CRY and mediate the radical pair mechanism of magnetoreception. It is known that the circadian complex influences function of every organ and tissue, including modulation of both NF-kappaB- and glucocorticoids- dependent signaling pathways. Thus, MFs and solar cycles-dependent geomagnetic field fluctuations are capable of altering expression of genes related to function of NF-kappaB, hormones and other biological regulators. Notably, NF-kappaB, along with its significant role in immune response, also participates in differential regulation of influenza virus RNA synthesis. Presented data suggests that in the case of global application (example-geomagnetic field), MF-mediated regulation may have epidemiological and other consequences. PMID:20617011

  18. An outbreak of cryptosporidiosis at a swimming club--can rapid field epidemiology limit the spread of illness?

    PubMed

    McCann, R; Jones, R; Snow, J; Cleary, P; Burgess, S; Bothra, V; Chalmers, R M

    2014-01-01

    In September 2010, an outbreak of cryptosporidiosis affected members of a swimming club. A cohort study was undertaken to identify the number affected and risk factors for infection. Of 101 respondents, 48 met the case definition for probable cryptosporidiosis. Multivariate analysis demonstrated a strong and highly significant association between illness and attendance at a training session on 13 September 2010 (adjusted odds ratio 28, P < 0.0001). No faecal incidents were reported and pool monitoring parameters were satisfactory. The competitive nature of club swimming requires frequent training and participation in galas, potentially facilitating contamination into other pools and amplification of outbreaks among wider groups of swimmers. There was a lack of awareness of the 2-week exclusion rule among swimmers and coaches, and a high level of underreporting of illness. The study demonstrates the benefits of rapid field epidemiology in identifying the true burden of illness, the source of infection and limiting spread.

  19. Hydrodynamic Simulations of Far-Field Tsunami Risk in the Indian Ocean, with Special Emphasis on Africa

    NASA Astrophysics Data System (ADS)

    Synolakis, C. E.; Okal, E. A.; Hartnady, C. J.

    2007-12-01

    We evaluate far-field tsunami risk in the Indian Ocean Basin based on hydrodymanic simulations of eight case studies of possible mega earthquakes at the major seismic zones surrounding the basin. They represent worst-case scenarios of seismic rupture along the full extent of seismogenic faults having supported large earthquakes in the historical record. We consider seismic sources located at the extremities of the 2004 Sumatra-Andaman rupture, namely along the Southern coast of Sumatra and in the Andaman-Myanmar province; along the Makran coast of Pakistan and Iran; and also along the Southern coast of Java, where the possibility of a large interplate thrust earthquake cannot be entirely dismissed. Following Ando's [1975] remark concerning the capricious character of segmentation during repeated mega-earthquakes at subduction zones, we consider events even bigger than identified in the historical record, especially in Southern Sumatra. We also envision risk to South Africa from a potential mega-event in the South Sandwich Islands. The results of our hydrodynamic simulations indicate that the distribution of maximum amplitudes in the Indian Ocean Basin is primarily controlled by the classical effect of source directivity, and additionally by refraction and focusing along bathymetric features. As a result, many provinces in the basin could be threatened by higher tsunami amplitudes than in 2004. This pattern is particularly important along the coast of East Africa, from Somalia to and including South Africa, in Madagascar and the Mascarene Islands, especially under a South Sumatra scenario involving an earthquake comparable to, or even possibly larger than, the 1833 event, whose epicentral area is widely believed to be under enhanced seismic risk as a result of stress transfer from the 2004 and 2005 ruptures to the Northwest.

  20. The use of pulsed-field gel electrophoresis to investigate the epidemiology of Mycoplasma bovis in French calf feedlots.

    PubMed

    Arcangioli, Marie-Anne; Aslan, Hamidé; Tardy, Florence; Poumarat, François; Le Grand, Dominique

    2012-04-01

    Mycoplasma bovis is a major cause of respiratory outbreaks in cattle feedlots. In this study pulsed-field gel electrophoresis (PFGE) was used to trace field strains and provide information on M. bovis patterns of spread in calf feedlots. The suitability of KpnI, MluI and SmaI restriction enzymes was assessed on different sets of strains. The discriminative power of the first two enzymes was first assessed using 28 epidemiologically unrelated strains; stability was 100% on multiple isolates from in vivo experimental infection. Thirty-nine field isolates from six feedlots were then evaluated. In contrast to the unique fingerprints displayed by the unrelated strains, the isolates from the feedlots showed identical patterns at the time of the outbreak of respiratory disease and 4 weeks later. The PFGE typing results suggest that M. bovis strains follow a clonal epidemic spread pattern at the herd level and that the same strain persists in calves of the herd after the clinical signs have disappeared.

  1. Interactively Improving Agricultural Field Mapping in Sub-Saharan Africa with Crowd-Sourcing and Active Learning

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Estes, L. D.; Caylor, K. K.

    2015-12-01

    As satellite imagery becomes increasingly available, management of large image databases becomes more important for efficient image processing. We have developed a computer vision-based classification algorithm to distinguish smallholder agricultural land cover in Sub-Saharan Africa, using a group of high-resolution images from South Africa as a case study. For supervised classification, smallholder agriculture, with ambiguous patterns of small, irregular fields, requires a wide range of training data samples to adequately describe the variability in appearance. We employ crowd-sourcing to obtain new training data to expand the geographic range of our algorithm. A crowd-sourcing user is asked to hand-digitize the boundaries of agricultural fields in an assigned 1 km2 image. Yet random assignment of images to users could result in a highly redundant training data set with limited discriminative power. Furthermore, larger training data sets require a greater number of users to hand-digitize fields, which increases costs through crowd-sourcing engines like Amazon Mechanical Turk, as well as longer algorithm training times, which increases computing costs. Therefore, we employ an active learning approach to interactively select the most informative images to be hand-digitized for training data by crowd-sourcing users, based on changes in algorithm accuracy. We investigate the use of various image similarity measures used in content-based image retrieval systems, which quantify the distance, such as Euclidean distance or Manhattan distance, between a variety of extracted feature spaces to determine how similar the content of two images are. We determine the minimum training data set needed to maximize algorithm accuracy, as well as automate the selection of additional training images to classify a new target image that expands the geographic range of our algorithm.

  2. Characteristics and comprehensiveness of adult HIV care and treatment programmes in Asia-Pacific, sub-Saharan Africa and the Americas: results of a site assessment conducted by the International epidemiologic Databases to Evaluate AIDS (IeDEA) Collaboration

    PubMed Central

    Duda, Stephany N; Farr, Amanda M; Lindegren, Mary Lou; Blevins, Meridith; Wester, C William; Wools-Kaloustian, Kara; Ekouevi, Didier K; Egger, Matthias; Hemingway-Foday, Jennifer; Cooper, David A; Moore, Richard D; McGowan, Catherine C; Nash, Denis

    2014-01-01

    Introduction HIV care and treatment programmes worldwide are transforming as they push to deliver universal access to essential prevention, care and treatment services to persons living with HIV and their communities. The characteristics and capacity of these HIV programmes affect patient outcomes and quality of care. Despite the importance of ensuring optimal outcomes, few studies have addressed the capacity of HIV programmes to deliver comprehensive care. We sought to describe such capacity in HIV programmes in seven regions worldwide. Methods Staff from 128 sites in 41 countries participating in the International epidemiologic Databases to Evaluate AIDS completed a site survey from 2009 to 2010, including sites in the Asia-Pacific region (n=20), Latin America and the Caribbean (n=7), North America (n=7), Central Africa (n=12), East Africa (n=51), Southern Africa (n=16) and West Africa (n=15). We computed a measure of the comprehensiveness of care based on seven World Health Organization-recommended essential HIV services. Results Most sites reported serving urban (61%; region range (rr): 33–100%) and both adult and paediatric populations (77%; rr: 29–96%). Only 45% of HIV clinics that reported treating children had paediatricians on staff. As for the seven essential services, survey respondents reported that CD4+ cell count testing was available to all but one site, while tuberculosis (TB) screening and community outreach services were available in 80 and 72%, respectively. The remaining four essential services – nutritional support (82%), combination antiretroviral therapy adherence support (88%), prevention of mother-to-child transmission (PMTCT) (94%) and other prevention and clinical management services (97%) – were uniformly available. Approximately half (46%) of sites reported offering all seven services. Newer sites and sites in settings with low rankings on the UN Human Development Index (HDI), especially those in the President's Emergency Plan

  3. A Comment on Results of Recent Pooled Analyses of Epidemiological Papers Related to Cancer and Power-Line Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Amemiya, Yoshifumi

    In June 2001, the International Agency for Research on Cancer (IARC) classified ELF magnetic fields as a possible human carcinogen based on the results of two recent pooled analyses by Ahlbom et al. and Greenland et al. on epidemiological papers for childhood leukemia. Examining the data displayed by them, this author succeeded to read the other informations than theirs: in the paper of Ahlbom et al., for instance, 9 cases were prepared for verifying the hypothesis that magnetic fields are associated with childhood leukemia, and this author considers that the general conclusion derived by inductive inference is that the hypothesis is not supported, because 2 cases out of 9 support the hypothesis and 7 cases do not support the hypothesis, although the hypothesis has been believed by many people for about twenty years; furthermore, the author does not consider that the IARC’s evaluation that risk doubles in excess of 3 or 4 mG is based on the general conclusion, because it comes from pooling two kinds of data, one of which is of 7 cases bringing the ‘general conclusion’, and the other of the remained 2 cases being the ‘particular facts’.

  4. Evaluating exposure cutpoint bias in epidemiologic studies of electric and magnetic fields

    SciTech Connect

    Wartenberg, D.; Savitz, D.A. )

    1993-01-01

    Epidemiologists who study the association between exposure to electric or magnetic fields and adverse health outcomes often classify their subjects as exposed and unexposed, and they report results based on an odds ratio. The exposure classification rule--or dichotomy rule--is typically based on a priori assumptions or arbitrary considerations. We show that results may vary substantially with selection of different cutpoints by which to dichotomize exposure. Further, interpretation and comparison of studies is dependent on the choice of cutpoint. We suggest the use of probability plots as a more informative method of data representation. To demonstrate the utility of probability plots, we re-analyze data reported by Savitz et al. [1988, Am J Epidemiol 128:21-38]. Using a higher exposure cutpoint than that of the original analysis, we obtained larger odds ratios, two of which achieved statistical significance. More important, probability plots of these data showed (1) consistency of results with measures of magnetic fields in both low- and high-power-use situations, and (2) discordance with results based on measures of electric fields. Given these observations, we recommend further study, especially that focused on the most highly exposed individuals.

  5. The epidemiology of favism.

    PubMed

    Belsey, M A

    1973-01-01

    Favism is a potential obstacle to the use of the fava bean in the development of a locally produced, inexpensive weaning food for the Middle East and North Africa. The purposes of this study were to define the epidemiology of favism, to evaluate the advisability of using the fava bean in a weaning food, and to suggest ways of avoiding or eliminating the toxic factor in the bean. Field observations, locally acquired data, and a literature review suggested that the use of the fava bean in a weaning food would be hazardous, but that the hazard might be overcome by using certain strains of the bean or, more particularly, by using old dried beans. The disease is usually directly related in time to the harvesting and availability of fresh beans, but it is also associated with fresh dried beans. On the basis of the age distribution of the disease, patterns of bean consumption, and local food taboos it appears that the toxic factor is concentrated in the skin of the bean, that it is heat-stable, that in dried beans it decreases with age, and that it crosses into the breast milk of lactating mothers. It also appears that disease expression may be a result of the interaction of several host factors, such as nutritional status and the consumption of other foods. These observations are consistent with the results of laboratory studies, which incriminate vicine, divicine, and DOPA in the etiology of favism.

  6. The epidemiology of favism

    PubMed Central

    Belsey, Mark A.

    1973-01-01

    Favism is a potential obstacle to the use of the fava bean in the development of a locally produced, inexpensive weaning food for the Middle East and North Africa. The purposes of this study were to define the epidemiology of favism, to evaluate the advisability of using the fava bean in a weaning food, and to suggest ways of avoiding or eliminating the toxic factor in the bean. Field observations, locally acquired data, and a literature review suggested that the use of the fava bean in a weaning food would be hazardous, but that the hazard might be overcome by using certain strains of the bean or, more particularly, by using old dried beans. The disease is usually directly related in time to the harvesting and availability of fresh beans, but it is also associated with fresh dried beans. On the basis of the age distribution of the disease, patterns of bean consumption, and local food taboos it appears that the toxic factor is concentrated in the skin of the bean, that it is heat-stable, that in dried beans it decreases with age, and that it crosses into the breast milk of lactating mothers. It also appears that disease expression may be a result of the interaction of several host factors, such as nutritional status and the consumption of other foods. These observations are consistent with the results of laboratory studies, which incriminate vicine, divicine, and DOPA in the etiology of favism. PMID:4541143

  7. Struggling with AIDS in South Africa: the space of the everyday as a field of recognition.

    PubMed

    Le Marcis, Frédéric

    2012-12-01

    The space of volunteering is often seen as a place for rebuilding a world for individuals for whom life has been destroyed by the discovery of AIDS infection. People living with AIDS get involved in HIV support groups, become volunteers, and take care for each other. Without denying the reality of these processes leading to a "positive life" this article questions narratives of the transformation of the self-implied in the "caring for other" logic and argues that other spheres of life, less discernable because inscribed in the ordinary and in the intimacy of domestic life are at least as important as the involvement in biomedical care. The limits of voluntary work is highlighted and contrasted with a presentation of how life, love and affection is reconfigured within everyday life, leading to a consideration of people's struggles to build spaces of recognition. The argument of this article is built on a three year ethnography (2001-04) carried out in Soweto and Alexandra townships (South Africa). PMID:23361881

  8. Quantitative and molecular epidemiology of bacterial blight of onion in seed production fields.

    PubMed

    Humeau, L; Roumagnac, P; Picard, Y; Robène-Soustrade, I; Chiroleu, F; Gagnevin, L; Pruvost, O

    2006-12-01

    ABSTRACT Onion, a biennial plant species, is threatened by the emerging, seed-borne, and seed-transmitted Xanthomonas axonopodis pv. allii. Bacterial blight epidemics were monitored in seed production fields over two seasons. Temporal disease progress was different between the two seasons, with final incidence ranging from 0.04 to 0.06 in 2003 and from 0.44 to 0.61 in 2004. The number of hours with temperatures above 24 degrees C was the best descriptor for predicting the number of days after inoculation for bacterial blight development on inoculated plants. Fitting the beta-binomial distribution and binary power law analysis indicated aggregated patterns of disease incidence data. The beta-binomial distribution was superior to the binomial distribution for 97% of the examined data sets. Spatial dependency ranged from 5.9 to 15.2 m, as determined by semivariance analysis. Based on amplified fragment length polymorphism (AFLP) analysis, it was concluded that plots predominantly were infected by the inoculated haplotype. A single other haplotype was identified by AFLP in all plots over the 2 years, and its detection in the field always followed wind-driven rains. X. axonopodis pv. allii-contaminated seed were detected by semiselective isolation and a nested polymerase chain reaction assay at levels up to 0.05% when final disease incidence was 0.61. Contaminated seed originated from both diseased and asymptomatic plants.

  9. Molecular epidemiology of rabies: focus on domestic dogs (Canis familiaris) and black-backed jackals (Canis mesomelas) from northern South Africa.

    PubMed

    Zulu, G C; Sabeta, C T; Nel, L H

    2009-03-01

    Phylogenetic relationships of rabies viruses recovered from black-backed jackals (Canis mesomelas) and domestic dogs (Canis familiaris) in northern South Africa were investigated to determine whether the black-backed jackal is an emerging maintenance host species for rabies in this region. A panel of 123 rabies viruses obtained from the two host species between 1980 and 2006 were characterised by nucleotide sequencing of the cytoplasmic domain of the glycoprotein gene and the non-coding G-L intergenic region. Through phylogenetic analysis a viral cluster specific to black-backed jackals and spanning a 5-year period was delineated in western Limpopo. Virus strains associated with domestic dogs prevail in densely populated communal areas in north-eastern Limpopo and in south and eastern Mpumalanga. The data presented in this study indicated the likelihood that black-backed jackals are capable of sustaining rabies cycles independent of domestic dogs. It is proposed that wildlife rabies control strategies, in synergy with domestic animal vaccination should be considered for effective control of rabies in South Africa. PMID:19061924

  10. Molecular epidemiology of rabies: focus on domestic dogs (Canis familiaris) and black-backed jackals (Canis mesomelas) from northern South Africa.

    PubMed

    Zulu, G C; Sabeta, C T; Nel, L H

    2009-03-01

    Phylogenetic relationships of rabies viruses recovered from black-backed jackals (Canis mesomelas) and domestic dogs (Canis familiaris) in northern South Africa were investigated to determine whether the black-backed jackal is an emerging maintenance host species for rabies in this region. A panel of 123 rabies viruses obtained from the two host species between 1980 and 2006 were characterised by nucleotide sequencing of the cytoplasmic domain of the glycoprotein gene and the non-coding G-L intergenic region. Through phylogenetic analysis a viral cluster specific to black-backed jackals and spanning a 5-year period was delineated in western Limpopo. Virus strains associated with domestic dogs prevail in densely populated communal areas in north-eastern Limpopo and in south and eastern Mpumalanga. The data presented in this study indicated the likelihood that black-backed jackals are capable of sustaining rabies cycles independent of domestic dogs. It is proposed that wildlife rabies control strategies, in synergy with domestic animal vaccination should be considered for effective control of rabies in South Africa.

  11. Fostering Transformative Learning in Non-Formal Settings: Farmer-Field Schools in East Africa

    ERIC Educational Resources Information Center

    Taylor, Edward W.; Duveskog, Deborah; Friis-Hansen, Esbern

    2012-01-01

    The purpose of this study was to explore the practice of Farmer-Field Schools (FFS) theoretically framed from the perspective of transformative learning theory and non-formal education (NFE). Farmer-Field Schools are community-led NFE programs that provide a platform where farmers meet regularly to study the "how and why" of farming and engage in…

  12. Epidemiological investigation of Salmonella tilene by pulsed-field gel electrophoresis and polymerase chain reaction

    PubMed Central

    Anand, Chandar M; Fonseca, Kevin; Longmore, Ken; Rennie, Robert; Chui, Linda; Lingley, Mike; Woodward, David

    1997-01-01

    Pulsed-field gel electrophoresis (PFGE) and DNA fingerprinting by the polymerase chain reaction (PCR) were performed on 11 isolates of Salmonella tilene. Five strains were from a cluster of human patients, six from sugar gliders and pygmy hedgehogs kept as family pets or from local pet retailers, and one isolate from the first North American case of S tilene described in Washington State in 1994. The PFGE restriction patterns showed all isolates to be similar. However, PCR using primers to the 16S and 23S rRNA genes of Escherichia coli demonstrated that the Washington State isolate differed from the rest of the other isolates, which were all similar based upon their DNA fingerprint. This study indicates that reliance on one technique alone may be insufficient to show nuances between strains that are, in many respects, closely related. PMID:22346526

  13. Intercomparison of passive radon-detectors under field conditions in epidemiological studies

    SciTech Connect

    Kreienbrock, L. ); Poffijn, A. ); Tirmarche, M. ); Feider, M. ); Kies, A. ); Darby, S.C. )

    1999-05-01

    The Ardennes and Eifel region is a geologically distinct area covering parts of Germany, Belgium, France, and Luxembourg where enhanced concentrations of radon occur in some houses and other buildings. An international case-control study is being conducted to examine the role of radon in the etiology of lung cancer in this area. The radon detectors used are issued by different laboratories involving a variety of detector types and processes. A series of intercomparisons in houses was therefore conducted under similar conditions of exposure in the field. In most situations the different detectors gave similar results. Nevertheless, in some situations open and closed detectors yielded different results. Therefore, estimates of radon exposure have to be adjusted if results are to be pooled.

  14. South Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image of South Africa was acquired on May 14, 2000, by NASA's Moderate-resolution Imaging Spectroradiometer, or MODIS. The image was produced using a combination of the sensor's 250-m and 500-m resolution visible wavelength bands. As part of the opening ceremony to begin the joint U.S.-South Africa SAFARI Field Experiment, NASA presented print copies of this image as GIFts to Dr. Ben Ngubane, Minister of Arts, Science and Technology, and Honorable Advocate Ngoaka Ramathlodi, Premier of the Northern Province, South Africa. The area shown in this image encompasses seven capital cities and a number of the region's distinctive geological features can be seen clearly. Toward the northern (top) central part of the image, the browns and tans comprise the Kalahari Desert of southern Botswana. The Tropic of Capricorn runs right through the heart of the Kalahari and the Botswanan capital city of Gaborone sits on the Limpopo River, southeast of the Kalahari. Along the western coastline of the continent is the country of Namibia, where the Namib Desert is framed against the sea by the Kaokoveld Mountains. The Namibian capital of Windhoek is obscured by clouds. Looking closely in the center of the image, the Orange River can be seen running from east to west, demarcating the boundary between Namibia and South Africa. On the southwestern corner of the continent is the hook-like Cape of Good Hope peninsula and Cape Town, the parliamentary capital of South Africa. Running west to east away from Cape Town are the Great Karroo Mountains. The shadow in this image conveys a sense of the very steep grade of the cliffs along the southern coast of South Africa. Port Elizabeth sits on the southeasternmost point of South Africa, and a large phytoplankton bloom can be seen in the water about 100 miles east of there. Moving northward along the east coast, the Drakensberg Mountains are visible. The two small nations of Lesotho and Swaziland are in this region, completely

  15. Wild Bird Surveillance for Avian Paramyxoviruses in the Azov-Black Sea Region of Ukraine (2006 to 2011) Reveals Epidemiological Connections with Europe and Africa

    PubMed Central

    Pantin-Jackwood, Mary; Stegniy, Borys; Rula, Oleksandr; Bolotin, Vitaliy; Stegniy, Anton; Gerilovych, Anton; Shutchenko, Pavlo; Stegniy, Maryna; Koshelev, Vasyl; Maiorova, Klavdii; Tkachenko, Semen; Muzyka, Nataliia; Usova, Larysa; Afonso, Claudio L.

    2014-01-01

    Despite the existence of 10 avian paramyxovirus (APMV) serotypes, very little is known about the distribution, host species, and ecological factors affecting virus transmission. To better understand the relationship among these factors, we conducted APMV wild bird surveillance in regions of Ukraine suspected of being intercontinental (north to south and east to west) flyways. Surveillance for APMV was conducted in 6,735 wild birds representing 86 species and 8 different orders during 2006 to 2011 through different seasons. Twenty viruses were isolated and subsequently identified as APMV-1 (n = 9), APMV-4 (n = 4), APMV-6 (n = 3), and APMV-7 (n = 4). The highest isolation rate occurred during the autumn migration (0.61%), with viruses isolated from mallards, teals, dunlins, and a wigeon. The rate of isolation was lower during winter (December to March) (0.32%), with viruses isolated from ruddy shelducks, mallards, white-fronted geese, and a starling. During spring migration, nesting, and postnesting (April to August) no APMV strains were isolated out of 1,984 samples tested. Sequencing and phylogenetic analysis of four APMV-1 and two APMV-4 viruses showed that one APMV-1 virus belonging to class 1 was epidemiologically linked to viruses from China, three class II APMV-1 viruses were epidemiologically connected with viruses from Nigeria and Luxembourg, and one APMV-4 virus was related to goose viruses from Egypt. In summary, we have identified the wild bird species most likely to be infected with APMV, and our data support possible intercontinental transmission of APMVs by wild birds. PMID:24973063

  16. Wild bird surveillance for avian paramyxoviruses in the Azov-black sea region of Ukraine (2006 to 2011) reveals epidemiological connections with Europe and Africa.

    PubMed

    Muzyka, Denys; Pantin-Jackwood, Mary; Stegniy, Borys; Rula, Oleksandr; Bolotin, Vitaliy; Stegniy, Anton; Gerilovych, Anton; Shutchenko, Pavlo; Stegniy, Maryna; Koshelev, Vasyl; Maiorova, Klavdii; Tkachenko, Semen; Muzyka, Nataliia; Usova, Larysa; Afonso, Claudio L

    2014-09-01

    Despite the existence of 10 avian paramyxovirus (APMV) serotypes, very little is known about the distribution, host species, and ecological factors affecting virus transmission. To better understand the relationship among these factors, we conducted APMV wild bird surveillance in regions of Ukraine suspected of being intercontinental (north to south and east to west) flyways. Surveillance for APMV was conducted in 6,735 wild birds representing 86 species and 8 different orders during 2006 to 2011 through different seasons. Twenty viruses were isolated and subsequently identified as APMV-1 (n = 9), APMV-4 (n = 4), APMV-6 (n = 3), and APMV-7 (n = 4). The highest isolation rate occurred during the autumn migration (0.61%), with viruses isolated from mallards, teals, dunlins, and a wigeon. The rate of isolation was lower during winter (December to March) (0.32%), with viruses isolated from ruddy shelducks, mallards, white-fronted geese, and a starling. During spring migration, nesting, and postnesting (April to August) no APMV strains were isolated out of 1,984 samples tested. Sequencing and phylogenetic analysis of four APMV-1 and two APMV-4 viruses showed that one APMV-1 virus belonging to class 1 was epidemiologically linked to viruses from China, three class II APMV-1 viruses were epidemiologically connected with viruses from Nigeria and Luxembourg, and one APMV-4 virus was related to goose viruses from Egypt. In summary, we have identified the wild bird species most likely to be infected with APMV, and our data support possible intercontinental transmission of APMVs by wild birds.

  17. The future of epidemiology.

    PubMed

    Ness, Roberta B; Andrews, Elizabeth B; Gaudino, James A; Newman, Anne B; Soskolne, Colin L; Stürmer, Til; Wartenberg, Daniel E; Weiss, Stanley H

    2009-11-01

    In this article, the authors discuss current challenges and opportunities in epidemiology that will affect the field's future. Epidemiology is commonly considered the methodologic backbone for the fields of public health and outcomes research because its practitioners describe patterns of disease occurrence, identify risk factors and etiologic determinants, and demonstrate the usefulness of interventions. Like most aspects of science, epidemiology is in rapid flux. Several factors that are influencing and will continue to influence epidemiology and the health of the public include factors fundamental to framing the discipline of epidemiology (i.e., its means of communication, its methodologies, its access to data, its values, its population perspective), factors relating to scientific advances (e.g., genomics, comparative effectiveness in therapeutics), and factors shaping human health (e.g., increasing globalism, the environment, disease and lifestyle, demographics, infectious disease). PMID:19858828

  18. The close genetic relationship of lineage D Betacoronavirus from Nigerian and Kenyan straw-colored fruit bats (Eidolon helvum) is consistent with the existence of a single epidemiological unit across sub-Saharan Africa.

    PubMed

    Leopardi, Stefania; Oluwayelu, Daniel; Meseko, Clement; Marciano, Sabrina; Tassoni, Luca; Bakarey, Solomon; Monne, Isabella; Cattoli, Giovanni; De Benedictis, Paola

    2016-08-01

    Straw-colored fruit bats (Eidolon helvum), which have been identified as natural hosts for several zoonotic pathogens, such as lyssaviruses, henipaviruses, and ebolavirus, are associated with human settlements in Nigeria where they are commonly consumed as a delicacy. However, information on the viruses harbored by these bats is scarce. In this study, coronavirus sequences were detected using a nested RT-PCR targeting 440 bp of the RNA-dependent RNA polymerase (RdRp) in six of 79 fecal samples collected from an urban colony of E. helvum in Ibadan, Nigeria. Phylogenetic analysis revealed that all six sequences were monophyletic and clustered in lineage D of Betacoronavirus. The extension of two fragments allowed us to classify our sequences within the RdRp Group Unit defined for Kenyan Betacoronavirus from the same host species. These findings are consistent with the previous suggestion on the existence of a single epidemiological unit of E. helvum across sub-Saharan Africa. This theory, which is supported by the genetic structure of continental E. helvum, could facilitate viral mixing between different colonies across the continent. PMID:27059240

  19. Agricultural fields, Khartoum, Sudan, Africa Description: This herringbone pattern of irrigated

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) was imaged with infrared film as part an experiment to compare the merits of color film versus color infrared film. Color film presents the image as it appears to the eye whereas color infrared film has an excellent haze penetration and vegetation definition capability. See color film image STS049-77-072 for a detailed scene description.

  20. Use of automated riboprinter and pulsed-field gel electrophoresis for epidemiological studies of invasive Haemophilus influenzae in Taiwan.

    PubMed

    Wang, C C; Siu, L K; Chen, M K; Yu, Y L; Lin, F M; Ho, M; Chu, M L

    2001-03-01

    A total of 87 invasive isolates of Haemophilus influenzae isolated throughout Taiwan from 1994 to 1998 was collected; 57 were from children <14 years old. In all, 60.9% of isolates were resistant to ampicillin and produced beta-lactamase. Ribotyping revealed six different profiles in 55 isolates of type b, nine profiles in 10 isolates of non-type b and 12 profiles in 22 isolates of non-typable H. influenzae. Among isolates from 35 cases of meningitis, 30 (86%) were in ribogroups 1, 2 and 3 with >90% genetic similarity. Compared with all the other ribogroups, ribogroups 1, 2 and 3, which encompassed all H. influenzae type b, were significantly more prevalent as a cause of meningitis in children <14 years old. Further subtyping of the predominant ribogroup by pulsed-field gel electrophoresis (PFGE) identified differences of 0-6 bands among these isolates of ribogroup 1, which indicated distant relatedness. Automated ribotyping was found to be a useful method and was less time-consuming for molecular epidemiology studies of H. influenzae. PFGE is suggested as an addition to ribotyping to improve discrimination if H. influenzae type b is involved. Differentiating ribogroups between type b and non-type b H. influenzae by genotyping may help to understand the molecular characteristics of outbreaks, endemicity and value of vaccination. According to the results of ribotyping and PFGE, it seems possible that spread of invasive H. influenzae type b had occurred and ribotyping confirmed that there was no clonal spread of non-type b H. influenzae in Taiwan.

  1. Epidemiologic analysis of sporadic Salmonella typhi isolates and those from outbreaks by pulsed-field gel electrophoresis.

    PubMed Central

    Thong, K L; Cheong, Y M; Puthucheary, S; Koh, C L; Pang, T

    1994-01-01

    Pulsed-field gel electrophoresis (PFGE) was used to compare and analyze 158 isolates of Salmonella typhi from five well-defined outbreaks of typhoid fever in Malaysia and also isolates involved in sporadic cases of typhoid fever occurring during the same period. Digestion of chromosomal DNAs from these S. typhi isolates with the restriction endonucleases XbaI (5'-TCTAGA-3'), SpeI (5'-ACTAGT-3'), and AvrII (5'-CCTAGG-3') and then PFGE produced restriction endonuclease analysis (REA) patterns consisting of 11 to 24 DNA fragments ranging in size from 20 to 630 kbp. Analysis of the REA patterns generated by PFGE after digestion with XbaI and SpeI indicated that the S. typhi isolates obtained from sporadic cases of infection were much more heterogeneous (at least 13 different REA patterns were detected; Dice coefficient, between 0.73 and 1.0) than those obtained during outbreaks of typhoid fever. The clonal nature and the close genetic identities of isolates from outbreaks in Alor Setar, Penang, Kota Kinabalu, Johor Bahru, and Kota Bahru were suggested by the fact that only a limited number of REA patterns, which mostly differed by only a single band, were detected (one to four patterns; Dice coefficient, between 0.82 and 1.0), although a different pattern was associated with each of these outbreaks. Comparison of REA patterns with ribotyping for 18 S. typhi isolates involved in sporadic cases of infection showed a good correlation, in that 72% of the isolates were in the same group. There was no clear correlation of phage types with a specific REA pattern. We conclude that PFGE of s. typhi chromosomal DNA digested with infrequently cutting restriction endonucleases is a useful method for comparing and differentiating S. typhi isolates for epidemiological purposes. Images PMID:7914202

  2. Assessing and Improving Land Surface Model Outputs Over Africa Using GRACE, Field, and Remote Sensing Data

    NASA Astrophysics Data System (ADS)

    Ahmed, Mohamed; Sultan, Mohamed; Yan, Eugene; Wahr, John

    2016-05-01

    The Gravity Recovery and Climate Experiment (GRACE), along with other relevant field and remote sensing datasets, was used to assess the performance of two land surface models (LSMs: CLM4.5-SP and GLDAS-Noah) over the African continent and improve the outputs of the CLM4.5-SP model. Spatial and temporal analysis of monthly (January 2003-December 2010) Terrestrial Water Storage (TWS) estimates extracted from GRACE (TWSGRACE), CLM4.5-SP (TWSCLM4.5), and GLDAS-Noah (TWSGLDAS) indicates the following: (1) compared to GRACE, LSMs overestimate TWS in winter months and underestimate them in summer months; (2) the amplitude of annual cycle (AAC) of TWSGRACE is higher than that of TWSLSM (AAC: TWSGRACE > TWSGLDAS > TWSCLM4.5); (3) higher, and statistically significant correlations were observed between TWSGRACE and TWSGLDAS compared to those between TWSGRACE and TWSCLM4.5; (4) differences in forcing precipitation and temperature datasets for GLDAS-Noah and CLM4.5-SP models are unlikely to be the main cause for the observed discrepancies between TWSGRACE and TWSLSM; and (5) the CLM4.5-SP model overestimates evapotranspiration (ET) values in summer months and underestimates them in winter months compared to ET estimates extracted from field-based (FLUXNET-MTE) and satellite-based (MOD16 and GLEAM) ET measurements. A first-order correction was developed and applied to correct the CLM4.5-derived ET, soil moisture, groundwater, and TWS. The corrections improved the correspondence (i.e., higher correlation and comparable AAC) between TWSCLM4.5 and TWSGRACE over various climatic settings. Our findings suggest that similar straightforward correction approaches could potentially be developed and used to assess and improve the performance of a wide range of LSMs.

  3. Circular epidemiology.

    PubMed

    Kuller, L H

    1999-11-01

    Circular epidemiology can be defined as the continuation of specific types of epidemiologic studies beyond the point of reasonable doubt of the true existence of an important association or the absence of such an association. Circular epidemiology is an extreme example of studies of the consistency of associations. A basic problem for epidemiology is the lack of a systematic approach to acquiring new knowledge to reach a goal of improving public health and preventive medicine. For epidemiologists, research support unfortunately is biased toward the continued study of already proven hypotheses. Circular epidemiology, however, freezes at one point in the evolution of epidemiologic studies, failing to move from descriptive to analytical case-control and longitudinal studies, for example, to experimental, clinical trials. Good epidemiology journals are filled with very well-conducted epidemiologic studies that primarily repeat the obvious or are variations on the theme.

  4. The Upper Mantle Flow Field around South-Africa as Reflected by Isotopic Provinciality

    NASA Astrophysics Data System (ADS)

    Meyzen, C.; Blichert-Toft, J.; Ludden, J.; Humler, E.; Mevel, C.; Albarede, F.

    2006-12-01

    Isotopic studies of MORB have established the existence of broad isotopic provinces within the underlying asthenosphere, such as in the Indian Ocean (DUPAL). How these features relate to mantle circulation is, however, still unknown. The steepness of the transition between such isotopic provinces will define the geometry of the velocity field in the upper mantle. In this respect, the transition between the Indian and South Atlantic provinces, two domains that are isotopically contrasted, should be readily identifiable over this long ridge segment. Here, we present Hf isotope data for 60 samples dredged along the SWIR between 35° and 69°E. The new Hf isotope data show that the Indian asthenosphere does not spill directly into the South Atlantic upper mantle: the general decreasing southward gradient observed for ^{176}Hf/^{177}Hf down the mid- Atlantic Ridge, and also for Sr isotopes and model Th/U ratios (derived from Pb isotopes), is overprinted by material with radiogenic Sr, unradiogenic Hf and high Th/U. The Indian domain grades into the South Atlantic around Bouvet, while the South Atlantic collides with the Atlantic province around Tristan. We interpret these features to represent fronts between three adjacent isotopic provinces similar to what has been suggested for the Australian-Antarctic Discordance. The common DUPAL signature of MORB and OIB from the Indian province and the geochemistry of Gulf of Aden MORB and the Afar plume suggest that the source of this distinctive mantle component is deep and lies to the north of the province. This is also what the three-dimensional flow field computed by Behn et al. (2004) from shear-wave splitting shows with a major lower mantle upwelling radiating at the base of the asthenosphere under the Afar plume. Lower mantle gushing out from this source flows southward unimpeded along the Indian ridges, whereas it only reaches the South Atlantic ridge after first having been deflected under the deep roots of the South

  5. Recreational and occupational field exposure to freshwater cyanobacteria – a review of anecdotal and case reports, epidemiological studies and the challenges for epidemiologic assessment

    PubMed Central

    Stewart, Ian; Webb, Penelope M; Schluter, Philip J; Shaw, Glen R

    2006-01-01

    Cyanobacteria are common inhabitants of freshwater lakes and reservoirs throughout the world. Under favourable conditions, certain cyanobacteria can dominate the phytoplankton within a waterbody and form nuisance blooms. Case reports and anecdotal references dating from 1949 describe a range of illnesses associated with recreational exposure to cyanobacteria: hay fever-like symptoms, pruritic skin rashes and gastro-intestinal symptoms are most frequently reported. Some papers give convincing descriptions of allergic reactions while others describe more serious acute illnesses, with symptoms such as severe headache, pneumonia, fever, myalgia, vertigo and blistering in the mouth. A coroner in the United States found that a teenage boy died as a result of accidentally ingesting a neurotoxic cyanotoxin from a golf course pond. This death is the first recorded human fatality attributed to recreational exposure to cyanobacteria, although uncertainties surround the forensic identification of the suspected cyanotoxin in this case. We systematically reviewed the literature on recreational exposure to freshwater cyanobacteria. Epidemiological data are limited, with six studies conducted since 1990. Statistically significant increases in symptoms were reported in individuals exposed to cyanobacteria compared to unexposed counterparts in two Australian cohort studies, though minor morbidity appeared to be the main finding. The four other small studies (three from the UK, one Australian) did not report any significant association. However, the potential for serious injury or death remains, as freshwater cyanobacteria under bloom conditions are capable of producing potent toxins that cause specific and severe dysfunction to hepatic or central nervous systems. The exposure route for these toxins is oral, from ingestion of recreational water, and possibly by inhalation. A range of freshwater microbial agents may cause acute conditions that present with features that resemble

  6. Yombo field exploration model, peoples Republic of the Congo, west Africa

    SciTech Connect

    Nibbelink, K.A.; Sorgenfrei, M.C.; Rice, D.E. )

    1993-09-01

    Yombo field in the Congo is sourced from the lacustrine shales of the presalt rift stage and produces from the Albian and Cenomanian, postsalt, Sendji carbonate and Tchala Sandstone. The Yombo prospect exploration model included an upper Sendji stratigraphic trap with two components and a structural nose. The buried hill component of the trap is formed by topographic relief on the reservoir below the top Sendji unconformity. The lower Sendji slump blocks provide a high on which the upper Sendji grainstone shoal facies develop. Both depositional relief and erosion during the top Sendji unconformity contribute to the topography. An isochron thick in the overlying Tchala valley-fill sediments defined a drainage pattern on the unconformity around the buried hill of the underlying upper Sendji. The facies change component is formed by the pinch-out of the grainstone shoal reservoir facies into porous, but impermeable lagoonal dolomite interbedded with anhydrite and shale. Capillary pressure measurements on the 16% porosity, 0.1 md permeability lagoonal dolomite, along with pore throat radius and buoyancy calculations, demonstrated this facies could trap a significant column of low-gravity oil at shallow depth. The Tchala Sandstone contains several separate hydrocarbon accumulations. A stratigraphic trap in the lower Tchala is formed by marine and tidal channel sandstones pinching out into lagoonal shales. The nearshore marine sandstones of the upper Tchala contain additional hydrocarbons in structural and stratigraphic traps. The stratigraphic pinch-out that cross the Yombo nose trap a significant hydrocarbon accumulation, even though the four-way structural closure is relatively small.

  7. Improving regional health care in West Africa using current space systems and technology

    NASA Technical Reports Server (NTRS)

    Jemison, Mae C.; Thomas, J. S.

    1992-01-01

    This paper discusses the issues involved with establishing an integrated satellite health network in West Africa based on currently available technology. The system proposed makes use of a central national facility capable of transmitting and receiving voice/data and video signals from the entire country. Regional, field and local facilities provides timely epidemiologic information, sharing of medical expertise through telemedical consultations, enhances optimized resource distribution and builds a framework for telecommunications for the entire country.

  8. Improving regional health care in West Africa using current space systems and technology

    NASA Technical Reports Server (NTRS)

    Jemison, Mae C.; Thomas, J. Segun

    1992-01-01

    This paper discusses the issues involved with establishing an integrated satellite health network in West Africa based on currently available technology. The system proposed makes use of a central national facility capable of transmitting and receiving voice/data and video signals from the entire country. Regional, field and local facilities provide timely epidemiologic information, sharing of medical expertise through telemedical consultations, enhance optimized resource distribution and build a framework for telecommunications for the entire country.

  9. [Epidemiological research in Brazil].

    PubMed

    Guimarães, R; Lourenço-De-Oliveira, R; Cosac, S

    2001-08-01

    The current epidemiological research in Brazil is described. Secondary data sources were consulted, such as the year 2000 database of the Brazilian Directory of Research Groups and the National Board of Scientific and Technological Development (CNPq). The criterion to identify a group as a research one relies on the existence of at least one research line in the field of epidemiology, as defined by the group leader. After identifying the defined universe of epidemiological research, which included 176 groups and 320 different research lines, the following issues were presented and discussed: the relationships between research financing and health research, focusing on CAPES (Coordination Center for the Advance of University Professionals) graduation programs, public health research and epidemiological research, geographic and institutional distribution and outreach of the current epidemiological research, the researchers and students directly participating in epidemiological research, research topics and patterns of disseminating research findings; the journals where papers in its fullness were published; the financial support of the epidemiological research focusing on the 23 officially recognized graduate programs in public health field. PMID:11600921

  10. [Epidemiological situation of Chad].

    PubMed

    Korzeniewski, Krzysztof

    2008-10-01

    Chad, the land located in Central Africa nowadays is one of the poorest countries in the world, what is connected with catastrophic demographic indicators and numerous cases of infectious diseases among local population as well as external and internal refugees. Epidemiologic profile is dominated by vector-, water-, food-borne, respiratory, and sexually transmitted diseases. Environmental factors, such as an effect of high temperature, sand and dust storms also pose essential threat. This is related to location of majority of Chad territory in the area of Sahara and Sahel. The article presents information concerning current epidemiological hazards encountered by visitors in this country. This knowledge is essential for Polish health service and armed forces in the context of forming of EUFOR mission in Chad with participation of our soldiers.

  11. Some unsolved problems in the epidemiology of onchocerciasis.

    PubMed

    Southgate, B A

    1987-01-01

    The descriptive epidemiology of onchocerciasis is well understood in the major foci of infection; a great stimulus to epidemiological research has been the implementation of the first control programme, which led to the eradication of infection in Kenya and, more recently, the vast Onchocerciasis Control Programme in the Volta River Basin of West Africa. However, there are still significant gaps in epidemiological knowledge which hamper the planning of future control programmes and the evaluation of current programmes. The four most important unsolved problems are: the refinement of field diagnostic techniques to identify skin microfilariae at the ultra-low densities that will become common in the late stages of vector-control campaigns; the definitive identification of Onchocerca volvulus infective larvae in Simulium species; strain analysis in the field of microfilariae from humans and of developing stages from Simulium, to determine their potential for ocular pathogenicity; determination of the lifespan, or maximum fecundity span, of adult female O. volvulus after the interruption of transmission. Three other unsolved problems are of enormous interest epidemiologically, although less urgent in practical importance. They are the identification of factors causing severe disease as opposed to heavy infection; the effects of seasonal as opposed to perennial transmission; and the importance of transplacental transmission of microfilariae or soluble antigens. PMID:3297559

  12. Some unsolved problems in the epidemiology of onchocerciasis.

    PubMed

    Southgate, B A

    1987-01-01

    The descriptive epidemiology of onchocerciasis is well understood in the major foci of infection; a great stimulus to epidemiological research has been the implementation of the first control programme, which led to the eradication of infection in Kenya and, more recently, the vast Onchocerciasis Control Programme in the Volta River Basin of West Africa. However, there are still significant gaps in epidemiological knowledge which hamper the planning of future control programmes and the evaluation of current programmes. The four most important unsolved problems are: the refinement of field diagnostic techniques to identify skin microfilariae at the ultra-low densities that will become common in the late stages of vector-control campaigns; the definitive identification of Onchocerca volvulus infective larvae in Simulium species; strain analysis in the field of microfilariae from humans and of developing stages from Simulium, to determine their potential for ocular pathogenicity; determination of the lifespan, or maximum fecundity span, of adult female O. volvulus after the interruption of transmission. Three other unsolved problems are of enormous interest epidemiologically, although less urgent in practical importance. They are the identification of factors causing severe disease as opposed to heavy infection; the effects of seasonal as opposed to perennial transmission; and the importance of transplacental transmission of microfilariae or soluble antigens.

  13. Southern Africa

    Atmospheric Science Data Center

    2013-04-16

    article title:  Southern Africa     View larger JPEG image ... visibility of smoke plumes and haze. The southern tip of South Africa is at the bottom of the image, and Zambia is at the top. ... MISR Team. Aug 25, 2000 - South Africa to Zambia including the Okavango Delta. project:  ...

  14. Neotectonic faults and stress field in the East African Rift System around the Tanzanian Craton - A contribution to the seismotectonic map of Africa

    NASA Astrophysics Data System (ADS)

    Delvaux, Damien; Macheyeki, Athanas Simon; Fernandes, Rui-Manuel; Ayele, Atalay; Meghraoui, Mustapha

    2015-04-01

    As a contribution to the UNESCO-IUGS IGCP 601 project "Seismotectonics and seismic hazards in Africa" and in preparation of the Seismotectonic Map of Africa, we compiled the neotectonic faults related to the East African Rift System around the Tanzanian craton. The initial aim was to identify and map the potentially active faults. Faults are usually defined as active when they show seismogenic displacement during the last 10,000 to 100,000 years, generally on the basis of paleoseismic investigation. In East Africa, however, very few faults have been studied by paleoseismic techniques and even fewer have known historical seismic activation. To address this issue, we mapped faults that show morphological indications of displacement. We used the SRTM DTM (90 and 30 m when available to us), with artificial shading as basis for identify neotectonic faults, in combination with existing data from geological maps, publications and reports, complemented by our own field observations. Thermal springs often occur along tectonically active faults. We use them to distinguish present-day faulting from other mapped faults as they are in most cases structurally controlled. In parallel, we used also the available focal mechanisms and geological fault-slip data to constrain the stress second-order stress field (at the scale of rift segments) and locally also the third-order stress field (at the local scale). All these elements are combined and compared with existing kinematic models for the East African Rift based on earthquake slip vectors, GPS measurements and geologic indicators. The comparison evidences some local discrepancies between the stress field and the direction of opening, probably due to the interactions between different rift segments, as in the Rukwa rift, Mbeya southern junction between the eastern and western rift branches, and in the Manyara-Natron area.

  15. Levelling or Playing the Field? The Politics of Access to University Education in Post-Apartheid South Africa.

    ERIC Educational Resources Information Center

    Naidoo, Rajani

    1998-01-01

    Provides an account of access policies in relation to university education in South Africa by analyzing the practices surrounding the report "A Framework for Transformation." Argues that the repositioning of equity, economic development, and academic standards within the arena of the National Commission on Higher Education has shaped access…

  16. A new velocity field for Africa from combined GPS and DORIS space geodetic Solutions: Contribution to the definition of the African reference frame (AFREF)

    NASA Astrophysics Data System (ADS)

    Saria, E.; Calais, E.; Altamimi, Z.; Willis, P.; Farah, H.

    2013-04-01

    We analyzed 16 years of GPS and 17 years of Doppler orbitography and radiopositioning integrated by satellite (DORIS) data at continuously operating geodetic sites in Africa and surroundings to describe the present-day kinematics of the Nubian and Somalian plates and constrain relative motions across the East African Rift. The resulting velocity field describes horizontal and vertical motion at 133 GPS sites and 9 DORIS sites. Horizontal velocities at sites located on stable Nubia fit a single plate model with a weighted root mean square residual of 0.6 mm/yr (maximum residual 1 mm/yr), an upper bound for plate-wide motions and for regional-scale deformation in the seismically active southern Africa and Cameroon volcanic line. We confirm significant southward motion ( ˜ 1.5 mm/yr) in Morocco with respect to Nubia, consistent with earlier findings. We propose an updated angular velocity for the divergence between Nubia and Somalia, which provides the kinematic boundary conditions to rifting in East Africa. We update a plate motion model for the East African Rift and revise the counterclockwise rotation of the Victoria plate and clockwise rotation of the Rovuma plate with respect to Nubia. Vertical velocities range from - 2 to +2 mm/yr, close to their uncertainties, with no clear geographic pattern. This study provides the first continent-wide position/velocity solution for Africa, expressed in International Terrestrial Reference Frame (ITRF2008), a contribution to the upcoming African Reference Frame (AFREF). Except for a few regions, the African continent remains largely under-sampled by continuous space geodetic data. Efforts are needed to augment the geodetic infrastructure and openly share existing data sets so that the objectives of AFREF can be fully reached.

  17. Mitochondrial DNA and Cancer Epidemiology Workshop

    Cancer.gov

    A workshop to review the state-of-the science in the mitochondrial DNA field and its use in cancer epidemiology, and to develop a concept for a research initiative on mitochondrial DNA and cancer epidemiology.

  18. Constraints on lithospheric structure from satellite potential field data: Africa and Asia. Analysis and interpretation of MAGSAT anomalies over North Africa

    NASA Technical Reports Server (NTRS)

    Phillips, R. J.

    1986-01-01

    Crustal anomaly detection with MAGSAT data is frustrated by the inherent resolving power of the data and by contamination from the external and core fields. The quality of the data might be tested by modeling specific tectonic features which produce anomalies that fall within the proposed resolution and crustal amplitude capabilities of the MAGSAT fields. To test this hypothesis, the north African hotspots associated with Ahaggar, Tibestia and Darfur have been modeled as magnetic induction anomalies due solely to shallower depth to the Curie isotherm surface beneath these features. The MAGSAT data were reduced by subtracting the external and core fields to isolate the scalar and vertical component crustal signals. The predicted model magnetic signal arising from the surface topography of the uplift and the Curie isotherm surface was calculated at MAGSAT altitudes by the Fourier transform technique modified to allow for variable magnetization. In summary it is suggested that the region beneath Ahaggar is associated with a strong thermal anomaly and the predicted anomaly best fits the associated MAGSAT anomaly if the African plate is moving in a northeasterly direction.

  19. Incidence of WHO Stage 3 and 4 Events, Tuberculosis, and Mortality in Untreated, HIV-Infected Children Enrolling in Care Before 1 Year of Age: An Iedea (International Epidemiologic Databases To Evaluate AIDS) East Africa Regional Analysis

    PubMed Central

    Ciaranello, Andrea; Lu, Zhigang; Ayaya, Samuel; Losina, Elena; Musick, Beverly; Vreeman, Rachel; Freedberg, Kenneth A.; Abrams, Elaine J.; Dillabaugh, Lisa; Doherty, Katie; Ssali, John; Yiannoutsos, Constantin T.; Wools-Kaloustian, Kara

    2014-01-01

    Background Few studies have reported CD4%- and age-stratified rates of WHO Stage 3 (WHO3) events, WHO Stage 4 (WHO4) events, tuberculosis (TB), and mortality in HIV-infected infants before initiation of antiretroviral therapy (ART). Methods HIV-infected children enrolled before 1 year of age in the International Epidemiologic Databases to Evaluate AIDS (IeDEA) East Africa region (10/01/2002-11/30/2008) were included. We estimated incidence rates of earliest clinical event (WHO3, WHO4, and TB), prior to ART initiation per local guidelines, stratified by current age (< or ≥6 months) and current CD4% (<15%, 15–24%, ≥25%). CD4%-stratified mortality rates were estimated separately for children who did not experience a clinical event (“background” mortality) and for children who experienced an event, including “acute” mortality (≤30 days post-event) and “later” mortality (>30 days post-event). Results Among 847 children (median enrollment age: 4.8 months; median pre-ART follow-up: 10.8 months; 603 (71%) with ≥1 CD4% recorded), event rates were comparable for those aged <6 and ≥6 months. Current CD4% was associated with risk of WHO4 events for children <6 months old, and with all evaluated events for children ≥6 months old (p<0.05). “Background” mortality was 3.7–8.4/100py. “Acute” mortality (≤30 days post-event) was 33.8/100py (after TB) and 41.1/100py (after WHO3 or WHO4). “Later” mortality (>30 days post-event) ranged by CD4% from 4.7–29.1/100py. Conclusions In treatment-naïve, HIV-infected infants, WHO3, WHO4, and TB events were common before and after 6 months of age and led to substantial increases in mortality. Early infant HIV diagnosis and treatment are critically important, regardless of CD4%. PMID:24378935

  20. Epidemiologic study of electric utility workers exposed to magnetic fields. Volume 2: Extended results, tables, and peer-reviewed manuscripts. Final report

    SciTech Connect

    Savitz, D.A.; Loomis, D.P.

    1996-06-01

    Previous epidemiologic studies, including several focused on electric utility workers, have suggested that occupational exposure to magnetic fields may be associated with increased leukemia and brain cancer risk. This study examined mortality, especially leukemia and brain cancer mortality, among nearly 139,000 men employed at five US electric utility companies between 1950 and 1988. The study included a detailed assessment of magnetic field exposure accumulated over each worker`s career, as well as estimates of concomitant exposures to solvents and PCBs. The electric utility workers` mortality from all causes and from all types of cancer combined was substantially below that of the US male population. Analysis of mortality patterns in relation to magnetic field exposure supported the hypothesis that magnetic field exposure increases the risk of brain cancer. Brain cancer risk increased with increasing magnetic field exposure, and was highest among those with the highest cumulative exposure. The study did not support the hypothesized association between magnetic field exposure and leukemia. Volume 1 of this report contains principals results, an in-depth presentation of study methods, detailed tables of results, conclusions, and interpretation of results. Volume 2 contains additional tables of results and other peer-reviewed manuscripts.

  1. Validation of Rapid Point-of-Care (POC) Tests for Detection of Hepatitis B Surface Antigen in Field and Laboratory Settings in the Gambia, Western Africa

    PubMed Central

    Njai, Harr Freeya; Shimakawa, Yusuke; Sanneh, Bakary; Ferguson, Lynne; Ndow, Gibril; Mendy, Maimuna; Sow, Amina; Lo, Gora; Toure-Kane, Coumba; Tanaka, Junko; Taal, Makie; D'alessandro, Umberto; Njie, Ramou; Thursz, Mark

    2015-01-01

    Hepatitis B virus (HBV) infection is a leading cause of death in sub-Saharan Africa (SSA). Point-of-care tests for hepatitis B surface antigen (HBsAg) could be an ideal tool for a large-scale HBV screening/treatment program in SSA. Using data from the PROLIFICA (Prevention of Liver Fibrosis and Cancer in Africa) program, we conducted a cross-sectional study to assess the diagnostic accuracy of three point-of-care tests (Determine, Vikia, and Espline) for the detection of HBsAg in the field or a laboratory setting in the Gambia. In the field, we used finger-prick whole blood for the Determine and Vikia tests and dried blood spots for the reference standard test (AxSYM HBsAg enzyme-linked immunosorbent assay [ELISA]). In the laboratory we used serum for the Determine, Espline, and reference test (Architect chemiluminescent microparticle immunoassay). Of 773 participants recruited at the community and 227 known chronic HBV carriers (1,000 subjects in total), 293 were positive for HBsAg. The sensitivity and specificity of the Determine test were 88.5% and 100% in the field and 95.3% and 93.3% in the laboratory setting, respectively. The sensitivity and specificity were 90.0% and 99.8% for the Vikia test (in the field) and 93.9% and 94.7% for the Espline test (in the laboratory). There was no evidence that one kit was better than another. Most of the patients with false-negative results (18/19) were classified as inactive chronic carriers. In summary, the three point-of-care tests had acceptable ranges of diagnostic accuracy. These tests may represent accurate, rapid, and inexpensive alternatives to serology testing for the screening of HBV infection at field level in SSA. PMID:25631805

  2. Determination of acaricide resistance in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) field populations of Argentina, South Africa, and Australia with the Larval Tarsal Test.

    PubMed

    Lovis, L; Reggi, J; Berggoetz, M; Betschart, B; Sager, H

    2013-03-01

    Infestations with ticks have an important economic impact on the cattle industry worldwide and resistance to acaricides has become a widespread phenomenon. To optimize their treatment strategy, farmers need to know if and against which classes potential acaricide-resistance does occur. Bioassays are used to assess the resistance level and pattern of Rhipicephalus (Boophilus) microplus populations. The objective of the current study was to assess the susceptibility of field populations originating from Argentina (8), South Africa (3), and Australia (2) using the Larval Tarsal Test. Nine acaricidal compounds from five major classes were tested: organosphosphates, synthetic pyrethroids (SP), macrocyclic lactones, phenylpyrazols, and amidines. The resistance ratios at concentrations inducing 50 and 90% mortality were used to detect established and emerging resistance. This study confirmed the newly reported presence of amitraz resistance in populations from Argentina In addition, resistance to SP appeared to be widespread (88%) in the Argentinean farms, which had been selected based on the observation of lack of treatment efficacy by farmers. In South Africa one of the three populations was found to be resistant to SP and to a phenylpyrazol compound (pyriprol). Furthermore, resistance to organosphosphates and SP was observed in Australia. Finally, the Larval Tarsal Test proved to be a suitable test to evaluate the susceptibility of R. microplus field populations to the most relevant acaricidal classes. PMID:23540121

  3. The new epidemiology of nephrolithiasis.

    PubMed

    Shoag, Jonathan; Tasian, Greg E; Goldfarb, David S; Eisner, Brian H

    2015-07-01

    Historically nephrolithiasis was considered a disease of dehydration and abnormal urine composition. However, over the past several decades, much has been learned about the epidemiology of this disease and its relation to patient demographic characteristics and common systemic diseases. Here we review the latest epidemiologic studies in the field. PMID:26088071

  4. Epidemiological fingerprinting of Enterobacter cloacae by small-fragment restriction endonuclease analysis and pulsed-field gel electrophoresis of genomic restriction fragments.

    PubMed Central

    Haertl, R; Bandlow, G

    1993-01-01

    A cluster of infections caused by Enterobacter cloacae was observed among preterm neonates in a neonatal intensive care unit (NICU) of a pediatric hospital in Osnabrück, Germany. The presence of similar antimicrobial susceptibility patterns among the bacterial isolates prompted an investigation to determine whether a limited spread of a single strain existed. All 12 E. cloacae isolates from the NICU and 50 nonrelated strains were fingerprinted by small-fragment restriction endonuclease analysis (SF-REA) of EcoRI DNA digests. Selected isolates were further characterized by pulsed-field gel electrophoresis (PFGE) of NotI- or XbaI-generated genomic restriction fragments. Epidemiologically unrelated strains were clearly discriminated by both methods. Results achieved by SF-REA and PFGE revealed that of the 12 isolates from the NICU, 11 belonged to the same genotypic cluster. Since all reagents and equipment for both techniques are commercially available, DNA fingerprinting by SF-REA or PFGE is proposed as a useful tool in the microbiology laboratory for investigating the epidemiological relatedness of E. cloacae strains of clinical and environmental origin. Images PMID:8093251

  5. Endodontic Epidemiology

    PubMed Central

    Shahravan, Arash; Haghdoost, Ali Akbar

    2014-01-01

    Epidemiology is the study of disease distribution and factors determining or affecting it. Likewise, endodontic epidemiology can be defined as the science of studying the distribution pattern and determinants of pulp and periapical diseases; specially apical periodontitis. Although different study designs have been used in endodontics, researchers must pay more attention to study designs with higher level of evidence such as randomized clinical trials. PMID:24688577

  6. The Feasibility of Canine Rabies Elimination in Africa: Dispelling Doubts with Data

    PubMed Central

    Lembo, Tiziana; Hampson, Katie; Kaare, Magai T.; Ernest, Eblate; Knobel, Darryn; Kazwala, Rudovick R.; Haydon, Daniel T.; Cleaveland, Sarah

    2010-01-01

    Background Canine rabies causes many thousands of human deaths every year in Africa, and continues to increase throughout much of the continent. Methodology/Principal Findings This paper identifies four common reasons given for the lack of effective canine rabies control in Africa: (a) a low priority given for disease control as a result of lack of awareness of the rabies burden; (b) epidemiological constraints such as uncertainties about the required levels of vaccination coverage and the possibility of sustained cycles of infection in wildlife; (c) operational constraints including accessibility of dogs for vaccination and insufficient knowledge of dog population sizes for planning of vaccination campaigns; and (d) limited resources for implementation of rabies surveillance and control. We address each of these issues in turn, presenting data from field studies and modelling approaches used in Tanzania, including burden of disease evaluations, detailed epidemiological studies, operational data from vaccination campaigns in different demographic and ecological settings, and economic analyses of the cost-effectiveness of dog vaccination for human rabies prevention. Conclusions/Significance We conclude that there are no insurmountable problems to canine rabies control in most of Africa; that elimination of canine rabies is epidemiologically and practically feasible through mass vaccination of domestic dogs; and that domestic dog vaccination provides a cost-effective approach to the prevention and elimination of human rabies deaths. PMID:20186330

  7. Aboveground biomass estimation using SAR-optical (Lidar, RapidEye) and field inventory datasets in Skukuza, Kruger National Park in South Africa

    NASA Astrophysics Data System (ADS)

    Onyango Odipo, Victor; Hüttich, Christian; Luck, Wolfgang; Schmullius, Christiane

    2015-04-01

    African savanna covers approximately two-thirds of sub-saharan Africa, playing important roles as a carbon pool, habitat for mankind and wildlife, source of livelihood, an important tropical climate modifier, among other ecological roles. Sub-saharan Africa alone accounts for 25% of the tropical aboveground carbon stock (193 Gt C). Global and national level AGB estimates rely on extrapolations with regression models from few field inventories, leading in some cases, up to 100% uncertainty. Remote sensing has proven to provide reliable vegetation structural mapping, given the high spatial and temporal resolution allowing datasets to be availed in areas where ground based inventories are infeasible due to time and financial constraints. The availability of freely accessible optical remotely-sensed datasets has made this feat attainable. However, the heterogeneity of tropical savannas (co-existence of trees and grasses), coupled with erratic rainfall events and atmospheric clouds and aerosol in the tropics has made it difficult to extract biophysical properties of the savannas by solely using optical datasets. This has necessitated an assessment of synergies between active and passive remotely sensed datasets to benefit from the complementarities. In this study we assess the extent to which multi-level sub-centimeter Unmanned Aerial Vehicle (UAV) Lidar, high resolution RapidEye and microwave (ALOS PALSAR L-band and Sentinel-1 C-band) remotely sensed datasets can be used together with tree census datasets to estimate AGB within the complex southern Africa savanna ecosystem. A random forest (RF) regression model is produced which relates the Lidar canopy-height metrics (CHM) with both synthetic aperture radar (SAR) and high resolution RapidEye datasets. As a validation, we compare our results with both national and global level ABG estimates.

  8. HIV prevention in action on the football field: the WhizzKids United program in South Africa.

    PubMed

    Balfour, Louise; Farrar, Thomas; McGilvray, Marcus; Wilson, Douglas; Tasca, Giorgio A; Spaans, Johanna N; Mathews, Catherine; Maziya, Lungile; Khanyile, Siphosihle; Dalgleish, Tracy L; Cameron, William D

    2013-07-01

    The Africaid Trust is a grassroots South African non-profit organization that engages youth in HIV prevention by harnessing the popularity of football (i.e. soccer). WhizzKids United, the organization's primary program, operates a 12-week program in elementary schools in Pietermaritzburg, South Africa, which aims to impart knowledge and life skills critical to HIV prevention. The goal of this research was to compare elementary school youth who received the program to youth who only received traditional classroom-based HIV education on health behaviors and HIV-related knowledge and stigma. A secondary objective was to evaluate HIV knowledge, sexual behaviors, attitudes towards HIV and health care seeking behaviors among South African youth in grades 9-12. Elementary students who participated in the program reported greater HIV knowledge and lower HIV stigma (p < .001) than those who had not. The majority of youth in grades 9-12 report having sexual relations (55.6%), despite low levels of HIV testing (29.9%) in this high HIV prevalence region of South Africa. The results highlight the importance of supporting community-based HIV educational initiatives that engage high-risk youth in HIV prevention and the need for youth-friendly health services.

  9. Mansonella perstans filariasis in Africa.

    PubMed

    Simonsen, Paul E; Onapa, Ambrose W; Asio, Santa Maria

    2011-09-01

    Mansonella perstans is a vector-borne human filarial nematode, transmitted by tiny blood-sucking flies (biting midges). It is widespread in many parts of Sub-Saharan Africa and also occurs in parts of Central and South America. Despite the commonness of this parasite very few studies have been carried out on its epidemiology and on the morbidity resulting from it, and only few thorough drug trials have been conducted to look for effective and suitable drugs and drug regimens for treatment and control. Here, we review currently available knowledge on M. perstans infections in Africa, including documented aspects of biology, vectors, transmission, diagnosis, epidemiology, morbidity and treatment. It is concluded that there is an urgent need for more research on this widespread but greatly neglected infection in order to properly assess its public health significance and as a background for identifying and recommending optimal means and strategies for treatment and control. PMID:20152790

  10. Metabolomics and Epidemiology Working Group

    Cancer.gov

    The Metabolomics and Epidemiology (MetEpi) Working Group promotes metabolomics analyses in population-based studies, as well as advancement in the field of metabolomics for broader biomedical and public health research.

  11. Field synopsis and meta-analyses of genetic epidemiological evidence for Kashin-Beck disease, an endemic osteoarthropathy in China.

    PubMed

    Yang, Lei; Zhao, Guang-Hui; Liu, Huan; Wang, Xi; Guo, Xiong; Lammi, Mikko J

    2016-10-01

    Kashin-Beck disease (KBD) is a chronic degenerative osteoarthropathy with unclear etiology. To provide current evidence supporting a genetic predisposition for KBD, we conducted a systematic review and meta-analysis of published literature on the genetic epidemiology of KBD. The PubMed, China National Knowledge Infrastructure and Wan Fang Data were searched up to August 2015 for articles published in English and Chinese. Genome-wide and exome sequencing, linkage, and case-control association studies for any genetic variants associated with KBD were included. Meta-analysis was performed for all single nucleotide polymorphisms (SNPs) that were evaluated in two or more studies. The effect size was summarized as odds ratios (ORs) with 95 % confidence intervals (CIs) by fixed and random effects models. A total of 24 articles were systematically reviewed. Eleven short tandem repeats on chromosomes 2, 11 and 12, 34 SNPs in 12 genes, as well as copy number variant 452 were identified as KBD susceptibility factors in individual studies. The meta-analysis of the GPX1 rs1050450, DIO2 rs225014, TrxR2 rs5748469 and HLA-DRB1 rs7745040 failed to reveal any associations with KBD. However, the meta-analysis of HLA-DRB1 rs9275295 allele A was associated with KBD (OR = 1.737, 95 % CI: 1.002-3.012). In addition, seven haplotypes in GPX1, GPX4, HLA-DRB1 and GDF5 genes also showed significant associations with KBD. In conclusions, our study could identify a number of genetic markers associated with KBD. However, the evidence does not currently support a strong association between the specific variants and KBD because of the limited number of studies, and in the future, more rigorous studies are needed to confirm KBD's links with these variants. PMID:27256326

  12. Polygenic Epidemiology

    PubMed Central

    2016-01-01

    ABSTRACT Much of the genetic basis of complex traits is present on current genotyping products, but the individual variants that affect the traits have largely not been identified. Several traditional problems in genetic epidemiology have recently been addressed by assuming a polygenic basis for disease and treating it as a single entity. Here I briefly review some of these applications, which collectively may be termed polygenic epidemiology. Methodologies in this area include polygenic scoring, linear mixed models, and linkage disequilibrium scoring. They have been used to establish a polygenic effect, estimate genetic correlation between traits, estimate how many variants affect a trait, stratify cases into subphenotypes, predict individual disease risks, and infer causal effects using Mendelian randomization. Polygenic epidemiology will continue to yield useful applications even while much of the specific variation underlying complex traits remains undiscovered. PMID:27061411

  13. [Occupational epidemiology].

    PubMed

    Ahrens, W; Behrens, T; Mester, B; Schmeisser, N

    2008-03-01

    The aim of occupational epidemiology is to describe workplace-related diseases and to identify their underlying causes. Its primary goal is to protect workers from hazardous effects of the working process by applying work-related primary and secondary prevention measures. To assess health risks different study designs and a wide array of complex study instruments and methods are frequently employed that cannot be replaced by toxicological investigations. This paper primarily addresses health risks by agent exposures. In this context a central task of occupational epidemiology is careful assessment of exposure. Different data sources, such as work site measurements, register data, archive material, experts' opinion, and the workers' personal estimates of exposure may be used during this process. In addition, biological markers can complement exposure assessment. Since thorough occupational epidemiologic studies allow assessment of disease risks under realistic exposure conditions, their results should be more frequently used to derive workplace-related threshold limit values. PMID:18311483

  14. Polygenic Epidemiology.

    PubMed

    Dudbridge, Frank

    2016-05-01

    Much of the genetic basis of complex traits is present on current genotyping products, but the individual variants that affect the traits have largely not been identified. Several traditional problems in genetic epidemiology have recently been addressed by assuming a polygenic basis for disease and treating it as a single entity. Here I briefly review some of these applications, which collectively may be termed polygenic epidemiology. Methodologies in this area include polygenic scoring, linear mixed models, and linkage disequilibrium scoring. They have been used to establish a polygenic effect, estimate genetic correlation between traits, estimate how many variants affect a trait, stratify cases into subphenotypes, predict individual disease risks, and infer causal effects using Mendelian randomization. Polygenic epidemiology will continue to yield useful applications even while much of the specific variation underlying complex traits remains undiscovered. PMID:27061411

  15. [Epidemiology of tuberculosis].

    PubMed

    Mjid, M; Cherif, J; Ben Salah, N; Toujani, S; Ouahchi, Y; Zakhama, H; Louzir, B; Mehiri-Ben Rhouma, N; Beji, M

    2015-01-01

    Tuberculosis is a contagious disease caused by Mycobacterium tuberculosis. It represents, according to World Health Organization (WHO), one of the most leading causes of death worldwide. With nearly 8 million new cases each year and more than 1 million deaths per year, tuberculosis is still a public health problem. Despite of the decrease in incidence, morbidity and mortality remain important partially due to co-infection with human immunodeficiency virus and emergence of resistant bacilli. All WHO regions are not uniformly affected by TB. Africa's region has the highest rates of morbidity and mortality. The epidemiological situation is also worrying in Eastern European countries where the proportion of drug-resistant tuberculosis is increasing. These regional disparities emphasize to develop screening, diagnosis and monitoring to the most vulnerable populations. In this context, the Stop TB program, developed by the WHO and its partner's, aims to reduce the burden of disease in accordance with the global targets set for 2015.

  16. Neisseria meningitidis Serogroup X in Sub-Saharan Africa

    PubMed Central

    Agnememel, Alain; Hong, Eva; Giorgini, Dario; Nuñez-Samudio, Viginia; Deghmane, Ala-Eddine

    2016-01-01

    The epidemiology of meningococcal disease varies by geography and time. Whole-genome sequencing of Neisseria meningitidis serogroup X isolates from sub-Saharan Africa and Europe showed that serogroup X emergence in sub-Saharan Africa resulted from expansion of particular variants within clonal complex 181. Virulence of these isolates in experimental mouse models was high. PMID:26982628

  17. NeuroAIDS in Africa

    PubMed Central

    Robertson, Kevin; Liner, Jeff; Hakim, James; Sankalé, Jean-Louis; Grant, Igor; Letendre, Scott; Clifford, David; Diop, Amadou Gallo; Jaye, Assan; Kanmogne, Georgette; Njamnshi, Alfred; Langford, T. Dianne; Gemechu Weyessa, Tufa; Wood, Charles; Banda, Mwanza; Hosseinipour, Mina; Sacktor, Ned; Nakasuja, Noeline; Bangirana, Paul; Paul, Robert; Joska, John; Wong, Joseph; Boivin, Michael; Holding, Penny; Kammerer, Betsy; Van Rie, Annelies; Ive, Prudence; Nath, Avindra; Lawler, Kathy; Adebamowo, Clement; Royal, Walter; Joseph, Jeymohan

    2013-01-01

    In July 2009, the Center for Mental Health Research on AIDS at the National Institute of Mental Health organized and supported the meeting “NeuroAIDS in Africa.” This meeting was held in Cape Town, South Africa, and was affiliated with the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention. Presentations began with an overview of the epidemiology of HIV in sub-Saharan Africa, the molecular epidemiology of HIV, HIV-associated neurocognitive disorders (HANDs), and HAND treatment. These introductory talks were followed by presentations on HAND research and clinical care in Botswana, Cameroon, Ethiopia, The Gambia, Kenya, Malawi, Nigeria, Senegal, South Africa, Uganda, and Zambia. Topics discussed included best practices for assessing neurocognitive disorders, patterns of central nervous system (CNS) involvement in the region, subtype-associated risk for HAND, pediatric HIV assessments and neurodevelopment, HIV-associated CNS opportunistic infections and immune reconstitution syndrome, the evolving changes in treatment implementation, and various opportunities and strategies for NeuroAIDS research and capacity building in the region. PMID:20500018

  18. Epidemiological causality.

    PubMed

    Morabia, Alfredo

    2005-01-01

    Epidemiological methods, which combine population thinking and group comparisons, can primarily identify causes of disease in populations. There is therefore a tension between our intuitive notion of a cause, which we want to be deterministic and invariant at the individual level, and the epidemiological notion of causes, which are invariant only at the population level. Epidemiologists have given heretofore a pragmatic solution to this tension. Causal inference in epidemiology consists in checking the logical coherence of a causality statement and determining whether what has been found grossly contradicts what we think we already know: how strong is the association? Is there a dose-response relationship? Does the cause precede the effect? Is the effect biologically plausible? Etc. This approach to causal inference can be traced back to the English philosophers David Hume and John Stuart Mill. On the other hand, the mode of establishing causality, devised by Jakob Henle and Robert Koch, which has been fruitful in bacteriology, requires that in every instance the effect invariably follows the cause (e.g., inoculation of Koch bacillus and tuberculosis). This is incompatible with epidemiological causality which has to deal with probabilistic effects (e.g., smoking and lung cancer), and is therefore invariant only for the population.

  19. West Africa

    Atmospheric Science Data Center

    2013-04-16

    ... article title:  Hazy and Dusty Skies over Western Africa     View Larger Image ... the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the ...

  20. South Africa

    Atmospheric Science Data Center

    2013-04-16

    article title:  Red Tide Strands South African Rock Lobsters     ... and on atmospheric and oceanic conditions. At Elands Bay in South Africa's Western Cape province, about 1000 tons of rock lobsters beached ...

  1. Personality and Personality Disorders in Urban and Rural Africa: Results from a Field Trial in Burkina Faso

    PubMed Central

    Rossier, Jérôme; Ouedraogo, Abdoulaye; Dahourou, Donatien; Verardi, Sabrina; Meyer de Stadelhofen, Franz

    2013-01-01

    When conducting research in different cultural settings, assessing measurement equivalence is of prime importance to determine if constructs and scores can be compared across groups. Structural equivalence implies that constructs have the same meaning across groups, metric equivalence implies that the metric of the scales remains stable across groups, and full scale or scalar equivalence implies that the origin of the scales is the same across groups. Several studies have observed that the structure underlying both normal personality and personality disorders (PDs) is stable across cultures. Most of this cross-cultural research was conducted in Western and Asian cultures. In Africa, the few studies were conducted with well-educated participants using French or English instruments. No research was conducted in Africa with less privileged or preliterate samples. The aim of this research was to study the structure and expression of normal and abnormal personality in an urban and a rural sample in Burkina Faso. The sample included 1,750 participants, with a sub-sample from the urban area of Ouagadougou (n = 1,249) and another sub-sample from a rural village, Soumiaga (n = 501). Most participants answered an interview consisting of a Mooré language adaptation of the Revised NEO Personality Inventory and of the International Personality Disorders Examination. Mooré is the language of the Mossi ethnic group, and the most frequently spoken local language in Burkina Faso. A sub-sample completed the same self-report instruments in French. Demographic variables only had a small impact on normal and abnormal personality traits mean levels. The structure underlying normal personality was unstable across regions and languages, illustrating that translating a complex psychological inventory into a native African language is a very difficult task. The structure underlying abnormal personality and the metric of PDs scales were stable across regions. As scalar equivalence

  2. Namib Desert, Namibia, Africa

    NASA Technical Reports Server (NTRS)

    1990-01-01

    One of the driest regions on Earth, the Namib Desert, Namibia, Africa (23.0N, 15.0E) lies adjacent to the Atlantic coast but the upwelling oceanic water causes a very stable rainless atmosphere. The few local inland rivers do not reach the sea but instead, appear as long indentations where they penetrate the dune fields and end as small dry lakes. The vast dune fields are the result of sands deposited over millions of years by the stream flow.

  3. Namib Desert, Namibia, Africa

    NASA Technical Reports Server (NTRS)

    1990-01-01

    One of the driest regions on Earth, the Namib Desert, Namibia, Africa (23.0N, 15.0E) lies adjacent to the Atlantic coast but upwelling oceanic water causes a very stable rainless atmosphere. The few local inland rivers do not reach the sea but instead appear as long indentations where rivers penetrate the dune fields and end as small dry lakes. The vast dune fields are the result of sands deposited over millions of years by the stream flow.

  4. Hantaviruses in Africa.

    PubMed

    Witkowski, Peter T; Klempa, Boris; Ithete, Ndapewa L; Auste, Brita; Mfune, John K E; Hoveka, Julia; Matthee, Sonja; Preiser, Wolfgang; Kruger, Detlev H

    2014-07-17

    This paper summarizes the progress in the search for hantaviruses and hantavirus infections in Africa. After having collected molecular evidence of an indigenous African hantavirus in 2006, an intensive investigation for new hantaviruses has been started in small mammals. Various novel hantaviruses have been molecularly identified not only in rodents but also in shrews and bats. In addition, the first African hantavirus, Sangassou virus, has been isolated and functionally characterized in cell culture. Less is known about the ability of these hantaviruses to infect humans and to cause diseases. To date, no hantavirus genetic material could be amplified from patients' specimens collected in Africa. Serological studies in West Africa, based on a battery of screening and confirmatory assays, led to the detection of hantavirus antibodies in the human population and in patients with putative hantavirus disease. In addition to this overview, we present original data from seroepidemiological and field studies conducted in the Southern part of Africa. A human seroprevalence rate of 1.0% (n=1442) was detected in the South African Cape Region whereas no molecular evidence for the presence of hantavirus was found in 2500 small animals trapped in South Africa and Namibia.

  5. Hantaviruses in Africa.

    PubMed

    Witkowski, Peter T; Klempa, Boris; Ithete, Ndapewa L; Auste, Brita; Mfune, John K E; Hoveka, Julia; Matthee, Sonja; Preiser, Wolfgang; Kruger, Detlev H

    2014-07-17

    This paper summarizes the progress in the search for hantaviruses and hantavirus infections in Africa. After having collected molecular evidence of an indigenous African hantavirus in 2006, an intensive investigation for new hantaviruses has been started in small mammals. Various novel hantaviruses have been molecularly identified not only in rodents but also in shrews and bats. In addition, the first African hantavirus, Sangassou virus, has been isolated and functionally characterized in cell culture. Less is known about the ability of these hantaviruses to infect humans and to cause diseases. To date, no hantavirus genetic material could be amplified from patients' specimens collected in Africa. Serological studies in West Africa, based on a battery of screening and confirmatory assays, led to the detection of hantavirus antibodies in the human population and in patients with putative hantavirus disease. In addition to this overview, we present original data from seroepidemiological and field studies conducted in the Southern part of Africa. A human seroprevalence rate of 1.0% (n=1442) was detected in the South African Cape Region whereas no molecular evidence for the presence of hantavirus was found in 2500 small animals trapped in South Africa and Namibia. PMID:24406800

  6. A little bit of Africa in Brazil: ethnobiology experiences in the field of Afro-Brazilian religions.

    PubMed

    Albuquerque, Ulysses Paulino

    2014-01-01

    This essay, which is the fourth in the series "Recollections, Reflections, and Revelations: Ethnobiologists and Their First Time in the Field", is a personal reflection by the researcher on his first field experience with ethnobiology of so called Afro-Brazilian cults. The author recounts his feelings and concerns associated with initial fieldwork. PMID:24467714

  7. A Perspective on Invasive Salmonella Disease in Africa.

    PubMed

    Crump, John A; Heyderman, Robert S

    2015-11-01

    Salmonella enterica is a leading cause of community-acquired bloodstream infection in Africa. The contribution of typhoidal and nontyphoidal Salmonella serovars to invasive disease varies considerably in place and time, even within the same country. Nonetheless, many African countries are now thought to experience typhoid fever incidence >100 per 100,000 per year with approximately 1% of patients dying. Invasive nontyphoidal Salmonella (iNTS) disease was estimated to cause 3.4 million illnesses and 681 316 deaths in 2010, with the most disease in Africa. Antimicrobial drug resistance is a growing problem in S. enterica that threatens to further compromise patient outcomes. Reservoirs for nontyphoidal Salmonella and the predominant routes of transmission for typhoidal and nontyphoidal Salmonella are not well understood in Africa, hampering the design of evidence-based, non-vaccine- and vaccine-based prevention measures. It is difficult to distinguish clinically invasive Salmonella disease from febrile illnesses caused by other pathogens. Blood cultures are the mainstay of laboratory diagnosis, but lack sensitivity due to the low magnitude of bacteremia, do not produce results at point of care, and are not widely available in Africa. Serologic approaches to diagnosis remain inaccurate, and nucleic acid amplification tests are also compromised by low concentrations of bacteria. High-throughput whole-genome sequencing, together with a range of novel analytic pipelines, has provided new insights into the complex pattern of epidemiology, pathogenesis, and host adaptation. Concerted efforts are therefore needed to apply these new tools in the context of high-quality field surveillance to improve diagnosis, patient management, control, and prevention of invasive Salmonella infections in Africa. PMID:26449937

  8. Field-testing of guidance on the appropriate labelling of processed complementary foods for infants and young children in South Africa.

    PubMed

    Sweet, Lara; Jerling, Johann; Van Graan, Averalda

    2013-01-01

    There is a lack of formal guidance from international normative bodies on the appropriate marketing of processed complementary foods. Such guidance is necessary to protect and promote optimal infant and young child feeding practices. The aim of this study was to field-test, in South Africa, the interim guidance provided by the Maternal, Infant and Young Child Nutrition Working Group's Draft Guide for Marketing Complementary Foods as a potential tool for use by manufacturers and national governments for guiding the appropriate labelling (as a subset of appropriate marketing practices) of complementary foods. This guidance was used to develop a checklist of questions and criteria for each possible answer, which was tested using a comprehensive database of labels from products purchased in South Africa from June to August 2011. One hundred and sixty product labels of 35 manufacturers were analysed, none of which complied with all checklist criteria. Fifty-six (35%) labels did not provide an appropriate age of introduction while 37 (23%) used images of infants appearing younger than 6 months. Nineteen (12%) labels suggested a daily ration too large for a breastfed child, and 32 (20%) potentially promote the manufacturer's infant formula. Only 58 (36%) labels were easy to read. The majority (69% and 92%) of labels provided instructions for safe and appropriate preparation/use and storage, respectively. The Draft Guide for Marketing Complementary Foods was found to be a useful tool for guiding the appropriate labelling of complementary foods, although some changes and additions are recommended to improve understanding, ease of use and to minimise the subjective interpretation of the guidance. PMID:23167582

  9. Digital Epidemiology

    PubMed Central

    Salathé, Marcel; Bengtsson, Linus; Bodnar, Todd J.; Brewer, Devon D.; Brownstein, John S.; Buckee, Caroline; Campbell, Ellsworth M.; Cattuto, Ciro; Khandelwal, Shashank; Mabry, Patricia L.; Vespignani, Alessandro

    2012-01-01

    Mobile, social, real-time: the ongoing revolution in the way people communicate has given rise to a new kind of epidemiology. Digital data sources, when harnessed appropriately, can provide local and timely information about disease and health dynamics in populations around the world. The rapid, unprecedented increase in the availability of relevant data from various digital sources creates considerable technical and computational challenges. PMID:22844241

  10. The influence of tillage on field scale water fluxes and maize yields in semi-arid environments: A case study of Potshini catchment, South Africa

    NASA Astrophysics Data System (ADS)

    Kosgei, J. R.; Jewitt, G. P. W.; Kongo, V. M.; Lorentz, S. A.

    Water is a limiting resource to crop production in arid and semi-arid lands (ASALs) and is responsible for substantial yield losses annually. These lands are often occupied by resource poor smallholder rainfed farmers who have little capacity to establish conventional irrigation infrastructure to mitigate recurrent droughts and dry spells. In situ water harvesting techniques in the form of conservation agriculture practices have been identified and promoted as measures that can improve soil water availability and thus enhance crop yields. Land use practices e.g. tillage influences mechanisms of lateral flow, infiltration, storage, redistribution and residence times of water at field scale. Such alterations in flow paths have not been adequately studied in ASALs where small perturbations at field scale upstream of a catchment may have significant effects downstream. Quantifying these fluxes enables better understanding of productive and non-productive water transition processes and thus to evaluate cropping and management systems. On this study the effects of tillage on water fluxes, soil physical properties and maize ( Zea mays L.) yields were examined at three sites in the Potshini catchment, South Africa. Measurements were made on plots under no-till ( NT) and conventional till ( CT) practices. Seasonal analysis indicated that nearly twice as much runoff was generated from CT treatments when compared to NT plots. However, this was not the case at the beginning of the season. The moisture content in the root zone was significantly higher in NT treatments. Maize yield was also higher in NT compared to CT plots.

  11. [Significance of the transference-countertransference constellation in motivation for participation in an epidemiologic field study of psychogenic disorders: a report of experiences].

    PubMed

    Sollors-Mossler, B; Reister, G

    1992-01-01

    The present article deals mainly with problems arising from the motivation of individuals for the participation in an epidemiological field study and their solutions on the basis of psychological-psychiatric findings. Subsequent to a more detailed survey of the research project in question formal and technical aspects of the motivational efforts (home visits, phone contacts) which had to be performed by the research group are mentioned. In the following the authors focus on the scientific concepts and orientations of their motivation work including the specific attention paid to the constellation of transference and countertransference. Particular importance is attributed to the presentation of several case studies which illustrate the influence of different psychoanalytical character traits on the motivational process. Finally the authors concentrate on specific problems regarding the sex of the probands as well as on their experiences with so-called hesitators i.e. individuals who for a longer period of time cannot decide whether to participate in the study or not.

  12. Epidemiological analysis of Salmonella enterica Enteritidis isolates in Japan by phage-typing and pulsed-field gel electrophoresis.

    PubMed Central

    Terajima, J.; Nakamura, A.; Watanabe, H.

    1998-01-01

    Salmonella enterica serotype Enteritidis isolates of phage types (PTs) PT1, PT4, PT13a and PT22 derived from sporadic cases and outbreaks of food poisoning in Japan during 1994 and 1995 were analysed by pulsed-field gel electrophoresis (PFGE). While PT1 strains from 5 different outbreaks showed 14 PFGE patterns, 5 PFGE patterns were observed among PT4 isolates from 5 different outbreaks and 6 independent isolates from imported chicken. Interestingly, 8 out of 9 PT4 strains associated with foreign travel to Southeast Asia were indistinguishable in PFGE pattern from 5 independent isolates of imported chicken from England. Although both PT13a and PT22 were first reported in Japan in 1994, PT22 showed various PFGE patterns compared to PT13a which had the same pattern within an outbreak, unlike PT1. These results could indicate that multiple clonal lines of PT1 and PT22 had already spread while relatively fewer clonal lines of PT4 and PT13a might exist in Japan. PMID:9692599

  13. Cholera outbreaks in Africa.

    PubMed

    Mengel, Martin A; Delrieu, Isabelle; Heyerdahl, Leonard; Gessner, Bradford D

    2014-01-01

    an infectious dose of Vibrio cholerae and on the virulence of the implicated strain. Cholera transmission can then be amplified by several factors including contamination of human water- or food sources; climate and extreme weather events; political and economic crises; high population density combined with poor quality informal housing and poor hygiene practices; spread beyond a local community through human travel and animals, e.g., water birds. At an individual level, cholera risk may increase with decreasing immunity and hypochlorhydria, such as that induced by Helicobacter pylori infection, which is endemic in much of Africa, and may increase individual susceptibility and cholera incidence. Since contaminated water is the main vehicle for the spread of cholera, the obvious long-term solution to eradicate the disease is the provision of safe water to all African populations. This requires considerable human and financial resources and time. In the short and medium term, vaccination may help to prevent and control the spread of cholera outbreaks. Regardless of the intervention, further understanding of cholera biology and epidemiology is essential to identify populations and areas at increased risk and thus ensure the most efficient use of scarce resources for the prevention and control of cholera.

  14. Strengthening field-based training in low and middle-income countries to build public health capacity: Lessons from Australia's Master of Applied Epidemiology program

    PubMed Central

    Patel, Mahomed S; Phillips, Christine B

    2009-01-01

    Background The International Health Regulations (2005) and the emergence and global spread of infectious diseases have triggered a re-assessment of how rich countries should support capacity development for communicable disease control in low and medium income countries (LMIC). In LMIC, three types of public health training have been tried: the university-based model; streamed training for specialised workers; and field-based programs. The first has low rates of production and teaching may not always be based on the needs and priorities of the host country. The second model is efficient, but does not accord the workers sufficient status to enable them to impact on policy. The third has the most potential as a capacity development measure for LMIC, but in practice faces challenges which may limit its ability to promote capacity development. Discussion We describe Australia's first Master of Applied Epidemiology (MAE) model (established in 1991), which uses field-based training to strengthen the control of communicable diseases. A central attribute of this model is the way it partners and complements health department initiatives to enhance workforce skills, health system performance and the evidence-base for policies, programs and practice. Summary The MAE experience throws light on ways Australia could collaborate in regional capacity development initiatives. Key needs are a shared vision for a regional approach to integrate training with initiatives that strengthen service and research, and the pooling of human, financial and technical resources. We focus on communicable diseases, but our findings and recommendations are generalisable to other areas of public health. PMID:19358710

  15. Application of Pulsed-Field Gel Electrophoresis and Binary Typing as Tools in Veterinary Clinical Microbiology and Molecular Epidemiologic Analysis of Bovine and Human Staphylococcus aureus Isolates

    PubMed Central

    Zadoks, Ruth; van Leeuwen, Willem; Barkema, Herman; Sampimon, Otlis; Verbrugh, Henri; Schukken, Ynte Hein; van Belkum, Alex

    2000-01-01

    Thirty-eight bovine mammary Staphylococcus aureus isolates from diverse clinical, temporal, and geographical origins were genotyped by pulsed-field gel electrophoresis (PFGE) after SmaI digestion of prokaryotic DNA and by means of binary typing using 15 strain-specific DNA probes. Seven pulsed-field types and four subtypes were identified, as were 16 binary types. Concordant delineation of genetic relatedness was documented by both techniques, yet based on practical and epidemiological considerations, binary typing was the preferable method. Genotypes of bovine isolates were compared to 55 previously characterized human S. aureus isolates through cluster analysis of binary types. Genetic clusters containing strains of both human and bovine origin were found, but bacterial genotypes were predominantly associated with a single host species. Binary typing proved an excellent tool for comparison of S. aureus strains, including methicillin-resistant S. aureus, derived from different host species and from different databases. For 28 bovine S. aureus isolates, detailed clinical observations in vivo were compared to strain typing results in vitro. Associations were found between distinct genotypes and severity of disease, suggesting strain-specific bacterial virulence. Circumstantial evidence furthermore supports strain-specific routes of bacterial dissemination. We conclude that PFGE and binary typing can be successfully applied for genetic analysis of S. aureus isolates from bovine mammary secretions. Binary typing in particular is a robust and simple method and promises to become a powerful tool for strain characterization, for resolution of clonal relationships of bacteria within and between host species, and for identification of sources and transmission routes of bovine S. aureus. PMID:10790124

  16. Accuracy of industry and occupation on death certificates of electric utility workers: implications for epidemiologic studies of magnetic fields and cancer.

    PubMed

    Andrews, K W; Savitz, D A

    1999-12-01

    A substantial epidemiologic literature has relied on occupation and industry information from death certificates to make inferences about the association of electric and magnetic field exposure with cancer, but the validity of the occupational data on death certificates is questionable. We compared occupation and industry information from death certificates to company work histories for 793 electric utility workers who died from brain cancer (n=143), leukemia (n=156), lung cancer (n=246, randomly sampled), and non-cancer causes (n=248, randomly sampled). Nearly 75% of death certificates correctly indicated utility industry employment and of those, 48% matched the longest held occupation derived from company work histories. Hence, only 36% matched on both industry and occupation. We computed odds ratios relating occupations involving magnetic field exposure to brain cancer and leukemia both for the occupation listed on the death certificate and for the longest-held occupation based on company records in order to examine the impact of exposure misclassification based on reliance on the death certificate information. For brain cancer, the odds ratio was 1.2 based on death certificates and 1.7 based on company work history, suggesting some attenuation due to misclassification. For leukemia, death certificate information yielded an odds ratio of 0.9, whereas company work histories yielded an odds ratio of 1.3. Although work histories are limited to the period of employment in a specific company, these data suggest that there is substantial misclassification in use of death certificate information on industry and occupation of utility workers, as found in other industries. The limited quality of occupation and industry information on death certificates argues against relying on such information to evaluate modest associations with mortality.

  17. A little bit of Africa in Brazil: ethnobiology experiences in the field of Afro-Brazilian religions

    PubMed Central

    2014-01-01

    This essay, which is the fourth in the series “Recollections, Reflections, and Revelations: Ethnobiologists and Their First Time in the Field”, is a personal reflection by the researcher on his first field experience with ethnobiology of so called Afro-brazilian cults. The author recounts his feelings and concerns associated with initial fieldwork. PMID:24467714

  18. A diagnosis of sub-surface water table dynamics in low hydraulic conductivity soils in the sugar cane fields of Pongola, South Africa

    NASA Astrophysics Data System (ADS)

    Malota, Mphatso; Senzanje, Aidan

    2016-04-01

    Water and land are the two natural resources restraining crop production in South Africa. With the increasing demand for food, emphasis has shifted from the sole reliance on rain fed crop production, to irrigation. The deterioration in irrigation water quality from surface water sources is, however, posing a big challenge to the sustainability of irrigated crop production. This is because more water is required for leaching, resulting in shallow water tables in agricultural lands. The installation of well designed subsurface drainage systems alone is not enough; the provision of timely maintenance is also necessary. In this study, the extent and severity of problems as a consequence of shallow water tables and their possible causes were investigated at three sugarcane fields in Pongola, South Africa, having low hydraulic conductivity soils. Also investigated were soil salinity levels and the temporal variation in the salinity of the irrigation water. A water table map of a 32 ha sugarcane field was generated, using observed water table depth (WTD) data from 36 piezometers monitored from September 2011 to February 2012. Out of the total 32 ha under cultivation, 12% was found to be affected by shallow WTDs of less than the 1.0 m design WTD. The inability of natural drainage to cope with subsurface drainage needs and the poor maintenance of subsurface drainage systems contributed to the shallow water tables in the area. Furthermore, the currently adopted drainage design criteria also proved unsatisfactory with mean observed water table depth and drainage discharge (DD) of 20% and 50%, respectively, less than their respective design levels. The salinity of the irrigation water was, on average, 32% higher than threshold tolerance level of sugarcane. The root zone soil salinity levels at the three study sites were greater than the 1.7 dS m-1 threshold for sugar cane. The subsurface drainage design criteria adopted at the site needs to be revisited by ensuring that the

  19. Needed: optics light in Africa

    NASA Astrophysics Data System (ADS)

    Kingsley, Akanihu

    2005-10-01

    Though Africa is known and in many quarters still referred to as the dark continent, should she still be in that state in this day and time in which we live? Data now travels at the speed of light and information reaches every nook and cranny of the earth, and I ask, can some of this not be directed towards Africa? More attention needs to be focused on educating Africa in the fields of photonics and optics to illuminate her because if mother earth has got to progress, no part of her or her children can and should be left behind.

  20. Low geomagnetic field intensity in the Matuyama Chron: palaeomagnetic study of a lava sequence from Afar depression, East Africa

    NASA Astrophysics Data System (ADS)

    Ahn, Hyeon-Seon; Kidane, Tesfaye; Yamamoto, Yuhji; Otofuji, Yo-ichiro

    2016-01-01

    Palaeointensity variation is investigated for an inferred time period spanning from 2.34 to 1.96 Ma. Twenty-nine consecutive lava flows are sampled along cliffs 350 m high generated by normal faulting on the Dobi section of Afar depression, Ethiopia. Magnetostratigraphy and K-Ar measurements indicate a lava sequence of R-N-R-N geomagnetic field polarities in ascending order; the lower normal polarity is identified as the Réunion Subchron. Reliability of palaeomagnetic data is ascertained through careful thermal demagnetization and by the reversal test. The Tsunakawa-Shaw method yielded 70 successful palaeointensity results from 24 lava flows and gave 11 acceptable mean palaeointensities. Reliability in palaeointensity data is ascertained by the similar values obtained by the IZZI-Thellier method and thus 11 reliable mean values are obtained from our combined results. After the older reverse polarity with the field intensity of 19.6 ± 7.8 μT, an extremely low palaeointensity period with an average of 6.4 μT is shown to occur prior to the Réunion Subchron. During the Réunion Subchron, the dipole field strength is shown to have returned to an average of 19.5 μT, followed by second extreme low of 3.6 μT and rejuvenation with 17.1 ± 5.3 μT in the younger reverse polarity. This `W-shape' palaeointensity variation is characterized by occurrences of two extremely weak fields lower than 8 μT prior to and during the Réunion Subchron and a relatively weak time-averaged field of approximately 15 μT. This feature is also found in sedimentary cores from the Ontong Java Plateau and the north Atlantic, indicative of a possibly global geomagnetic field phenomenon rather than a local effect on Ethiopia. Furthermore, we estimate a weak virtual axial dipole moment of 3.66 (±1.85) × 1022 Am2 during early stage of the Matuyama Chron (inferred time period of 2.34-1.96 Ma).

  1. AIDS in South Africa.

    PubMed

    Ijsselmuiden, C; Evian, C; Matjilla, J; Steinberg, M; Schneider, H

    1993-01-01

    The National AIDS Convention in South Africa (NACOSA) in October 1992 was the first real attempt to address HIV/AIDS. In Soweto, government, the African National Congress, nongovernmental organizations, and organized industry and labor representatives worked for 2 days to develop a national plan of action, but it did not result in a united effort to fight AIDS. The highest HIV infection rates in South Africa are among the KwaZulu in Natal, yet the Inkatha Freedom Party did not attend NACOSA. This episode exemplifies the key obstacles for South Africa to prevent and control AIDS. Inequality of access to health care may explain why health workers did not diagnose the first AIDS case in blacks until 1985. Migrant labor, Bantu education, and uprooted communities affect the epidemiology of HIV infection. Further, political and social polarization between blacks and whites contributes to a mindset that AIDS is limited to the other race which only diminishes the personal and collective sense of susceptibility and the volition and aptitude to act. The Department of National Health and Population Development's voluntary register of anonymously reported cases of AIDS specifies 1517 cumulative AIDS cases (October 1992), but this number is low. Seroprevalence studies show between 400,000-450,000 HIV positive cases. Public hospitals cannot give AIDS patients AZT and DDI. Few communities provided community-based care. Not all hospitals honor confidentiality and patients' need for autonomy. Even though HIV testing is not mandatory, it is required sometimes, e.g., HIV testing of immigrants. AIDS Training, Information and Counselling Centers are in urban areas, but not in poor areas where the need is most acute. The government just recently developed in AIDS education package for schools, but too many people consider it improper, so it is not being used. The poor quality education provided blacks would make it useless anyhow. Lifting of the academic boycott will allow South African

  2. Exploring the Usefulness of MISR-HR Products to Estimate Maize Crop Extent and Using Field Evidence to Evaluate the Results in South Africa's Free State Province

    NASA Astrophysics Data System (ADS)

    Verstraete, M. M.; Knox, N. M.; Hunt, L. A.; Kleyn, L.

    2014-12-01

    The MISR instrument on NASA's Terra platform has been operating for almost 15 years. Standard products are generated at a spatial resolution of 1.1 km or coarser, but a recently developed method to re-analyze the Level-1B2 data allows the retrieval of biogeophysical products at the native spatial resolution of the instrument (275 m). This development opens new opportunities to better address issues such as the management of agricultural production and food security. South African maize production is of great economic and social importance, not only nationally, but on the global market too, being one of the top ten maize producing countries. Seasonal maize production statistics are currently based on a combination of field measurements and estimates derived from manually digitizing high resolution imagery from the SPOT satellite. The field measurements are collected using the Producer Independent Crop Estimate System (PICES) developed by Crop Estimates Committee of the Department of Agriculture, Forestry and Fisheries. There is a strong desire to improve the quality of these statistics, to generate those earlier, and to automate the process to encompass larger areas. This paper will explore the feasibility of using the MISR-HR spectral and directional products, combined with the finer spatial resolution and the relatively frequent coverage afforded by that instrument, to address these needs. The study area is based in the Free State, South Africa, one of the primary maize growing areas in the country, and took place during the 2012-2013 summer growing season. The significance of the outcomes will be evaluated in the context of the 14+ years of available MISR data.

  3. Monitoring Dry Season Persistence of Anopheles gambiae s.l. Populations in a Contained Semi-Field System in Southwestern Burkina Faso, West Africa.

    PubMed

    Mamai, W; Simard, F; Couret, D; Ouedraogo, G A; Renault, D; Dabiré, K R; Mouline, K

    2016-01-01

    To gain insight into the dry season survival strategies of Anopheles gambiae s.l., a new contained semi-field system was developed and used for the first time in Burkina Faso, West Africa. The system consisted of a screened greenhouse within which the local environment was reproduced, including all ecological requirements for mosquito development cycle completion. The system was seeded with the progenies of female Anopheles gambiae, Anopheles coluzzii, and Anopheles arabiensis collected in the vicinity of the greenhouse during the rainy season. After successful establishment in the semi-field system, mosquito populations were monitored over a 1-yr period by regular surveys of larval and adult specimens. We provided evidence for the persistence of adult mosquitoes throughout the dry season, in the absence of any suitable larval development site. During the hot and dry periods, adult insects were observed in artificial shelters (clay pots, building blocks, and dark corners). The mosquito population rapidly built up with the return of the rainy season in the area, when artificial breeding sites were refilled in the enclosure. However, only An. coluzzii and, later, An. arabiensis were detected in the subsequent rainy season, whereas no An. gambiae specimen was found. Our findings suggest that An. coluzzii and An. arabiensis may be able to aestivate throughout the dry season in Southwestern Burkina Faso, whereas An. gambiae might adopt a different dry-season survival strategy, such as long-distance re-colonization from distant locations. These results may have important implications for malaria control through targeted vector control interventions. PMID:26576935

  4. Mapping the state of the field of social psychology in Africa and patterns of collaboration between African and international social psychologists.

    PubMed

    Quayle, Michael; Greer, Megan

    2014-12-01

    Patterns of collaboration in social psychology from 2000 to 2010 were mapped to analyse the position of African authors in the international co-authorship network using bibliographic records from the Thomson Reuters Web of Knowledge. There are very few social psychologists working in Africa, with the majority of these located in South Africa. Indeed, some small European countries boast more social psychologists than the entire continent of Africa. African authors published less than their non-African collaborators, but had comparable status on joint publications. Co-authorship relationships between African researchers from different African countries were generally mediated by partners from other continents, and direct collaboration between non-compatriot African authors was very rare. The small size, and extremely sparse connection of the African co-authorship network, is likely to be an obstacle both in the development of social psychology as a universally relevant discipline and in the penetration of social psychological knowledge in Africa.

  5. Setting Research Priorities for HIV/AIDS-related research in a post-graduate training programme: lessons learnt from the Nigeria Field Epidemiology and Laboratory Training Programme scientific workshop

    PubMed Central

    Poggensee, Gabriele; Waziri, Ndadilnasiya Endie; Bashorun, Adebobola; Nguku, Patrick Mboya; Fawole, Olufunmilayo Ibitola; Sabitu, Kabir

    2014-01-01

    In Nigeria the current prevalence of HIV is 4.1% with over 3.5 million infected and estimated 1.5 million in need of anti-retroviral treatment. Epidemiological and implementation studies are necessary for monitoring and evaluation of interventions. To define research areas which can be addressed by participants of the Nigeria Field Epidemiology and Training Programme (NFELTP) a workshop was held in April 2013 in Abuja, Nigeria. Priority research areas were identified using criteria lists for ranking of the relevance of research questions. Based on a research matrix, NFELTP residents developed the aims and objectives, study design for HIV-related research proposals. This workshop was the first workshop held by the NFELTP to establish an inventory of research questions which can be addressed by the residents within their training period. This inventory will help to increase HIV/AIDS-related activities of NFELTP which are in accordance with research needs in Nigeria and PEPFAR objectives. PMID:25426209

  6. Electromagnetic fields and health effects--epidemiologic studies of cancer, diseases of the central nervous system and arrhythmia-related heart disease.

    PubMed

    Johansen, Christoffer

    2004-01-01

    This epidemiologic investigation comprised separate studies of the risk of cancer, cause-specific mortality rates, risks for neurodegenerative diseases, and the risk of arrhythmia-related heart disease among employees exposed to extremely low-frequency (50-Hz) electromagnetic fields (EMF) in the Danish utility industry. All the employees in this industry were followed-up in several registers. The risk of disease was analyzed in relation to occupational exposure to EMF, latency, and duration of employment. A specific job-exposure matrix was developed and validated by comparison with direct measurements of EMF during a workday. Linkage with the Danish Cancer Register did not identify increased risks for the cancers suggested a priori to be associated with exposure to EMF, including leukemia, brain tumors, and breast cancer. Significantly increased risks for lung cancer and mesothelioma were identified for workers highly exposed to asbestos. Linkage with the National Mortality Register revealed a significantly increased overall mortality rate from amyotrophic lateral sclerosis (ALS), with an increasing trend with duration of employment and EMF exposure. In addition, a significantly increased mortality rate from electric accidents was observed. It was hypothesized that the observation of increased mortality from ALS was associated with exposure to EMF or electric shocks. No increased mortality rate from cardiovascular or cerebrovascular disease was observed. Linkage with the National Hospital Register also revealed an increased risk of ALS and, thereby confirmed the finding of an increased mortality rate for this disease in the previous study. Linkage of the cohort with the Multiple Sclerosis Register revealed an increased risk of multiple sclerosis, which was not, however, significant. Linkage with the Pacemaker Register showed no increased risk of severe arrhythmia-related heart disease. The second part of the study included the establishment of a large, nationwide

  7. West Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    With its vast expanses of sand, framed by mountain ranges and exposed rock, northwestern Africa makes a pretty picture when viewed from above. This image was acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. The Canary Islands can be seen on the left side of the image just off Africa's Atlantic shore. The light brown expanse running through the northern two thirds of the image is the Sahara Desert. The desert runs up against the dark brown Haut Atlas mountain range of Morocco in the northwest, the Atlantic Ocean to the west and the semi-arid (light brown pixels) Sahelian region in the South. The Sahara, however, isn't staying put. Since the 1960s, the desert has been expanding into the Sahelian region at a rate of up to 6 kilometers per year. In the 1980s this desert expansion, combined with over cultivation of the Sahel, caused a major famine across west Africa. Over the summer months, strong winds pick up sands from the Sahara and blow them across the Atlantic as far west as North America, causing air pollution in Miami and damaging coral reefs in the Bahamas and the Florida Keys. The white outlines on the map represent country borders. Starting at the top-most portion of the map and working clockwise, the countries shown are Morocco, Western Sahara, Mauritania, Senegal, Mali, Burkina Fasso, Nigeria, Mali (again), and Algeria. Image by Reto Stockli, Robert Simmon, and Brian Montgomery, NASA Earth Observatory, based on data from MODIS

  8. Performance Evaluation of the Becton Dickinson FACSPresto™ Near-Patient CD4 Instrument in a Laboratory and Typical Field Clinic Setting in South Africa

    PubMed Central

    Coetzee, Lindi-Marie; Moodley, Keshendree; Glencross, Deborah Kim

    2016-01-01

    Background The BD-FACSPresto™ CD4 is a new, point-of-care (POC) instrument utilising finger-stick capillary blood sampling. This study evaluated its performance against predicate CD4 testing in South Africa. Methods Phase-I testing: HIV+ patient samples (n = 214) were analysed on the Presto™ under ideal laboratory conditions using venous blood. During Phase-II, 135 patients were capillary-bled for CD4 testing on FACSPresto™, performed according to manufacturer instruction. Comparative statistical analyses against predicate PLG/CD4 method and industry standards were done using GraphPad Prism 6. It included Bland-Altman with 95% limits of agreement (LOA) and percentage similarity with coefficient of variation (%CV) analyses for absolute CD4 count (cells/μl) and CD4 percentage of lymphocytes (CD4%). Results In Phase-I, 179/217 samples yielded reportable results with Presto™ using venous blood filled cartridges. Compared to predicate, a mean bias of 40.4±45.8 (LOA of -49.2 to 130.2) and %similarity (%CV) of 106.1%±7.75 (7.3%) was noted for CD4 absolute counts. In Phase-2 field study, 118/135 capillary-bled Presto™ samples resulted CD4 parameters. Compared to predicate, a mean bias of 50.2±92.8 (LOA of -131.7 to 232) with %similarity (%CV) 105%±10.8 (10.3%), and 2.87±2.7 (LOA of -8.2 to 2.5) with similarity of 94.7±6.5% (6.83%) noted for absolute CD4 and CD4% respectively. No significant clinical differences were indicated for either parameter using two sampling methods. Conclusion The Presto™ produced remarkable precision to predicate methods, irrespective of venous or capillary blood sampling. A consistent, clinically insignificant over-estimation (5–7%) of counts against PLG/CD4 and equivalency to FACSCount™ was noted. Further field studies are awaited to confirm longer-term use. PMID:27224025

  9. Plasmodium vivax Transmission in Africa

    PubMed Central

    Howes, Rosalind E.; Reiner Jr., Robert C.; Battle, Katherine E.; Longbottom, Joshua; Mappin, Bonnie; Ordanovich, Dariya; Tatem, Andrew J.; Drakeley, Chris; Gething, Peter W.; Zimmerman, Peter A.; Smith, David L.; Hay, Simon I.

    2015-01-01

    Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf). Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv) transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health significance of Pv, as well

  10. Plasmodium vivax Transmission in Africa.

    PubMed

    Howes, Rosalind E; Reiner, Robert C; Battle, Katherine E; Longbottom, Joshua; Mappin, Bonnie; Ordanovich, Dariya; Tatem, Andrew J; Drakeley, Chris; Gething, Peter W; Zimmerman, Peter A; Smith, David L; Hay, Simon I

    2015-11-01

    Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf). Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv) transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health significance of Pv, as well

  11. Astrophysics in Southern Africa

    NASA Astrophysics Data System (ADS)

    Whitelock, Patricia

    2008-03-01

    The government of South Africa has identified astronomy as a field in which their country has a strategic advantage and is consequently investing very significantly in astronomical infrastructure. South Africa now operates a 10-m class optical telescope, the Southern African Large Telescope (SALT), and is one of two countries short listed to host the Square Kilometre Array (SKA), an ambitious international project to construct a radio telescope with a sensitivity one hundred times that of any existing telescope. The challenge now is to produce an indigenous community of users for these facilities, particularly from among the black population which was severely disadvantaged under the apartheid regime. In this paper I briefly describe the observing facilities in Southern Africa before going on to discuss the various collaborations that are allowing us to use astronomy as a tool for development, and at the same time to train a new generation of astronomers who will be well grounded in the science and linked to their colleagues internationally.

  12. Q&A: Muin Khoury on cancer epidemiology.

    PubMed

    Khoury, Muin J; Rose, Suzanne

    2014-02-01

    Muin J. Khoury, MD, PhD, director of the Centers for Disease Control and Prevention's Office of Public Health Genomics and head of the National Cancer Institute's Epidemiology and Genomics Research Program in the Division of Cancer Control and Population Sciences, talks about challenges and opportunities in cancer epidemiology research and efforts in the epidemiology community to transform the field.

  13. Evaluating the usefulness of spa typing, in comparison with pulsed-field gel electrophoresis, for epidemiological typing of methicillin-resistant Staphylococcus aureus in a low-prevalence region in Sweden 2000-2004.

    PubMed

    Petersson, A C; Olsson-Liljequist, B; Miörner, H; Haeggman, S

    2010-05-01

    The usefulness of spa typing was evaluated in relation to pulsed-field gel electrophoresis (PFGE), as a tool for epidemiological typing of methicillin-resistant Staphylococcus aureus (MRSA) in a low-prevalence region in southern Sweden. Bacterial isolates from 216 MRSA cases, newly identified in 2000-2004, were studied. The isolates were obtained from infected patients (31%), and from colonized individuals found by screening (69%). In total, 49 spa types and 73 PFGE patterns were identified. The discriminatory power of spa typing was lower (94.9 +/- 1.8%) than that of PFGE (97.3 +/- 1.2%). For two spa types (t002 and t008) the Panton-Valentine leukocidin results added useful discriminatory information. The most common spa types were t044 (n = 31; four PFGE patterns), t002 (n = 24; 10 PFGE patterns), t067 (n = 12; four PFGE patterns), t050 (n = 12; one PFGE pattern), and t324 (n = 11; one PFGE pattern). Epidemiological investigations identified 91 single cases and 39 transmission chains, each involving two to 13 cases. All the transmission chains were held together both by spa and PFGE typing. Among the 91 single-case isolates, 33 spa types and 50 PFGE patterns were unique (matchless) at the time of identification. The low prevalence of MRSA, the low number of outbreaks, and the wide spectrum of strains due to frequent acquisitions abroad (49% of the cases), makes spa typing a useful complement to epidemiological investigations in our setting. However, we still recommend the continued use of PFGE for further discrimination of isolates with identical spa types when epidemiological data can not exclude possible transmission.

  14. Near-Field High-Resolution Seismic, Strain and Displacement Measurements for Earthquake Source Studies in Deep Mines in South Africa

    NASA Astrophysics Data System (ADS)

    Johnston, M. J.; Reches, Z.; van Aswegan, G.; McGarr, A.; Lockner, D.; Sellers, E.; Ben Zion, Y.; Williams, C.

    2004-12-01

    Unique access to information on the physics of the earthquake source (earthquake nucleation, fault rupture, heat generation, stress state, seismic wave propagation, fault displacement, material properties and particularly changes in some of these parameters prior to rupture) exists in the near-field of mining-induced earthquakes in deep gold mines in South Africa. The new NSF funded Natural Earthquake Laboratory in South African Mines (NELSAM) will provide seismic velocity/acceleration, ground strain, temperature, fault displacement, acoustic emission (AE), and perhaps self-potential (SP) data in small 3-D arrays across and within active faults in two different mines. 3-component accelerometers to be installed in or near the faults have a range from micro g to 0.5 g in the band 0.05 - 500 Hz. Fault displacement meters (creepmeters) to be installed at low angles across faults within boreholes have a range of microns to 0.2 m and cover the frequency range from DC to 100 Hz. Successful measurement of total displacement will depend on the creepmeter reference length surviving the fault rupture. Temperature will be measured to millidegrees C at points within, and at increasing distances from fault zones, to capture the heat generated by future and past earthquakes. Strain transients will be measured with 3-component near-fault borehole strainmeters with capacitance displacement transducers providing a resolution < 10E-9. 3-component seismic velocity transducers will be installed together with each accelerometer and supplement the current mine seismic network. AE and SP will be measured within boreholes crossing faults if recording capability is sufficient. All data will be digitally sampled and transmitted to the surface in real-time for analysis to focus on unraveling the physics of the nucleation process, non-linear deformation prior to rupture, propagating aseismic slip, and variation in the material properties of near-fault materials (e.g. state/rate dependent

  15. Fires in Central Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Hundreds of fires are set every year during the dry season in Central Africa. This true color image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows dozens of smoke plumes in the Democratic Republic of the Congo on June 29, 2000. Residents burn away scrub and brush annually in the woody savanna to clear land for farming and grazing. For more information, visit the SeaWiFS Home Page, Global Fire Monitoring Fact Sheet, and 4km2 Fire Data Image Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  16. AIDS in Africa.

    PubMed

    Wilson, D; Armstrong, M; Lavelle, S

    1991-01-01

    Works on epidemiological, and social and behavioral science aspects of AIDS prevention and support in Africa are reviewed from the 7th Conference on AIDS. Participants were especially concerned with why AIDS spreads at disparate rates in different countries and regions of the world. Research on the casual factors of the spread of HIV generally focused upon patterns of sex behavior, the presence of other STDs, and the effect of circumcision. The roles of certain vaginal tightening agents used by Zairian prostitutes, vaginal bruising and bleeding, sex during menses, and oral contraception were also considered. Further, participants explored the possibility of a more coordinated, integrated approach to research and intervention development between the medical and social disciplines, and expressed the overall need for concurrent mass education interventions. In the face of ever increasing rates of HIV infection, including vertical transmission, making condoms ubiquitous, affordable, and highly publicized should garner higher general acceptance and use rates in these populations. Papers and models on the micro- and macro-socioeconomic impact of AIDS were finally discussed, followed by recommendations for a complete reassessment and reworking of policy for AIDS prevention. AIDS activities should, in fact, be integrated into the daily fabric of society, with prevention measures considered an ultimate necessity for social survival.

  17. International Lymphoma Epidemiology Consortium

    Cancer.gov

    The InterLymph Consortium, or formally the International Consortium of Investigators Working on Non-Hodgkin's Lymphoma Epidemiologic Studies, is an open scientific forum for epidemiologic research in non-Hodgkin's lymphoma.

  18. Complete Genome Sequences of Five Bluetongue Virus (BTV) Vaccine Strains from a Commercial Live Attenuated Vaccine, a BTV-4 Field Strain from South Africa, and a Reassortant Strain Isolated from Experimentally Vaccinated Cattle

    PubMed Central

    Coetzee, Peter; le Grange, Misha; Venter, Estelle H.

    2016-01-01

    This is a report of the complete genome sequences of plaque-selected isolates of each of the five virus strains included in a South African commercial trivalent bluetongue virus (BTV) attenuated live virus vaccine, a BTV-4 field strain isolated from Rustenburg, South Africa, in 2011, and a bluetongue reassortant (bluetongue virus 4 strain 4/O. aries-tc/ZAF/11/OBP-115) isolated from experimentally vaccinated cattle. Full-genome sequencing and phylogenetic analyses show that the bluetongue virus 9 strain 9/B. taurus-tc/ZAF/15/Onderstepoort_B02b is a reassortant virus containing segments from both BTV-9 and BTV-8. PMID:27340051

  19. Cancer Epidemiology Matters Blog

    Cancer.gov

    The Cancer Epidemiology Matters blog helps foster a dialogue between the National Cancer Institute's (NCI) Epidemiology and Genomics Research Program (EGRP), extramural researchers, and other individuals, such as clinicians, community partners, and advocates, who are interested in cancer epidemiology and genomics.

  20. Systematic review of birth cohort studies in Africa

    PubMed Central

    Campbell, Alasdair; Rudan, Igor

    2011-01-01

    Aim In sub-Saharan Africa, unacceptably high rates of mortality amongst women and children continue to persist. The emergence of research employing new genomic technologies is advancing knowledge on cause of disease. This review aims to identify birth cohort studies conducted in sub-Saharan Africa and to consider their suitability as a platform to support genetic epidemiological studies. Methods A systematic literature review was conducted to identify birth cohort studies in sub-Saharan Africa across the following databases: MEDLINE, EMBASE, AFRO and OpenSIGLE. A total of 8110 papers were retrieved. Application of inclusion/exclusion criteria retained only 189 papers, of which 71 met minimum quality criteria and were retained for full text analysis. Results The search revealed 28 birth cohorts: 14 of which collected biological data, 10 collected blood samples and only one study collected DNA for storage. These studies face many methodological challenges: notably, high rates of attrition and lack of funding for several rounds of study follow up. Population-based ‘biobanks’ have emerged as a major approach to harness genomic technologies in health research and yet the sub-Saharan African region still awaits large scale birth cohort biobanks collecting DNA and associated health and lifestyle data. Conclusion Investment in this field, together with related endeavours to foster and develop research capacity for these studies, may lead to an improved understanding of the determinants of intrauterine growth and development, birth outcomes such as prematurity and low birth weight, the links between maternal and infant health, survival of infectious diseases in the first years of life, and response to vaccines and antibiotic treatment. PMID:23198102

  1. Epidemiology of yaws: an update

    PubMed Central

    Kazadi, Walter M; Asiedu, Kingsley B; Agana, Nsiire; Mitjà, Oriol

    2014-01-01

    Yaws, a neglected tropical disease, is targeted for eradication by 2020 through large-scale mass-treatment programs of endemic communities. A key determinant for the success of the eradication campaign is good understanding of the disease epidemiology. We did a review of historical trends and new information from endemic countries, with the aim of assessing the state of knowledge on yaws disease burden. Transmission of yaws is now present in Africa, Asia, and the South Pacific. At least 12 countries are known to harbor yaws cases and 21 to 42 million people live in endemic areas. Between 2008 and 2012 more than 300,000 new cases were reported to the World Health Organization. Yaws presented high geographical variation within a country or region, high seasonality for incidence of active disease, and evidence that low standards of hygiene predispose to suffering of the disease. Key data issues include low levels of reporting, potential misdiagnosis, and scarce documentation on prevalence of asymptomatic infections. Currently available data most likely underestimates the magnitude of the disease burden. More effort is needed in order to refine accuracy of data currently being reported. A better characterization of the epidemiology of yaws globally is likely to positively impact on planning and implementation of yaws eradication. PMID:24729728

  2. [Epidemiological stratification of malaria in Madagascar].

    PubMed

    Mouchet, J; Blanchy, S; Rakotonjanabelo, A; Ranaivoson, G; Rajaonarivelo, E; Laventure, S; Rossella, M; Aknouche, F

    1993-01-01

    Madagascar is considered as a sub-region of the Afrotropical geographical Region in spite of the high endemicity of 95% of the invertebrates. Nevertheless the three malaria vectors An. gambiae s.s., An. arabiensis and An. funestus are quite similar to those of the continental Africa. This support the hypothesis of their recent introduction. Plasmodium falciparum is the dominant parasite but the prevalence of P. vivax is not negligible. It is linked to the Asian component of the human population. P. malariae and P. ovale are of minor importance. The main epidemiological "facies" of Africa are found in Madagascar. The equatorial facies on the East Coast is characterized by a high transmission all year long. In the tropical facies on the West Coast transmission is seasonal (7 months at least). In both areas, malaria is stable and the inhabitants acquire a high immunity before the age of ten; most of the severe cases touch children below 10. The three vectors can be found but An. gambiae s.s. is dominant. In the exophilic southern facies the transmission is seasonal (two to four months). The only vector is An. arabiensis. Malaria is unstable and severe epidemics occur during the years of high rainfall. All age groups are vulnerable because the population is not immune in the Plateaux facies above 1,000 m., malaria is unstable. Severe epidemics occurred in 1987-1988. The vectors are An. Arabiensis and An. funestus. The occurrence of P. falciparum on the Plateaux seems linked to the development of irrigation of rice farming in the XIXth century. Most of the anopheles breeding places on the Plateaux are dependent on rice cultivation. Urban development has brought the inhabitants of the suburbs in close contact with rice fields. Despite the high number of anopheline bites the number of malaria cases remains by far lower than in the neighbouring rural areas. Regional migrations inside the island bring non-immune populations, from the south and the plateaux, in highly

  3. Cultural Conundrums: The Ethics of Epidemiology and the Problems of Population in Implementing Pre-Exposure Prophylaxis

    PubMed Central

    2013-01-01

    The impending implementation of pre-exposure prophylaxis (PrEP) has prompted complicated bioethical and public health ethics concerns regarding the moral distribution of antiretroviral medications (ARVs) to ostensibly healthy populations as a form of HIV prevention when millions of HIV-positive people still lack access to ARVs globally. This manuscript argues that these questions are, in part, concerns over the ethics of epidemiological science and knowledge production practices. Questions of distribution, and their attendant cost-benefit calculations, will rely on a number of presupposed, and therefore, normatively cultural assumptions within the science of epidemiology specifically regarding the ability of epidemiological surveillance to produce accurate maps of HIV throughout national populations. Specifically, ethical questions around PrEP will focus on who should receive ARVs given the fact that global demand will far exceed supply. Given that sexual transmission is one of the main modes of HIV transmission, these questions of “who” are inextricably linked to knowledge about sex, gender and sexuality. As a result, the ethics of epidemiology, and how the epidemiology of HIV in particular conceives, classifies and constructs sexual populations will become a critical point of reflection and contestation for bioethicists, health activists, physicians, nurses, and researchers in the medical humanities and biomedicine. This paper examines how cultural conundrums within the fields of bio- and public health ethics are directly implicated within the ethics of PrEP, by analyzing the problems of population inaugurated by the construction of the men who have sex with men (MSM) epidemiological category in the specific national context of South Africa. PMID:24373050

  4. The Checkered History of American Psychiatric Epidemiology

    PubMed Central

    Horwitz, Allan V; Grob, Gerald N

    2011-01-01

    Context American psychiatry has been fascinated with statistics ever since the specialty was created in the early nineteenth century. Initially, psychiatrists hoped that statistics would reveal the benefits of institutional care. Nevertheless, their fascination with statistics was far removed from the growing importance of epidemiology generally. The impetus to create an epidemiology of mental disorders came from the emerging social sciences, whose members were concerned with developing a scientific understanding of individual and social behavior and applying it to a series of pressing social problems. Beginning in the 1920s, the interest of psychiatric epidemiologists shifted to the ways that social environments contributed to the development of mental disorders. This emphasis dramatically changed after 1980 when the policy focus of psychiatric epidemiology became the early identification and prevention of mental illness in individuals. Methods This article reviews the major developments in psychiatric epidemiology over the past century and a half. Findings The lack of an adequate classification system for mental illness has precluded the field of psychiatric epidemiology from providing causal understandings that could contribute to more adequate policies to remediate psychiatric disorders. Because of this gap, the policy influence of psychiatric epidemiology has stemmed more from institutional and ideological concerns than from knowledge about the causes of mental disorders. Conclusion Most of the problems that have bedeviled psychiatric epidemiology since its inception remain unresolved. In particular, until epidemiologists develop adequate methods to measure mental illnesses in community populations, the policy contributions of this field will not be fully realized. PMID:22188350

  5. The importance of sensitive detection of malaria parasites in the human and insect hosts in epidemiological studies, as shown by the analysis of field samples from Guinea Bissau.

    PubMed

    Snounou, G; Pinheiro, L; Gonçalves, A; Fonseca, L; Dias, F; Brown, K N; do Rosario, V E

    1993-01-01

    A method based on the polymerase chain reaction (PCR) for highly sensitive detection and identification of human malaria parasites was applied to blood and mosquito samples obtained from a village in Guinea Bissau. The prevalence of parasites in the human population was shown to be greatly underestimated by microscopical examination. In particular, a high incidence of Plasmodium malariae and P. ovale parasites was revealed only by the PCR assay. Preliminary evidence was obtained to show that the distribution of P. malariae infections within the village was non-random. This was supported by analysis of the parasite species infecting the mosquito vector. The implication of these results for the design and interpretation of epidemiological surveys is discussed.

  6. The effect of malaria control on Plasmodium falciparum in Africa between 2000 and 2015.

    PubMed

    Bhatt, S; Weiss, D J; Cameron, E; Bisanzio, D; Mappin, B; Dalrymple, U; Battle, K E; Moyes, C L; Henry, A; Eckhoff, P A; Wenger, E A; Briët, O; Penny, M A; Smith, T A; Bennett, A; Yukich, J; Eisele, T P; Griffin, J T; Fergus, C A; Lynch, M; Lindgren, F; Cohen, J M; Murray, C L J; Smith, D L; Hay, S I; Cibulskis, R E; Gething, P W

    2015-10-01

    Since the year 2000, a concerted campaign against malaria has led to unprecedented levels of intervention coverage across sub-Saharan Africa. Understanding the effect of this control effort is vital to inform future control planning. However, the effect of malaria interventions across the varied epidemiological settings of Africa remains poorly understood owing to the absence of reliable surveillance data and the simplistic approaches underlying current disease estimates. Here we link a large database of malaria field surveys with detailed reconstructions of changing intervention coverage to directly evaluate trends from 2000 to 2015, and quantify the attributable effect of malaria disease control efforts. We found that Plasmodium falciparum infection prevalence in endemic Africa halved and the incidence of clinical disease fell by 40% between 2000 and 2015. We estimate that interventions have averted 663 (542-753 credible interval) million clinical cases since 2000. Insecticide-treated nets, the most widespread intervention, were by far the largest contributor (68% of cases averted). Although still below target levels, current malaria interventions have substantially reduced malaria disease incidence across the continent. Increasing access to these interventions, and maintaining their effectiveness in the face of insecticide and drug resistance, should form a cornerstone of post-2015 control strategies.

  7. Prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae isolated from blood cultures in Africa.

    PubMed

    Sangare, S A; Maiga, A I; Guindo, I; Maiga, A; Camara, N; Savadogo, S; Diallo, S; Bougoudogo, F; Armand-Lefevre, L; Andremont, A; Maiga, I I

    2015-09-01

    Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have been isolated from many regions of the world. Epidemiological studies are being conducted in Europe, North America, and Asia. No study has however been conducted in Africa to determine the prevalence and distribution of ESBLs on the continent. This literature review aimed at describing the prevalence of ESBL-producing Enterobacteriaceae isolated from blood cultures, as well as the ESBL genes involved at the international level. Our focus was mainly on Africa. We conducted a literature review on PubMed. Articles related to our study field and published between 1996 and 2014 were reviewed and entirely read for most of them, while we only focused on the abstracts of some other articles. Relevant articles to our study were then carefully reviewed and included in the review. The prevalence of ESBL-producing Enterobacteriaceae differs from one country to another. The results of our literature review however indicate that class A ESBLs prevail over the other types. We took into consideration articles focusing on various types of samples to assess the prevalence of ESBL-producing Enterobacteriaceae, but information on isolates from blood cultures is limited. The worldwide prevalence of ESBL-producing Enterobacteriaceae has increased over time. Evidence of ESBL-producing Enterobacteriaceae can be found in all regions of the world. Studies conducted in Africa mainly focused on the Northern and Eastern parts of the continent, while only rare studies were carried out in the rest of the continent. PMID:26433872

  8. [The francophone Africa blood transfusion research network: a five-year report].

    PubMed

    Tagny, Claude Tayou; Murphy, Edward L; Lefrère, Jean-Jacques

    2014-03-01

    There has been little blood safety research in sub-Saharan Africa, often consisting of local efforts whose findings had limited impact The "Francophone Africa Transfusion Research Network" was created in May 2007 with the objective of developing common evidence-based blood safety policies that may be adapted to each country's situation. The Group's activities to date have focused mainly on obtaining epidemiological and laboratory data on blood transfusion and on suggesting blood safety strategies, particularly in the field of TTIs. To carry out such research activities, the group works closely with the National Blood Transfusion Services (NBTS), the Regional Blood Transfusion Services (RBTS), the hospital blood banks (HBB) and collection stations. For the first 5years, four research priorities were identified: (i) descriptive studies of the characteristics of francophone African blood donors and blood centers; (ii) estimation of the residual risk of transfusion-transmitted major viral infections; (iii) an analysis of blood donor deferral strategies; and (iv) a description of TTI screening strategies and an external quality assurance system (EQAS) project. During this period, seven projects have been implemented at the national level and published and five multicenter studies were conducted and published. The present review reports the main observations and recommendations from those studies that could improve blood safety statute in Africa.

  9. The effect of malaria control on Plasmodium falciparum in Africa between 2000 and 2015.

    PubMed

    Bhatt, S; Weiss, D J; Cameron, E; Bisanzio, D; Mappin, B; Dalrymple, U; Battle, K E; Moyes, C L; Henry, A; Eckhoff, P A; Wenger, E A; Briët, O; Penny, M A; Smith, T A; Bennett, A; Yukich, J; Eisele, T P; Griffin, J T; Fergus, C A; Lynch, M; Lindgren, F; Cohen, J M; Murray, C L J; Smith, D L; Hay, S I; Cibulskis, R E; Gething, P W

    2015-10-01

    Since the year 2000, a concerted campaign against malaria has led to unprecedented levels of intervention coverage across sub-Saharan Africa. Understanding the effect of this control effort is vital to inform future control planning. However, the effect of malaria interventions across the varied epidemiological settings of Africa remains poorly understood owing to the absence of reliable surveillance data and the simplistic approaches underlying current disease estimates. Here we link a large database of malaria field surveys with detailed reconstructions of changing intervention coverage to directly evaluate trends from 2000 to 2015, and quantify the attributable effect of malaria disease control efforts. We found that Plasmodium falciparum infection prevalence in endemic Africa halved and the incidence of clinical disease fell by 40% between 2000 and 2015. We estimate that interventions have averted 663 (542-753 credible interval) million clinical cases since 2000. Insecticide-treated nets, the most widespread intervention, were by far the largest contributor (68% of cases averted). Although still below target levels, current malaria interventions have substantially reduced malaria disease incidence across the continent. Increasing access to these interventions, and maintaining their effectiveness in the face of insecticide and drug resistance, should form a cornerstone of post-2015 control strategies. PMID:26375008

  10. Cassava virus diseases: biology, epidemiology, and management.

    PubMed

    Legg, James P; Lava Kumar, P; Makeshkumar, T; Tripathi, Leena; Ferguson, Morag; Kanju, Edward; Ntawuruhunga, Pheneas; Cuellar, Wilmer

    2015-01-01

    Cassava (Manihot esculenta Crantz.) is the most important vegetatively propagated food staple in Africa and a prominent industrial crop in Latin America and Asia. Its vegetative propagation through stem cuttings has many advantages, but deleteriously it means that pathogens are passed from one generation to the next and can easily accumulate, threatening cassava production. Cassava-growing continents are characterized by specific suites of viruses that affect cassava and pose particular threats. Of major concern, causing large and increasing economic impact in Africa and Asia are the cassava mosaic geminiviruses that cause cassava mosaic disease in Africa and Asia and cassava brown streak viruses causing cassava brown streak disease in Africa. Latin America, the center of origin and domestication of the crop, hosts a diverse set of virus species, of which the most economically important give rise to cassava frog skin disease syndrome. Here, we review current knowledge on the biology, epidemiology, and control of the most economically important groups of viruses in relation to both farming and cultural practices. Components of virus control strategies examined include: diagnostics and surveillance, prevention and control of infection using phytosanitation, and control of disease through the breeding and promotion of varieties that inhibit virus replication and/or movement. We highlight areas that need further research attention and conclude by examining the likely future global outlook for virus disease management in cassava.

  11. Africa: Prosperous times

    SciTech Connect

    1996-08-01

    Political instability and corruption is the rule, rather than the exception, in Africa`s main producing regions, but exploration and production prospects there are bright and attractive to foreign operators. The paper discusses exploration, drilling, resource development, and production in Nigeria, Libya, Algeria, Egypt, Angola, Congo, Gabon, and Tunisia. The other countries of Africa are briefly mentioned, i.e., Cameroon, Cote D`Ivoire, South Africa, Sudan, Namibia, Equatorial Guinea, Eritrea, Zaire, Mozambique, Ghana, Niger, and Seychelles.

  12. Africa's Geomosaic under Stress.

    ERIC Educational Resources Information Center

    de Blij, H. J.

    1991-01-01

    Traces the transformation of Subsaharan Africa during the last 35 years. Contends that the domino effect hastened decolonization and increased polarization within South Africa. Argues that modernization is taking place only in South Africa's core and that the geopolitical framework appears stable but may collapse from within. (NL)

  13. Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

    PubMed

    Trinquart, Ludovic; Galea, Sandro

    2015-07-15

    An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field.

  14. Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

    PubMed

    Trinquart, Ludovic; Galea, Sandro

    2015-07-15

    An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field. PMID:25977517

  15. [Epidemiology of Kawasaki disease].

    PubMed

    Nakamura, Yosikazu

    2014-09-01

    Epidemiologic features of Kawasaki disease, in particular in Japan, were summarized. There were three aspects of the epidemiology: (1) frequency(descriptive epidemiology), (2) risk factors(e.g. case-control studies), and (3) natural history(follow-up studies). The nationwide surveys, which was established in 1970, revealed the epidemiologic features of the disease. The number of patients and incidence rate have elevated since mid-1990s. Descriptive features indicates the association between disease onset and both infection and the hosts' factors. A follow-up study over 20 years has been conducted, but it should be continued till all the participants pass away.

  16. South Africa: a toxicologist's goldmine.

    PubMed

    Stewart, Michael J

    2002-02-01

    The emerging nation of South Africa, in common with some other countries, notably Eastern Europe, is heir to decades of neglect with regards to the exposure of the majority of its population to toxic materials. In this short review, the major toxic health hazards are described. For most of these risks there are now programs in place to improve the situation, but co-ordination and financial constraints, along with the fact that the majority of the population neither live, nor work, in a controlled environment, mean that much remains to be done. The recent formation of a South African Toxicology society, which strives to bring together environmental, industrial, forensic and clinical toxicology should assist in an improvement, both in the epidemiology of toxicity in South Africa and in improved measures to reduce the incidence of preventable noncommunicable diseases related to both acute and chronic exposure to toxins. The South African scene also provides a "window' of opportunity to study the more fundamental aspects of exposure in human subjects and to couple these to animal and in vitro studies to elucidate the underlying mechanisms where these are unknown. PMID:11805740

  17. Ebola in West Africa.

    PubMed

    Raka, Lul; Guardo, Monica

    2015-03-15

    Ebola viral disease (EVD) is a severe and life-threatening disease. The current Ebola outbreak in West Africa entered its second year and is unprecedented because it is the largest one in history, involved urban centers and affected a large number of health care workers. It quickly escalated from medical into a humanitarian, social, economic, and security crisis. The primary pillars to prevent EVD are: early diagnosis, isolation of patients, contact tracing and monitoring, safe burials, infection prevention and control and social mobilization. The implementation of all these components was challenged in the field. Key lessons from this Ebola outbreak are that countries with weak health care systems can't withstand the major outbreaks; preparedness to treat the first confirmed cases is a national emergency; all control measures must be coordinated together and community engagement is the great factor to combat this disease.

  18. The use of direct sequencing of dengue virus cDNA from individual field-collected Aedes aegypti for surveillance and epidemiological studies.

    PubMed

    Romero-Vivas, C M; Sutherland, C J; Falconar, A K

    2000-03-01

    The relative efficiencies of four methods to extract viral RNA from individual dengue-2 virus (D-2V)-infected mosquitoes, Aedes aegypti (L.) (Diptera: Culicidae), were compared. The most efficient of these methods was then used to extract viral RNA for the preparation of cDNA from the abdomens of six engorged D-2V-infected mosquitoes and sera from three dengue fever (DF) patients collected in an isolated rural town in Colombia. Comparisons of viral envelope (E) gene sequences from each of these strongly suggested that the D-2V population which circulated in this study area was a homogeneous genotype which was unrelated to any of the D-2 viruses isolated from elsewhere in the world. When coupled with our rapid method to identify viruses in individual mosquitoes (Romero-Vivas et al. (1998) Medical and Veterinary Entomology, 12, 101-105), the methodology we describe should be useful for epidemiological and surveillance studies of dengue viruses and other arboviruses.

  19. [Molecular epidemiology in the epidemiological transition].

    PubMed

    Tapia-Conyer, R

    1997-01-01

    The epidemiological transition describes the changes in the health profile of populations where infectious diseases are substituted by chronic or non-communicable diseases. Even in industrialized countries, infectious diseases emerge as important public health problems and with a very important association with several type of neoplasm. Molecular epidemiology brings in new tools for the study of the epidemiological transition by discovering infectious agents as etiology of diseases, neither of both new. Much has been advanced in the understanding of the virulence and resistance mechanism of different strains, or improving the knowledge on transmission dynamics and dissemination pathways of infectious diseases. As to the non-communicable diseases, molecular epidemiology has enhanced the identification of endogenous risk factors link to alterations, molecular changes in genetic material, that will allow a more detail definition of risk and the identification of individual and groups at risk of several diseases. The potential impact of molecular epidemiology in other areas as environmental, lifestyles and nutritional areas are illustrated with several examples. PMID:9504120

  20. Atmospheric chemistry over southern Africa

    NASA Astrophysics Data System (ADS)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2012-03-01

    Changing Chemistry in a Changing Climate: Human and Natural Impacts Over Southern Africa (C4-SAR); Midrand, South Africa, 31 May to 3 June 2011 During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semipermanent atmospheric gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite- derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission on Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from Eskom, the South African power utility; and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa.

  1. Understanding the molecular epidemiology of foot-and-mouth-disease virus.

    PubMed

    Klein, Joern

    2009-03-01

    The use of molecular epidemiology is an important tool in understanding and consequently controlling FMDV. In this review I will present basic information about the disease, needed to perform molecular epidemiology. I will give a short introduction to the history and impact of foot-and-mouth disease, clinical picture, infection route, subclinical and persistent infections, general aspects of the transmission of FMDV, serotype-specific epidemiological characteristics, field epidemiology of FMDV, evolution and molecular epidemiology of FMDV. This is followed by two chapters describing the molecular epidemiology of foot-and-mouth disease in global surveillance and molecular epidemiology of foot-and-mouth disease in outbreak investigation.

  2. "Epidemiological criminology": coming full circle.

    PubMed

    Akers, Timothy A; Lanier, Mark M

    2009-03-01

    Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose "epidemiological criminology" as a bridging framework.

  3. Development of reference transcriptomes for the major field insect pests of cowpea: a toolbox for insect pest management approaches in west Africa.

    PubMed

    Agunbiade, Tolulope A; Sun, Weilin; Coates, Brad S; Djouaka, Rousseau; Tamò, Manuele; Ba, Malick N; Binso-Dabire, Clementine; Baoua, Ibrahim; Olds, Brett P; Pittendrigh, Barry R

    2013-01-01

    Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae). Efforts to control these pests remain a challenge and there is a need to understand the structure and movement of these pest populations in order to facilitate the development of integrated pest management strategies (IPM). Molecular tools have the potential to help facilitate a better understanding of pest populations. Towards this goal, we used 454 pyrosequencing technology to generate 319,126, 176,262, 320,722 and 227,882 raw reads from A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. The reads were de novo assembled into 11,687, 7,647, 10,652 and 7,348 transcripts for A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. Functional annotation of the resulting transcripts identified genes putatively involved in insecticide resistance, pathogen defense and immunity. Additionally, sequences that matched the primary aphid endosymbiont, Buchnera aphidicola, were identified among A. craccivora transcripts. Furthermore, 742, 97, 607 and 180 single nucleotide polymorphisms (SNPs) were respectively predicted among A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti transcripts, and will likely be valuable tools for future molecular genetic marker development. These results demonstrate that Roche 454-based transcriptome sequencing could be useful for the development of genomic resources for cowpea pest insects in West Africa. PMID:24278221

  4. Development of Reference Transcriptomes for the Major Field Insect Pests of Cowpea: A Toolbox for Insect Pest Management Approaches in West Africa

    PubMed Central

    Agunbiade, Tolulope A.; Sun, Weilin; Coates, Brad S.; Djouaka, Rousseau; Tamò, Manuele; Ba, Malick N.; Binso-Dabire, Clementine; Baoua, Ibrahim; Olds, Brett P.; Pittendrigh, Barry R.

    2013-01-01

    Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae). Efforts to control these pests remain a challenge and there is a need to understand the structure and movement of these pest populations in order to facilitate the development of integrated pest management strategies (IPM). Molecular tools have the potential to help facilitate a better understanding of pest populations. Towards this goal, we used 454 pyrosequencing technology to generate 319,126, 176,262, 320,722 and 227,882 raw reads from A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. The reads were de novo assembled into 11,687, 7,647, 10,652 and 7,348 transcripts for A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. Functional annotation of the resulting transcripts identified genes putatively involved in insecticide resistance, pathogen defense and immunity. Additionally, sequences that matched the primary aphid endosymbiont, Buchnera aphidicola, were identified among A. craccivora transcripts. Furthermore, 742, 97, 607 and 180 single nucleotide polymorphisms (SNPs) were respectively predicted among A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti transcripts, and will likely be valuable tools for future molecular genetic marker development. These results demonstrate that Roche 454-based transcriptome sequencing could be useful for the development of genomic resources for cowpea pest insects in West Africa. PMID:24278221

  5. Recruiting minorities into the profession of epidemiology. Surveying the applicants' mail. American College of Epidemiology Committee on Minority Affairs.

    PubMed

    Morssink, C B; Kumanyika, S; Tell, G S; Schoenbach, V J

    1996-01-01

    The underrepresentation in epidemiology of members of racial/ethnic minority groups is greater than in medicine and health fields in general. Using printed recruitment materials, we evaluated the impression that epidemiology programs might make on prospective minority students. Mainstream recruitment materials were solicited from all identifiable U.S. epidemiology programs (n = 70) by requesting copies of typical mailings to prospective students. Of 51 respondents, 46 sent materials that could be analyzed by tabulating and evaluating minority-related content in text and pictures. Materials reflected a generally low-key approach to epidemiology student recruitment. Most minority-related text referred to affirmative action or financial aid and was at the school level rather than specific to the epidemiology programs. Few minority-related epidemiology course titles or research interests were identified. We recommend including more information about epidemiology and its relevance to minority health in mainstream recruitment materials as one possible strategy for increasing the number of minority applicants.

  6. Risk Factors for Low Back Disorders in Saskatchewan Farmers: Field-based Exposure Assessment to Build a Foundation for Epidemiological Studies

    PubMed Central

    Bath, Brenna; Johnson, Peter W; Teschke, Kay

    2016-01-01

    Background Studies of many geographical settings and agricultural commodities show that low back disorders are an important public health issue among farmers, who represent a special rural population. However, few studies have examined the impact of low back disorders on farmers’ work or the strategies that they adopt to avoid associated pain and disability. Objective This study protocol will investigate 3 issues related to low back disorders in Saskatchewan farmers: (1) the vibration, heavy lifting, and awkward postures farmers encounter during their work that might contribute to low back disorders; (2) the impact low back disorders have on farmers in terms of their ability to work; and (3) the types of preventative measures and solutions that farmers implement to reduce the occurrence of low back pain. Methods To answer these questions, researchers will travel to 30 farms to make measurements of vibration, lifting, and posture during the farmers’ regular work tasks. Farmers will be interviewed about any pain and/or disability using standardized interview questions. Farmers will also be asked about safety measures they have implemented at their farm, such as modified tools or equipment, to reduce the occurrence of low back disorders or pain. Results Data collection is currently underway for this study, with the intention to complete all data collection and analysis by the end of 2018. Conclusions Occupational determinants of health such as vibration, heavy lifting, and awkward postures are important in the development and progression of low back disorders, and the results of this study will allow for cost-effective epidemiological studies of these determinants in the future. In identifying prevention strategies, this study will also facilitate future research evaluating the effectiveness of safety measures. PMID:27286748

  7. East Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image shows the East African nations of Ethiopia, Eritrea, and Somalia, as well as portions of Kenya, Sudan, Yemen, and Saudi Arabia. Dominating the scene are the green Ethiopian Highlands. With altitudes as high as 4,620 meters (15,157 feet), the highlands pull moisture from the arid air, resulting in relatively lush vegetation. In fact, coffee-one of the world's most prized crops-originated here. To the north (above) the highlands is Eritrea, which became independent in 1993. East (right) of Ethiopia is Somalia, jutting out into the Indian Ocean. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) captured this true-color image on November 29, 2000. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  8. Vaccine epidemiology: A review

    PubMed Central

    Lahariya, Chandrakant

    2016-01-01

    This review article outlines the key concepts in vaccine epidemiology, such as basic reproductive numbers, force of infection, vaccine efficacy and effectiveness, vaccine failure, herd immunity, herd effect, epidemiological shift, disease modeling, and describes the application of this knowledge both at program levels and in the practice by family physicians, epidemiologists, and pediatricians. A case has been made for increased knowledge and understanding of vaccine epidemiology among key stakeholders including policy makers, immunization program managers, public health experts, pediatricians, family physicians, and other experts/individuals involved in immunization service delivery. It has been argued that knowledge of vaccine epidemiology which is likely to benefit the society through contributions to the informed decision-making and improving vaccination coverage in the low and middle income countries (LMICs). The article ends with suggestions for the provision of systematic training and learning platforms in vaccine epidemiology to save millions of preventable deaths and improve health outcomes through life-course. PMID:27453836

  9. Vaccine epidemiology: A review.

    PubMed

    Lahariya, Chandrakant

    2016-01-01

    This review article outlines the key concepts in vaccine epidemiology, such as basic reproductive numbers, force of infection, vaccine efficacy and effectiveness, vaccine failure, herd immunity, herd effect, epidemiological shift, disease modeling, and describes the application of this knowledge both at program levels and in the practice by family physicians, epidemiologists, and pediatricians. A case has been made for increased knowledge and understanding of vaccine epidemiology among key stakeholders including policy makers, immunization program managers, public health experts, pediatricians, family physicians, and other experts/individuals involved in immunization service delivery. It has been argued that knowledge of vaccine epidemiology which is likely to benefit the society through contributions to the informed decision-making and improving vaccination coverage in the low and middle income countries (LMICs). The article ends with suggestions for the provision of systematic training and learning platforms in vaccine epidemiology to save millions of preventable deaths and improve health outcomes through life-course. PMID:27453836

  10. [Depression in Sub-Saharan Africa].

    PubMed

    Perez, S; Junod, A

    1998-01-01

    We now have a better knowledge of the specific features of depression in sub-Saharan Africa. Anthropologically speaking, the Western model is irrelevant. Depression in sub-Saharan Africa involves the relationship of the subject to himself or others in a mode specific to African cultures. Ignoring this fact can lead to simplistic ethnocentrism. From a clinical standpoint, depressive illness characterized by somatic manifestations, delusions of persecution, and anxiety are increasingly uncommon. As African societies modernize, these traditional forms are being gradually supplanted by states with symptoms and prognoses more like those observed in industrialized countries. Hybrid depressive syndromes are now the most widespread. Epidemiologically the notion widely held only a few decades ago that depression is a rare occurrence in Africa has now been dispelled. Many studies have been conducted to determine the exact incidence, age distribution, and sex ratio but more precise data is still needed. This investigation will require improvement in screening and diagnostic methods which must be not only suitable for clinical use but also adaptable to local conditions. This is also true with regard to management which has the same goals as anywhere else in the world. Treatment facilities are different in urban and rural areas but care is often dispensed in unconventional settings and may be combined with traditional methods. Drug availability is limited by problems involving supply and cost. This explains why electro-convulsive therapy which was introduced into sub-Saharan Africa long ago still plays a major role in the treatment of depression.

  11. It's about TIME: engendering AIDS in Africa.

    PubMed

    Brijnath, Bianca

    2007-01-01

    This paper analyses how TIME magazine represents sub-Saharan African women in its coverage of HIV/AIDS. As rates of infection escalate across the continent, researchers are increasingly emphasising the need to understand the socioeconomic and cultural contexts that make women particularly vulnerable to infection. Yet popular media representations of AIDS continue to rely on older colonial imageries of Africa as the feminised, diseased 'dark continent'. This article identifies three major themes in TIME's representation of sub-Saharan African women and HIV/AIDS: the metaphor of Africa as a woman in crisis, the construction of women as the means of transmission, and the engendered nature of the debate about the impact of international development policies. It is argued that the reliance on familiar cultural narratives often obscures the epidemiological, economic and cultural realities within which sub-Saharan women live. Not merely a consequence of unprotected sex, AIDS in sub-Saharan Africa is also the result of global economics and politics, reflecting the inequities between the West and Africa, male and female, white and black. The paper concludes with a call for further research on the role of representations of HIV/AIDS and its actual routes of transmission. PMID:17612957

  12. It's about TIME: engendering AIDS in Africa.

    PubMed

    Brijnath, Bianca

    2007-01-01

    This paper analyses how TIME magazine represents sub-Saharan African women in its coverage of HIV/AIDS. As rates of infection escalate across the continent, researchers are increasingly emphasising the need to understand the socioeconomic and cultural contexts that make women particularly vulnerable to infection. Yet popular media representations of AIDS continue to rely on older colonial imageries of Africa as the feminised, diseased 'dark continent'. This article identifies three major themes in TIME's representation of sub-Saharan African women and HIV/AIDS: the metaphor of Africa as a woman in crisis, the construction of women as the means of transmission, and the engendered nature of the debate about the impact of international development policies. It is argued that the reliance on familiar cultural narratives often obscures the epidemiological, economic and cultural realities within which sub-Saharan women live. Not merely a consequence of unprotected sex, AIDS in sub-Saharan Africa is also the result of global economics and politics, reflecting the inequities between the West and Africa, male and female, white and black. The paper concludes with a call for further research on the role of representations of HIV/AIDS and its actual routes of transmission.

  13. The atmospheric circulation over West Africa and equatorial Africa

    NASA Astrophysics Data System (ADS)

    Grist, Jeremy Peter

    2000-11-01

    The atmospheric circulation over West Africa and equatorial Africa is examined with two objectives in mind. The first goal is to determine the features of the circulation that distinguish a wet spell from a dry spell. The second is to examine how these differences affect the African Easterly Waves that traverse the region. The study utilizes the new NCEP reanalysis product. This new data set is compared with other sources of data and evaluated for West Africa. The mean annual cycle (1958-97) of the basic state and the easterly disturbances were examined using 40 years of NCEP reanalysis data. The results suggest that there is a seasonal dependence in the dominant shear instability mechanism. This seasonal shift in the instability mechanism may produce a similar seasonal change in the structure of the African Easterly Waves. Composites of atmospheric fields for four wet years (1958-61) were compared to those of four dry years (1982-85). Important differences were noted in the wind, temperature, and humidity fields. In particular, wet years were characterized by a stronger monsoonal flow, a stronger Tropical Easterly Jet, and a more northerly African Easterly Jet. Similarly, differences in the AEWs between wet and dry years were examined. It was found that the wave season in wet years tended to be longer, more active, and composed of stronger waves. In addition, the wave structure exhibited a greater seasonal dependence in wet years.

  14. Traditional epidemiology, modern epidemiology, and public health.

    PubMed Central

    Pearce, N

    1996-01-01

    There have been significant developments in epidemiologic methodology during the past century, including changes in basic concepts, methods of data analysis, and methods of exposure measurement. However, the rise of modern epidemiology has been a mixed blessing, and the new paradigm has major shortcomings, both in public health and in scientific terms. The changes in the paradigm have not been neutral but have rather helped change--and have reflected changes in--the way in which epidemiologists think about health and disease. The key issue has been the shift in the level of analysis from the population to the individual. Epidemiology has largely ceased to function as part of a multidisciplinary approach to understanding the causation of disease in populations and has become a set of generic methods for measuring associations of exposure and disease in individuals. This reductionist approach focuses on the individual, blames the victim, and produces interventions that can be harmful. We seem to be using more and more advanced technology to study more and more trivial issues, while the major causes of disease are ignored. Epidemiology must reintegrate itself into public health and must rediscover the population perspective. PMID:8629719

  15. Characterization of epidemiologically unrelated Acinetobacter baumannii isolates from four continents by use of multilocus sequence typing, pulsed-field gel electrophoresis, and sequence-based typing of bla(OXA-51-like) genes.

    PubMed

    Hamouda, Ahmed; Evans, Benjamin A; Towner, Kevin J; Amyes, Sebastian G B

    2010-07-01

    This study used a diverse collection of epidemiologically unrelated Acinetobacter baumannii isolates to compare the robustness of a multilocus sequence typing (MLST) scheme, based on conserved regions of seven housekeeping genes, gltA, gdhB, recA, cpn60, rpoD, gyrB, and gpi, with that of sequence-based typing of bla(OXA-51-like) genes (SBT-bla(OXA-51-like) genes). The data obtained by analysis of MLST and SBT-bla(OXA-51-like) genes were compared to the data generated by pulsed-field gel electrophoresis (PFGE). The topologies of the phylogenetic trees generated for the gyrB and gpi genes showed evidence of recombination and were inconsistent with those of the trees generated for the other five genes. MLST identified 24 sequence types (STs), of which 19 were novel, and 5 novel alleles. Clonality was demonstrated by eBURST analysis and standardized index of association values of >1 (P < 0.001). MLST data revealed that all isolates harboring the major bla(OXA-51-like) alleles OXA-66, OXA-69, and OXA-71 fell within the three major European clonal lineages. However, the MLST data were not always in concordance with the PFGE data, and some isolates containing the same bla(OXA-51-like) allele demonstrated <50% relatedness by PFGE. It was concluded that the gyrB and gpi genes are not good candidates for use in MLST analysis and that a SBT-bla(OXA-51-like) gene scheme produced results comparable to those produced by MLST for the identification of the major epidemic lineages, with the advantage of having a significantly reduced sequencing cost and time. It is proposed that studies of A. baumannii epidemiology could involve initial screening of bla(OXA-51-like) alleles to identify isolates belonging to major epidemic lineages, followed by MLST analysis to categorize isolates from common lineages, with PFGE being reserved for fine-scale typing.

  16. Epidemiology of human African trypanosomiasis

    PubMed Central

    Franco, Jose R; Simarro, Pere P; Diarra, Abdoulaye; Jannin, Jean G

    2014-01-01

    Human African trypanosomiasis (HAT), or sleeping sickness, is caused by Trypanosoma brucei gambiense, which is a chronic form of the disease present in western and central Africa, and by Trypanosoma brucei rhodesiense, which is an acute disease located in eastern and southern Africa. The rhodesiense form is a zoonosis, with the occasional infection of humans, but in the gambiense form, the human being is regarded as the main reservoir that plays a key role in the transmission cycle of the disease. The gambiense form currently assumes that 98% of the cases are declared; the Democratic Republic of the Congo is the most affected country, with more than 75% of the gambiense cases declared. The epidemiology of the disease is mediated by the interaction of the parasite (trypanosome) with the vectors (tsetse flies), as well as with the human and animal hosts within a particular environment. Related to these interactions, the disease is confined in spatially limited areas called “foci”, which are located in Sub-Saharan Africa, mainly in remote rural areas. The risk of contracting HAT is, therefore, determined by the possibility of contact of a human being with an infected tsetse fly. Epidemics of HAT were described at the beginning of the 20th century; intensive activities have been set up to confront the disease, and it was under control in the 1960s, with fewer than 5,000 cases reported in the whole continent. The disease resurged at the end of the 1990s, but renewed efforts from endemic countries, cooperation agencies, and nongovernmental organizations led by the World Health Organization succeeded to raise awareness and resources, while reinforcing national programs, reversing the trend of the cases reported, and bringing the disease under control again. In this context, sustainable elimination of the gambiense HAT, defined as the interruption of the transmission of the disease, was considered as a feasible target for 2030. Since rhodesiense HAT is a zoonosis

  17. Diet, Genetics, and Disease: A Focus on the Middle East and North Africa Region

    PubMed Central

    Fahed, Akl C.; El-Hage-Sleiman, Abdul-Karim M.; Farhat, Theresa I.; Nemer, Georges M.

    2012-01-01

    The Middle East and North Africa (MENA) region suffers a drastic change from a traditional diet to an industrialized diet. This has led to an unparalleled increase in the prevalence of chronic diseases. This review discusses the role of nutritional genomics, or the dietary signature, in these dietary and disease changes in the MENA. The diet-genetics-disease relation is discussed in detail. Selected disease categories in the MENA are discussed starting with a review of their epidemiology in the different MENA countries, followed by an examination of the known genetic factors that have been reported in the disease discussed, whether inside or outside the MENA. Several diet-genetics-disease relationships in the MENA may be contributing to the increased prevalence of civilization disorders of metabolism and micronutrient deficiencies. Future research in the field of nutritional genomics in the MENA is needed to better define these relationships. PMID:22536488

  18. Epidemiological studies in psychosomatic medicine.

    PubMed

    Eastwood, M R

    1975-01-01

    The epidemiological triad of host, agent and environment used conceptually in infectious disease may serve as a model for psychosomatic disorders, despite the involvement of many more variables. There are major problems with diagnosis and measurement, however, and the term "psychosomatic" has several meanings. The two main senses are "specific" psychosomatic disorders and an ecological view of illness. The association between psychiatric and physical disorder has been examined in a variety of settings and the findings have suggested that there is a positive relationship. Despite considerable methodological and sampling difficulties in epidemiological research into psychosomatic illness, recent efforts have been made to overcome these. The results of ecological studies appear to be more consistent that those dealing with "specific" psychosomatic disorders and suggest that man has a general psychophysical propensity to disease. Although physical and mental illness do seem to be intimately linked, the reasons for "vulnerability" to illness and "clustering" of illness are obscure. The clarification of these areas appears to be the main task ahead for epidemiology in the field of psychosomatic medicine. PMID:773850

  19. Africa: the emphasis is exploration

    SciTech Connect

    Not Available

    1980-08-15

    Individual country reports on drilling, oil and gas production, and petroleum exploration and reserves are given for Africa. Nigeria was the continent's largest oil producer in 1979, averaging 2.3 million bpd, followed closely by Libya with 2.07 million bpd. Algeria cut production of crude oil in 1979 to a level of 1,194,350 bpd, and increased gas production to 2031 mmcfd. In Egypt, the return of Israeli-occupied oil fields and a surge in productive capacity enabled production averaging 524,000 bpd. Brief country reports are included for Gabon, Angola, Republic of the Congo, Cameroun, Tunisia, Morocco, Zaire, Ivory Coast, Ghana, Niger, Chad, Republic of South Africa, Sudan, Tanzania, Equatorial Guinea, Seychelles Islands, Mauritania, Republic of Mali, Benin, Kenya, Madagascar, Botswana, Gambia, Mozambique, and Senegal.

  20. Genomic epidemiology of artemisinin resistant malaria

    PubMed Central

    2016-01-01

    The current epidemic of artemisinin resistant Plasmodium falciparum in Southeast Asia is the result of a soft selective sweep involving at least 20 independent kelch13 mutations. In a large global survey, we find that kelch13 mutations which cause resistance in Southeast Asia are present at low frequency in Africa. We show that African kelch13 mutations have originated locally, and that kelch13 shows a normal variation pattern relative to other genes in Africa, whereas in Southeast Asia there is a great excess of non-synonymous mutations, many of which cause radical amino-acid changes. Thus, kelch13 is not currently undergoing strong selection in Africa, despite a deep reservoir of variations that could potentially allow resistance to emerge rapidly. The practical implications are that public health surveillance for artemisinin resistance should not rely on kelch13 data alone, and interventions to prevent resistance must account for local evolutionary conditions, shown by genomic epidemiology to differ greatly between geographical regions. DOI: http://dx.doi.org/10.7554/eLife.08714.001 PMID:26943619

  1. Genomic epidemiology of artemisinin resistant malaria.

    PubMed

    2016-01-01

    The current epidemic of artemisinin resistant Plasmodium falciparum in Southeast Asia is the result of a soft selective sweep involving at least 20 independent kelch13 mutations. In a large global survey, we find that kelch13 mutations which cause resistance in Southeast Asia are present at low frequency in Africa. We show that African kelch13 mutations have originated locally, and that kelch13 shows a normal variation pattern relative to other genes in Africa, whereas in Southeast Asia there is a great excess of non-synonymous mutations, many of which cause radical amino-acid changes. Thus, kelch13 is not currently undergoing strong selection in Africa, despite a deep reservoir of variations that could potentially allow resistance to emerge rapidly. The practical implications are that public health surveillance for artemisinin resistance should not rely on kelch13 data alone, and interventions to prevent resistance must account for local evolutionary conditions, shown by genomic epidemiology to differ greatly between geographical regions. PMID:26943619

  2. SERVIR-Africa: Developing an Integrated Platform for Floods Disaster Management in Africa

    NASA Technical Reports Server (NTRS)

    Macharia, Daniel; Korme, Tesfaye; Policelli, Fritz; Irwin, Dan; Adler, Bob; Hong, Yang

    2010-01-01

    SERVIR-Africa is an ambitious regional visualization and monitoring system that integrates remotely sensed data with predictive models and field-based data to monitor ecological processes and respond to natural disasters. It aims addressing societal benefits including floods and turning data into actionable information for decision-makers. Floods are exogenous disasters that affect many parts of Africa, probably second only to drought in terms of social-economic losses. This paper looks at SERVIR-Africa's approach to floods disaster management through establishment of an integrated platform, floods prediction models, post-event flood mapping and monitoring as well as flood maps dissemination in support of flood disaster management.

  3. Epidemiology of Crohn's Disease.

    PubMed

    Sandler, R S; Golden, A L

    1986-04-01

    Although our current understanding is limited, epidemiologic investigation of Crohn's disease holds great promise. Certain aspects of the epidemiology are clear. The incidence of Crohn's disease, which has increased over the past few decades, may have reached a plateau. The disease has its peak onset in early life, with a second peak among the elderly. It is more common in the developed countries and among Jews. Whether the disease is related to occupation, social class, marital status, stress, infection, diet, smoking, and oral contraceptives is less certain. This paper reviews the epidemiology of Crohn's disease and proposes areas in which further research is needed.

  4. Evolution and social epidemiology.

    PubMed

    Nishi, Akihiro

    2015-11-01

    Evolutionary biology, which aims to explain the dynamic process of shaping the diversity of life, has not yet significantly affected thinking in social epidemiology. Current challenges in social epidemiology include understanding how social exposures can affect our biology, explaining the dynamics of society and health, and designing better interventions that are mindful of the impact of exposures during critical periods. I review how evolutionary concepts and tools, such as fitness gradient in cultural evolution, evolutionary game theory, and contemporary evolution in cancer, can provide helpful insights regarding social epidemiology.

  5. Global Epidemiology of Campylobacter Infection

    PubMed Central

    Kaakoush, Nadeem O.; Castaño-Rodríguez, Natalia; Mitchell, Hazel M.

    2015-01-01

    SUMMARY Campylobacter jejuni infection is one of the most widespread infectious diseases of the last century. The incidence and prevalence of campylobacteriosis have increased in both developed and developing countries over the last 10 years. The dramatic increase in North America, Europe, and Australia is alarming, and data from parts of Africa, Asia, and the Middle East indicate that campylobacteriosis is endemic in these areas, especially in children. In addition to C. jejuni, there is increasing recognition of the clinical importance of emerging Campylobacter species, including Campylobacter concisus and Campylobacter ureolyticus. Poultry is a major reservoir and source of transmission of campylobacteriosis to humans. Other risk factors include consumption of animal products and water, contact with animals, and international travel. Strategic implementation of multifaceted biocontrol measures to reduce the transmission of this group of pathogens is paramount for public health. Overall, campylobacteriosis is still one of the most important infectious diseases that is likely to challenge global health in the years to come. This review provides a comprehensive overview of the global epidemiology, transmission, and clinical relevance of Campylobacter infection. PMID:26062576

  6. Ebola virus outbreaks in Africa: past and present.

    PubMed

    Muyembe-Tamfum, J J; Mulangu, S; Masumu, Justin; Kayembe, J M; Kemp, A; Paweska, Janusz T

    2012-01-01

    Ebola haemorrhagic fever (EHF) is a zoonosis affecting both human and non-human primates (NHP). Outbreaks in Africa occur mainly in the Congo and Nile basins. The first outbreaks of EHF occurred nearly simultaneously in 1976 in the Democratic Republic of the Congo (DRC, former Zaire) and Sudan with very high case fatality rates of 88% and 53%, respectively. The two outbreaks were caused by two distinct species of Ebola virus named Zaire ebolavirus (ZEBOV) and Sudan ebolavirus (SEBOV). The source of transmission remains unknown. After a long period of silence (1980-1993), EHF outbreaks in Africa caused by the two species erupted with increased frequency and new species were discovered, namely Côte d'Ivoire ebolavirus (CIEBOV) in 1994 in the Ivory Coast and Bundibugyo ebolavirus (BEBOV) in 2007 in Uganda. The re-emergence of EHF outbreaks in Gabon and Republic of the Congo were concomitant with an increase in mortality amongst gorillas and chimpanzees infected with ZEBOV. The human outbreaks were related to multiple, unrelated index cases who had contact with dead gorillas or chimpanzees. However, in areas where NHP were rare or absent, as in Kikwit (DRC) in 1995, Mweka (DRC) in 2007, Gulu (Uganda) in 2000 and Yambio (Sudan) in 2004, the hunting and eating of fruit bats may have resulted in the primary transmission of Ebola virus to humans. Human-to-human transmission is associated with direct contact with body fluids or tissues from an infected subject or contaminated objects. Despite several, often heroic field studies, the epidemiology and ecology of Ebola virus, including identification of its natural reservoir hosts, remains a formidable challenge for public health and scientific communities. PMID:23327370

  7. Networks and the Epidemiology of Infectious Disease

    PubMed Central

    Danon, Leon; Ford, Ashley P.; House, Thomas; Jewell, Chris P.; Keeling, Matt J.; Roberts, Gareth O.; Ross, Joshua V.; Vernon, Matthew C.

    2011-01-01

    The science of networks has revolutionised research into the dynamics of interacting elements. It could be argued that epidemiology in particular has embraced the potential of network theory more than any other discipline. Here we review the growing body of research concerning the spread of infectious diseases on networks, focusing on the interplay between network theory and epidemiology. The review is split into four main sections, which examine: the types of network relevant to epidemiology; the multitude of ways these networks can be characterised; the statistical methods that can be applied to infer the epidemiological parameters on a realised network; and finally simulation and analytical methods to determine epidemic dynamics on a given network. Given the breadth of areas covered and the ever-expanding number of publications, a comprehensive review of all work is impossible. Instead, we provide a personalised overview into the areas of network epidemiology that have seen the greatest progress in recent years or have the greatest potential to provide novel insights. As such, considerable importance is placed on analytical approaches and statistical methods which are both rapidly expanding fields. Throughout this review we restrict our attention to epidemiological issues. PMID:21437001

  8. Foot-and-mouth Disease Transmission in Africa: Implications for Control, a Review.

    PubMed

    Tekleghiorghis, T; Moormann, R J M; Weerdmeester, K; Dekker, A

    2016-04-01

    In Africa, for the control of foot-and-mouth disease (FMD), more information is needed on the spread of the disease at local, regional and inter-regional level. The aim of this review is to identify the role that animal husbandry, trade and wildlife have on the transmission of FMD and to provide a scientific basis for different FMD control measures in Africa. Review of literature, published reports and databases shows that there is more long distance spread of FMD virus serotypes within North, West, Central and East Africa than in southern Africa. In North, West, Central and East Africa migratory animal husbandry systems often related with search for grazing and water as well as trade are practiced to a greater extent than in southern Africa. In southern Africa, the role of African buffalo (Syncerus caffer) is more extensively studied than in the other parts of Africa, but based on the densities of African buffalo in Central and East Africa, one would assume that buffalo should also play a role in the epidemiology of FMD in this part of Africa. More sampling of buffalo is necessary in West, Central and East Africa. The genetic analysis of virus strains has proven to be valuable to increase our understanding in the spread of FMD in Africa. This review shows that there is a difference in FMD occurrence between southern Africa and the rest of the continent; this distinction is most likely based on differences in animal husbandry and trade systems. Insufficient data on FMD in wildlife outside southern Africa is limiting our understanding on the role wildlife plays in the transmission of FMD in the other buffalo inhabited areas of Africa.

  9. [DOHaD: epidemiological researches].

    PubMed

    Delpierre, Cyrille; Lepeule, Johanna; Cordier, Sylvaine; Slama, Remy; Heude, Barbara; Charles, Marie-Aline

    2016-01-01

    Epidemiological researches in the field of DOHaD are in favor of a role of early environment, including chemical (pesticides), physical (air pollution), nutritional or psychosocial environment, on child and adult health. Disentangling the different factors of environment that may affect health, especially over time, and identifying critical periods of exposure remains a major challenge. The biological mechanisms involved remain elusive in human beings. Nevertheless, it seems that whatever the nature of the exposure, epigenetic mechanisms are currently discussed to explain how the environment may alter biological systems over time.

  10. EPIDEMIOLOGY AND EXPOSURE ASSESSMENT

    EPA Science Inventory

    Research collaborations between the National Health and Environmental Effects Research Laboratory (NHEERL) and the National Exposure Research Laboratory (NERL) centered on the development and application of exposure analysis tools in environmental epidemiology include the El Paso...

  11. Epidemiology of varicocele

    PubMed Central

    Alsaikhan, Bader; Alrabeeah, Khalid; Delouya, Guila; Zini, Armand

    2016-01-01

    Varicocele is a common problem in reproductive medicine practice. A varicocele is identified in 15% of healthy men and up to 35% of men with primary infertility. The exact pathophysiology of varicoceles is not very well understood, especially regarding its effect on male infertility. We have conducted a systematic review of studies evaluating the epidemiology of varicocele in the general population and in men presenting with infertility. In this article, we have identified some of the factors that can influence the epidemiological aspects of varicoceles. We also recognize that varicocele epidemiology remains incompletely understood, and there is a need for well-designed, large-scale studies to fully define the epidemiological aspects of this condition. PMID:26763551

  12. Epidemiology & Genomics Research Program

    Cancer.gov

    The Epidemiology and Genomics Research Program, in the National Cancer Institute's Division of Cancer Control and Population Sciences, funds research in human populations to understand the determinants of cancer occurrence and outcomes.

  13. Epidemiology of Lice

    ERIC Educational Resources Information Center

    Juranek, Dennis D.

    1977-01-01

    Research into the epidemiology of lice indicates that infestation is uncommon in blacks, more common in females than males, significantly higher in low income groups, and transmission is by way of articles of clothing. (JD)

  14. Cancer Epidemiology Cohorts

    Cancer.gov

    Cohort studies are fundamental for epidemiological research by helping researchers better understand the etiology of cancer and provide insights into the key determinants of this disease and its outcomes.

  15. The Impact of Inventory Management on Stock-Outs of Essential Drugs in Sub-Saharan Africa: Secondary Analysis of a Field Experiment in Zambia

    PubMed Central

    Leung, Ngai-Hang Z.; Chen, Ana; Yadav, Prashant; Gallien, Jérémie

    2016-01-01

    Objective To characterize the impact of widespread inventory management policies on stock-outs of essential drugs in Zambia’s health clinics and develop related recommendations. Methods Daily clinic storeroom stock levels of artemether-lumefantrine (AL) products in 2009–2010 were captured in 145 facilities through photography and manual transcription of paper forms, then used to determine historical stock-out levels and estimate demand patterns. Delivery lead-times and estimates of monthly facility accessibility were obtained through worker surveys. A simulation model was constructed and validated for predictive accuracy against historical stock-outs, then used to evaluate various changes potentially affecting product availability. Findings While almost no stock-outs of AL products were observed during Q4 2009 consistent with primary analysis, up to 30% of surveyed facilities stocked out of some AL product during Q1 2010 despite ample inventory being simultaneously available at the national warehouse. Simulation experiments closely reproduced these results and linked them to the use of average past monthly issues and failure to capture lead-time variability in current inventory control policies. Several inventory policy enhancements currently recommended by USAID | DELIVER were found to have limited impact on product availability. Conclusions Inventory control policies widely recommended and used for distributing medicines in sub-Saharan Africa directly account for a substantial fraction of stock-outs observed in common situations involving demand seasonality and facility access interruptions. Developing central capabilities in peripheral demand forecasting and inventory control is critical. More rigorous independent peer-reviewed research on pharmaceutical supply chain management in low-income countries is needed. PMID:27227412

  16. Epidemiologists, social scientists, and the structure of medical research on AIDS in Africa.

    PubMed

    Packard, R M; Epstein, P

    1991-01-01

    The development of medical research on AIDS in Africa resembles earlier efforts to understand the epidemiology of TB and syphilis in Africa. In all three cases early research focused on why these diseases exhibited different epidemiological patterns in Africa than in the west. Early explanations of these differences focused on the peculiarities of African behavior, while largely excluding from vision a range of environmental factors. These parallels provide a framework for examining how western ideas about AIDS in Africa developed, the role of social scientists in the formation of these ideas, and how these initial perceptions shaped the subsequent development of AIDS research, encouraging a premature narrowing of research questions. The paper warns that, as in the histories of TB and syphilis research, this early closure may generate inadequate and inappropriate responses to the African AIDS epidemic and limit our understanding of the disease.

  17. [Molecular and genetic epidemiology].

    PubMed

    Kang, D H

    2001-04-21

    Molecular epidemiology is defined as "the use of biological markers in epidemiologic research" and genetic epidemiology is defined as "the study of the interaction between genetic and environmental factors in epidemiologic research". Traditional epidemiologic approaches defined as "the study of the distribution and determinants of disease frequency in human population" could not address the importance of genetic susceptibility of humans in disease occurrence. However, the use of biological or genetic markers identified and characterized by the help of advance in molecular biology and human genetics now can provide us better understanding of multi-factorial or multistep disease occurrence in humans. Biological markers used in molecular epidemiology are classified into three groups: biomarkers of exposure (i.e., carcinogen metabolites in human urine, DNA-adducts, etc.), biomarkers of effects (i.e., oncoproteins, tumor markers, etc.), and biomarkers of susceptibility (i.e., genetic polymorphisms of carcinogen metabolism enzymes, DNA repair, etc.). Susceptibility genes involved in disease pathogenesis are categorized into two groups: high penetrance genes (i.e., BRAC1, RB, etc.) and low penetrance genes (i.e., GSTs, XRCC1, etc.). This paper will address the usefulnesses of bomarkers in edpidemiologic research and will show the examples of the use of selected low penetrance genes involved in human carcinogenesis. The importance of multidisciplinary approaches among epidemiologists, molecular biologists, and human geneticists will also be discussed.

  18. Generation 2030/Africa

    ERIC Educational Resources Information Center

    You, Danzhen; Hug, Lucia; Anthony, David

    2014-01-01

    Until relatively recently, much of Africa has been among the economically least developed and least densely populated places on earth, replete with villages and rural communities. Africa is changing rapidly, in its economy, trade and investment; in climate change; in conflict and stability; in urbanization, migration patterns, and most of all in…

  19. Teaching about Francophone Africa.

    ERIC Educational Resources Information Center

    Merryfield, Mary; Timbo, Adama

    Lessons and resources for Social Studies and French courses are included in this document. The major goals of these materials are to help students (1) explore the history and geography of Francophone Africa, (2) examine French influences in contemporary Africa, (3) recognize and appreciate cultural differences and similarities in values and…

  20. Language in South Africa.

    ERIC Educational Resources Information Center

    Mesthrie, Rajend, Ed.

    This collection of 24 papers focuses on language and society in South Africa. Part 1, "The Main Language Groupings," includes (1) "South Africa: A Sociolinguistic Overview" (R. Mesthrie); (2) "The Khoesan Languages" (A. Traill); (3) "The Bantu Languages: Sociohistorical Perspectives" (Robert K. Herbert and Richard Bailey); (4) "Afrikaans:…

  1. Historical Capsule: South Africa.

    ERIC Educational Resources Information Center

    Cole, Robert

    1988-01-01

    Briefly traces the history of South Africa from British acquisition in 1815 through the creation of the Union of South Africa in 1910. Presents a chronicle of the year 1900 to show part of the European achievement in close-up. Lists accomplishments in literature, fine arts, science, technology, music, theater, and dance. (GEA)

  2. Multilingualism in Southern Africa.

    ERIC Educational Resources Information Center

    Peirce, Bonny Norton; Ridge, Stanley G. M.

    1997-01-01

    Reviews recent research in multilingualism in Southern Africa, focusing on the role of languages in education, sociolinguistics, and language policy. Much of the research is on South Africa. Topics discussed include language of instruction in schools, teacher education, higher education, adult literacy, language contact, gender and linguistic…

  3. Epidemiological study by pulsed-field gel electrophoresis of an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a geriatric hospital.

    PubMed Central

    Gouby, A; Neuwirth, C; Bourg, G; Bouziges, N; Carles-Nurit, M J; Despaux, E; Ramuz, M

    1994-01-01

    Twelve cases of infections caused by extended-spectrum beta-lactamase (ESBla)-producing Klebsiella pneumoniae were reported between August 1991 and March 1993 in the Geriatric Department of the Nimes University Hospital, where these bacterial had not been previously isolated. Restriction profiles of total genomic DNAs cleaved by XbaI and SpeI were compared by pulsed-field gel electrophoresis. The strains that were tested included the 12 isolates from K. pneumoniae-infected patients, strains recovered from rectal swabs of asymptomatic patients in the same ward, and strains isolated in other hospitals in Nîmes at the same time. The restriction profiles of the 12 isolates and those recovered from asymptomatic patients in the same ward were very similar. Over a period of more than 1 year, extended-spectrum beta-lactamases were not detected in K. pneumoniae isolates with restriction patterns different from that of the epidemic strain. It seems, therefore, that there was no transfer of a plasmid or a gene coding for ESBla to strains of K. pneumoniae that were different from the epidemic strain. At the same time, ESBla-producing K. pneumoniae isolates exhibiting restriction endonuclease profiles very different from that of the epidemic strain were isolated from other hospitals in Nîmes. None of these strains caused an outbreak. Pulsed-field gel electrophoresis, which allows precise characterization of strains beyond the species level, is a useful tool for studying the ESBla-producing K. pneumoniae strains involved in nosocomial outbreaks. Images PMID:8150938

  4. Study of the genetic heterogeneity of SAT-2 foot-and-mouth disease virus in sub-Saharan Africa with specific focus on East Africa.

    PubMed

    Sahle, M; Dwarka, R M; Venter, E H; Vosloo, W

    2007-12-01

    The epidemiology of serotype SAT-2 foot-and-mouth disease was investigated in sub-Saharan Africa by phylogenetic analysis using the 1D gene encoding the major antigenic determinant. Fourteen genotypes were identified of which three are novel and belong to East Africa, bringing the total number of genotypes for that region to eight. The genotypes clustered into three lineages that demonstrated surprising links between East, southern and south-western Africa. One lineage was unique to West Africa. These results established numerous incursions across country borders in East Africa and long term conservation of sequences for periods up to 41 years. Ethiopia, Kenya and Uganda have all experienced outbreaks from more than one unrelated strain, demonstrating the potential for new introductions. The amount of variation observed within this serotype nearly equalled that which was found between serotypes; this has severe implications for disease control using vaccination. PMID:18453238

  5. A New Arabia-Africa-Eurasia GPS Velocity Field (1994-2014) and E Mediterranean Block Model: Implications for Continental Deformation in a Zone of Active Plate Interaction

    NASA Astrophysics Data System (ADS)

    Vernant, P.; Floyd, M.; Ozener, H.; Ergintav, S.; Karakhanian, A.; Kadirov, F. A.; Sokhadze, G.; ArRajehi, A.; Nankali, H. R.; Georgiev, I.; Ganas, A.; Paradissis, D.; McClusky, S.; Gomez, F. G.; Reilinger, R. E.

    2014-12-01

    We present new GPS velocities for the Arabia-Africa-Eurasia region determined with GAMIT/GLOBK (>830 velocities) spanning the period 1994-2014. Here we consider the E Mediterranean region of plate interaction. We use DEFNODE software to develop block models and estimate slip rates on major faults and strain of some blocks. The wrms of residual velocities from our new model is 1.3 mm/yr. We identify small E-W extension within the newly defined Anatolian block confined to a 100-200 km wide zone south of the North Anatolian Fault (NAF) reaching 2-3 mm/yr with rates increasing towards the west. Possible causes we consider include, un-modeled postseismic effects of the 1999 Izmit/Duzce earthquake sequence, continuing post-seismic effects of the 20th Century sequence of M>7 earthquakes, and/or toroidal sub-lithospheric flow towards the subducting Hellenic slab. The overall strain rate of the Marmara Sea block is dominantly N-S extension, and the Van block, N-S compression. Present slip rates along the NAF increase from E to W, 22-24 mm/yr along the E to E-central segment and 27-28 mm/yr along the W segment. We quantify extension in the G. of Corinth, central Greece, and G. of Evia; the W, central and E sections of the Hellenic Trench are shortening with extension in the back-arc. The W Hellenic Trench and W Peloponnese have right-lateral strike-slip and the E Hellenic Trench, left-lateral ss. N-S extension (2-4 mm/yr) in N Greece and the N Aegean Sea extends at least to 42°N. Arabia-Sinai left-lateral motion across the Dead Sea Fault is ~5 mm/yr along the S segment; significant residual velocities along the N and S segments indicate lower slip rates in the N and require fault segmentation to account for slip rate variations along strike. We identify E-W contraction of the Arabian (Persian) Gulf (~3-5 mm/yr) that extends into the E part of the Arabian Plate. We will quantify and present these and other observed deformation patterns and discuss their tectonic implications.

  6. Multicentre studies of insecticide-treated durable wall lining in Africa and South-East Asia: entomological efficacy and household acceptability during one year of field use

    PubMed Central

    2012-01-01

    Background Indoor residual spraying (IRS) is a primary method of malaria vector control, but its potential impact is constrained by several inherent limitations: spraying must be repeated when insecticide residues decay, householders can tire of the annual imposition and campaign costs are recurrent. Durable lining (DL) can be considered an advanced form of long-lasting IRS where insecticide is gradually released from an aesthetically attractive wall lining material to provide vector control for several years. A multicentre trial was carried out in Equatorial Guinea, Ghana, Mali, South Africa and Vietnam to assess the feasibility, durability, bioefficacy and household acceptability of DL, compared to conventional IRS or insecticide-treated curtains (LLITCs), in a variety of operational settings. Methods This study was conducted in 220 households in traditional rural villages over 12-15 months. In all sites, rolls of DL were cut to fit house dimensions and fixed to interior wall surfaces (usually with nails and caps) by trained teams. Acceptability was assessed using a standardized questionnaire covering such topics as installation, exposure reactions, entomology, indoor environment, aesthetics and durability. Bioefficacy of interventions was evaluated using WHO cone bioassay tests at regular intervals throughout the year. Results The deltamethrin DL demonstrated little to no decline in bioefficacy over 12-15 months, supported by minimal loss of insecticide content. By contrast, IRS displayed a significant decrease in bioactivity by 6 months and full loss after 12 months. The majority of participants in DL households perceived reductions in mosquito density (93%) and biting (82%), but no changes in indoor temperature (83%). Among those households that wanted to retain the DL, 73% cited protective reasons, 20% expressed a desire to keep theirs for decoration and 7% valued both qualities equally. In Equatorial Guinea, when offered a choice of vector control product at

  7. Case-control studies of the effect of environmental sanitation on diarrhoea morbidity: methodological implications of field studies in Africa and Asia.

    PubMed

    Briscoe, J; Baltazar, J; Young, B

    1988-06-01

    The problems and prospects in the use of case-control studies to assess the effects of improvements in environmental sanitation on diarrhoea morbidity are discussed on the basis of two field studies. It is concluded that an adequate design is available for assessing the effects of a single improvement on diarrhoeal disease. The estimates of effect appear to be valid and sufficiently precise. For addressing more complex questions of interactions, sample sizes would have to be increased substantially. The experience with two field studies suggests that there is hope that a simpler protocol may be feasible, in which only limited information is collected, in which few home visits are made, and in which analytical techniques are simple. Until more field studies have been conducted definitive conclusions cannot be reached on the applicability of such a simple, rapid and inexpensive approach. PMID:3403140

  8. Recognizing Excellence in Maternal and Child Health (MCH) Epidemiology: The 2014 National MCH Epidemiology Awards

    PubMed Central

    Vladutiu, Catherine J.; Jones, Jessica R.

    2016-01-01

    Purpose The impact of programs, policies, and practices developed by professionals in the field of maternal and child health (MCH) epidemiology is highlighted biennially by 16 national MCH agencies and organizations, or the Coalition for Excellence in MCH Epidemiology. Description In September 2014, multiple leading agencies in the field of MCH partnered to host the national CityMatCH Leadership and MCH Epidemiology Conference in Phoenix, Arizona. The conference offered opportunities for peer exchange; presentation of new scientific methodologies, programs, and policies; dialogue on changes in the MCH field; and discussion of emerging MCH issues relevant to the work of local, state, and national MCH professionals. During the conference, the National MCH Epidemiology Awards were presented to individuals, teams, institutions, and leaders for significantly contributing to the improved health of women, children, and families. Assessment During the conference, the Coalition presented seven deserving health researchers and research groups with national awards in the areas of advancing knowledge, effective practice, outstanding leadership, young professional achievement, and lifetime achievement. The article highlights the accomplishments of these national-level awardees. Conclusion Recognition of deserving professionals strengthens the field of MCH epidemiology, and sets the standard for exceptional research, mentoring, and practice. PMID:26723200

  9. How mathematical epidemiology became a field of biology: a commentary on Anderson and May (1981) ‘The population dynamics of microparasites and their invertebrate hosts’

    PubMed Central

    Heesterbeek, J. A. P.; Roberts, M. G.

    2015-01-01

    We discuss the context, content and importance of the paper ‘The population dynamics of microparasites and their invertebrate hosts’, by R. M. Anderson and R. M. May, published in the Philosophical Transactions of the Royal Society as a stand-alone issue in 1981. We do this from the broader perspective of the study of infectious disease dynamics, rather than the specific perspective of the dynamics of insect pathogens. We argue that their 1981 paper fits seamlessly in the systematic study of infectious disease dynamics that was initiated by the authors in 1978, combining effective use of simple mathematical models, firmly rooted in biology, with observable or empirically measurable ingredients and quantities, and promoting extensive capacity building. This systematic approach, taking ecology and biology rather than applied mathematics as the motivation for advance, proved essential for the maturation of the field, and culminated in their landmark textbook of 1991. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750231

  10. Epidemiology and the scientific method.

    PubMed

    Chalmers, A F

    1982-01-01

    This article refutes the claim that the field of epidemiology and community health would benefit from the application of the scientific method. It is argued that the methods of physics are not appropriate for other disciplines. When applied to the social sciences, positivism is a conservatizing force, causing theory to become based on a mere description of social phenomenon. Since it cannot lead to a deep understanding of social phenomena, positivism is incapable of revealing ways in which society could be radically changed. Moreover, such theory is far from neutral. Rather, it is formed and influenced by the forms of life experienced and practiced in the society. This is illustrated by an analysis of the origin of modern physics at the time when society was changing from a feudal to capitalist form of organization. It is concluded that advances will be made in epidemiology and community health when this field breaks from its focus on the individual and incorporates class into its analysis. However, given the interconnection between social structure and social theory, resistance to such a radical change can be expected. PMID:7141777

  11. Safe water for Africa (Africa-1000)

    SciTech Connect

    Dalton, R.; Kashkari, C.

    1996-12-31

    Africa-1000 is a program to provide safe water to thousands of villages in Africa. It is a formidable effort and needs the support of the international scientific community. Science and technology is the only hope for a solution of the African crisis. There are vast areas in the Sub-Saharan Africa that have water under the ground but due to lack of electric power, the water cannot be pumped. Thus the land is dry and barren and people are starving. The African continent has abundant renewable energy in the form of solar and wind energy. The technologies are well developed and available in the developed countries. Therefore, the solution is as follows: dig and drill wells and boreholes to reach underground water; install standardized solar or wind driven pumps to bring water to the surface; train village technicians to operate, maintain and repair these energy systems; and replicate these installations in thousands of villages, thus establishing standard water and energy systems across Africa.

  12. Characterization of epidemiologically unrelated Acinetobacter baumannii isolates from four continents by use of multilocus sequence typing, pulsed-field gel electrophoresis, and sequence-based typing of bla(OXA-51-like) genes.

    PubMed

    Hamouda, Ahmed; Evans, Benjamin A; Towner, Kevin J; Amyes, Sebastian G B

    2010-07-01

    This study used a diverse collection of epidemiologically unrelated Acinetobacter baumannii isolates to compare the robustness of a multilocus sequence typing (MLST) scheme, based on conserved regions of seven housekeeping genes, gltA, gdhB, recA, cpn60, rpoD, gyrB, and gpi, with that of sequence-based typing of bla(OXA-51-like) genes (SBT-bla(OXA-51-like) genes). The data obtained by analysis of MLST and SBT-bla(OXA-51-like) genes were compared to the data generated by pulsed-field gel electrophoresis (PFGE). The topologies of the phylogenetic trees generated for the gyrB and gpi genes showed evidence of recombination and were inconsistent with those of the trees generated for the other five genes. MLST identified 24 sequence types (STs), of which 19 were novel, and 5 novel alleles. Clonality was demonstrated by eBURST analysis and standardized index of association values of >1 (P < 0.001). MLST data revealed that all isolates harboring the major bla(OXA-51-like) alleles OXA-66, OXA-69, and OXA-71 fell within the three major European clonal lineages. However, the MLST data were not always in concordance with the PFGE data, and some isolates containing the same bla(OXA-51-like) allele demonstrated <50% relatedness by PFGE. It was concluded that the gyrB and gpi genes are not good candidates for use in MLST analysis and that a SBT-bla(OXA-51-like) gene scheme produced results comparable to those produced by MLST for the identification of the major epidemic lineages, with the advantage of having a significantly reduced sequencing cost and time. It is proposed that studies of A. baumannii epidemiology could involve initial screening of bla(OXA-51-like) alleles to identify isolates belonging to major epidemic lineages, followed by MLST analysis to categorize isolates from common lineages, with PFGE being reserved for fine-scale typing. PMID:20421437

  13. Volcanism in Eastern Africa

    NASA Technical Reports Server (NTRS)

    Cauthen, Clay; Coombs, Cassandra R.

    1996-01-01

    In 1891, the Virunga Mountains of Eastern Zaire were first acknowledged as volcanoes, and since then, the Virunga Mountain chain has demonstrated its potentially violent volcanic nature. The Virunga Mountains lie across the Eastern African Rift in an E-W direction located north of Lake Kivu. Mt. Nyamuragira and Mt. Nyiragongo present the most hazard of the eight mountains making up Virunga volcanic field, with the most recent activity during the 1970-90's. In 1977, after almost eighty years of moderate activity and periods of quiescence, Mt. Nyamuragira became highly active with lava flows that extruded from fissures on flanks circumscribing the volcano. The flows destroyed vast areas of vegetation and Zairian National Park areas, but no casualties were reported. Mt. Nyiragongo exhibited the same type volcanic activity, in association with regional tectonics that effected Mt. Nyamuragira, with variations of lava lake levels, lava fountains, and lava flows that resided in Lake Kivu. Mt. Nyiragongo, recently named a Decade volcano, presents both a direct and an indirect hazard to the inhabitants and properties located near the volcano. The Virunga volcanoes pose four major threats: volcanic eruptions, lava flows, toxic gas emission (CH4 and CO2), and earthquakes. Thus, the volcanoes of the Eastern African volcanic field emanate harm to the surrounding area by the forecast of volcanic eruptions. During the JSC Summer Fellowship program, we will acquire and collate remote sensing, photographic (Space Shuttle images), topographic and field data. In addition, maps of the extent and morphology(ies) of the features will be constructed using digital image information. The database generated will serve to create a Geographic Information System for easy access of information of the Eastem African volcanic field. The analysis of volcanism in Eastern Africa will permit a comparison for those areas from which we have field data. Results from this summer's work will permit

  14. Problem of hepatocellular carcinoma in West Africa

    PubMed Central

    Ladep, Nimzing G; Lesi, Olufunmilayo A; Mark, Pantong; Lemoine, Maud; Onyekwere, Charles; Afihene, Mary; Crossey, Mary ME; Taylor-Robinson, Simon D

    2014-01-01

    The incidence of hepatocellular carcinoma (HCC) is known to be high in West Africa with an approximate yearly mortality rate of 200000. Several factors are responsible for this. Early acquisition of risk factors; with vertical or horizontal transmission of hepatitis B (HBV), environmental food contaminants (aflatoxins), poor management of predisposing risk factors and poorly-managed strategies for health delivery. There has been a low uptake of childhood immunisation for hepatitis B in many West African countries. Owing to late presentations, most sufferers of HCC die within weeks of their diagnosis. Highlighted reasons for the specific disease pattern of HCC in West Africa include: (1) high rate of risk factors; (2) failure to identify at risk populations; (3) lack of effective treatment; and (4) scarce resources for timely diagnosis. This is contrasted to the developed world, which generally has sufficient resources to detect cases early for curative treatment. Provision of palliative care for HCC patients is limited by availability and affordability of potent analgesics. Regional efforts, as well as collaborative networking activities hold promise that could change the epidemiology of HCC in West Africa. PMID:25429316

  15. History of Sleeping Sickness in East Africa

    PubMed Central

    Hide, Geoff

    1999-01-01

    The history of human sleeping sickness in East Africa is characterized by the appearance of disease epidemics interspersed by long periods of endemicity. Despite the presence of the tsetse fly in large areas of East Africa, these epidemics tend to occur multiply in specific regions or foci rather than spreading over vast areas. Many theories have been proposed to explain this phenomenon, but recent molecular approaches and detailed analyses of epidemics have highlighted the stability of human-infective trypanosome strains within these foci. The new molecular data, taken alongside the history and biology of human sleeping sickness, are beginning to highlight the important factors involved in the generation of epidemics. Specific, human-infective trypanosome strains may be associated with each focus, which, in the presence of the right conditions, can be responsible for the generation of an epidemic. Changes in agricultural practice, favoring the presence of tsetse flies, and the important contribution of domestic animals as a reservoir for the parasite are key factors in the maintenance of such epidemics. This review examines the contribution of molecular and genetic data to our understanding of the epidemiology and history of human sleeping sickness in East Africa. PMID:9880477

  16. Development of microbiological field methodology for water and food-chain hygiene analysis of Campylobacter spp. and Yersinia spp. in Burkina Faso, West Africa.

    PubMed

    Hakalehto, Elias; Nyholm, Outi; Bonkoungou, Isidore J O; Kagambega, Assèta; Rissanen, Kari; Heitto, Anneli; Barro, Nicolas; Haukka, Kaisa

    2014-09-01

    Field-adaptable research methods for identifying Campylobacter sp., Yersinia sp. and other pathogenic and indicator bacteria were designed in Finland and tested in Burkina Faso. Several bacterial groups were also validated from artificially contaminated samples. Campylobacter strains were cultivated using an innovative gas generation system: The 'Portable Microbe Enrichment Unit' (PMEU) which provides microaerobic gas flow into the enrichment broth. This enhanced cultivation system produced rapid growth of several isolates of campylobacteria from water and chicken samples. The latter were obtained from local marketplace samples. No yersinias were found in the field studies, whereas they were readily recovered from the spiked samples, as well as Salmonella sp. and Escherichia coli strains. The PMEU method turned out to be reliable for monitoring of water and food hygiene in remote locations. PMID:25156815

  17. Poverty reduction in Africa

    PubMed Central

    Collier, Paul

    2007-01-01

    Poverty in Africa has been rising for the last quarter-century, while it has been falling in the rest of the developing world. Africa's distinctive problem is that its economies have not been growing. This article attempts to synthesize a range of recent research to account for this failure of the growth process. I argue that the reasons lie not in African peculiarities but rather in geographic features that globally cause problems but that are disproportionately pronounced in Africa. These features interact to create three distinct challenges that are likely to require international interventions beyond the conventional reliance on aid. PMID:17942702

  18. Sickle Cell Disease: New Opportunities and Challenges in Africa

    PubMed Central

    Makani, J.; Ofori-Acquah, S. F.; Nnodu, O.; Wonkam, A.; Ohene-Frempong, K.

    2013-01-01

    Sickle cell disease (SCD) is one of the most common genetic causes of illness and death in the world. This is a review of SCD in Africa, which bears the highest burden of disease. The first section provides an introduction to the molecular basis of SCD and the pathophysiological mechanism of selected clinical events. The second section discusses the epidemiology of the disease (prevalence, morbidity, and mortality), at global level and within Africa. The third section discusses the laboratory diagnosis and management of SCD, emphasizing strategies that been have proven to be effective in areas with limited resources. Throughout the review, specific activities that require evidence to guide healthcare in Africa, as well as strategic areas for further research, will be highlighted. PMID:25143960

  19. Second assessment of NeuroAIDS in Africa

    PubMed Central

    Robertson, Kevin; Kopnisky, Kathy; Hakim, James; Merry, Concepta; Nakasujja, Noeline; Hall, Colin; Traore, Moussa; Sacktor, Ned; Clifford, David; Newton, Charles; Van Rie, Annelies; Holding, Penny; Clements, Janice; Zink, Christine; Mielke, Jens; Hosseinipour, Mina; Lalloo, Umesh; Amod, Farida; Marra, Christina; Evans, Scott; Liner, Jeff

    2009-01-01

    In July of 2006, the National Institute of Mental Health (NIMH) Center for Mental Health Research on AIDS (CMHRA) sponsored the second conference on the Assessment of NeuroAIDS in Africa, which was held in Arusha, Tanzania. The conference mission was to address the regional variations in epidemiology of HIV-related neurological disorders as well as the assessment and diagnosis of these disorders. Participants discussed and presented data regarding the relevance and translation of neuroAIDS assessment measures developed in resource intensive settings and the challenges of neuro-assessment in Africa, including the applicability of current tools, higher prevalence of confounding diseases, and the complexity of diverse cultural settings. The conference presentations summarized here highlight the need for further research on neuroAIDS in Africa and methods for assessing HIV-related neurological disorders. PMID:18370346

  20. Shifting epidemiology of Flaviviridae.

    PubMed

    Petersen, Lyle R; Marfin, Anthony A

    2005-04-01

    The dengue, West Nile, Japanese encephalitis and yellow fever viruses are important mosquito-borne viruses whose epidemiology is shifting in response to changing societal factors, such as increasing commerce, urbanization of rural areas, and population growth. All four viruses are expanding geographically, as exemplified by the emergence of West Nile virus in the Americas and Japanese encephalitis virus in Australasia. The large, recent global outbreaks of severe neurological disease caused by West Nile virus, the increasing frequency of dengue hemorrhagic fever outbreaks in the Americas, and the emergence of yellow fever virus vaccination-associated viscerotropic disease, are new clinical epidemiologic trends. These worrisome epidemiologic trends will probably continue in coming decades, as a reversal of their societal and biological drivers is not in sight. Nevertheless, the substantial reductions in Japanese encephalitis virus incidence resulting from vaccination programs and economic development in some Asian countries provide some encouragement within this overall guarded outlook.

  1. Whose epidemiology, whose health?

    PubMed

    Wing, S

    1998-01-01

    Simplistic claims about the objectivity of science have been challenged from a variety of perspectives. Evaluation of the external context of production of knowledge and the methodological approaches to posing questions and assembling evidence shows that there is no pure "science"; rather, all scientific knowledge is shaped by the social history of its production. Examples are given of how quantitative concepts in modern epidemiology influence the recognition of the causes of disease. The author uses the phenomenon of intensive swine production by vertically integrated agribusiness to illustrate how broad problems such as environmental racism, agricultural determinants of nutrition, loss of natural resources, and conditions conducive to emergence of new diseases are hidden by epidemiological approaches that fit into corporate policy perspectives. It is critically important to ask who produces epidemiological knowledge, and whose health is promoted by that knowledge.

  2. An argument for a consequentialist epidemiology.

    PubMed

    Galea, Sandro

    2013-10-15

    Epidemiology is the study of the causes and distributions of diseases in human populations so that we may identify ways to prevent and control disease. Although this definition broadly serves us well, I suggest that in recent decades, our discipline's robust interest in identifying causes has come at the expense of a more rigorous engagement with the second part of our vision for ourselves-the intent for us to intervene-and that this approach threatens to diminish our field's relevance. I argue here for a consequentialist epidemiology, a formalization and recalibration of the philosophical foundations of our discipline. I discuss how epidemiology is, at its core, more comfortably a consequentialist, as opposed to a deontological, discipline. A more consequentialist approach to epidemiology has several implications. It clarifies our research priorities, offers a perspective on the place of novel epidemiologic approaches and a metric to evaluate the utility of new methods, elevates the importance of global health and considerations about equity to the discipline, brings into sharp focus our engagement in implementation and translational science, and has implications for how we teach our students. I intend this article to be a provocation that can help clarify our disciplinary intentions. PMID:24022890

  3. Epidemiology of Lung Cancer.

    PubMed

    Mao, Yousheng; Yang, Ding; He, Jie; Krasna, Mark J

    2016-07-01

    Lung cancer has been transformed from a rare disease into a global problem and public health issue. The etiologic factors of lung cancer become more complex along with industrialization, urbanization, and environmental pollution around the world. Currently, the control of lung cancer has attracted worldwide attention. Studies on the epidemiologic characteristics of lung cancer and its relative risk factors have played an important role in the tertiary prevention of lung cancer and in exploring new ways of diagnosis and treatment. This article reviews the current evolution of the epidemiology of lung cancer. PMID:27261907

  4. Research Management in Africa.

    ERIC Educational Resources Information Center

    Benneh, George

    2002-01-01

    Examines research management, particularly within higher education institutions, in Africa including, research and current trends in knowledge production, institutional aspects, research funding, and good practice in research management. (EV)

  5. Women in Africa

    ERIC Educational Resources Information Center

    Spitzer, Manon

    1975-01-01

    The role and status of women in Africa has changed profoundly since the end of the colonial period. Many differences in women's status and role are based on geography, history, nationality, political and socioeconomic systems, culture, and religion. (JR)

  6. Mathematical models of human african trypanosomiasis epidemiology.

    PubMed

    Rock, Kat S; Stone, Chris M; Hastings, Ian M; Keeling, Matt J; Torr, Steve J; Chitnis, Nakul

    2015-03-01

    Human African trypanosomiasis (HAT), commonly called sleeping sickness, is caused by Trypanosoma spp. and transmitted by tsetse flies (Glossina spp.). HAT is usually fatal if untreated and transmission occurs in foci across sub-Saharan Africa. Mathematical modelling of HAT began in the 1980s with extensions of the Ross-Macdonald malaria model and has since consisted, with a few exceptions, of similar deterministic compartmental models. These models have captured the main features of HAT epidemiology and provided insight on the effectiveness of the two main control interventions (treatment of humans and tsetse fly control) in eliminating transmission. However, most existing models have overestimated prevalence of infection and ignored transient dynamics. There is a need for properly validated models, evolving with improved data collection, that can provide quantitative predictions to help guide control and elimination strategies for HAT.

  7. Profile of South Africa

    SciTech Connect

    Fox, G.J.; Tonneson, L.C.

    1996-08-01

    A broad overview of the Republic of South Africa`s nuclear energy program is presented. Economic aspects are the main focus of the article, and numerical data is provided for electricity generation and use and uranium production. The role of the molecular laser isotope process for enrichment is discussed. The research reactor program, waste disposal and decommissioning, mining history, uranium production, and nonproliferation policy are other highlighted topics.

  8. Astronomy Landscape in Africa

    NASA Astrophysics Data System (ADS)

    Nemaungani, Takalani

    2015-01-01

    The vision for astronomy in Africa is embedded in the African Space Policy of the African Union in early 2014. The vision is about positioning Africa as an emerging hub for astronomy sciences and facilities. Africa recognized the need to take advantage of its natural resource, the geographical advantage of the clear southern skies and pristine sites for astronomy. The Pan African University (PAU) initiative also presents an opportunity as a post-graduate training and research network of university nodes in five regions of Africa and supported by the African Union. The Southern African node based in South Africa concentrates on space sciences which also includes astronomy. The PAU aims to provide the opportunity for advanced graduate training and postgraduate research to high-performing African students. Objectives also include promoting mobility of students and teachers and harmonizing programs and degrees.A number of astronomy initiatives have burgeoned in the Southern African region and these include the Southern Africa Largest Optical Telescope (SALT), HESS (High Energy Stereoscopic System), the SKA (Square Kilometre Array) and the AVN (African Very Long Baseline Interferometer Network). There is a growing appetite for astronomy sciences in Africa. In East Africa, the astronomy community is well organized and is growing - the East African Astronomical society (EAAS) held its successful fourth annual conference since 2010 on 30 June to 04 July 2014 at the University of Rwanda. Centred around the 'Role of Astronomy in Socio-Economic Transformation,' this conference aimed at strengthening capacity building in Astronomy, Astrophysics and Space Science in general, while providing a forum for astronomers from the region to train young and upcoming scientists.

  9. Evolution of the Malvinas Plate South of Africa

    NASA Astrophysics Data System (ADS)

    Marks, K. M.; Stock, J. M.

    2001-07-01

    We confirm that a Malvinas Plate is required in the Agulhas Basin during the Late Cretaceous because: (1) oblique Mercator plots of marine gravity show that fracture zones generated on the Agulhas rift, as well as the Agulhas Fracture Zone, do not lie on small circles about the 33o-28y South America-Africa stage pole and were therefore not formed by South America-Africa spreading, (2) the 33o-28y South America-Africa stage rotation does not bring 33o magnetic anomalies on the Malvinas Plate into alignment with their conjugates on the African Plate, and (3) errors in the 33o-28y South America-Africa stage rotation cannot account for the misalignment. We present improved Malvinas-Africa finite rotations determined by interpreting magnetic anomaly data in light of fracture zones and extinct spreading rift segments (the Agulhas rift) that are clearly revealed in satellite-derived marine gravity fields covering the Agulhas Basin. The tectonic history of the Malvinas Plate is chronicled through gravity field reconstructions that use the improved Malvinas-Africa finite rotations and more recent South America-Africa and Antarctica-Africa finite rotations. Newly-mapped triple junction traces on the Antarctic, South American, Malvinas, and African Plates, combined with geometric and magnetic constraints observed in the reconstructions, enable us to investigate the locations of the elusive western and southern boundaries of the Malvinas Plate.

  10. Usutu virus in Africa.

    PubMed

    Nikolay, Birgit; Diallo, Mawlouth; Boye, Cheikh Saad Bouh; Sall, Amadou Alpha

    2011-11-01

    Usutu virus (USUV) was discovered in South Africa in 1959. Since then, it has been reported in several African countries including Senegal, Central African Republic, Nigeria, Uganda, Burkina Faso, Cote d'Ivoire, and Morocco. In 2001, USUV has been identified for the first time outside of Africa, namely in Europe, where it caused a significant mortality among blackbirds in Vienna, Austria. In 2009, the first two human cases of USUV infection in Europe have been reported in Italy, causing encephalitis in immunocompromised patients. The host range in Africa includes mainly Culex mosquitoes, birds, and also humans with one benign and one severe case. Given its role as a potential human pathogen and the similar appearance compared with other emerging arboviruses, it is essential to investigate the natural history and ecology of USUV in Africa. In this regard, we review the emergence of USUV in Africa, summarizing data about isolations, host range, and potential vectors, which should help to improve our understanding of the factors underlying the circulation of USUV in Europe and Africa. PMID:21767160

  11. Evolutionary analysis of foot-and-mouth disease virus serotype SAT 1 isolates from east africa suggests two independent introductions from southern africa

    PubMed Central

    2010-01-01

    Background In East Africa, foot-and-mouth disease virus serotype SAT 1 is responsible for occasional severe outbreaks in livestock and is known to be maintained within the buffalo populations. Little is known about the evolutionary forces underlying its epidemiology in the region. To enhance our appreciation of the epidemiological status of serotype SAT 1 virus in the region, we inferred its evolutionary and phylogeographic history by means of genealogy-based coalescent methods using 53 VP1 coding sequences covering a sampling period from 1948-2007. Results The VP1 coding sequence of 11 serotype SAT 1 FMD viruses from East Africa has been determined and compared with known sequences derived from other SAT 1 viruses from sub-Saharan Africa. Purifying (negative) selection and low substitution rates characterized the SAT 1 virus isolates in East Africa. Two virus groups with probable independent introductions from southern Africa were identified from a maximum clade credibility tree. One group was exclusive to Uganda while the other was present within Kenya and Tanzania. Conclusions Our results provide a baseline characterization of the inter-regional spread of SAT 1 in sub-Saharan Africa and highlight the importance of a regional approach to trans-boundary animal disease control in order to monitor circulating strains and apply appropriate vaccines. PMID:21118525

  12. Molecular Epidemiology of Malaria

    PubMed Central

    Conway, David J.

    2007-01-01

    Malaria persists as an undiminished global problem, but the resources available to address it have increased. Many tools for understanding its biology and epidemiology are well developed, with a particular richness of comparative genome sequences. Targeted genetic manipulation is now effectively combined with in vitro culture assays on the most important human parasite, Plasmodium falciparum, and with in vivo analysis of rodent and monkey malaria parasites in their laboratory hosts. Studies of the epidemiology, prevention, and treatment of human malaria have already been influenced by the availability of molecular methods, and analyses of parasite polymorphisms have long had useful and highly informative applications. However, the molecular epidemiology of malaria is currently undergoing its most substantial revolution as a result of the genomic information and technologies that are available in well-resourced centers. It is a challenge for research agendas to face the real needs presented by a disease that largely exists in extremely resource-poor settings, but it is one that there appears to be an increased willingness to undertake. To this end, developments in the molecular epidemiology of malaria are reviewed here, emphasizing aspects that may be current and future priorities. PMID:17223628

  13. Phylogenetically resolving epidemiologic linkage

    DOE PAGES

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-02-22

    The use of phylogenetic trees in epidemiological investigations has become commonplace, but their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the truemore » transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. Moreover, we confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results.« less

  14. Causality in epidemiology.

    PubMed

    Kamangar, Farin

    2012-10-01

    This article provides an introduction to the meaning of causality in epidemiology and methods that epidemiologists use to distinguish causal associations from non-causal ones. Alternatives to causal association are discussed in detail. Hill's guidelines, set forth approximately 50 years ago, and more recent developments are reviewed. The role of religious and philosophic views in our understanding of causality is briefly discussed.

  15. Epidemiology of Down Syndrome

    ERIC Educational Resources Information Center

    Sherman, Stephanie L.; Allen, Emily G.; Bean, Lora H.; Freeman, Sallie B.

    2007-01-01

    Down syndrome (DS) is the most commonly identified genetic form of mental retardation and the leading cause of specific birth defects and medical conditions. Traditional epidemiological studies to determine the prevalence, cause, and clinical significance of the syndrome have been conducted over the last 100 years. DS has been estimated to occur…

  16. Phylogenetically resolving epidemiologic linkage.

    PubMed

    Romero-Severson, Ethan O; Bulla, Ingo; Leitner, Thomas

    2016-03-01

    Although the use of phylogenetic trees in epidemiological investigations has become commonplace, their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the true transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals' HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. We confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results. PMID:26903617

  17. Phylogenetically resolving epidemiologic linkage

    PubMed Central

    Romero-Severson, Ethan O.; Bulla, Ingo; Leitner, Thomas

    2016-01-01

    Although the use of phylogenetic trees in epidemiological investigations has become commonplace, their epidemiological interpretation has not been systematically evaluated. Here, we use an HIV-1 within-host coalescent model to probabilistically evaluate transmission histories of two epidemiologically linked hosts. Previous critique of phylogenetic reconstruction has claimed that direction of transmission is difficult to infer, and that the existence of unsampled intermediary links or common sources can never be excluded. The phylogenetic relationship between the HIV populations of epidemiologically linked hosts can be classified into six types of trees, based on cladistic relationships and whether the reconstruction is consistent with the true transmission history or not. We show that the direction of transmission and whether unsampled intermediary links or common sources existed make very different predictions about expected phylogenetic relationships: (i) Direction of transmission can often be established when paraphyly exists, (ii) intermediary links can be excluded when multiple lineages were transmitted, and (iii) when the sampled individuals’ HIV populations both are monophyletic a common source was likely the origin. Inconsistent results, suggesting the wrong transmission direction, were generally rare. In addition, the expected tree topology also depends on the number of transmitted lineages, the sample size, the time of the sample relative to transmission, and how fast the diversity increases after infection. Typically, 20 or more sequences per subject give robust results. We confirm our theoretical evaluations with analyses of real transmission histories and discuss how our findings should aid in interpreting phylogenetic results. PMID:26903617

  18. [Toxoplasmosis: Epidemiology, Diagnosis, Treatment].

    PubMed

    Khryanin, A A; Reshetnikov, O V; Kuvshinova, I N

    2015-01-01

    The up-to-date literature and original data on the epidemiology, diagnosis and treatment of toxoplasmosis are presented. Particular attention is paid to the parasite infection during pregnancy. Spiramycin is the drug of choice for acute toxoplasmosis in pregnant women.

  19. Epidemiology of Cardiovascular Diseases.

    ERIC Educational Resources Information Center

    Jenkins, C. David

    1988-01-01

    Reviews epidemiological studies of cardiovascular diseases especially coronary heart disease (CHD), to document their major public health importance, changes in mortality during this century, and international comparisons of trends. Finds major risk factors for CHD are determined in large part by psychosocial and behavioral mechanisms. Asserts…

  20. Epidemiology and pathogenicity of African bat lyssaviruses.

    PubMed

    Markotter, W; Van Eeden, C; Kuzmin, I V; Rupprecht, C E; Paweska, J T; Swanepoel, R; Fooks, A R; Sabeta, C T; Cliquet, F; Nel, L H

    2008-01-01

    Lyssaviruses belonging to all four known African Lyssavirus genotypes (gts) have been reported and isolated from SouthAfrica over the past few decades. These are: (1) Duvenhage virus (gt4), isolated again in 2006 from a human fatality; (2) Mokola virus (gt3), isolated irregularly, mostly from cats; (3) Lagos bat virus (gt2) continually isolated over the past four years from Epomophorus fruit bats and from incidental terrestrial animals and (4) Rabies virus (gt1) - with two virus biotypes endemic in mongoose and in canid species (mostly domestic dogs, jackals and bat-eared foxes), respectively. Only two of these are associated with bats in Southern Africa, viz. Duvenhage virus and Lagos bat virus (gts 4 and 2). For both these genotypes the authors have embarked on a programme of comparative study of molecular epidemiology. Duvenhage virus nucleoprotein nucleotide sequence analysis indicated a very low nucleotide diversity even though isolates were isolated decades apart. In contrast, individual isolates of Lagos bat virus were found to differ significantly with respectto nucleoprotein gene nucleotide sequence diversity as well as in pathogenicity profiles. PMID:18634494

  1. Molecular epidemiology of canine parvovirus in Morocco.

    PubMed

    Amrani, Nadia; Desario, Costantina; Kadiri, Ahlam; Cavalli, Alessandra; Berrada, Jaouad; Zro, Khalil; Sebbar, Ghizlane; Colaianni, Maria Loredana; Parisi, Antonio; Elia, Gabriella; Buonavoglia, Canio; Malik, Jamal; Decaro, Nicola

    2016-07-01

    Since it first emergence in the mid-1970's, canine parvovirus 2 (CPV-2) has evolved giving rise to new antigenic variants termed CPV-2a, CPV-2b and CPV-2c, which have completely replaced the original strain and had been variously distributed worldwide. In Africa limited data are available on epidemiological prevalence of these new types. Hence, the aim of the present study was to determine circulating variants in Morocco. Through TaqMan-based real-time PCR assay, 91 samples, collected from symptomatic dogs originating from various cities between 2011 and 2015, were diagnosed. Positive specimens were characterised by means of minor groove binder (MGB) probe PCR. The results showed that all samples but one (98.9%) were CPV positive, of which 1 (1.1%) was characterised as CPV-2a, 43 (47.7%) as CPV-2b and 39 (43.3%) as CPV-2c. Interestingly, a co-infection with CPV-2b and CPV-2c was detected in 4 (4.4%) samples and 3 (3.3%) samples were not characterised. Sequencing of the full VP2 gene revealed these 3 uncharacterised strains as CPV-2c, displaying a change G4068A responsible for the replacement of aspartic acid with asparagine at residue 427, impacting the MGB probe binding. In this work we provide a better understanding of the current status of prevailing CPV strains in northern Africa.

  2. Field and in vitro insecticidal efficacy of alphacypermethrin-treated high density polyethylene mesh against Culicoides biting midges in South Africa.

    PubMed

    Page, P C; Labuschagne, K; Venter, G J; Schoeman, J P; Guthrie, A J

    2014-06-16

    The efficacy of untreated and alphacypermethrin-treated high density polyethylene (HDPE) mesh against Culicoides biting midges (Diptera: Ceratopogonidae) was determined using Onderstepoort downdraught black light traps and a contact bioassay. Three traps were operated overnight in four replicates of a 3×3 randomised Latin square design near horses under South African field conditions. Both the untreated and alphacypermethrin-treated HDPE mesh significantly (P<0.05) reduced the numbers of Culicoides midges, predominantly Culicoides (Avaritia) imicola Kieffer, collected in the light traps by 4.2 and 7.2 times, respectively. A repellent effect of the alphacypermethrin-treated mesh was not confirmed because the number of midges collected in the light traps with untreated and alphacypermethrin-treated HDPE mesh was not significantly different (P=0.656). Bioassay of the insecticidal contact efficacy indicated median C. imicola mortality of 100% from 30 and 10 min following exposure to the alphacypermethrin-treated HDPE mesh for 1 or 3 min, respectively. In the bioassay, mortality was significantly higher (P=0.016) at 5 min post exposure in the midges exposed to the alphacypermethrin-treated mesh for 3 min (74.8%) compared to the 1 min exposure group (59.5%). The HDPE mesh could be used to reduce exposure of housed animals to Culicoides midges, specifically C. imicola, and viruses transmitted by these midges. Mesh treated with alphacypermethrin had the additional benefit of a rapid insecticidal effect on C. imicola. PMID:24655725

  3. Unravelling regolith material types using Mg/Al and K/Al plot to support field regolith identification in the savannah regions of NW Ghana, West Africa

    NASA Astrophysics Data System (ADS)

    Arhin, Emmanuel; Zango, Saeed M.

    2015-12-01

    The XRF analytical method was used to measure the weight % of the major oxides in regolith samples. The metal weight % of Mg, K and Al were calculated from their oxides and were normalised relative to immobile Al calculated from its oxide. The plot of Mg/Al and K/Al identified the regolith of the study area to consist of 137 transported clays, 4 ferruginous sediments or ferricrete, 2 lateritic duricrust and 4 saprolites. Surface regolith that had undergone secondary transformation and shows compositional overlaps were 4 transported clays with Fe-oxide impregnation may be referred to as nodular laterite and 5 ferruginous saprolites. The variable regolith materials features identified from the 154 samples enabled the characterisation and identification of the different sample materials because an overprint of bedrock geochemistry is reflected in the regolith. Plot of Mg/Al and K/Al highlighted the compositional variability of the regolith samples and refute the notion of the homogeneity of all the sampled materials in the area. The study thus recognized Mg/Al versus K/Al plots to be used in supporting field identification of regolith mapping units particularly in complex regolith terrains of savannah regions of Ghana and in similar areas where geochemical exploration surveys are being carried out under cover.

  4. Central and southern Africa

    SciTech Connect

    McGrew, H.J.

    1981-10-01

    Exploration in central and southern Africa continued to expand during 1980. The greatest concentration of activity was in Nigeria. However, there was considerable increase in the level of exploratory work in Cameroon and Congo. Significant new finds have been made in Ivory Coast. Geological and geophysical activity was carried out in 18 of the countries, with those in the western part having the largest share. Seismic work involved 225 party months of operation. Most of this time was spent on land, but marine operations accounted for 73,389 km of new control. Gravity and magnetic data were recorded during the marine surveys, and several large aeromagnetic projects were undertaken to obtain a total of 164,498 line km of data. Exploratory and development drilling accounted for a total of 304 wells and 2,605,044 ft (794,212 m) of hole. The 92 exploratory wells that were drilled resulted in 47 oil and gas discoveries. In development drilling 89% of the 212 wells were successful. At the end of the year, 27 exploratory wells were underway, and 34 development wells were being drilled for a total of 61. Oil production from the countries that this review covers was 918,747,009 bbl in 1980, a drop of about 9% from the previous year. Countries showing a decline in production were Nigeria, Gabon, Cabinda, and Zaire. Increases were recorded in Cameroon, Congo, and Ghana. A new country was added to the list of producers when production from the Belier field in Ivory Coast came on stream. 33 figures, 15 tables.

  5. [Future prospects of molecular epidemiology in tuberculosis].

    PubMed

    Matsumoto, Tomoshige; Iwamoto, Tomotada

    2009-12-01

    easily compare the genotypic data of independent studies between different laboratories. With the advantages, VNTR surpassed IS6110 RFLP and became the first line genotyping method in molecular epidemiology. One of the most attractive potentials on this method is its applicability for establishment of the database of M. tuberculosis genotype which covers not only local area but also world wide scale. This would open the door to "in silico epidemiology" which brings a breakthrough on the current TB control program. The optimization and standardization of the combination of VNTR loci for strain genotyping is the only but hard issue for the development of global database system. Road to the global Mtb genotype database is hard, but we believe, "Yes, We Can!". Another attractive potential of VNTR is its use for phylogenetic analysis, although more intensive research on this with using comprehensive marker sets, such as large sequence polymorphisms and single-nucleotide polymorphisms are required. Again, with the advantages of VNTR analysis, i.e., easy, rapid, specific, and digit-based data, VNTR became the first line method in molecular epidemiology. Molecular epidemiology of tuberculosis is expanding its research field from the investigation of TB transmission to more basic science such as evolution and phylogeographic distribution. In this symposium, we have invited four opinion leaders in molecular epidemiology of TB in Japan who are talking about each title as followed. 1. Establishment of the standard VNTR analysis systems for Tuberculosis (TB) and preparation of databases for TB genotyping: Shinji MAEDA and Yoshiro MURASE (Department of Mycobacterium Reference and Research, Research Institute of Tuberculosis, JATA). We have already reported the JATA (12)-VNTR system for TB genotyping in Japan. However, by comparison of cluster formation rate, the discrimination power of JATA (12)-VNTR was lower than that of IS6110 RFLP analysis. Therefore, we improved the JATA (12

  6. [From molecular to genomic and metagenomic epidemiology].

    PubMed

    Zhebrun, A B

    2014-01-01

    The notion "molecular epidemiology" was introduced into scientific literature by Kilburn E. et al. in 1973. The first period of development of infectious diseases molecular epidemiology may be called "genotypic" (1980-1990s). During this period methodology of molecular marking of pathogens for purposes of monitoring of their spread and outbreak detection (novel nomenclature of diphtheria corynebacteria based on ribotyping; international network PulseNet for monitoring food source infections; international database of tuberculosis mycobacteria spoligotypes) was created. The second--"genomic" period started in the 2000s. Molecular epidemiology rapidly went through single markers (genotypes or single genes) to deciphering the whole genome of pathoge "mobileome", "resistome", "virulome" etc. took an important place in the studies of emerging and pandemic infections. Knowledge on genetic mechanisms leading to emergence and global dissemination of novel pathogens give molecular epidemiology its own scientific content and transforms it from a methodical approach to an independent field of epidemiology. The third--"metagenomic" period starts nowadays based on meta-genomic approach that allows to determine the whole set ofgenomes in the studied sample without the cultivation procedure. In the short-term this would lead to a change of a century-long paradigm of diagnostics and control of infections: instead of search of separate (key) pathogens--characteristics of the full specter of microorganisms in the material from patients and environmental samples with its identification up to any taxonomic depth. In the systems of regional and global epidemiologic control a universal monitoring of all known and re-emerging pathogens with construction and maintenance of metagenomic passports of human habitats will be realized. PMID:25286516

  7. [From molecular to genomic and metagenomic epidemiology].

    PubMed

    Zhebrun, A B

    2014-01-01

    The notion "molecular epidemiology" was introduced into scientific literature by Kilburn E. et al. in 1973. The first period of development of infectious diseases molecular epidemiology may be called "genotypic" (1980-1990s). During this period methodology of molecular marking of pathogens for purposes of monitoring of their spread and outbreak detection (novel nomenclature of diphtheria corynebacteria based on ribotyping; international network PulseNet for monitoring food source infections; international database of tuberculosis mycobacteria spoligotypes) was created. The second--"genomic" period started in the 2000s. Molecular epidemiology rapidly went through single markers (genotypes or single genes) to deciphering the whole genome of pathoge "mobileome", "resistome", "virulome" etc. took an important place in the studies of emerging and pandemic infections. Knowledge on genetic mechanisms leading to emergence and global dissemination of novel pathogens give molecular epidemiology its own scientific content and transforms it from a methodical approach to an independent field of epidemiology. The third--"metagenomic" period starts nowadays based on meta-genomic approach that allows to determine the whole set ofgenomes in the studied sample without the cultivation procedure. In the short-term this would lead to a change of a century-long paradigm of diagnostics and control of infections: instead of search of separate (key) pathogens--characteristics of the full specter of microorganisms in the material from patients and environmental samples with its identification up to any taxonomic depth. In the systems of regional and global epidemiologic control a universal monitoring of all known and re-emerging pathogens with construction and maintenance of metagenomic passports of human habitats will be realized.

  8. Feminism meets the "new" epidemiologies: toward an appraisal of antifeminist biases in epidemiological research on women's health.

    PubMed

    Inhorn, M C; Whittle, K L

    2001-09-01

    This essay explores an alternative paradigm for epidemiology, one which is explicitly informed by a feminist perspective. We intend to expand upon recent critiques and debates within the emergent fields of "critical", "popular", and "alternative" epidemiology to examine how epidemiology's conceptual models--which are meant to contribute to the prevention of social inequalities in health, but may instead reinforce social hierarchies based on gender, race, and class--constrain our understanding of health and disease. Specifically, we examine persistent antifeminist biases in contemporary epidemiological research on women's health. Issues highlighted include: problem definition and knowledge production in women's health: biological essentialization of women as reproducers; and decontextualization and depoliticization of women's health risks. As part of this critique, we include suggestions for an emancipatory epidemiology that incorporates an alternative feminist framework.

  9. Feminism meets the "new" epidemiologies: toward an appraisal of antifeminist biases in epidemiological research on women's health.

    PubMed

    Inhorn, M C; Whittle, K L

    2001-09-01

    This essay explores an alternative paradigm for epidemiology, one which is explicitly informed by a feminist perspective. We intend to expand upon recent critiques and debates within the emergent fields of "critical", "popular", and "alternative" epidemiology to examine how epidemiology's conceptual models--which are meant to contribute to the prevention of social inequalities in health, but may instead reinforce social hierarchies based on gender, race, and class--constrain our understanding of health and disease. Specifically, we examine persistent antifeminist biases in contemporary epidemiological research on women's health. Issues highlighted include: problem definition and knowledge production in women's health: biological essentialization of women as reproducers; and decontextualization and depoliticization of women's health risks. As part of this critique, we include suggestions for an emancipatory epidemiology that incorporates an alternative feminist framework. PMID:11478536

  10. Field Evaluation of Dried Blood Spots for Routine HIV-1 Viral Load and Drug Resistance Monitoring in Patients Receiving Antiretroviral Therapy in Africa and Asia

    PubMed Central

    Monleau, Marjorie; Eymard-Duvernay, Sabrina; Dagnra, Anoumou; Kania, Dramane; Ngo-Giang-Huong, Nicole; Touré-Kane, Coumba; Truong, Lien X. T.; Chaix, Marie-Laure; Delaporte, Eric; Ayouba, Ahidjo; Peeters, Martine

    2014-01-01

    Dried blood spots (DBS) can be used in developing countries to alleviate the logistic constraints of using blood plasma specimens for viral load (VL) and HIV drug resistance (HIVDR) testing, but they should be assessed under field conditions. Between 2009 and 2011, we collected paired plasma-DBS samples from treatment-experienced HIV-1-infected adults in Burkina Faso, Cameroon, Senegal, Togo, Thailand, and Vietnam. The DBS were stored at an ambient temperature for 2 to 4 weeks and subsequently at −20°C before testing. VL testing was performed on the plasma samples and DBS using locally available methods: the Abbott m2000rt HIV-1 test, generic G2 real-time PCR, or the NucliSENS EasyQ version 1.2 test. In the case of virological failure (VF), i.e., a plasma VL of ≥1,000 copies/ml, HIVDR genotyping was performed on paired plasma-DBS samples. Overall, we compared 382 plasma-DBS sample pairs for DBS VL testing accuracy. The sensitivities of the different assays in different laboratories for detecting VF using DBS varied from 75% to 100% for the m2000rt test in labs B, C, and D, 91% to 93% for generic G2 real-time PCR in labs A and F, and 85% for the NucliSENS test in lab E. The specificities varied from 82% to 97% for the m2000rt and NucliSENS tests and reached only 60% for the generic G2 test. The NucliSENS test showed good agreement between plasma and DBS VL but underestimated the DBS VL. The lowest agreement was observed for the generic G2 test. Genotyping was successful for 96/124 (77%) DBS tested, and 75/96 (78%) plasma-DBS pairs had identical HIVDR mutations. Significant discrepancies in resistance interpretations were observed in 9 cases, 6 of which were from the same laboratory. DBS can be successfully used as an alternative to blood plasma samples for routine VL and HIVDR monitoring in African and Asian settings. However, the selection of an adequate VL measurement method and the definition of the VF threshold should be considered, and laboratory

  11. Field evaluation of dried blood spots for routine HIV-1 viral load and drug resistance monitoring in patients receiving antiretroviral therapy in Africa and Asia.

    PubMed

    Monleau, Marjorie; Aghokeng, Avelin F; Eymard-Duvernay, Sabrina; Dagnra, Anoumou; Kania, Dramane; Ngo-Giang-Huong, Nicole; Touré-Kane, Coumba; Truong, Lien X T; Chaix, Marie-Laure; Delaporte, Eric; Ayouba, Ahidjo; Peeters, Martine

    2014-02-01

    Dried blood spots (DBS) can be used in developing countries to alleviate the logistic constraints of using blood plasma specimens for viral load (VL) and HIV drug resistance (HIVDR) testing, but they should be assessed under field conditions. Between 2009 and 2011, we collected paired plasma-DBS samples from treatment-experienced HIV-1-infected adults in Burkina Faso, Cameroon, Senegal, Togo, Thailand, and Vietnam. The DBS were stored at an ambient temperature for 2 to 4 weeks and subsequently at -20°C before testing. VL testing was performed on the plasma samples and DBS using locally available methods: the Abbott m2000rt HIV-1 test, generic G2 real-time PCR, or the NucliSENS EasyQ version 1.2 test. In the case of virological failure (VF), i.e., a plasma VL of ≥1,000 copies/ml, HIVDR genotyping was performed on paired plasma-DBS samples. Overall, we compared 382 plasma-DBS sample pairs for DBS VL testing accuracy. The sensitivities of the different assays in different laboratories for detecting VF using DBS varied from 75% to 100% for the m2000rt test in labs B, C, and D, 91% to 93% for generic G2 real-time PCR in labs A and F, and 85% for the NucliSENS test in lab E. The specificities varied from 82% to 97% for the m2000rt and NucliSENS tests and reached only 60% for the generic G2 test. The NucliSENS test showed good agreement between plasma and DBS VL but underestimated the DBS VL. The lowest agreement was observed for the generic G2 test. Genotyping was successful for 96/124 (77%) DBS tested, and 75/96 (78%) plasma-DBS pairs had identical HIVDR mutations. Significant discrepancies in resistance interpretations were observed in 9 cases, 6 of which were from the same laboratory. DBS can be successfully used as an alternative to blood plasma samples for routine VL and HIVDR monitoring in African and Asian settings. However, the selection of an adequate VL measurement method and the definition of the VF threshold should be considered, and laboratory performance

  12. Molecular Epidemiology of Foodborne Pathogens

    NASA Astrophysics Data System (ADS)

    Chen, Yi; Brown, Eric; Knabel, Stephen J.

    The purpose of this chapter is to describe the basic principles and advancements in the molecular epidemiology of foodborne pathogens. Epidemiology is the study of the distribution and determinants of infectious diseases and/or the dynamics of disease transmission. The goals of epidemiology include the identification of physical sources, routes of transmission of infectious agents, and distribution and relationships of different subgroups. Molecular epidemiology is the study of epidemiology at the molecular level. It has been defined as "a science that focuses on the contribution of potential genetic and environmental risk factors, identified at the molecular level, to the etiology, distribution and prevention of diseases within families and across populations".

  13. PPP insights in South Africa.

    PubMed

    du Toit, Japie

    2003-01-01

    After functioning for some time in an increasingly regulated and structured environment in dealing with the private sector in South Africa, it was important to Government, to carefully review the terminology used in this evolving playing field. As the definitions and mechanisms impacting on this form of interaction became clear, it was essential to find a broader definition to encompass all forms of commercial intervention between the two sectors. In preparation for the first South African National Health Summit during 2001, the term public private interaction became a general term used in this context. In the South African healthcare sectors this term is used specifically to indicate that all forms of interaction between the two sectors should be considered, rather than merely focussing on specific Public Private Partnerships (PPPs), that have a much more narrow definition. Recent health policy documents in South Africa all stress four key goals--equity, coherence, quality of care and efficiency--which provide a useful basis for decision-making about PPIs. The range of public-private interactions that may support or constrain the South African health system's development are set within the overall public/private mix of the country. In developing an equitable, efficient, coherent and high quality health system in South Africa, there is considerable potential for constructive engagement (collaboration and co-operation) between the public and the private health care sectors. Both sectors should embrace this opportunity and therefore it is useful to propose some basic guidelines for engagement based on the vision and goals of the national health system. In deciding whether or not to pursue any new PPI within the health sector, or in evaluating whether an existing PPI should continue or be revised, it is necessary to assess its merits in relation to the achievement of health system goals.

  14. Meningococcal disease: changes in epidemiology and prevention.

    PubMed

    Chang, Qiuzhi; Tzeng, Yih-Ling; Stephens, David S

    2012-01-01

    The human bacterial pathogen Neisseria meningitidis remains a serious worldwide health threat, but progress is being made toward the control of meningococcal infections. This review summarizes current knowledge of the global epidemiology and the pathophysiology of meningococcal disease, as well as recent advances in prevention by new vaccines. Meningococcal disease patterns and incidence can vary dramatically, both geographically and over time in populations, influenced by differences in invasive meningococcal capsular serogroups and specific genotypes designated as ST clonal complexes. Serogroup A (ST-5, ST-7), B (ST-41/44, ST-32, ST-18, ST-269, ST-8, ST-35), C (ST-11), Y (ST-23, ST-167), W-135 (ST-11) and X (ST-181) meningococci currently cause almost all invasive disease. Serogroups B, C, and Y are responsible for the majority of cases in Europe, the Americas, and Oceania; serogroup A has been associated with the highest incidence (up to 1000 per 100,000 cases) and large outbreaks of meningococcal disease in sub-Saharan Africa and previously Asia; and serogroups W-135 and X have emerged to cause major disease outbreaks in sub-Saharan Africa. Significant declines in meningococcal disease have occurred in the last decade in many developed countries. In part, the decline is related to the introduction of new meningococcal vaccines. Serogroup C polysaccharide-protein conjugate vaccines were introduced over a decade ago, first in the UK in a mass vaccination campaign, and are now widely used; multivalent meningococcal conjugate vaccines containing serogroups A, C, W-135, and/or Y were first used for adolescents in the US in 2005 and have now expanded indications for infants and young children, and a new serogroup A conjugate vaccine has recently been introduced in sub-Saharan Africa. The effectiveness of these conjugate vaccines has been enhanced by the prevention of person-to-person transmission and herd immunity. In addition, progress has been made in serogroup B

  15. Meningococcal disease: changes in epidemiology and prevention

    PubMed Central

    Chang, Qiuzhi; Tzeng, Yih-Ling; Stephens, David S

    2012-01-01

    The human bacterial pathogen Neisseria meningitidis remains a serious worldwide health threat, but progress is being made toward the control of meningococcal infections. This review summarizes current knowledge of the global epidemiology and the pathophysiology of meningococcal disease, as well as recent advances in prevention by new vaccines. Meningococcal disease patterns and incidence can vary dramatically, both geographically and over time in populations, influenced by differences in invasive meningococcal capsular serogroups and specific genotypes designated as ST clonal complexes. Serogroup A (ST-5, ST-7), B (ST-41/44, ST-32, ST-18, ST-269, ST-8, ST-35), C (ST-11), Y (ST-23, ST-167), W-135 (ST-11) and X (ST-181) meningococci currently cause almost all invasive disease. Serogroups B, C, and Y are responsible for the majority of cases in Europe, the Americas, and Oceania; serogroup A has been associated with the highest incidence (up to 1000 per 100,000 cases) and large outbreaks of meningococcal disease in sub-Saharan Africa and previously Asia; and serogroups W-135 and X have emerged to cause major disease outbreaks in sub-Saharan Africa. Significant declines in meningococcal disease have occurred in the last decade in many developed countries. In part, the decline is related to the introduction of new meningococcal vaccines. Serogroup C polysaccharide-protein conjugate vaccines were introduced over a decade ago, first in the UK in a mass vaccination campaign, and are now widely used; multivalent meningococcal conjugate vaccines containing serogroups A, C, W-135, and/or Y were first used for adolescents in the US in 2005 and have now expanded indications for infants and young children, and a new serogroup A conjugate vaccine has recently been introduced in sub-Saharan Africa. The effectiveness of these conjugate vaccines has been enhanced by the prevention of person-to-person transmission and herd immunity. In addition, progress has been made in serogroup B

  16. Field experiments of Anopheles gambiae attraction to local fruits/seedpods and flowering plants in Mali to optimize strategies for malaria vector control in Africa using attractive toxic sugar bait methods

    PubMed Central

    2010-01-01

    Background Based on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB) methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. The ATSB approach uses fruit or flower scent as an attractant, sugar solution as a feeding stimulant, and an oral toxin. The ATSB solutions are either sprayed on vegetation or suspended in simple bait stations, and the mosquitoes ingesting the toxic solutions are killed. As such, this approach targets sugar-feeding female and male mosquitoes. This study examines the attractiveness of African malaria vectors to local fruits/seedpods and flowering plants, key biological elements of the ATSB approach for mosquito control. Methods Three field experiments were conducted at sites in Mali. The attraction of Anopheles gambiae s.l. to 26 different local fruits and seedpods was determined at a site in the semi-arid Bandiagara District of Mali. Wire mesh glue traps with fruits/seedpods suspended on skewers inside were set along a seasonal lagoon. Seven replicates of each fruit/seedpod species were tested, with a water-soaked sponge and a sugar-soaked sponge as controls. The attraction of An. gambiae s.l. to 26 different types of flowering plants was determined at a site near Mopti in Mali. The flowering plants held in a water-filled buried container were tested using the same glue traps, with controls including water only and sugar solution. Six replicates of each selected plant type were tested on transects between rice paddies. Additional studies using CDC light traps were done to determine the relative densities and periodicity of An. gambiae s.l. attraction to branches of the most highly attractive flowering plant, branches without flowers, human odor, and candescent light. Results Of the 26 fruits and seedpods tested, 6 were attractive to An. gambiae s.l. females

  17. Epidemiology and moral philosophy.

    PubMed Central

    Westrin, C G; Nilstun, T; Smedby, B; Haglund, B

    1992-01-01

    To an increasing extent ethical controversies affect and sometimes obstruct public health work and epidemiological research. In order to improve communication between the concerned parties a model for identification and analysis of ethical conflicts in individual-based research has been worked out in co-operation between epidemiologists and moral philosophers. The model has two dimensions. One dimension specifies relevant ethical principles (as beneficence, non-maleficence, autonomy and justice). The other dimension specifies the groups of persons involved in the conflict under consideration (for example: the study-population, individuals who may benefit from the results, the researchers and their personnel, the community at large). The model has been applied to the problem of legitimacy of case-register research and to problems in psychiatric health services research as well as epidemiological research. PMID:1460647

  18. Dengue: update on epidemiology.

    PubMed

    Wilson, Mary Elizabeth; Chen, Lin H

    2015-01-01

    The epidemiology of dengue fever has undergone major shifts in recent decades. The global distribution has expanded to include more geographic areas. The intensity of transmission and the severity of infections have increased in areas where infection was already endemic. Multiple studies provide a clearer picture of the epidemiology and allow mapping of its distribution and change over time. Despite major efforts to control transmission, competent vectors now infest most tropical and subtropical regions; Aedes albopictus, also a competent vector, is able to survive in temperate areas, placing parts of Europe and North America at risk for local transmission. Many research teams in dengue-endemic areas are working to identify key local weather, vector, and other variables that would allow prediction of a likely epidemic early enough to permit interventions to avert it or blunt its impact.

  19. Epidemiology of colorectal cancer

    PubMed Central

    Marley, Andrew R; Nan, Hongmei

    2016-01-01

    Colorectal cancer is currently the third deadliest cancer in the United States and will claim an estimated 49,190 U.S. lives in 2016. The purpose of this review is to summarize our current understanding of this disease, based on nationally published statistics and information presented in peer-reviewed journal articles. Specifically, this review will cover the following topics: descriptive epidemiology (including time and disease trends both in the United States and abroad), risk factors (environmental, genetic, and gene-environment interactions), screening, prevention and control, and treatment. Landmark discoveries in colorectal cancer risk factor research will also be presented. Based on the information reviewed for this report, we suggest that future U.S. public health efforts aim to increase colorectal cancer screening among African American communities, and that future worldwide colorectal cancer epidemiology studies should focus on researching nutrient-gene interactions towards the goal of improving personalized treatment and prevention strategies. PMID:27766137

  20. Epidemiology of venous thromboembolism.

    PubMed Central

    Coon, W W

    1977-01-01

    This review of the epidemiology of venous thromboembolism includes estimates of incidence and prevalence of venous thrombosis and its sequelae, a discussion geographical, annual and seasonal variations and data concerning possible risk factors. Selection of patients at increased risk for development of deep venous thrombosis or pulmonary embolism for specific diagnostic screening or for prophylactic therapy with low-dose heparin may be a more effective approach to lowering morbidity and mortality from this disease. PMID:329779

  1. [Acute coronary syndromes: epidemiology].

    PubMed

    Ozkan, Alev Arat

    2013-04-01

    Coronary heart disease is the main cause of death in the world as well as in Turkey. It's not only a health issue but also a social problem with a high economic burden and negative impact on quality of life. The majority of deaths are attributable to acute coronary syndromes (ACS) and their complications.This review summarizes some important facts regarding ACS epidemiology in the world and in Turkey. PMID:27323430

  2. Epidemiology of epilepsy.

    PubMed

    Abramovici, S; Bagić, A

    2016-01-01

    Modern epidemiology of epilepsy maximizes the benefits of advanced diagnostic methods and sophisticated techniques for case ascertainment in order to increase the diagnostic accuracy and representativeness of the cases and cohorts studied, resulting in better comparability of similarly performed studies. Overall, these advanced epidemiologic methods are expected to yield a better understanding of diverse risk factors, high-risk populations, seizure triggers, multiple and poorly understood causes of epilepsy, including the increasing and complex role of genetics, and establish the natural course of treated and untreated epilepsy and syndromes - all of which form the foundation of an attempt to prevent epileptogenesis as the primary prophylaxis of epilepsy. Although data collection continues to improve, epidemiologists still need to overcome definition and coding variability, insufficient documentation, as well as the interplay of socioeconomic factors and stigma. As most of the 65-70 million people with epilepsy live outside of resource-rich countries, extensive underdiagnosis, misdiagnosis, and undertreatment are likely. Epidemiology will continue to provide the necessary information to the medical community, public, and regulators as the foundation for improved health policies, targeted education, and advanced measures of prevention and prognostication of the most common severe brain disorder. PMID:27637958

  3. Tobacco in Africa.

    PubMed

    Yach, D

    1996-01-01

    Tobacco has been a common commodity in Africa for over three centuries. By 1993, some 500 000 tons of tobacco were being grown in 33 African countries, with only two countries exporting more than they import. Attempts to measure the current and potential impact of the tobacco business on health, society and the environment are still in their early stages, but the need for preventive action is already inescapably clear. Comprehensive control strategies are urgently required to prevent a major epidemic of tobacco-related disease in Africa. PMID:8820139

  4. Epidemiology and pathogenesis of Kaposi's sarcoma-associated herpesvirus.

    PubMed Central

    Boshoff, C; Weiss, R A

    2001-01-01

    Kaposi's sarcoma (KS) occurs in Europe and the Mediterranean countries (classic KS) and Africa (endemic KS), immunosuppressed patients (iatrogenic or post-transplant KS) and those with acquired immune deficiency syndrome (AIDS), especially among those who acquired human immunodeficiency virus sexually (AIDS-KS). KS-associated herpesvirus (KSHV or HHV-8) is unusual among herpesviruses in having a restricted geographical distribution. Like KS, which it induces in immunosuppressed or elderly people, the virus is prevalent in Africa, in Mediterranean countries, among Jews and Arabs and certain Amerindians. Distinct KSHV genotypes occur in different parts of the world, but have not been identified as having a differential pathogenesis. KSHV is aetiologically linked to three distinct neoplasms: (i) KS, (ii) primary effusion lymphoma, and (iii) plasmablastic multicentric Castleman's disease. The histogenesis, clonality and pathology of the tumours are described, together with the epidemiology and possible modes of transmission of the virus. PMID:11313009

  5. Telecommunications and Development in Africa.

    ERIC Educational Resources Information Center

    Kiplagat, B. A., Ed.; Werner, M. C. M., Ed.

    The Telecommunications Foundation of Africa (TFA) was created in 1992 out of a conviction that insufficient telecommunications in Africa are an impediment to economic growth, and that more resources could be mobilized to strengthen this sector. This volume was made by TFA for readers both inside and outside of Africa and the telecommunications…

  6. Family Planning Programmes in Africa.

    ERIC Educational Resources Information Center

    Pradervand, Pierre

    The countries discussed in this paper are the francophone countries of West Africa and the Republic of Congo, with comparative references made to North Africa (mainly Morocco, Algeria, and Tunisia). Obstacles to the adoption of family planning in the countries of tropical Africa are a very high mortality rate among children; a socioeconomic…

  7. Country Energy Profile, South Africa

    SciTech Connect

    1995-08-01

    This country energy profile provides energy and economic information about South Africa. Areas covered include: Economics, demographics, and environment; Energy situation; Energy structure; Energy investment opportunities; Department of Energy (DOE) programs in South Africa; and a listing of International aid to South Africa.

  8. Epidemiology, prenatal management, and prevention of neural tube defects

    PubMed Central

    Salih, Mustafa A.; Murshid, Waleed R.; Seidahmed, Mohammed Z.

    2014-01-01

    This review article discusses the epidemiology, risk factors, prenatal screening, diagnosis, prevention potentials, and epidemiologic impact of neural tube defects (NTDs). The average incidence of NTDs is 1/1000 births, with a marked geographic variation. In the developed countries, the incidence of NTDs has fallen over recent decades. However, it still remains high in the less-developed countries in Latin America, Africa, the Middle East, Asia, and the Far East (>1 to 11/1000 births). Recognized NTDs risks include maternal diabetes, obesity, lower socioeconomic status, hyperthermia, and exposure to certain teratogens during the periconceptional period. Periconceptional folic acid supplementation decreased the prevalence of NTDs by 50-70%, and an obligatory folic acid fortification of food was adopted in several countries to reach women with unplanned pregnancies and those facing social deprivation. Prevention of NTDs can be accelerated if more, especially low income countries, adopted fortification of the staple food in their communities. PMID:25551106

  9. [Imported malaria in Sicily (Italy): epidemiology and recommendations for prevention].

    PubMed

    Immordino, Palmira; Palmeri, Sara; D'Angelo, Claudio; Casuccio, Nicolò; Scondotto, Salvatore; Casuccio, Alessandra

    2015-01-01

    This study analysed cases of imported malaria notified to the District Health Units of Palermo from 1998 to 2014. The aim was to assess epidemiological differences among cases, related to their reasons for travel. Eighty one cases were reported: 83% developed symptoms following a trip to Africa while 17% had travelled to Asia. Seventy-three percent of cases had travelled to visit family or friends in malaria-endemic countries (Visiting Friends and Relatives: VFRs), confirming the need for preventive measures targeted towards this at-risk population group. PMID:26847273

  10. The epidemiology of Plasmodium falciparum gametocytes: weapons of mass dispersion.

    PubMed

    Drakeley, Chris; Sutherland, Colin; Bousema, J Teun; Sauerwein, Robert W; Targett, Geoffrey A T

    2006-09-01

    Much of the epidemiology of Plasmodium falciparum in Sub-Saharan Africa focuses on the prevalence patterns of asexual parasites in people of different ages, whereas the gametocytes that propagate the disease are often neglected. One expected benefit of the widespread introduction of artemisinin-based combination therapy for malaria is a reduction in gametocyte carriage. However, the factors that affect the transmission of parasites from humans to mosquitoes show complex dynamics in relation to the intensity and seasonality of malaria transmission, and thus such benefits might not be automatic. Here, we review data on gametocyte carriage in the context of the development of naturally acquired immunity and population infectivity. PMID:16846756

  11. [Imported malaria in Sicily (Italy): epidemiology and recommendations for prevention].

    PubMed

    Immordino, Palmira; Palmeri, Sara; D'Angelo, Claudio; Casuccio, Nicolò; Scondotto, Salvatore; Casuccio, Alessandra

    2015-01-01

    This study analysed cases of imported malaria notified to the District Health Units of Palermo from 1998 to 2014. The aim was to assess epidemiological differences among cases, related to their reasons for travel. Eighty one cases were reported: 83% developed symptoms following a trip to Africa while 17% had travelled to Asia. Seventy-three percent of cases had travelled to visit family or friends in malaria-endemic countries (Visiting Friends and Relatives: VFRs), confirming the need for preventive measures targeted towards this at-risk population group.

  12. Global foot-and-mouth disease reearch update and gap analysis: 2 - epidemiology, wildlife and economics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2014, the Global Foot-and-mouth disease Research ings in the fields of (i) epidemiology, (ii) wildlife and (iii) Alliance (GFRA) conducted a gap analysis of foot-and- economics. Although the three sections, epidemiology, wildlife and economics are presented as separate entities, the fields are ...

  13. Vaccination for typhoid fever in sub-Saharan Africa.

    PubMed

    Slayton, Rachel B; Date, Kashmira A; Mintz, Eric D

    2013-04-01

    Emerging data on the epidemiologic, clinical and microbiologic aspects of typhoid fever in sub-Saharan Africa call for new strategies and new resources to bring the regional epidemic under control. Areas with endemic disease at rates approaching those in south Asia have been identified; large, prolonged and severe outbreaks are occurring more frequently; and resistance to antimicrobial agents, including fluoroquinolones is increasing. Surveillance for typhoid fever is hampered by the lack of laboratory resources for rapid diagnosis, culture confirmation and antimicrobial susceptibility testing. Nonetheless, in 2010, typhoid fever was estimated to cause 725 incident cases and 7 deaths per 100,000 person years in sub-Saharan Africa. Efforts for prevention and outbreak control are challenged by limited access to safe drinking water and sanitation and by a lack of resources to initiate typhoid immunization. A comprehensive approach to typhoid fever prevention including laboratory and epidemiologic capacity building, investments in water, sanitation and hygiene and reconsideration of the role of currently available vaccines could significantly reduce the disease burden. Targeted vaccination using currently available typhoid vaccines should be considered as a short- to intermediate-term risk reduction strategy for high-risk groups across sub-Saharan Africa.

  14. Pythiosis in Africa

    PubMed Central

    Rivierre, Christine; Laprie, Caroline; Guiard-Marigny, Olivier; Bergeaud, Patrick; Berthelemy, Madeleine

    2005-01-01

    We report the first case of pythiosis from Africa in an 8-month-old dog with a chronic and ulcerative cutaneous lesion. The etiologic agent belonged to the genus Pythium. Phylogenetic analysis placed the isolate in a sister group to the other P. insidiosum strains. However, the isolate may belong to a new Pythium species. PMID:15757572

  15. Photomontage. Water in Africa.

    ERIC Educational Resources Information Center

    McKoski, David

    The Water in Africa Project was realized over a 2-year period by a team of Peace Corps volunteers. As part of an expanded, detailed design, resources were collected from over 90 volunteers serving in African countries, photos and stories were prepared, and standards-based learning units were created for K-12 students. This unit, "Photomontage,"…

  16. Anglicising Postapartheid South Africa

    ERIC Educational Resources Information Center

    Louw, P. Eric

    2004-01-01

    The apartheid state deliberately encouraged linguistic diversity and actively built cultural infrastructures which impeded Anglicisation. With the end of apartheid has come "de facto" Anglicisation. So although South Africa has, since 1994, had 11 official languages, in reality, English is swamping the other 10 languages. Afrikaans has, in…

  17. Topical Research: Africa.

    ERIC Educational Resources Information Center

    Lynn, Karen

    This lesson plan can be used in social studies, language arts, or library research. The instructional objective is for students to select a topic of study relating to Africa, write a thesis statement, collect information from media sources, and develop a conclusion. The teacher may assign the lesson for written or oral evaluation. The teacher…

  18. Out of Africa

    ERIC Educational Resources Information Center

    Wilbert, Nancy Corrigan

    2009-01-01

    Karen Blixen (Isak Dinesen), author of "Out of Africa," said, "God made the world round so people would never be able to see too far down the road." The author embraced this wonderful thought by venturing on a three-week journey to Kenya and Tanzania in search of grand adventure. In this article, the author shares her adventure with her students…

  19. Africa: Myth and Reality.

    ERIC Educational Resources Information Center

    Brown, Barbara B.

    1994-01-01

    Reports on the Third International Social Studies Conference held in Nairobi, Kenya, in 1994. Discusses democracy, educational reform efforts, and the importance of tourism to the Kenyan economy. Asserts that U.S. teachers must use accurate and nonstereotypical instructional materials in teaching about Africa. (CFR)

  20. West and Central Africa.

    PubMed

    Lydie, N; Robinson, N J

    1998-01-01

    This article reviews scientific and other literature during the 1990s that links migration and mobility with the spread of sexually transmitted diseases (STDs), including HIV/AIDS. The focus is on key population groups linked to the spread of HIV and STDs in West and Central Africa: migrant laborers, truck drivers, itinerant traders, commercial sex workers (CSWs), and refugees. Countries with high emigration and immigration tend to have high levels of HIV infection, with the exception of Senegal. The main destination of immigrants are Senegal, Nigeria, and Cote d'Ivoire in West Africa and Cameroon, Congo, Gabon, and Congo in Central Africa. The risk of infection and the spread of HIV is variable among migrants. There is little in the literature that substantiates hypotheses about the strong association between migration and HIV-positive status. Information is needed on the duration, frequency of return visits, living conditions, sexual activities with multiple partners, and information before departure, along the routes, at final destination, and at the time of returns. Action-based research in five West African countries (Burkina Faso, Cote d'Ivoire, Mali, Niger, and Senegal) should produce results in late 1998. Comparable studies in Central Africa are unknown. Regional studies should be complemented by local studies. Prevention would benefit from studies on the relative size of these five population groups by geographic location.

  1. South Africa's Constitutional Change.

    ERIC Educational Resources Information Center

    Getman, Thomas

    1987-01-01

    Describes the striking dichotomy of South Africa's beauty and the squalor resulting from the apartheid policies of the government. Reviews reactions of black South Africans to recent constitutional changes and details efforts to secure more sweeping reform. Includes stories of several individuals who have taken actions which oppose the system of…

  2. Trends Abroad: South Africa

    ERIC Educational Resources Information Center

    Varley, Douglas H.

    1970-01-01

    In South Africa today there is a complex structure of laws and regulations which impose a variety of restrictions on individual liberties including the freedom to publish and read literary material. The successive steps by which this state of affairs has been reached are briefly described. (NH)

  3. Education in Africa.

    ERIC Educational Resources Information Center

    Educational Documentation and Information, 1977

    1977-01-01

    This selected, annotated bibliography of information resources in English and/or French is divided into sections on books; documents and articles; UNESCO publications; reference works; and African periodicals. A list of institutions concerned with education in Africa is included, as well as educational documentation and information services in…

  4. AED in Africa

    ERIC Educational Resources Information Center

    Academy for Educational Development, 2004

    2004-01-01

    Founded in 1961, the Academy for Educational Development (AED) is an independent, nonprofit, charitable organization that operates development programs in the United States and throughout the world. This directory presents an overview of the AED programs in Africa since 1975. Current AED Programs include: (1) HIV/AIDS Prevention and Impact…

  5. Neonatal surgery in Africa.

    PubMed

    Chirdan, Lohfa B; Ngiloi, Petronilla J; Elhalaby, Essam A

    2012-05-01

    The management of neonatal surgical problems continues to pose considerable challenges, particularly in low-resource settings. The burden of neonatal surgical diseases in Africa is not well documented. The characteristics of some neonatal surgical problems are highlighted. Late presentation coupled with poor understanding of the milieu interior of the neonates by incompetent health care providers and poorly equipped hospitals combine to give rise to the unacceptable high morbidity and mortality in most parts of Africa. Proper training of all staff involved in neonatal health care coupled with community awareness must be vigorously pursued by all stakeholders. Various governments throughout the continent of Africa, in conjunction with international donor agencies, must not only provide an adequate budget for health care services and improve infrastructures, but must also deliberately encourage and provide funding for neonatal surgical care and research across the continent. The well-established pediatric surgical training programs, particularly in North and South Africa, should hold the moral responsibility of training all possible numbers of young surgeons from other African countries that do not have any existing pediatric surgical training programs or those countries suffering from remarkable shortage of trained pediatric surgeons.

  6. Africa and Applied Linguistics.

    ERIC Educational Resources Information Center

    Makoni, Sinfree, Ed.; Meinhof, Ulrike H., Ed.

    2003-01-01

    This collection of articles includes: "Introducing Applied Linguistics in Africa" (Sinfree Makoni and Ulrike H. Meinhof); "Language Ideology and Politics: A Critical Appraisal of French as Second Official Language in Nigeria" (Tope Omoniyi); "The Democratisation of Indigenous Languages: The Case of Malawi" (Themba Moyo); "Classroom Code-Switching…

  7. Literacy in Francophone Africa.

    ERIC Educational Resources Information Center

    Kokora, Pascal D.

    1991-01-01

    Literacy in francophone Africa, where literacy is still a privilege, is reviewed in terms of the complex linguistic situation, effects of population change, concepts and definitions of literacy, promotion of literacy in adult nonformal settings (e.g., African language literacy materials, multilingual settings). (23 references) (LB)

  8. Short shrift for Africa.

    PubMed

    Collymore, Y

    1994-01-01

    The plan of action that emerged from the International Conference on Population and development (ICPD) held in Cairo in September 1994 did not directly address the major problems of pervasive poverty and dismal infant and maternal mortality rates in Africa. The Organization of African Unity met the week before ICPD to develop an integrated population and development strategy. The continent's population growth rate of 3% far exceeds that in most other developing countries; the maternal mortality rate is 640/100,000 live births vs. only 30 for industrialized countries. Its infant mortality rate is 114 deaths/1000 live births--double that of Western Europe. Africa's annual requirements under the Cairo plan for environmental, population, and development strategies would be $2.2-3 billion during 1995-2000. The estimated needs will grow to $4.3-5.6 billion by the year 2015. However, Botswana, Lesotho, Malawi, Mozambique, Namibia, Swaziland, and South Africa warned against these ambitious goals, preferring instead individual national targets. South Africa is compiling population data that indicate that the rate of growth is 2%/year with a current estimated population of 40 million. A population policy is being considered within the context of reconstruction and development. Namibia also faces a growing population that could compromise economic development. Some nongovernmental organizations have stated that the ICPD failed to confront unsafe abortions and reproductive health problems in an effort to appease the Vatican and Islamic countries. Women's reproductive and sexual rights have also been rejected by some Latin American and Islamic countries as alien to their laws and culture. Nevertheless, an agreement was reached on information and access to family planning services for teenagers and counseling on responsible sexual behavior. There were also charges from African delegates about diverting attention from the internecine conflicts in Africa that have resulted in

  9. Trichinosis: Epidemiology in Thailand

    PubMed Central

    Kaewpitoon, Natthawut; Kaewpitoon, Soraya Jatesadapattaya; Philasri, Chutikan; Leksomboon, Ratana; Maneenin, Chanvit; Sirilaph, Samaporn; Pengsaa, Prasit

    2006-01-01

    Trichinosis is one of the most common food-borne parasitic zoonoses in Thailand and many outbreaks are reported each year. This paper reviews the history, species, and epidemiology of the disease and food habits of the people with an emphasis on the north, northeast, central and south regions of Thailand. The earliest record of trichinosis in Thailand was in 1962 in the Mae Sariang District, Mae Hong Son Province. Since then, about 130 outbreaks have been reported involving 7392 patients and 97 deaths (1962-2005). The highest number of cases, 557, was recorded in 1983. The annual epidemiological surveillance reports of the Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health, Thailand, show that trichinosis cases increased from 61 in 1997 to 351 in 1998. In contrast to these figures, the number of reported cases decreased to 16 in 1999 and 128 cases in 2000. There was no record of trichinosis in 2001, but then the figures for 2002, 2003 and 2004 were 289, 126 and 212 respectively. The infected patients were mostly in the 35-44 years age group and the disease occurred more frequently in men than women at a ratio of 1.7-2.0:1. There were 84 reported cases of trichinosis in Chiang Rai, Nan, Chiang Mai, Si Sa ket, Nakhon Phanom, Kalasin, Nakhon Ratchasima, Nakhon Nayok, Nakhon Pathom and Surat Thani, provinces located in different parts of Thailand in 2005. The outbreaks were more common in the northern areas, especially in rural areas where people ate raw or under-cooked pork and/or wild animals. This indicates the need for health education programs to prevent and control trichinosis as soon as possible in the high-risk areas. PMID:17072975

  10. Culicoides spp. (Diptera: Ceratopogonidae) as vectors of bluetongue virus in South Africa - a review.

    PubMed

    Venter, Gert Johannes

    2015-01-01

    The aim of this paper is to consolidate vector competence studies on Culicoides midges (Diptera: Ceratopogonidae) as vectors of bluetongue virus (BTV) done over a period 25 years at the ARC‑Onderstepoort Veterinary Institute in South Africa. In 1944, it was demonstrated for the first time in South Africa that Culicoides midges transmit BTV. In 1991, field‑collected Culicoides imicola were fed on blood containing BTV‑3 or ‑6 and the infection rates were established as being 31% and 24%, respectively. In 1998, Culicoides bolitinos was shown to have a higher infection prevalence and virus titre/midge than C. imicola. This species was then shown to have a higher transmission potential for BTV‑1 over a range of incubation temperatures wider than the one showed by C. imicola. Attenuation of BTV also does not reduce its ability to infect competent Culicoides species. Oral susceptibility studies, involving 29 BTV isolates of various serotypes, indicated differences between various geographic virus isolates and Culicoides populations evaluated. While low recovery rates of European BTV strains from South African Culicoides species suggest co‑adaptation between orbiviruses and vectors in a given locality, co‑adaption was shown not to be essential for virus transmission. Cumulative results since 1991 provide evidence that at least 13 livestock‑associated Culicoides species are susceptible to BTV. Susceptibility results are supported by field isolations from 5 of these species. This implies that multi‑vector potential for the transmission of BTV will complicate the epidemiology of BT. It must be emphasised that neither oral susceptibility nor virus isolation/detection from field‑collected specimens is proof that a species is a confirmed field vector. PMID:26741247

  11. Atmospheric Chemistry Over Southern Africa

    NASA Technical Reports Server (NTRS)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2011-01-01

    During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semi-permanent atmosphere gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s, and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite-derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission for Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from the South African power utility, Eskom, and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa. The purpose of the workshop was to review some earlier findings as well as more recent findings on southern African climate vulnerability, chemical changes due to urbanization, land-use modification, and how these factors interact. Originally proposed by John Burrows, president of ICACGP, the workshop was the first ICACGP regional workshop to study the interaction of air pollution with global chemical and climate change. Organized locally by the University of the Witwatersrand, the workshop attracted more than 60 delegates from South Africa, Mozambique, Botswana, Zimbabwe, France, Germany, Canada, and the United States. More than 30 presentations were given, exploring both retrospective and prospective aspects of the science. In several talks, attention was focused on southern African chemistry, atmospheric pollution monitoring, and climate processes as they were studied in the field

  12. Epidemiologic research in Antarctica

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A study of epidemiology of respiratory viruses that was begun in the early 1960's is described. Locations selected for the study included a Wisconsin University housing village, a second grade school population, individual volunteers who associated socially, married couples, and the winter-over population at McMurdo Bay and at Scott Base in the Antarctic. It was concluded that most rhinovirus transmission is through aerosolized particles. Air filtration and careful nasal sanitation with virucidal tissues are determined to be effective in blocking rhinovirus transmission and should be useful in both isolated space colonies and in ordinary earth-bound populations.

  13. Migraine headache: epidemiologic perspectives.

    PubMed

    Linet, M S; Stewart, W F

    1984-01-01

    Clinical and epidemiologic studies suggest that a number of factors are associated with the risk of migraine and precipitation of an attack. However, the degree to which causal associations can be inferred from reported studies is very limited and is a result of the methodological problems discussed throughout this review. The study of migraine in many ways parallels the pattern seen in early investigations of other conditions, such as rheumatoid arthritis and systemic lupus erythematosus, because a number of methodological problems had to be resolved in the study of these conditions before significant progress could be made. To achieve significant advances in the improvement of our understanding of the causes of migraine, a number of related issues must be addressed and resolved in future studies. Most noteworthy among these are Recognition of the probable heterogeneity of migraine, not merely in the manifestation of symptoms but, more importantly, in the existence of distinct etiologic subtypes. A number of findings suggest that some migraine subtypes are sensitive to certain precipitants, some appear to be a part of a more generalized constitutional disorder, and some are accompanied by a higher prevalence of migraine among family members. Efforts should be made in understanding the relationship between specific biochemical markers and traits (such as monoamine oxidase deficiency and tyramine sensitivity); precipitants related to the migraine attack; and epidemiologic characteristics such as age at onset and sex. Creation of a more precise, reliable, and practically useful definition of migraine. Without such a definition, it is difficult, if not impossible, to compare results between studies, to understand the relationship between risk factors and migraine subtypes, to understand properly associations identified in selected clinic populations, and, in general, to understand the epidemiology of migraine. More accurate characterization of the case group under

  14. New Agricultural Settlement, Meheba River, Zambia, Africa

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This infra-red view of a new settlement along the Meheba River, Zambia, Africa (12.5S, 26.0E) resembles the resettlement clusters in the Amazon basin of Brazil. However, this settlement is on savanna land not a tropical forest region, so relatively little land clearing was required. The familiar pattern of small single family plots, no large commercial fields, along the branches of a herringbone road network is evident.

  15. Food and environmental policies in Africa.

    PubMed

    Biswas, M R; Biswas, A K

    1986-08-01

    Not only is Africa experiencing severe food production and nutrition problems, but environmental conditions, on which agricultural production ultimately depends, are deteriorating. A meeting of the African Ministers of Environment was held in Cairo last December, and an African solution to an African problem was put forth. The proposed program is examined in this paper. The usable extent of the pastoral area in the arid and semi-arid regions of Africa nas been reduced by 25% since 1968. At present only about 35% of the former area of slightly productive savannah is left. Africa's rich fishing grounds are being overfished and coastal regions are threatened by pollution. Africa's problems are linked with very high rates of population growth, rapid rates of urbanization, inappropriate development policies that have neglected the agricultural sector, and nonavailability of skilled manpower. The Cairo Program of African Cooperation included the following proposals: 8 continent-wide networks of institutions are to be established or strenghened in the fields of climatology, soils and fertilizers, water resources, energy, genetic resources, environmental monitoring, science and technology, and education and training; all available African skills and experience are to be applied to seek economically feasible, environmentally sound and socially acceptable solutions in certain regions; subregional cooperation is to be strenghened in terms of implementation of priority activities; 4 committees were established in areas of priority concerns; and a formula to provide US$32.5 million to finance the follow-up activities was approved.

  16. Genetic Epidemiology in Aging Research

    PubMed Central

    Matteini, Amy

    2009-01-01

    Over the last two decades, aging research has expanded to include not only age-related disease models, and conversely, longevity and disease-free models, but also focuses on biological mechanisms related to the aging process. By viewing aging on multiple research frontiers, we are rapidly expanding knowledge as a whole and mapping connections between biological processes and particular age-related diseases that emerge. This is perhaps most true in the field of genetics, where variation across individuals has improved our understanding of aging mechanisms, etiology of age-related disease, and prediction of therapeutic responses. A close partnership between gerontologists, epidemiologists, and geneticists is needed to take full advantage of emerging genome information and technology and bring about a new age for biological aging research. Here we review current genetic findings for aging across both disease-specific and aging process domains. We then highlight the limitations of most work to date in terms of study design, genomic information, and trait modeling and focus on emerging technology and future directions that can partner genetic epidemiology and aging research fields to best take advantage of the rapid discoveries in each. PMID:19168782

  17. Is there epidemiology in Russia?

    PubMed Central

    Vlassov, V.

    2000-01-01

    OBJECTIVE—To examine the current state of epidemiology in Russia.
DESIGN—The structure of clinical research and statistical methods was used to shed light on the epidemiology in Russia. The frequencies of specific study designs were evaluated using Medline data for 1970-1997. To determine the proportion of advanced design clinical studies the frequency of cohort, prospective, follow up, or longitudinal studies, and controlled trials was evaluated. All diagnosis related studies were found to determine the usage of advanced statistical technique (ROC analysis). The adequacy of Medline information was checked by hand search of journals. All dissertations in epidemiology defended in Russia in 1995 and 1996 were evaluated for their methodology. The curriculum recommended by Ministry of Health to Medical Universities was evaluated. Available literature and library indexing of epidemiological terms examined.
MAIN RESULTS—Russian medical research uses less frequently advanced study designs and methods of data analysis. Medical students are taught epidemiology as a science of spread of infectious diseases. There is no department of epidemiology in Russian universities where epidemiology is taught in the modern sense and no epidemiological and biostatistical periodicals available in Russia.
CONCLUSION—Epidemiology in Russia remains in an archaic state of science of the spread of infectious diseases and it is detrimental to methodology of medical research in Russia.


Keywords: Soviet Union; Russia; study design; comparative studies PMID:10990475

  18. The People's Library of Epidemiology.

    PubMed

    Last, John M

    2012-03-01

    The People's Library of Epidemiology is in the process of development. It consists of a website (http://www.jameslindlibrary.org) with links to online excerpts of papers and monographs of historical and scientific importance in epidemiology and related public health sciences that are held by the library of the Royal College of Physicians of Edinburgh. This paper reflects the lively panel discussion which took place on 9 August 2011. The panel members who opened the discussion were Alfredo Morabia, Anne Hardy, Roger Bernier, Jan Vandenbroucke, George Davey Smith, Esther Villalonga and Stephen Walter, who had won the prize awarded by Epidemiology Monitor for an essay on the People's Library of Epidemiology.

  19. Transforming Epidemiology for 21st Century Medicine and Public Health

    SciTech Connect

    Khoury, Muin J; Lam, Tram Kim; Ioannidis, John; Hartge, Patricia; Spitz, Margaret R.; Buring, Julie E.; Chanock, Stephen J.; Tourassi, Georgia; Zauber, Ann; Schully, Sheri D

    2013-01-01

    n 2012, the National Cancer Institute (NCI) engaged the scientific community to provide a vision for cancer epidemiology in the 21st century. Eight overarching thematic recommendations, with proposed corresponding actions for consideration by funding agencies, professional societies, and the research community emerged from the collective intellectual discourse. The themes are (i) extending the reach of epidemiology beyond discovery and etiologic research to include multilevel analysis, intervention evaluation, implementation, and outcomes research; (ii) transforming the practice of epidemiology by moving toward more access and sharing of protocols, data, metadata, and specimens to foster collaboration, to ensure reproducibility and replication, and accelerate translation; (iii) expanding cohort studies to collect exposure, clinical, and other information across the life course and examining multiple health-related endpoints; (iv) developing and validating reliable methods and technologies to quantify exposures and outcomes on a massive scale, and to assess concomitantly the role of multiple factors in complex diseases; (v) integrating big data science into the practice of epidemiology; (vi) expanding knowledge integration to drive research, policy, and practice; (vii) transforming training of 21st century epidemiologists to address interdisciplinary and translational research; and (viii) optimizing the use of resources and infrastructure for epidemiologic studies. These recommendations can transform cancer epidemiology and the field of epidemiology, in general, by enhancing transparency, interdisciplinary collaboration, and strategic applications of new technologies. They should lay a strong scientific foundation for accelerated translation of scientific discoveries into individual and population health benefits.

  20. Charting a Future for Epidemiologic Training

    PubMed Central

    Samet, Jonathan M.; Chavez, Gilbert F.; Davies, Megan M.; Galea, Sandro; Hiatt, Robert A.; Hornung, Carlton A.; Khoury, Muin J.; Koo, Denise; Mays, Vickie M.; Remington, Patrick; Yarber, Laura

    2015-01-01

    Purpose To identify macro level trends that are changing the needs of epidemiologic research and practice and to develop and disseminate a set of competencies and recommendations for epidemiologic training that will be responsive to these changing needs. Methods There were three stages to the project: 1) assembly of a working group of senior epidemiologists from multiple sectors, 2) Identifying relevant literature, and 3) conducting key informant interviews with 15 experienced epidemiologists. Results Twelve macro trends were identified along with associated actions for the field and educational competencies. The macro trends include: 1) “Big Data”/ informatics, 2) the changing health communication environment, 3) the Affordable Care Act/health care system reform, 4) shifting demographics, 5) globalization, 6) emerging high throughput technologies (“omics”), 7) a greater focus on accountability, 8) privacy changes, 9) a greater focus on “upstream” causes of disease, 10) the emergence of translational sciences, 11) the growing centrality of team and trans-disciplinary science, and 12) the evolving funding environment. Conclusion Addressing these issues through curricular change is needed to allow the field of epidemiology to more fully reach and sustain its full potential to benefit population health and remain a scientific discipline that makes critical contributions to ensuring clinical, social, and population health. PMID:25976024

  1. Rickettsia africae in Hyalomma dromedarii ticks from sub-Saharan Algeria.

    PubMed

    Kernif, Tahar; Djerbouh, Amel; Mediannikov, Oleg; Ayach, Bouhous; Rolain, Jean-Marc; Raoult, Didier; Parola, Philippe; Bitam, Idir

    2012-12-01

    Spotted fever group (SFG) rickettsioses are caused by obligate, intracellular Gram-negative bacteria of the genus Rickettsia. In recent years, several species and subspecies of rickettsias have been identified as emerging pathogens throughout the world, including sub-Saharan Africa. We report here the detection of Rickettsia africae, the agent responsible for African tick-bite fever, by amplification of fragments of gltA and ompA genes and multi-spacer typing from Hyalomma dromedarii ticks collected from the camel Camelus dromedarius in the Adrar and Béchar region (sub-Saharan Algeria). To date, R. africae has been associated mainly with Amblyomma spp. The role of H. dromedarii in the epidemiology of R. africae requires further investigation.

  2. Epidemiology of rickettsial diseases.

    PubMed

    Walker, D H; Fishbein, D B

    1991-05-01

    Rickettsial diseases have a diversity of epidemiologic characteristics reflective of the variety of ecologic situations in which the obligate intracellular bacteria are transmitted to humans. For the spotted fever group (SFG) rickettsiae, Rickettsia typhi, R. tsutsugamushi, Coxiella burnetii, and the human ehrlichial agent, humans are a dead-end host who plays no role in the maintenance of the organism in nature. All rickettsioses exist as zoonoses. Moreover, all rickettsiae are found in infected arthopods, which generally serve as the natural hosts and can transmit the infection to the next generation of ticks, mites, chiggers, or fleas. From our anthropocentric viewpoint, Q fever aerosol infection from parturient animals and Brill-Zinsser disease ignited epidemics of louse-borne epidemic typhus are exceptions. However, silent cycles of C. burnetii in ticks and R. prowazekii in the flying squirrel flea may have maintained these agents in transovarial or enzootic cycles for eons before humans and their domestic animals arrived on the scene. Thus, the epidemiology of rickettsial diseases must be recognized as an unfortunate aberration of the rickettsial economy. Several excellent reviews of rickettsial ecology contain a wealth of useful information. PMID:1884775

  3. The Epidemiology of Sarcopenia.

    PubMed

    Dodds, Richard Matthew; Roberts, Helen Clare; Cooper, Cyrus; Sayer, Avan Aihie

    2015-01-01

    The aim of this review is to describe the epidemiology of sarcopenia, specifically prevalence, health outcomes, and factors across the life course that have been linked to its development. Sarcopenia definitions involve a range of measures (muscle mass, strength, and physical performance), which tend to decline with age, and hence sarcopenia becomes increasingly prevalent with age. Less is known about prevalence in older people in hospital and care homes, although it is likely to be higher than in community settings. The range of measures used, and the cutpoints suggested for each, presents a challenge for comparing prevalence estimates between studies. The importance of sarcopenia is highlighted by the range of adverse health outcomes that strength and physical performance (and to a lesser extent, muscle mass) have been linked to. This is shown most strikingly by the finding of increased all-cause mortality rates among those with weaker grip strength and slower gait speed. A life course approach broadens the window for our understanding of the etiology of sarcopenia and hence the potential intervention. An example is physical activity, with increased levels across midadulthood appearing to increase muscle mass and strength in early old age. Epidemiologic studies will continue to make an important contribution to our understanding of sarcopenia and possible avenues for intervention and prevention.

  4. Molecular Epidemiology of Amebiasis

    PubMed Central

    Ali, Ibne Karim M.; Clark, C. Graham; Petri, William A.

    2008-01-01

    Entamoeba histolytica, the causative agent of human amebiasis, remains a significant cause of morbidity and mortality in developing countries and is responsible for up to 100,000 deaths worldwide each year. Entamoeba dispar, morphologically indistinguishable from E. histolytica, is more common in humans in many parts of the world. Similarly Entamoeba moshkovskii, which was long considered to be a free-living ameba, is also morphologically identical to E. histolytica and E. dispar, and is highly prevalent in some E. histolytica endemic countries. However, the only species to cause disease in humans is E. histolytica. Most old epidemiological data on E. histolytica are unusable as the techniques employed do not differentiate between the above three Entamoeba species. Molecular tools are now available not only to diagnose these species accurately but also to study intra-species genetic diversity. Recent studies suggest that only a minority of all E. histolytica infections progress to development of clinical symptoms in the host and there exist population level differences between the E. histolytica strains isolated from the asymptomatic and symptomatic individuals. Nevertheless the underlying factors responsible for variable clinical outcome of infection by E. histolytica remain largely unknown. We anticipate that the recently completed E. histolytica genome sequence and new molecular techniques will rapidly advance our understanding of the epidemiology and pathogenicity of amebiasis. PMID:18571478

  5. Epidemiology, austerity, and innovation.

    PubMed

    Samet, Jonathan M; Ness, Roberta B

    2012-05-15

    In considering the state of epidemiologic research, these are the "best" and the "worst" of times-the "best" from the perspective of scientific opportunities and the "worst" from the perspective of funding. In this commentary, the authors address this time of funding austerity from the points of view of individual researchers and research institutions. For researchers, the new tools of "-omics," large databases, communication by means of the World Wide Web, and global access offer ever-expanding scientific opportunities. The authors comment on research directions for which there is an enhanced likelihood of funding success: clinical and translational research, outcomes and effectiveness research, and global health research. The authors emphasize the need to be innovative and not bound by the conventional. For institutions, the authors suggest attention to innovation and impact, social networking, and finding the "right size" for training programs. Academic institutions also need to invest, supporting researchers and their ideas. Epidemiologists need to be true to their mission and prove that they can use innovation to advance health and welfare in a measurable way. Doing so will ensure that over the long term, epidemiologic research will remain a cornerstone for advancing population health.

  6. Ecogeographic Genetic Epidemiology

    PubMed Central

    Sloan, Chantel D.; Duell, Eric J.; Shi, Xun; Irwin, Rebecca; Andrew, Angeline S.; Williams, Scott M.; Moore, Jason H.

    2009-01-01

    Complex diseases such as cancer and heart disease result from interactions between an individual's genetics and environment, i.e. their human ecology. Rates of complex diseases have consistently demonstrated geographic patterns of incidence, or spatial “clusters” of increased incidence relative to the general population. Likewise, genetic subpopulations and environmental influences are not evenly distributed across space. Merging appropriate methods from genetic epidemiology, ecology and geography will provide a more complete understanding of the spatial interactions between genetics and environment that result in spatial patterning of disease rates. Geographic Information Systems (GIS), which are tools designed specifically for dealing with geographic data and performing spatial analyses to determine their relationship, are key to this kind of data integration. Here the authors introduce a new interdisciplinary paradigm, ecogeographic genetic epidemiology, which uses GIS and spatial statistical analyses to layer genetic subpopulation and environmental data with disease rates and thereby discern the complex gene-environment interactions which result in spatial patterns of incidence. PMID:19025788

  7. Global epidemiology of sporotrichosis.

    PubMed

    Chakrabarti, Arunaloke; Bonifaz, Alexandro; Gutierrez-Galhardo, Maria Clara; Mochizuki, Takashi; Li, Shanshan

    2015-01-01

    Sporotrichosis is an endemic mycosis caused by the dimorphic fungus Sporothrix schenckii sensu lato. It has gained importance in recent years due to its worldwide prevalence, recognition of multiple cryptic species within the originally described species, and its distinctive ecology, distribution, and epidemiology across the globe. In this review, we describe the current knowledge of the taxonomy, ecology, prevalence, molecular epidemiology, and outbreaks due to S. schenckii sensu lato. Despite its omnipresence in the environment, this fungus has remarkably diverse modes of infection and distribution patterns across the world. We have delved into the nuances of how sporotrichosis is intimately linked to different forms of human activities, habitats, lifestyles, and environmental and zoonotic interactions. The purpose of this review is to stimulate discussion about the peculiarities of this unique fungal pathogen and increase the awareness of clinicians and microbiologists, especially in regions of high endemicity, to its emergence and evolving presentations and to kindle further research into understanding the unorthodox mechanisms by which this fungus afflicts different human populations.

  8. Epidemiology of bronchioloalveolar carcinoma.

    PubMed

    Falk, R T; Pickle, L W; Fontham, E T; Greenberg, S D; Jacobs, H L; Correa, P; Fraumeni, J F

    1992-01-01

    Descriptive features of bronchioloalveolar carcinoma (BAC) are presented using Surveillance, Epidemiology and End Results Program population-based incidence data from 1973 through 1987, along with risk factors from histologically confirmed cases of BAC identified in a hospital-based case-control study conducted in Louisiana between 1979 and 1982. Compared to the rising incidence of lung cancer overall, BAC rates have remained relatively constant, accounting for less than 3% of all lung cancer. BAC incidence rates were higher in males, yet it explained proportionately more of the total lung cancer incidence in females. In the case-control study, 21 of the 33 cases originally ascertained from hospital pathology records were histologically confirmed as BAC. Most cases smoked cigarettes, with a 4-fold risk for ever smoking. Risks tended to increase with smoking intensity (reaching 10-fold for more than 1.5 packs/day) and duration (reaching 5-fold for more than 45 years of smoking). Following 10 or more years of employment, there was a 4-fold risk associated with motor freight occupations, along with nonsignificant excesses among construction workers, petroleum manufacturers, and sugar cane farmers. Cases were more likely than controls to have had emphysema or to have had a close family member with lung cancer. Although based on small numbers, this study suggests that BAC shares many of the epidemiological characteristics of lung adenocarcinoma.

  9. Epidemiology of Neuroendocrine Tumors.

    PubMed

    Fraenkel, Merav; Faggiano, Antongiulio; Valk, Gerlof D

    2015-01-01

    Formerly named carcinoids, neuroendocrine tumors originate from diffuse endocrine cells, can involve any part of the gastrointestinal tract, endocrine pancreas and bronchopulmonary (BP) tree, and have a wide range of malignant potential. This chapter summarizes the data available on the epidemiology of neuroendocrine neoplasia (NEN) from around the world, including the relative frequency according to organ of origin, annual incidence rates (IR) and trends in IR at the various anatomic sites, age and stage at presentation, racial and gender differences in IR and 5-year survival rates. Over time, changes have been made in the classification and registration of NEN, both in the same registry and across the globe, thus confounding the possibility to draw conclusions as to the true rise in IR of NEN that is observed all over the world. BP NEN has become the most common site in many western countries, while NEN of the rectum is more common in the Far East. In some countries, appendiceal NEN is the most common site in females. When compared to adenocarcinoma of the same location, the prognosis of NEN patients is better. Five-year survival rates are highest for NEN originating in the rectum and appendix, but lower in small intestinal and pancreatic NEN. Future research is needed to understand the contribution of genetic and environmental factors to NEN epidemiology. PMID:26303701

  10. 6) Epidemiology and Control of Guatemalan Onchocerciasis

    PubMed Central

    Takaoka, Hiroyuki; Suzuki, Takeshi

    2015-01-01

    Recent studies on the epidemiology and control of Guatemalan onchocerciasis, chiefly made by the Guatemala–Japan Cooperative Project on Onchocerciasis Research and Control, are reviewed. Epidemiological features of Guatemalan onchocerciasis are summarized as to characteristic altitudinal distribution of endemic areas, disease manifestation, vector taxonomy, biology and transmission dynamic of the disease. Extensive insecticide studies in the field and laboratory demonstrate that the characteristic situations of Guatemalan streams where Simulium ochraceum, the main vector of onchocerciasis, breeds require ingenious methods of larviciding. Finally, the feasibility of an area vector control is indicated by the successful control operation in the San Vicente Pacaya Pilot Area, in which a new fixed-dose larviciding method was applied. PMID:26744576

  11. Epidemiology today: Mitigating threats to an ecosystem.

    PubMed

    Kreiger, Nancy

    2016-01-01

    Ecosystems comprise all the living and non-living things in a particular area (e.g., rain forest, desert), which interact and maintain equilibrium. Loss of equilibrium (e.g., clear-cutting trees in a rain forest) can mean the decline of the ecosystem, unless it is able to adapt to the new circumstances. The term "knowledge ecosystem" describes an approach to managing knowledge in a particular field; the components of this system include the people, the technological skills and resources, and information or data. Epidemiology can be thought of as a knowledge ecosystem and, like ecological systems, its existence can be threatened, from both internal and external forces that may alter its equilibrium. This paper describes some threats to the epidemiology knowledge ecosystem, how these threats came about, and what responses we can make that may serve to mitigate those threats. PMID:27348106

  12. Epidemiological Criminology”: Coming Full Circle

    PubMed Central

    Lanier, Mark M.

    2009-01-01

    Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose “epidemiological criminology” as a bridging framework. PMID:19150901

  13. Twin Studies: A Unique Epidemiological Tool

    PubMed Central

    Sahu, Monalisha; Prasuna, Josyula G

    2016-01-01

    Twin studies are a special type of epidemiological studies designed to measure the contribution of genetics as opposed to the environment, to a given trait. Despite the facts that the classical twin studies are still being guided by assumptions made back in the 1920s and that the inherent limitation lies in the study design itself, the results suggested by earlier twin studies have often been confirmed by molecular genetic studies later. Use of twin registries and various innovative yet complex software packages such as the (SAS) and their extensions (e.g., SAS PROC GENMOD and SAS PROC PHREG) has increased the potential of this epidemiological tool toward contributing significantly to the field of genetics and other life sciences. PMID:27385869

  14. [Epidemiological examples of infectious disease spread].

    PubMed

    Schlüter, H; Kramer, M

    2001-08-01

    The globalisation of trade with animals and animal products and increase of travel transports are very important issues with respect to prevent and control animal diseases or epizootics respectively. The disease control concepts as a complex manner should be established on scientific basis and must be permanently evaluated and updated. Outbreak investigations in order to clarify the source of infection and/or the spread of animal diseases including zoonoses are important fields of activities of veterinary epidemiologists. The application of modern epidemiological methods is the precondition of a successful disease control. On selected examples of animal diseases, the use of these methods is demonstrated. It is urgently necessary to intensify the epidemiological work in applied research and practice.

  15. Rickettsia africae and Candidatus Rickettsia barbariae in Ticks in Israel

    PubMed Central

    Waner, Trevor; Keysary, Avi; Eremeeva, Marina E.; Din, Adi Beth; Mumcuoglu, Kosta Y.; King, Roni; Atiya-Nasagi, Yafit

    2014-01-01

    DNA of several spotted fever group rickettsiae was found in ticks in Israel. The findings include evidence for the existence of Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel. The DNA of R. africae was detected in a Hyalomma detritum tick from a wild boar and DNA of C. Rickettsia barbariae was detected in Rhipicephalus turanicus and Rhipicephalus sanguineus collected from vegetation. The DNA of Rickettsia massiliae was found in Rh. sanguineus and Haemaphysalis erinacei, whereas DNA of Rickettsia sibirica mongolitimonae was detected in a Rhipicephalus (Boophilus) annulatus. Clinicians should be aware that diseases caused by a variety of rickettsiae previously thought to be present only in other countries outside of the Middle East may infect residents of Israel who have not necessarily traveled overseas. Furthermore, this study reveals again that the epidemiology of the spotted fever group rickettsiae may not only involve Rickettsia conorii but may include other rickettsiae. PMID:24615133

  16. Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel.

    PubMed

    Waner, Trevor; Keysary, Avi; Eremeeva, Marina E; Din, Adi Beth; Mumcuoglu, Kosta Y; King, Roni; Atiya-Nasagi, Yafit

    2014-05-01

    DNA of several spotted fever group rickettsiae was found in ticks in Israel. The findings include evidence for the existence of Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel. The DNA of R. africae was detected in a Hyalomma detritum tick from a wild boar and DNA of C. Rickettsia barbariae was detected in Rhipicephalus turanicus and Rhipicephalus sanguineus collected from vegetation. The DNA of Rickettsia massiliae was found in Rh. sanguineus and Haemaphysalis erinacei, whereas DNA of Rickettsia sibirica mongolitimonae was detected in a Rhipicephalus (Boophilus) annulatus. Clinicians should be aware that diseases caused by a variety of rickettsiae previously thought to be present only in other countries outside of the Middle East may infect residents of Israel who have not necessarily traveled overseas. Furthermore, this study reveals again that the epidemiology of the spotted fever group rickettsiae may not only involve Rickettsia conorii but may include other rickettsiae.

  17. Pediatric trauma care in Africa: the evolution and challenges.

    PubMed

    Abdur-Rahman, Lukman O; van As, A B Sebastian; Rode, Heinz

    2012-05-01

    Childhood trauma is one of the major health problems in the world. Although pediatric trauma is a global phenomenon in low- and middle-income countries, sub-Saharan countries are disproportionally affected. We reviewed the available literature relevant to pediatric trauma in Africa using the MEDLINE database, local libraries, and personal contacts. A critical review of all cited sources was performed with an emphasis on the progress made over the past decades as well as the ongoing challenges in the prevention and management of childhood trauma. After discussing the epidemiology and spectrum of pediatric trauma, we focus on the way forward to reduce the burden of childhood injuries and improve the management and outcome of injured children in Africa.

  18. Deciphering the origin of the 2012 cholera epidemic in Guinea by integrating epidemiological and molecular analyses.

    PubMed

    Rebaudet, Stanislas; Mengel, Martin A; Koivogui, Lamine; Moore, Sandra; Mutreja, Ankur; Kande, Yacouba; Yattara, Ousmane; Sarr Keita, Véronique; Njanpop-Lafourcade, Berthe-Marie; Fournier, Pierre-Edouard; Garnotel, Eric; Keita, Sakoba; Piarroux, Renaud

    2014-06-01

    Cholera is typically considered endemic in West Africa, especially in the Republic of Guinea. However, a three-year lull period was observed from 2009 to 2011, before a new epidemic struck the country in 2012, which was officially responsible for 7,350 suspected cases and 133 deaths. To determine whether cholera re-emerged from the aquatic environment or was rather imported due to human migration, a comprehensive epidemiological and molecular survey was conducted. A spatiotemporal analysis of the national case databases established Kaback Island, located off the southern coast of Guinea, as the initial focus of the epidemic in early February. According to the field investigations, the index case was found to be a fisherman who had recently arrived from a coastal district of neighboring Sierra Leone, where a cholera outbreak had recently occurred. MLVA-based genotype mapping of 38 clinical Vibrio cholerae O1 El Tor isolates sampled throughout the epidemic demonstrated a progressive genetic diversification of the strains from a single genotype isolated on Kaback Island in February, which correlated with spatial epidemic spread. Whole-genome sequencing characterized this strain as an "atypical" El Tor variant. Furthermore, genome-wide SNP-based phylogeny analysis grouped the Guinean strain into a new clade of the third wave of the seventh pandemic, distinct from previously analyzed African strains and directly related to a Bangladeshi isolate. Overall, these results highly suggest that the Guinean 2012 epidemic was caused by a V. cholerae clone that was likely imported from Sierra Leone by an infected individual. These results indicate the importance of promoting the cross-border identification and surveillance of mobile and vulnerable populations, including fishermen, to prevent, detect and control future epidemics in the region. Comprehensive epidemiological investigations should be expanded to better understand cholera dynamics and improve disease control

  19. Commentary: Epidemiology in the era of big data.

    PubMed

    Mooney, Stephen J; Westreich, Daniel J; El-Sayed, Abdulrahman M

    2015-05-01

    Big Data has increasingly been promoted as a revolutionary development in the future of science, including epidemiology. However, the definition and implications of Big Data for epidemiology remain unclear. We here provide a working definition of Big Data predicated on the so-called "three V's": variety, volume, and velocity. From this definition, we argue that Big Data has evolutionary and revolutionary implications for identifying and intervening on the determinants of population health. We suggest that as more sources of diverse data become publicly available, the ability to combine and refine these data to yield valid answers to epidemiologic questions will be invaluable. We conclude that while epidemiology as practiced today will continue to be practiced in the Big Data future, a component of our field's future value lies in integrating subject matter knowledge with increased technical savvy. Our training programs and our visions for future public health interventions should reflect this future.

  20. Internet Performance to Africa

    SciTech Connect

    Cottrell, L

    2003-10-01

    We report the first results ever for real-time Internet performance to Africa using the PingER methodology. Multiple monitoring hosts were used to enable comparisons with performance from different parts of the world. From these preliminary measurements, we have found that Internet packet losses to some African sites in recent months range from very poor to bad (> 12%), some getting better, others are holding steady or getting worse. This, together with the average monthly Round Trip Times, imply end-to-end maximum TCP throughputs that are order of magnitudes different between countries in the region. Africa is shown to be far from the Internet performance in industrialized nations due to the poor infrastructure in place today. These monitoring efforts can provide valuable information to analyze the relative rates of future improvement and today they help us to quantify the digital divide and can provide quantitative information to policy makers.

  1. This Is Africa.

    PubMed

    Verlo, April R; Bailey, Hugh H; Cook, Martin R

    2015-01-01

    Military deployments will always result in exposure to health hazards other than those from combat operations. The occupational and environmental health and endemic disease health risks are greater to the Special Operations Forces (SOF) deployed to the challenging conditions in Africa than elsewhere in the world. SOF are deployed to locations that lack life support infrastructures that have become standard for most military deployments; instead, they rely on local resources to sustain operations. Particularly, SOF in Africa do not generally have access to advanced diagnostic or monitoring capabilities or to medical treatment in austere locations that lack environmental or public health regulation. The keys to managing potential adverse health effects lie in identifying and documenting the health hazards and exposures, characterizing the associated risks, and communicating the risks to commanders, deployed personnel, and operational planners.

  2. The ethical design of an AIDS vaccine trial in Africa.

    PubMed

    Christakis, N A

    1988-01-01

    In 1987 in Zaire, a French investigator and a small group of Zairians were immunized with a French investigational AIDS vaccine. This action leads to questioning whether different sociocultural settings should have different research ethics applied, especially on pandemic diseases. Another question is to clarify the valid reasons for conducting an AIDS trial in Africa. The design of an AIDS vaccine trial should vary with the ethical and cultural factors of the research population involved, even if the epidemiological and scientific factors are the same worldwide. In Africa, study subjects meet the requirements for AIDS research: They are free from HIV infection and are at risk for the infection. However, concerns center on how to keep the subjects free from risks during the 6 months between HIV tests and how to ensure laboratory test accuracy. The applicability of the findings to that population are essential, although they may be unique to Africa. Research subjects must consent to participating in the trial and must be advised of their antibody status and of their becoming seropositive. To increase the beneficent treatment of subjects and decrease the risks, the study size should be increased and all participants should be counseled to avoid risky behaviors. A subject's family or social group may need to give consent in addition to the subject, because of cultural views. The explanation of the research must be in culturally relevant terms. Africa should have fair access to the vaccine resulting from the research. PMID:3397278

  3. Epidemiology of violent deaths in the world

    PubMed Central

    Reza, A; Mercy, J; Krug, E

    2001-01-01

    Objective—This study describes epidemiologic patterns of mortality due to suicide, homicide, and war for the world in order to serve as a benchmark against which to measure future progress and to raise awareness about violence as a global public health problem. Setting—The world and its eight major regions. Method—Data were derived from The Global Burden of Disease series and the US National Center for Health Statistics to estimate crude rates, age adjusted rates, sex rate ratios, and the health burden for suicide, homicide, and war related deaths for the world and its eight major regions in 1990. Results—In 1990, an estimated 1 851 000 people died from violence (35.3 per 100 000) in the world. There were an estimated 786 000 suicides. Overall suicide rates ranged from 3.4 per 100 000 in Sub-Saharan Africa to 30.4 per 100 000 in China. There were an estimated 563 000 homicides. Overall homicide rates ranged from 1.0 per 100 000 in established market economies to 44.8 per 100 000 in Sub-Saharan Africa with peaks among males aged 15–24 years old, and among females aged 0–4 years old. There were an estimated 502 000 war related deaths with peaks in rates for both sexes among people aged 0–4, 15–29, and 60–69 years old. Conclusion—The number of violence related deaths in the world is unacceptably high. Coordinated prevention and control efforts are urgently needed. PMID:11428556

  4. CEDR: Comprehensive Epidemiologic Data Resource

    SciTech Connect

    Not Available

    1993-08-01

    The Department of Energy (DOE) and its predecessor agencies have a long history of epidemiologic research programs. The main focus of these programs has been the Health and Mortality Study of the DOE work force. This epidemiologic study began in 1964 with a feasibility study of workers at the Hanford facility. Studies of other populations exposed to radiation have also been supported, including the classic epidemiologic study of radium dial painters and studies of atomic bomb survivors. From a scientific perspective, these epidemiologic research program have been productive, highly credible, and formed the bases for many radiological protection standards. Recently, there has been concern that, although research results were available, the data on which these results were based were not easily obtained by interested investigators outside DOE. Therefore, as part of an effort to integrate and broaden access to its epidemiologic information, the DOE has developed the Comprehensive Epidemiologic Data Resource (CEDR) Program. Included in this effort is the development of a computer information system for accessing the collection of CEDR data and its related descriptive information. The epidemiologic data currently available through the CEDAR Program consist of analytic data sets, working data sets, and their associated documentation files. In general, data sets are the result of epidemiologic studies that have been conducted on various groups of workers at different DOE facilities during the past 30 years.

  5. Terrorism in South Africa.

    PubMed

    MacFarlane, Campbell

    2003-01-01

    The Republic of South Africa lies at the southern tip of the African continent. The population encompasses a variety of races, ethnic groups, religions, and cultural identities. The country has had a turbulent history from early tribal conflicts, colonialisation, the apartheid period, and post-apartheid readjustment. Modern terrorism developed mainly during the apartheid period, both by activities of the state and by the liberation movements that continued to the time of the first democratic elections in 1994, which saw South Africa evolve into a fully representative democratic state with equal rights for all. Since 1994, terrorist acts have been criminal-based, evolving in the Cape Town area to political acts, largely laid at the feet of a predominantly Muslim organisation, People against Gangsterism and Drugs, a vigilant organisation allegedly infiltrated by Muslim fundamentalists. Along with this, has been terrorist activities, mainly bombings by disaffected members of white, right-wing groups. In the apartheid era, a Draconian series of laws was enacted to suppress liberation activities. After 1994, most of these were repealed and new legislation was enacted, particularly after the events of 11 September 2001; this legislation allows the government to act against terrorism within the constraints of a democratic system. Disaster management in South Africa has been largely local authority-based, with input from provincial authorities and Civil Defence. After 1994, attempts were made to improve this situation, and national direction was provided. After 11 September 2001, activity was increased and the Disaster Management Act 2002 was brought into effect. This standardized disaster management system at national, provincial, and local levels, also facilites risk assessment and limitation as well as disaster mitigation. The potential still exists for terrorism, mainly from right-wing and Muslim fundamentalist groups, but the new legislation should stimulate disaster

  6. Mozambique Coast, Africa

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The serene coastline of Mozambique (17.0S, 39.5E) Africa and the Indian Ocean offer some of the best beaches and recreational diving water in the world. Offshore reefs provide interesting coral formations that host a wide variety of marine life. Inland, the coastal savannas of this tropical nation are filled with a wide range of wildlife in some of the last animal refuges on the African continent.

  7. Lake Chad, Chad, Africa

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The fluctuating water levels of Lake Chad, (13.0N, 15.0E) at the intersection of the borders of Chad, Niger and Cameroon in the Sahara Desert, is an index of the drought in Africa. The lake level continues to decrease as indicated by the growing number and extent of emerging islands as previously submerged ancient sand dunes become visible. The water impounded between the dunes is probably because of local rainfall rather than a reversal of desertification.

  8. Marketing of irradiated commodities in South Africa

    NASA Astrophysics Data System (ADS)

    Du Plessis, TA; Stevens, RCB

    Although the industrial exploitation of radiation processing in the medical and allied fields has been successfully marketed and applied for the past two decades in South Africa, the introduction of food radurisation on an industrial level adds a completely new dimension to the marketing of this processing technique. Extensive research into the use of radiation for the treatment of various foodstuffs has been carried out by the Nuclear Development Corporation of South Africa for more than a decade, resulting in South Africa being one of the first countries where a commercial irradiator dedicated to this branch of radiation processing, was established. The marketing of this process is especially difficult due to the emotive aspects associated with radiation and man's sensitive reaction to anything pertaining to his food. This situation was made even more difficult by the general public's apprehension towards nuclear activities throughout the world. In an attempt to transform the unfavourable public image associated with this process, an important first step was to form a National Steering Committee for the Marketing of Radurised Food, the members of which were drawn from various agricultural controlling bodies, the Department of Health, and other controlling bodies held in high esteem by the public, such as the Consumer Council and representatives from commerce and industry. This approach proved to be very successful and greatly assisted in creating a climate whereby the public in South Africa today generally has a favourable attitude towards the radurisation of foodstuffs. The development of this marketing strategy for food radurisation in South Africa is discussed in detail.

  9. Counting apples as oranges: epidemiology and ethnography in adolescent substance abuse treatment.

    PubMed

    Reisinger, Heather Schacht

    2004-02-01

    In spite of a history of collaboration between epidemiology and qualitative research, the mix of these two perspectives is not well developed in the substance use field. Part of the reason for the difficult match is that qualitative research often adds issues of context and meaning that complicate the epidemiological data of interest. In the substance use field, epidemiological indicators tend to focus on a single drug, but the context typically involves persons who use multiple illicit and licit substances in a variety of ways that change over time. In this article, the author describes four adolescents in an outpatient substance abuse treatment center to provide context and insight into the lives behind the epidemiological indicators. Studying a site of epidemiological data collection ethnographically is yet another way to build collaboration between epidemiology and qualitative research. PMID:14768460

  10. Drought in West Africa

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Drought settled over West Africa's Ivory Coast region when wet season rains came late in 2007. Instead of beginning in February, the rainy season didn't start until March, and steady rains didn't start until late March, said the Famine Early Warning System Network. Though the rain had started to alleviate the drought, vegetation was still depressed in parts of Cote d'Ivoire (Ivory Coast) between March 22 and April 6, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured the data used to make this image. The image shows current vegetation conditions compared to average conditions recorded since 2000. Areas where plants are growing more slowly or more sparsely than average are brown, while areas where vegetation is denser than average are green. The brown tint that dominates the image indicates that plants through most of the country are more sparse than normal. Among the crops affected by the lack of rain was West Africa's cocoa crop. About 70 percent of the world's cocoa comes from West Africa, and Cote d'Ivoire is a top grower, said Reuters. Cocoa prices climbed as the crop fell short. Farmers called the drought the worst in living memory, Reuters said. The delay in rainfall also led to water shortages in parts of Cote d'Ivoire, according to the United Nations Office for the Coordination of Humanitarian Affairs.

  11. Hepatitis E: Epidemiology and Natural History

    PubMed Central

    Aggarwal, Rakesh

    2013-01-01

    Hepatitis E is a disease caused by infection with hepatitis E virus (HEV). The virus has four genotypes, named 1 to 4, with one shared serotype. Genotypes 1 and 2 infect only humans, whereas genotypes 3 and 4 primarily infect several mammalian animals, with occasional transmission to humans. Evidence of infection with HEV has been found in most parts of the world, with two distinct epidemiological patterns. In areas with high disease endemicity, primarily developing countries in Asia and Africa, the disease occurs as outbreaks and as sporadic cases of acute hepatitis, and is caused exclusively by infection with genotypes 1 or 2 HEV, which is acquired through fecal-oral route, usually through contamination of water supplies. The disease in these areas occurs most commonly in young adults, and is particularly severe in pregnant women and persons with pre-existing chronic liver disease; chronic infection has not been reported. In areas with lower endemicity, which are mainly developed areas with robust water supply and sanitation systems, occasional sporadic cases of locally-acquired genotype 3 or 4 HEV infection are observed. The affected persons are often elderly and have other coexisting illnesses. The reservoir of infection in these areas is believed to be in animals, such as pigs, wild boar and deer, with zoonotic transmission to humans, possibly through consumption of undercooked meat. Also, in these areas, persistent HEV infection has been well documented among immunosuppressed persons such as organ transplant recipients, and is believed to lead to chronic liver injury, including liver cirrhosis. Further work is needed to better understand the biological basis underlying these widely-differing epidemiological patterns. PMID:25755486

  12. The Epidemiology and Demographics of Hip Dysplasia

    PubMed Central

    Loder, Randall T.; Skopelja, Elaine N.

    2011-01-01

    The etiology of developmental dysplasia of the hip (DDH) is unknown. There are many insights, however, from epidemiologic/demographic information. A systematic medical literature review regarding DDH was performed. There is a predominance of left-sided (64.0%) and unilateral disease (63.4%). The incidence per 1000 live births ranges from 0.06 in Africans in Africa to 76.1 in Native Americans. There is significant variability in incidence within each racial group by geographic location. The incidence of clinical neonatal hip instability at birth ranges from 0.4 in Africans to 61.7 in Polish Caucasians. Predictors of DDH are breech presentation, positive family history, and gender (female). Children born premature, with low birth weights, or to multifetal pregnancies are somewhat protected from DDH. Certain HLA A, B, and D types demonstrate an increase in DDH. Chromosome 17q21 is strongly associated with DDH. Ligamentous laxity and abnormalities in collagen metabolism, estrogen metabolism, and pregnancy-associated pelvic instability are well-described associations with DDH. Many studies demonstrate an increase of DDH in the winter, both in the northern and southern hemispheres. Swaddling is strongly associated with DDH. Amniocentesis, premature labor, and massive radiation exposure may increase the risk of DDH. Associated conditions are congenital muscular torticollis and congenital foot deformities. The opposite hip is frequently abnormal when using rigorous radiographic assessments. The role of acetabular dysplasia and adult hip osteoarthritis is complex. Archeological studies demonstrate that the epidemiology of DDH may be changing. PMID:24977057

  13. Epidemiological evidence in forensic pharmacovigilance.

    PubMed

    Persaud, Nav; Healy, David

    2012-01-01

    Until recently epidemiological evidence was not regarded as helpful in determining cause and effect. It generated associations that then had to be explained in terms of bio-mechanisms and applied to individual patients. A series of legal cases surrounding possible birth defects triggered by doxylamine (Bendectin) and connective tissue disorders linked to breast implants made it clear that in some instances epidemiological evidence might have a more important role, but the pendulum swung too far so that epidemiological evidence has in recent decades been given an unwarranted primacy, partly perhaps because it suits the interests of certain stakeholders. Older and more recent epidemiological studies on doxylamine and other antihistamines are reviewed to bring out the ambiguities and pitfalls of an undue reliance on epidemiological studies.

  14. Emissions from savanna fires in southern Africa

    NASA Astrophysics Data System (ADS)

    Sinha, Parikhit

    2004-12-01

    Airborne measurements are presented of emissions from savanna fires in southern Africa during the dry season. Measurements were obtained aboard the University of Washington Convair-580 research aircraft during the SAFARI 2000 field project in August and September 2000. Savanna fires in southern Africa emit a wide range of gaseous and particulate species including carbon, sulfur, nitrogen, halogen, and oxygenated compounds. Emission factors, emission ratios, and regional emissions of fifty trace gas and particulate species were derived, including eight species not previously reported in the literature (dimethyl sulfide, methyl nitrate, five species of hydrocarbons, and particles with diameters from 0.1--3 mum diameter). The physical, chemical, and radiative properties of the plume from a large savanna fire in South Africa are characterized, including plume dimensions, secondary formation of ozone and organic acids, oxidation of hydrocarbons, coagulation of particles, and gas-to-particle conversion in aged smoke. Numerous fires, thermodynamically stable layers aloft, and large-scale anticylonic flow result in high concentrations of air pollution distributed throughout the lower troposphere over southern Africa during the dry season. Average regional concentrations of CO (261 +/- 81 ppbv), SO2 (2.5 +/- 1.6 ppbv), O3 (64 +/- 13 ppbv), black particulate carbon (2.3 +/- 1.9 mug m-3), organic particulate carbon (6.2 +/- 5.2 mug m-3), total particle mass (26.0 +/- 4.7 mug m-3) are comparable to those found in polluted urban environments. The GEOS-CHEM model of tropospheric chemistry is used to characterize the transport of biomass burning emissions from southern Africa to the neighboring Atlantic and Indian Oceans during the dry season (May--October) of 2000. A large quantity of biomass burning emissions from southern Africa is transported westward over the latitudes 0--20°S to the southern Atlantic Ocean (˜40 Tg CO from May--October), contributing to a pollution anomaly

  15. Spatial phylodynamics of HIV-1 epidemic emergence in east Africa

    PubMed Central

    Gray, Rebecca R.; Tatem, Andrew J.; Lamers, Susanna; Hou, Wei; Laeyendecker, Oliver; Serwadda, David; Sewankambo, Nelson; Gray, Ronald H.; Wawer, Maria; Quinn, Thomas C.; Goodenow, Maureen M.; Salemi, Marco

    2009-01-01

    Design We sought to investigate the evolutionary and historical reasons for the different epidemiological patterns of HIV-1 in the early epidemic. In order to characterize the demographic history of HIV-1 subtypes A and D in east Africa, we examined molecular epidemiology, geographical and historical data. Methodology We employed high-resolution phylodynamics to investigate the introduction of HIV-1A and D into east Africa, the geographic trends of viral spread, and the demographic growth of each subtype. We also used geographic information system data to investigate human migration trends, population growth, and human mobility. Results HIV-1A and D were introduced into east Africa after 1950 and spread exponentially during the 1970s, concurrent with eastward expansion. Spatiotemporal data failed to explain the establishment and spread of HIV based on urban population growth and migration. The low prevalence of the virus in the Democratic Republic of Congo before and after the emergence of the pandemic was, however, consistent with regional accessibility data, highlighting the difficulty in travel between major population centers in central Africa. In contrast, the strong interconnectivity between population centers across the east African region since colonial times has likely fostered the rapid growth of the epidemic in this locale. Conclusion This study illustrates how phylodynamic analysis of pathogens informed by geospatial data can provide a more holistic and evidence-based interpretation of past epidemics. We advocate that this ‘landscape phylodynamics’ approach has the potential to provide a framework both to understand epidemics' spread and to design optimal intervention strategies. PMID:19644346

  16. Sickle Cell Disease in Sub-Saharan Africa.

    PubMed

    Williams, Thomas N

    2016-04-01

    In Africa, at least 240,000 children are born each year with sickle cell disease. Historically, in the absence of newborn screening and appropriate treatment, most such children died undiagnosed in early childhood. However, with increasing awareness of the condition and economic and epidemiologic transition, increasing numbers are surviving. Greater investments in basic and applied research in the African context, and increased sensitization or African ministries of health regarding the importance of this condition, could make a substantial difference to the lives and livelihoods of millions of people living with sickle cell disease on the continent and their families.

  17. Developing expertise in bioinformatics for biomedical research in Africa

    PubMed Central

    Karikari, Thomas K.; Quansah, Emmanuel; Mohamed, Wael M.Y.

    2015-01-01

    Research in bioinformatics has a central role in helping to advance biomedical research. However, its introduction to Africa has been met with some challenges (such as inadequate infrastructure, training opportunities, research funding, human resources, biorepositories and databases) that have contributed to the slow pace of development in this field across the continent. Fortunately, recent improvements in areas such as research funding, infrastructural support and capacity building are helping to develop bioinformatics into an important discipline in Africa. These contributions are leading to the establishment of world-class research facilities, biorepositories, training programmes, scientific networks and funding schemes to improve studies into disease and health in Africa. With increased contribution from all stakeholders, these developments could be further enhanced. Here, we discuss how the recent developments are contributing to the advancement of bioinformatics in Africa. PMID:26767162

  18. Filovirus Research in Gabon and Equatorial Africa: The Experience of a Research Center in the Heart of Africa

    PubMed Central

    Leroy, Eric; Gonzalez, Jean Paul

    2012-01-01

    Health research programs targeting the population of Gabon and Equatorial Africa at the International Center for Medical Research in Franceville (CIRMF), Gabon, have evolved during the years since its inception in 1979 in accordance with emerging diseases. Since the reemergence of Ebola virus in Central Africa, the CIRMF “Emerging Viral Disease Unit” developed diagnostic tools and epidemiologic strategies and transfers of such technology to support the response of the National Public Health System and the World Health Organization to epidemics of Ebola virus disease. The Unit carries out a unique investigation program on the natural history of the filoviruses, emergence of epidemics, and Ebola virus pathogenesis. In addition, academic training is provided at all levels to regional and international students covering emerging conditions (host factors, molecular biology, genetics) that favor the spread of viral diseases. PMID:23170174

  19. [Epidemiological problems of obesity].

    PubMed

    Beiul, E A; Oleneva, V A; Mühr, M; Heller, G M; Popova, Iu P

    1980-01-01

    The results of epidemiological survey of the population living in the middle zone of the Soviet Union and in the GDR are considered. Comparison of the data obtained shows that overweight is a very prevalent abnormal condition among the test population groups in both countries and amounts to 26% (USSR) and 30% (GDR). Excess animal fat consumption in the presence of a decreased quota of vegetable oil has been established and a significant increase in monosaccharides intake noted. Attention is attracted by insufficient quota of fresh vegetables and fruit in the diets of the population of both countries. Qualitative and quantitative nutritional pitfalls were shown to be aggravated in obese people. Violation of dietetic regimens and decreased physical activity play a definite role in the development of overweight. A program on primary and secondary prevention of overweight has been established. It includes a number of measures both common and specific to the GDR and the USSR.

  20. Melanoma Epidemiology and Prevention.

    PubMed

    Berwick, Marianne; Buller, David B; Cust, Anne; Gallagher, Richard; Lee, Tim K; Meyskens, Frank; Pandey, Shaily; Thomas, Nancy E; Veierød, Marit B; Ward, Sarah

    2016-01-01

    The epidemiology of melanoma is complex, and individual risk depends on sun exposure, host factors, and genetic factors, and in their interactions as well. Sun exposure can be classified as intermittent, chronic, or cumulative (overall) exposure, and each appears to have a different effect on type of melanoma. Other environmental factors, such as chemical exposures-either through occupation, atmosphere, or food-may increase risk for melanoma, and this area warrants further study. Host factors that are well known to be important are the numbers and types of nevi and the skin phenotype. Genetic factors are classified as high-penetrant genes, moderate-risk genes, or low-risk genetic polymorphisms. Subtypes of tumors, such as BRAF-mutated tumors, have different risk factors as well as different therapies. Prevention of melanoma has been attempted using various strategies in specific subpopulations, but to date optimal interventions to reduce incidence have not emerged. PMID:26601858

  1. Cancer epidemiology of woodworking.

    PubMed

    Mohtashamipur, E; Norpoth, K; Lühmann, F

    1989-01-01

    The literature published between 1965 and 1989 on the cancer epidemiology of woodworking in furniture industries and carpentry shops in 17 countries is reviewed. Included are some unpublished data obtained through personal communication with epidemiologists or collected from doctoral dissertations. Of 5,785 cases with sino-nasal cancers, about 23% were found to be woodworkers. Dusty jobs, especially wood processing using high-speed machines, are mainly associated with the enhanced incidence of nasal adenocarcinomas. The latency periods of the latter tumors ranged from 7 to 69 years in five European countries. A variety of neoplasias of the respiratory, digestive, and urinary tracts as well as the hemopoietic and lymphatic systems, including Hodgkin's disease are reported to be significantly associated with occupational exposure to wood dust. These data suggest that the exposure to some types of wood dust might cause a systemic rather than local neoplastic disorder.

  2. EPIDEMIOLOGY OF PARACOCCIDIOIDOMYCOSIS

    PubMed Central

    MARTINEZ, Roberto

    2015-01-01

    SUMMARY The epidemiological characteristics of paracoccidioidomycosis were reviewed and updated. The new endemic areas in Brazil were discussed in the section regarding the geographic distribution of the mycosis. Subclinical infection with Paracoccidioides brasiliensis was discussed on the basis of skin test surveys with antigens of the fungus, seroepidemiological studies, and disease cases outside Latin America. Large case series permitted a comparison of the prevalence of the mycosis in different regions, its estimated incidence and risk factors for the development of the disease. Aspects modulating the expression of the clinical forms of paracoccidioidomycosis are also presented. This review also deals with diseases associated with the mycosis, opportunistic paracoccidioidomycosis, lethality, mortality and infection and disease in animals. PMID:26465364

  3. Epidemiology of HCV infection.

    PubMed

    Baldo, V; Baldovin, T; Trivello, R; Floreani, A

    2008-01-01

    It is estimated that approximately 130-170 million people worldwide are infected with hepatitis C virus (HCV). According to data from WHO community and blood donor surveys, the African and Eastern Mediterranean countries report the highest prevalence rates (>10%). The rates of infection in the general population and the incidence of newly-acquired cases indicate an appreciable change in the epidemiology of the infection in recent years. Prior to the widespread screening of blood donations, infected blood and blood products represented a common source of infection. On the other hand, the high peak in HCV antibodies among the elderly in Italian epidemiological studies on the population at large reflects a cohort effect due to an epidemic of HCV infection occurring after the Second World War. According to data reported by the CDC Surveillance System, the incidence of acute hepatitis C has declined since the late 1980s. In 2005, as in previous years, the majority of such cases in North America and Northern Europe occurred among young adults and injected drug use was the most common risk factor. Other, less commonly reported modes of HCV acquisition are occupational exposure to blood, high-risk sexual activity, tattooing, body piercing and other forms of skin penetration. Finally, the overall rate of mother-to-child transmission from HCV-infected, HIV-negative mothers has been estimated at around 5% (coinfection with HIV raises this figure to 19.4%). HCV prevention relies on identifying and counseling uninfected persons at risk of contracting hepatitis C. PMID:18673187

  4. Epidemiology of acne vulgaris.

    PubMed

    Bhate, K; Williams, H C

    2013-03-01

    Despite acne being an almost universal condition in younger people, relatively little is known about its epidemiology. We sought to review what is known about the distribution and causes of acne by conducting a systematic review of relevant epidemiological studies. We searched Medline and Embase to the end of November 2011. The role of Propionibacterium acnes in pathogenesis is unclear: antibiotics have a direct antimicrobial as well as an anti-inflammatory effect. Moderate-to-severe acne affects around 20% of young people and severity correlates with pubertal maturity. Acne may be presenting at a younger age because of earlier puberty. It is unclear if ethnicity is truly associated with acne. Black individuals are more prone to postinflammatory hyperpigmentation and specific subtypes such as 'pomade acne'. Acne persists into the 20s and 30s in around 64% and 43% of individuals, respectively. The heritability of acne is almost 80% in first-degree relatives. Acne occurs earlier and is more severe in those with a positive family history. Suicidal ideation is more common in those with severe compared with mild acne. In the U.S.A., the cost of acne is over 3 billion dollars per year in terms of treatment and loss of productivity. A systematic review in 2005 found no clear evidence of dietary components increasing acne risk. One small randomized controlled trial showed that low glycaemic index (GI) diets can lower acne severity. A possible association between dairy food intake and acne requires closer scrutiny. Natural sunlight or poor hygiene are not associated. The association between smoking and acne is probably due to confounding. Validated core outcomes in future studies will help in combining future evidence.

  5. Epidemiology of dental caries.

    PubMed

    Winter, G B

    1990-01-01

    The most recent epidemiological data on the prevalence of dental caries in children indicate a halting of the increasing levels in many developing countries and a continuing decrease in many highly industrialized countries of the world. However, a further fall in caries levels predicted for 5-yr-old children in the U.K. has not occurred and the decline in caries may have begun to level out. 'Polarization' of caries to a minority of high-risk individuals is occurring in the developed world, with 20-25% of children accounting for more than 50% of the disease. Socio-economic factors are important in determining the proportion of high-risk children in these countries. The multifactorial aetiology of caries allows a number of different interpretations to account for changes in the prevalence of the disease with time, in both the developing and developed countries. These changes are variously ascribed to alterations in dietary habits, especially the consumption of sugar; variations in the patterns of oral hygiene; increased contact with trace elements, especially fluoride, in the environment; changes in the ecology and/or virulence of oral and dental plaque microflora and alterations in the oral protective mechanisms including the immune status. The epidemiological evidence available on the relationship of all these social, environmental and other factors to changes in the prevalence levels of caries does not, however, fully explain all the changes that have been observed. The claim that caries is no longer a public health problem is premature, as it ignores the still high proportion of individuals with tooth decay throughout the world.

  6. Rabies in southern Africa.

    PubMed

    Swanepoel, R; Barnard, B J; Meredith, C D; Bishop, G C; Brückner, G K; Foggin, C M; Hübschle, O J

    1993-12-01

    The first confirmed outbreak of rabies in Africa, believed to have followed the importation of an infected dog from England in 1892, occurred in the eastern Cape Province of South Africa, and was brought under control in 1894. An unconfirmed epidemic of rabies in dogs occurred in western Zambia in 1901. By the following year the disease had apparently spread along a major trade route, to cause an outbreak in Zimbabwe which engulfed most of the country before being eradicated in 1913. The existence of endemic rabies of viverrids (mongooses and genets) was confirmed in South Africa in 1928, and since then the viverrid disease has continued to occur widely on the interior plateau of the country with spill-over of infection to cattle and a variety of other animals. From about 1947 onwards, an invasive form of dog rabies spread from southern Zambia and/or Angola into Namibia, across northern and eastern Botswana into Zimbabwe and the northern Transvaal by 1950, entered Mozambique in 1952, and spread from there to Swaziland in 1954. Dog rabies extended from southern Mozambique into Natal in 1961 to cause a major epidemic which was brought under control in 1968. The disease re-entered northern Natal from Mozambique in 1976 and since then dog rabies has proved difficult to control in the peri-urban settlements of Natal-KwaZulu. The disease spread from Natal to Lesotho in 1982, and into the Transkei region of the eastern Cape Province in 1987, to reach the Ciskei by 1990. The spread of the disease in dogs was followed by the emergence of rabies of jackals and cattle in central Namibia, northern Botswana, Zimbabwe and the northern Transvaal. A unique outbreak of rabies in kudu antelope occurred in central Namibia from 1977 to 1985, apparently involving oral spread of infection between individuals. A few cases of rabies in the bat-eared fox were recognized each year in Namibia from 1967 onwards, and from the 1970s the occurrence of the disease in the fox has emerged as a

  7. Satellite Magnetic Anomalies of Africa and Europe

    NASA Technical Reports Server (NTRS)

    Hinze, W. J.; Vonfrese, R. R. B. (Principal Investigator); Olivier, R.

    1984-01-01

    Preliminary MAGSAT scalar magnetic anomaly data of Africa, Europe, and adjacent marine areas were reduced to the pole assuming a constant inducing Earth's magnetic field of 60,000 nT. This process leads to a consistent anomaly data set free from marked variations in directional and intensity effects of the Earth's magnetic field over this extensive region. The resulting data are correlated with long wave length-pass filtered free-air gravity anomalies; regional heat flow, and tectonic data to investigate magatectonic elements and the region's geologic history. Magnetic anomalies are related to both ancient as well as more recent Cenozoic structural features.

  8. Education and Indigenous Knowledge in Africa: Traditional Bonesetting and Orthopaedic Medicine in West Africa

    NASA Astrophysics Data System (ADS)

    Ezeanya, Chika A.

    The underlying philosophy of education in contemporary Africa has been established to be alien, and detached from the indigenous knowledge of the people. Modern day formal education in sub-Saharan Africa came about, for the most part, as a result of missionary activities and colonial efforts of Europe. The education bequeathed to Africa was, therefore, fundamentally European in paradigm and lacking in authenticity. The end of colonialism across sub-Saharan Africa did not herald any tangible transformation in the curriculum of study. Education in Africa is still dependent on foreign input for sustainability, thereby stifling research, creativity and innovation. Sustainable development is founded on indigenous knowledge. When such grassroots knowledge assumes the foundation of learning, home-grown development is easily fostered in all sectors of a national economy. In the field of medicine, indigenous knowledge of healing has been considered unscientific by western biomedical practitioners. Since the days of the missionaries, many Africans have considered indigenous medicine to be fetish; the Christian converts would not be associated with its practice and patronage. However, traditional bonesetting has been proven to be highly efficacious with little supernatural content, it continues to attract huge patronage from Africans, cutting across social and religious boundaries. This study attempts an exploration of the disconnect between indigenous knowledge, practices and learning, on the one hand, and formal education in Africa, on the other. With a focus on traditional bonesetting, the study seeks to determine why that branch of indigenous medicine attracts huge patronage, but is granted very little recognition by modern orthopaedic medical education.

  9. Understanding nutritional epidemiology and its role in policy.

    PubMed

    Satija, Ambika; Yu, Edward; Willett, Walter C; Hu, Frank B

    2015-01-01

    Nutritional epidemiology has recently been criticized on several fronts, including the inability to measure diet accurately, and for its reliance on observational studies to address etiologic questions. In addition, several recent meta-analyses with serious methodologic flaws have arrived at erroneous or misleading conclusions, reigniting controversy over formerly settled debates. All of this has raised questions regarding the ability of nutritional epidemiologic studies to inform policy. These criticisms, to a large degree, stem from a misunderstanding of the methodologic issues of the field and the inappropriate use of the drug trial paradigm in nutrition research. The exposure of interest in nutritional epidemiology is human diet, which is a complex system of interacting components that cumulatively affect health. Consequently, nutritional epidemiology constantly faces a unique set of challenges and continually develops specific methodologies to address these. Misunderstanding these issues can lead to the nonconstructive and sometimes naive criticisms we see today. This article aims to clarify common misunderstandings of nutritional epidemiology, address challenges to the field, and discuss the utility of nutritional science in guiding policy by focusing on 5 broad questions commonly asked of the field.

  10. Understanding Nutritional Epidemiology and Its Role in Policy12

    PubMed Central

    Satija, Ambika; Yu, Edward; Willett, Walter C; Hu, Frank B

    2015-01-01

    Nutritional epidemiology has recently been criticized on several fronts, including the inability to measure diet accurately, and for its reliance on observational studies to address etiologic questions. In addition, several recent meta-analyses with serious methodologic flaws have arrived at erroneous or misleading conclusions, reigniting controversy over formerly settled debates. All of this has raised questions regarding the ability of nutritional epidemiologic studies to inform policy. These criticisms, to a large degree, stem from a misunderstanding of the methodologic issues of the field and the inappropriate use of the drug trial paradigm in nutrition research. The exposure of interest in nutritional epidemiology is human diet, which is a complex system of interacting components that cumulatively affect health. Consequently, nutritional epidemiology constantly faces a unique set of challenges and continually develops specific methodologies to address these. Misunderstanding these issues can lead to the nonconstructive and sometimes naive criticisms we see today. This article aims to clarify common misunderstandings of nutritional epidemiology, address challenges to the field, and discuss the utility of nutritional science in guiding policy by focusing on 5 broad questions commonly asked of the field. PMID:25593140

  11. Multiple co-circulating HIV-1 subtypes in the Middle East and North Africa

    PubMed Central

    Rolland, Morgane; Modjarrad, Kayvon

    2015-01-01

    HIV-1 incidence has been increasing more rapidly in the Middle East and North Africa than in any other global region. Despite this trend, HIV epidemiology in the region remains poorly defined. We conducted an analysis of 3284 publicly available HIV-1 sequences from 15 countries in the Middle East and North Africa to better characterize the regional epidemic. A phylogenetic tree based on the reverse transcriptase gene revealed a complex mosaic of diverse HIV subtypes and circulating recombinant forms across the region. PMID:26091303

  12. Massive Open Online Courses for Africa by Africa

    ERIC Educational Resources Information Center

    Oyo, Benedict; Kalema, Billy Mathias

    2014-01-01

    Africa is known for inadequate access to all sorts of human needs including health, education, food, shelter, transport, security, and energy. Before the emergence of massive open online courses (MOOCs), open access to higher education (HE) was exclusive of Africa. However, as a generally affordable method of post-secondary education delivery,…

  13. Intelligent management of epidemiologic data.

    PubMed Central

    Ferri, F.; Evoli, L. M.; Pisanelli, D. M.; Ricci, F. L.

    1991-01-01

    In the lifecycle of epidemiologic data three steps can be identified: production, interpretation and exploitation for decision. Computerized support can be precious, if not indispensable, at any of the three levels, therefore several epidemiologic data management systems were developed. In this paper we focus on intelligent management of epidemiologic data, where intelligence is needed in order to analyze trends or to compare observed with reference value and possibly detect abnormalities. After having outlined the problems involved in such a task, we show the features of ADAMS, a system realized to manage aggregated data and implemented in a personal computer environment. PMID:1807619

  14. Epidemiology and control of bovine ephemeral fever.

    PubMed

    Walker, Peter J; Klement, Eyal

    2015-01-01

    Bovine ephemeral fever (or 3-day sickness) is an acute febrile illness of cattle and water buffaloes. Caused by an arthropod-borne rhabdovirus, bovine ephemeral fever virus (BEFV), the disease occurs seasonally over a vast expanse of the globe encompassing much of Africa, the Middle East, Asia and Australia. Although mortality rates are typically low, infection prevalence and morbidity rates during outbreaks are often very high, causing serious economic impacts through loss of milk production, poor cattle condition at sale and loss of traction power at harvest. There are also significant impacts on trade to regions in which the disease does not occur, including the Americas and most of Europe. In recent years, unusually severe outbreaks of bovine ephemeral fever have been reported from several regions in Asia and the Middle East, with mortality rates through disease or culling in excess of 10-20%. There are also concerns that, like other vector-borne diseases of livestock, the geographic distribution of bovine ephemeral fever could expand into regions that have historically been free of the disease. Here, we review current knowledge of the virus, including its molecular and antigenic structure, and the epidemiology of the disease across its entire geographic range. We also discuss the effectiveness of vaccination and other strategies to prevent or control infection. PMID:26511615

  15. Epidemiology and control of bovine ephemeral fever.

    PubMed

    Walker, Peter J; Klement, Eyal

    2015-01-01

    Bovine ephemeral fever (or 3-day sickness) is an acute febrile illness of cattle and water buffaloes. Caused by an arthropod-borne rhabdovirus, bovine ephemeral fever virus (BEFV), the disease occurs seasonally over a vast expanse of the globe encompassing much of Africa, the Middle East, Asia and Australia. Although mortality rates are typically low, infection prevalence and morbidity rates during outbreaks are often very high, causing serious economic impacts through loss of milk production, poor cattle condition at sale and loss of traction power at harvest. There are also significant impacts on trade to regions in which the disease does not occur, including the Americas and most of Europe. In recent years, unusually severe outbreaks of bovine ephemeral fever have been reported from several regions in Asia and the Middle East, with mortality rates through disease or culling in excess of 10-20%. There are also concerns that, like other vector-borne diseases of livestock, the geographic distribution of bovine ephemeral fever could expand into regions that have historically been free of the disease. Here, we review current knowledge of the virus, including its molecular and antigenic structure, and the epidemiology of the disease across its entire geographic range. We also discuss the effectiveness of vaccination and other strategies to prevent or control infection.

  16. Regions. [Africa, Middle East].

    PubMed

    1985-03-01

    This discussion of population focuses on the regions of Africa and the Middle East. In South Africa more white women are working but fewer black women work. The overall result is that the percentage of women who work is declining. Marita de Beer, research liaison executive at the South African Advertising Research Foundation, reports that the female population grew by 31% in the past 10 years while the number of working women has grown by only 11%. Among blacks the female population rose by 36%, but the number of workers among them declined by about 1%. Married women are among the fastest growing groups of working women in South Africa. The most recent estimate of the population of Nigeria is 92 million. According to Professor Vremudia Diejomaoh, Nigeria's population will probably reach 155 million by 2000 with 33% living in urban areas. In Saudi Arabia the Pan Arab Research Center recently completed a census of retail outlets in 3 metropolitan areas: Jeddah, Riyadh, and Dammam. The types of outlets surveyed include large supermarkets, small supermarkets, groceries with and without deep freeze, tobacco shops, meat shop/delis, small cafeterias, large restaurants/hotels, cosmetics shops or perfumeries, camera stores, toy shops, pharmacies, watch and gift shop, newsstands, department store, and appliance outlets. Using the Census of Retail Outlets as a base, Pan Arab Research Center also has a new distribution audit system that will cover 500 outlets. By plotting Arab countries according to their population policies and their current growth rates, it is possible to project where the middle class will grow fastest in the Arab world. The countries that have declining growth rates and strong population programs designed to encourage lower fertility rates among women are Egypt, Tunisia, Morocco, Algeria, and Lebanon. The countries most likely to have a better per capita distribution of resources within this decade are those where governments encourage reductions in

  17. Regions. [Africa, Middle East].

    PubMed

    1985-03-01

    This discussion of population focuses on the regions of Africa and the Middle East. In South Africa more white women are working but fewer black women work. The overall result is that the percentage of women who work is declining. Marita de Beer, research liaison executive at the South African Advertising Research Foundation, reports that the female population grew by 31% in the past 10 years while the number of working women has grown by only 11%. Among blacks the female population rose by 36%, but the number of workers among them declined by about 1%. Married women are among the fastest growing groups of working women in South Africa. The most recent estimate of the population of Nigeria is 92 million. According to Professor Vremudia Diejomaoh, Nigeria's population will probably reach 155 million by 2000 with 33% living in urban areas. In Saudi Arabia the Pan Arab Research Center recently completed a census of retail outlets in 3 metropolitan areas: Jeddah, Riyadh, and Dammam. The types of outlets surveyed include large supermarkets, small supermarkets, groceries with and without deep freeze, tobacco shops, meat shop/delis, small cafeterias, large restaurants/hotels, cosmetics shops or perfumeries, camera stores, toy shops, pharmacies, watch and gift shop, newsstands, department store, and appliance outlets. Using the Census of Retail Outlets as a base, Pan Arab Research Center also has a new distribution audit system that will cover 500 outlets. By plotting Arab countries according to their population policies and their current growth rates, it is possible to project where the middle class will grow fastest in the Arab world. The countries that have declining growth rates and strong population programs designed to encourage lower fertility rates among women are Egypt, Tunisia, Morocco, Algeria, and Lebanon. The countries most likely to have a better per capita distribution of resources within this decade are those where governments encourage reductions in

  18. [Epidemiology of AIDS].

    PubMed

    1988-02-01

    The World Health Organization (WHO) estimates that some 300,000 AIDS cases will be diagnosed by the end of 1988. As of December 1987, 128 countries had reported a total of 72,000 cases, about half the number of cases that actually occurred. The WHO estimates that some 5-10 million persons are already infected with HIV, so that the number of AIDS cases will increase rapidly for the next 5 years at least. The number of cases reported in Africa increased considerably in 1987, reflecting greater awareness of AIDS and greater efforts at control. By late 1987 WHO was working actively with over 100 countries to combat AIDS. An expert meeting organized by the WHO Special Program to Combat AIDS recommended to governments and prison administrators that condoms be provided to inmates and that treatment programs be provided for intravenous drug addicts. Prison personnel should receive education about HIV infection and AIDS. Incarceration policies, especially for drug addicts, should be reviewed in light of the AIDS epidemic. An estimated average of 10% of the 270,000 prisoners enumerated in 17 European countries are believed to be HIV positive, but the proportion increases to 26% in the highest risk countries. The proportion of seropositive subjects in general exceeds that in the total population. Prison and health officials will be obliged to assign increasing resources to AIDS in prisons in the years to come. PMID:3201571

  19. Planning for the Future of Epidemiology in the Era of Big Data and Precision Medicine

    PubMed Central

    Khoury, Muin J.

    2015-01-01

    We live in the era of genomics and big data. Evaluating the impact on health of large-scale biological, social, and environmental data is an emerging challenge in the field of epidemiology. In the past 3 years, major discussions and plans for the future of epidemiology, including with several recommendations for actions to transform the field, have been launched by 2 institutes within the National Institutes of Health. In the present commentary, I briefly explore the themes of these recommendations and their effects on leadership, resources, cohort infrastructure, and training. Ongoing engagement within the epidemiology community is needed to determine how to shape the evolution of the field and what truly matters for changing population health. We also need to assess how to leverage existing epidemiology resources and develop new studies to improve human health. Readers are invited to examine these recommendations, consider others that might be important, and join in the conversation about the future of epidemiology. PMID:26628513

  20. Planning for the Future of Epidemiology in the Era of Big Data and Precision Medicine.

    PubMed

    Khoury, Muin J

    2015-12-15

    We live in the era of genomics and big data. Evaluating the impact on health of large-scale biological, social, and environmental data is an emerging challenge in the field of epidemiology. In the past 3 years, major discussions and plans for the future of epidemiology, including with several recommendations for actions to transform the field, have been launched by 2 institutes within the National Institutes of Health. In the present commentary, I briefly explore the themes of these recommendations and their effects on leadership, resources, cohort infrastructure, and training. Ongoing engagement within the epidemiology community is needed to determine how to shape the evolution of the field and what truly matters for changing population health. We also need to assess how to leverage existing epidemiology resources and develop new studies to improve human health. Readers are invited to examine these recommendations, consider others that might be important, and join in the conversation about the future of epidemiology.

  1. Zika Virus Outside Africa

    PubMed Central

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas. PMID:19788800

  2. Zika virus outside Africa.

    PubMed

    Hayes, Edward B

    2009-09-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas.

  3. Immunology in Africa.

    PubMed

    Cose, Stephen; Bagaya, Bernard; Nerima, Barbara; Joloba, Moses; Kambugu, Andrew; Tweyongyere, Robert; Dunne, David W; Mbidde, Edward; Kaleebu, Pontiano; Elliott, Alison M

    2015-12-01

    Africa is a continent with a large burden of both infectious and non-communicable diseases. If we are to move forward as a continent, we need to equip our growing cadre of exceptional young scientists with the skills needed to tackle the diseases endemic to this continent. For this, immunology is among the key disciplines. Africans should be empowered to study and understand the diseases that affect them, and to perform their cutting-edge research in their country of origin. This requires a multifaceted approach, with buy-in from funders, overseas partners and perhaps, most important of all, African governments themselves.

  4. Initiatives in Africa.

    PubMed

    Goliber, T J; Middleberg, M I

    1986-03-01

    Since the 1st oil crisis in 1973, the economies of sub-Saharan Africa have barely kept pace with their burgeoning populations. Women in Sub-Saharan Africa give birth more often than women in any other region of the world, with an average of more than 6.5 live births each. The region's natural increase average 2.5% a year in the 1960s, 2.7% in the 1970s, and in the mid-1980s, it is 3.1% per annum--a rate that will double the regions population in 22 years. National leaders in Sub-Saharan Africa were slow to consider population policy as a key component of the social and economic development effort. The neglect of population issues is reflected in the limited scope of public or private family planning programs in the sub-continent. Donor countries and institutions play an important role in developing the information base by providing technical training to government staff, supporting research, and disseminating information to a broad spectrum of political actors. Some examples of policy reconsiderations in Nigeria, Zambia, Liberia, and Niger are given. These countries are starting to give active consideration to population policies to reduce fertility and high rates of population growth by expanding family planning services, raising the age of marriage, improving the status of women, providing family-life education, and incorporating economic incentives for smaller families into the provision of social services. The highly centralized nature of African governments dictates that the acquiescence of the governmental elite must be obtained before any policy can take hold. Overall, high population growth rates in combination with a stagnating social and economic development effort throughout the region have provided the catalyst for a new look at Sub-Saharan Africa population policy. The ability of African nations to implement policies that reduce fertility is more open to question; no African nation has as yet done so, and the socioeconomics factors contributing to high

  5. Update on the epidemiology of tuberculosis in Italy.

    PubMed

    Conversano, Michele

    2014-05-01

    As in many countries in Western Europe, in Italy tuberculosis (TB) is a relatively rare disease. In the last decade its incidence has remained constant at under 10 cases/100,000 inhabitants, the threshold considered to define a country as low prevalence. The epidemiological picture, however, is very different in the countries of Eastern Europe and in Africa, Asia, and Latin America, where the incidence of TB continues to increase and in some cases is accompanied by the emergence and spread of multidrug-resistant TB. The present review describes the epidemiology of TB in Italy. In 2008, the incidence rate was 3.8 cases per 100,000 for people born in Italy, and 50-60 cases per 100,000 for those born abroad. There was an increase in cases from Eastern Europe. The crude mortality rate for TB in 2006 was 0.7 deaths per 100,000 residents. Although TB is a low-prevalence disease in Italy, its epidemiology is changing. Since 1955, more than 160,000 people in Italy have died from this potentially preventable and curable disease.

  6. Update on the epidemiology of tuberculosis in Italy.

    PubMed

    Conversano, Michele

    2014-05-01

    As in many countries in Western Europe, in Italy tuberculosis (TB) is a relatively rare disease. In the last decade its incidence has remained constant at under 10 cases/100,000 inhabitants, the threshold considered to define a country as low prevalence. The epidemiological picture, however, is very different in the countries of Eastern Europe and in Africa, Asia, and Latin America, where the incidence of TB continues to increase and in some cases is accompanied by the emergence and spread of multidrug-resistant TB. The present review describes the epidemiology of TB in Italy. In 2008, the incidence rate was 3.8 cases per 100,000 for people born in Italy, and 50-60 cases per 100,000 for those born abroad. There was an increase in cases from Eastern Europe. The crude mortality rate for TB in 2006 was 0.7 deaths per 100,000 residents. Although TB is a low-prevalence disease in Italy, its epidemiology is changing. Since 1955, more than 160,000 people in Italy have died from this potentially preventable and curable disease. PMID:24788994

  7. Using an Epidemiological Approach to Examine Outcomes Affecting Young Children with Down Syndrome and Their Families

    ERIC Educational Resources Information Center

    Hodapp, Robert M.; Urbano, Richard C.; So, Stephanie A.

    2006-01-01

    In this paper, we utilise an approach drawn from the field of epidemiology to explore what is known and unknown about young children with Down syndrome and their families. After describing what we mean by an epidemiological approach, we review basic findings for children with intellectual disabilities, as well as challenges to performing such…

  8. Epidemiology of Lung Cancer

    PubMed Central

    Brock, Malcolm V.; Ford, Jean G.; Samet, Jonathan M.; Spivack, Simon D.

    2013-01-01

    Background: Ever since a lung cancer epidemic emerged in the mid-1900s, the epidemiology of lung cancer has been intensively investigated to characterize its causes and patterns of occurrence. This report summarizes the key findings of this research. Methods: A detailed literature search provided the basis for a narrative review, identifying and summarizing key reports on population patterns and factors that affect lung cancer risk. Results: Established environmental risk factors for lung cancer include smoking cigarettes and other tobacco products and exposure to secondhand tobacco smoke, occupational lung carcinogens, radiation, and indoor and outdoor air pollution. Cigarette smoking is the predominant cause of lung cancer and the leading worldwide cause of cancer death. Smoking prevalence in developing nations has increased, starting new lung cancer epidemics in these nations. A positive family history and acquired lung disease are examples of host factors that are clinically useful risk indicators. Risk prediction models based on lung cancer risk factors have been developed, but further refinement is needed to provide clinically useful risk stratification. Promising biomarkers of lung cancer risk and early detection have been identified, but none are ready for broad clinical application. Conclusions: Almost all lung cancer deaths are caused by cigarette smoking, underscoring the need for ongoing efforts at tobacco control throughout the world. Further research is needed into the reasons underlying lung cancer disparities, the causes of lung cancer in never smokers, the potential role of HIV in lung carcinogenesis, and the development of biomarkers. PMID:23649439

  9. Shigellosis: Epidemiology in India

    PubMed Central

    Taneja, Neelam; Mewara, Abhishek

    2016-01-01

    Shigellosis is one of the major causes of diarrhoea in India. The accurate estimates of morbidity and mortality due to shigellosis are lacking, though it is endemic in the country and has been reported to cause many outbreaks. The limited information available indicates Shigella to be an important food-borne pathogen in India. S. flexneri is the most common species, S. sonnei and non-agglutinable shigellae seem to be steadily surfacing, while S. dysenteriae has temporarily disappeared from the northern and eastern regions. Antibiotic-resistant strains of different Shigella species and serotypes have emerged all over the world. Especially important is the global emergence of multidrug resistant shigellae, notably the increasing resistance to third generation cephalosporins and fluoroquinolones, and also azithromycin. This calls for a continuous and strong surveillance of antibiotic resistance across the country for periodic updation of the local antibiograms. The prevention of shigellosis is desirable as it will substantially reduce the morbidity associated with diarrhoea in the country. Public health measures like provision of safe water and adequate sanitation are of immense importance to reduce the burden of shigellosis, however, the provision of resources to develop such an infrastructure in India is a complex issue and will take time to resolve. Thus, the scientific thrust should be focused towards development of a safe and affordable multivalent vaccine. This review is focused upon the epidemiology, disease burden and the therapeutic challenges of shigellosis in Indian perspective. PMID:27487999

  10. Epidemiology of severe trauma.

    PubMed

    Alberdi, F; García, I; Atutxa, L; Zabarte, M

    2014-12-01

    Major injury is the sixth leading cause of death worldwide. Among those under 35 years of age, it is the leading cause of death and disability. Traffic accidents alone are the main cause, fundamentally in low- and middle-income countries. Patients over 65 years of age are an increasingly affected group. For similar levels of injury, these patients have twice the mortality rate of young individuals, due to the existence of important comorbidities and associated treatments, and are more likely to die of medical complications late during hospital admission. No worldwide, standardized definitions exist for documenting, reporting and comparing data on severely injured trauma patients. The most common trauma scores are the Abbreviated Injury Scale (AIS), the Injury Severity Score (ISS) and the Trauma and Injury severity Score (TRISS). Documenting the burden of injury also requires evaluation of the impact of post-trauma impairments, disabilities and handicaps. Trauma epidemiology helps define health service and research priorities, contributes to identify disadvantaged groups, and also facilitates the elaboration of comparable measures for outcome predictions.

  11. Epidemiology of delayed ejaculation

    PubMed Central

    Di Sante, Stefania; Mollaioli, Daniele; Gravina, Giovanni Luca; Ciocca, Giacomo; Limoncin, Erika; Carosa, Eleonora; Lenzi, Andrea

    2016-01-01

    A large body of literature on diminished ejaculatory disorders has been generated without the use of a clear diagnostic definition. Many studies have not distinguished between the orgasm and ejaculation disorders leading to doubtful results. Delayed ejaculation (DE) is one of the diminished ejaculatory disorders, which range from varying delays in ejaculatory latency to a complete inability to ejaculate. The present review is aimed at providing a comprehensive overview of the current knowledge on the definition and epidemiology of diminished ejaculatory disorders. We focus on the acquired diseases, such as benign prostatic hyperplasia (BPH) and specific drug regimens that may cause an iatrogenic form of ejaculatory disorder. In addition, the impact of aging is discussed since the prevalence of DE appears to be moderately but positively related to age. Finally, we also focus on the importance of the hormonal milieu on male ejaculation. To date, evidence on the endocrine control of ejaculation is derived from small clinical trials, but the evidence suggests that hormones modulate the ejaculatory process by altering its overall latency. PMID:27652226

  12. Epidemiology of severe trauma.

    PubMed

    Alberdi, F; García, I; Atutxa, L; Zabarte, M

    2014-12-01

    Major injury is the sixth leading cause of death worldwide. Among those under 35 years of age, it is the leading cause of death and disability. Traffic accidents alone are the main cause, fundamentally in low- and middle-income countries. Patients over 65 years of age are an increasingly affected group. For similar levels of injury, these patients have twice the mortality rate of young individuals, due to the existence of important comorbidities and associated treatments, and are more likely to die of medical complications late during hospital admission. No worldwide, standardized definitions exist for documenting, reporting and comparing data on severely injured trauma patients. The most common trauma scores are the Abbreviated Injury Scale (AIS), the Injury Severity Score (ISS) and the Trauma and Injury severity Score (TRISS). Documenting the burden of injury also requires evaluation of the impact of post-trauma impairments, disabilities and handicaps. Trauma epidemiology helps define health service and research priorities, contributes to identify disadvantaged groups, and also facilitates the elaboration of comparable measures for outcome predictions. PMID:25241267

  13. AIDS in women: epidemiology.

    PubMed

    Willoughby, A

    1989-09-01

    Several facts concerning the distribution of AIDS in U.S. female populations are clear. This disease has made significant inroads, in a quantitative sense, into the female segment of our society as documented by AIDS surveillance data, information on pregnant women and parturients, and by screening data from the military. The impact on women in the reproductive years, on the reproductive health of these women, and on the reproductive outcome of their pregnancies is of substantial concern. Monitoring epidemiologic trends in certain groups will require clever and creative strategies like those of Hoff and colleagues. Additional data may be derived from the CDC's Family of Surveys that will examine HIV prevalence in five groups (in addition to the newborn infant survey described above): intravenous drug users, patients admitted to hospitals, sexually transmitted disease clinic patients, women's health and reproductive health clinics, and tuberculosis clinics. It is hoped that the data obtained from these studies, as well as data gathered on college students and Job Corps applicants, will contribute additional information on HIV infection in women. Monitoring the progress of the AIDS epidemic in women will be difficult. Even more difficult will be the effort to respond to the epidemic in the women it most frequently affects: the poor, minority, disenfranchised women who may be involved in illegal activities (drug use, prostitution, illegal immigration) who are not well networked into the medical and social services of our society. PMID:2776374

  14. Shigellosis: Epidemiology in India.

    PubMed

    Taneja, Neelam; Mewara, Abhishek

    2016-05-01

    Shigellosis is one of the major causes of diarrhoea in India. The accurate estimates of morbidity and mortality due to shigellosis are lacking, though it is endemic in the country and has been reported to cause many outbreaks. The limited information available indicates Shigella to be an important food- borne pathogen in India. S. flexneri is the most common species, S. sonnei and non-agglutinable Shigellae seem to be steadily surfacing, while S. dysenteriae has temporarily disappeared from the northern and eastern regions. Antibiotic-resistant strains of different Shigella species and serotypes have emerged all over the world. Especially important is the global emergence of multidrug resistant Shigellae, notably the increasing resistance to third generation cephalosporins and fluoroquinolones, and also azithromycin. This calls for a continuous and strong surveillance of antibiotic resistance across the country for periodic updation of the local antibiograms. The prevention of shigellosis is desirable as it will substantially reduce the morbidity associated with diarrhoea in the country. Public health measures like provision of safe water and adequate sanitation are of immense importance to reduce the burden of shigellosis, however, the provision of resources to develop such an infrastructure in India is a complex issue and will take time to resolve. Thus, the scientific thrust should be focused towards development of a safe and affordable multivalent vaccine. this review is focused upon the epidemiology, disease burden and the therapeutic challenges of shigellosis in Indian perspective. PMID:27487999

  15. Epidemiology of clavicle fractures.

    PubMed

    Postacchini, Franco; Gumina, Stefano; De Santis, Pierfrancesco; Albo, Francesco

    2002-01-01

    An epidemiologic study of 535 isolated clavicle fractures treated in a hospital of a large metropolis during an 11-year period was performed. Data regarding patient's age and sex, side involved, mechanism of injury, and season in which the fracture occurred were obtained from the clinical records. Radiographic classification was performed with the Allman system. Clavicle fractures represented 2.6% of all fractures and 44% of those in the shoulder girdle. Most patients were men (68%), and the left side was involved in 61% of cases. Fractures of the middle third of the clavicle, which were the most common (81%), were displaced in 48% of cases and comminuted in 19%. Fractures of the medial third were the least common (2%). The prevalence of midclavicular fractures was found to decrease progressively with age, starting from the first decade of life when they represented 88.2% of all clavicle fractures and were undisplaced in 55.5% of cases. In adults, the incidence of displaced fractures, independent of location, was higher than that of undisplaced fractures. Traffic accidents were the most common cause of the injury. In the period under study, the incidence of fractures showed no significant change over time and no seasonal variation. PMID:12378163

  16. [Epidemiology of teeth hypersensitivity].

    PubMed

    Lutskaia, I K; Zinovenko, O G; Kovalenko, I P

    2015-01-01

    A clinical examination of 98 patients aged 20 to 75 years was carried out to identifyclinical and epidemiological features of hard tooth tissueshypersensitivity. The survey found out what stimuli (cold, hot, sour, mechanical, chemical) cause the appearance of dental hyperesthesia. The detailed survey of the affected area aimed to determine the presence of dental caries, gingival recession, wedge-shaped defects, erosions, microcracks and chipped enamel, as well as wear of the tooth crown. Forty-threepatients of 98 (43.88%) had tooth sensitivity. Most affected age group was 25-34 years (33%). Among patients studied with hyperesthesia 86% complained of pain. It was establishedthat dental hyperesthesia most often causes an intense, but quickly passing pain response, wherein upon exposure of several types of stimuli. Teeth with high sensitivity showed signs of abrasion (74.1%), most often--on the vestibular surface (44.4%). Patients under 45 years had notable cracks and wedge-shaped defects. In patients 45 years and older cracks and increased abrasion of hard dental tissues was seen. PMID:26271696

  17. Epidemiology of delayed ejaculation

    PubMed Central

    Di Sante, Stefania; Mollaioli, Daniele; Gravina, Giovanni Luca; Ciocca, Giacomo; Limoncin, Erika; Carosa, Eleonora; Lenzi, Andrea

    2016-01-01

    A large body of literature on diminished ejaculatory disorders has been generated without the use of a clear diagnostic definition. Many studies have not distinguished between the orgasm and ejaculation disorders leading to doubtful results. Delayed ejaculation (DE) is one of the diminished ejaculatory disorders, which range from varying delays in ejaculatory latency to a complete inability to ejaculate. The present review is aimed at providing a comprehensive overview of the current knowledge on the definition and epidemiology of diminished ejaculatory disorders. We focus on the acquired diseases, such as benign prostatic hyperplasia (BPH) and specific drug regimens that may cause an iatrogenic form of ejaculatory disorder. In addition, the impact of aging is discussed since the prevalence of DE appears to be moderately but positively related to age. Finally, we also focus on the importance of the hormonal milieu on male ejaculation. To date, evidence on the endocrine control of ejaculation is derived from small clinical trials, but the evidence suggests that hormones modulate the ejaculatory process by altering its overall latency.

  18. Rosacea: current state of epidemiology.

    PubMed

    Tan, Jerry; Berg, Mats

    2013-12-01

    Case definitions are critical in epidemiologic research. However, modern disease indicators must now consider complex data from gene-based research along with traditional clinical parameters. Rosacea is a skin disorder with multiple signs and symptoms. In individuals, these features may be multiple or one may predominate. While studies on the epidemiology of rosacea have previously been sparse, there has been a recent increase in research activity. A broader body of epidemiological information that includes a greater variety of countries beyond Northern Europe and general population-based demographics is needed. As there are operational issues in current case definitions of rosacea subtypes--rationalization and standardization--universal consistent applications in future research is also imperative. Further improvement in disease definition combining new research information along with clinical pragmatism should increase the accuracy of rosacea case ascertainment and facilitate further epidemiological research.

  19. Sample Cancer Epidemiology Grant Applications

    Cancer.gov

    The National Cancer Institute frequently receives questions from investigators for examples of successfully funded grant applications. Several investigators agreed to let the Epidemiology and Genomics Research Program post excerpts of their grant applications online.

  20. Genomic Resources for Cancer Epidemiology

    Cancer.gov

    This page provides links to research resources, complied by the Epidemiology and Genomics Research Program, that may be of interest to genetic epidemiologists conducting cancer research, but is not exhaustive.