Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-26 (of 26 Records) |
Query Trace: Mathieu E[original query] |
---|
Countrywide insecticide resistance monitoring and first report of the presence of the L1014S knock down resistance in Niger, West Africa
Soumaila H , Hamani B , Arzika II , Soumana A , Daouda A , Daouda FA , Iro SM , Gouro S , Zaman-Allah MS , Mahamadou I , Kadri S , Sal NM , Hounkanrin W , Mahamadou B , Zamaka HN , Labbo R , Laminou IM , Jackou H , Idrissa S , Coulibaly E , Bahari-Tohon Z , Mathieu E , Carlson J , Dotson E , Awolola TS , Flatley C , Chabi J . Malar J 2022 21 (1) 385 BACKGROUND: Mass distribution of insecticide-treated nets (ITNs) is the principal malaria vector control strategy adopted by Niger. To better inform on the most appropriate ITN to distribute, the National Malaria Control Programme (NMCP) of Niger and its partners, conducted insecticide resistance monitoring in selected sites across the country. METHODS: The susceptibility of Anopheles gambiae sensu lato (s.l.) to chlorfenapyr and pyrethroid insecticides was investigated in a total of sixteen sites in 2019 and 2020, using 2-5-day-old adults reared from wild collected larvae per site. The susceptibility status, pyrethroid resistance intensity at 5 and 10 times the diagnostic concentrations, and piperonyl butoxide (PBO) synergism with diagnostic concentrations of deltamethrin, permethrin and alpha-cypermethrin were assessed using WHO bioassays. Two doses (100 and 200g/bottle) of chlorfenapyr were tested using the CDC bottle assay method. Species composition and allele frequencies for knock-down resistance (kdr-L1014F and L1014S) and acetylcholinesterase (ace-1 G119S) mutations were further characterized using polymerase chain reaction (PCR). RESULTS: High resistance intensity to all pyrethroids tested was observed in all sites except for alpha-cypermethrin in Gaya and Tessaoua and permethrin in Gaya in 2019 recording moderate resistance intensity. Similarly, Balleyara, Keita and Tillabery yielded moderate resistance intensity for alpha-cypermethrin and deltamethrin, and Niamey V low resistance intensity against deltamethrin and permethrin in 2020. Pre-exposure to PBO substantially increased susceptibility with average increases in mortality between 0 and 70% for tested pyrethroids. Susceptibility to chlorfenapyr (100g/bottle) was recorded in all sites except in Tessaoua and Magaria where susceptibility was recorded at the dose of 200g/bottle. Anopheles coluzzii was the predominant malaria vector species in most of the sites followed by An. gambiae sensu stricto (s.s.) and Anopheles arabiensis. The kdr-L1014S allele, investigated for the first time, was detected in the country. Both kdr-L1014F (frequencies [0.46-0.81]) and L1014S (frequencies [0.41-0.87]) were present in all sites while the ace-1 G119S was between 0.08 and 0.20. CONCLUSION: The data collected will guide the NMCP in making evidence-based decisions to better adapt vector control strategies and insecticide resistance management in Niger, starting with mass distribution of new generation ITNs such as interceptor G2 and PBO ITNs. |
Local emergence in Amazonia of Plasmodium falciparum k13 C580Y mutants associated with in vitro artemisinin resistance.
Mathieu LC , Cox H , Early AM , Mok S , Lazrek Y , Paquet JC , Ade MP , Lucchi NW , Grant Q , Udhayakumar V , Alexandre JS , Demar M , Ringwald P , Neafsey DE , Fidock DA , Musset L . Elife 2020 9 Antimalarial drug resistance has historically arisen through convergent de novo mutations in Plasmodium falciparum parasite populations in Southeast Asia and South America. For the past decade in Southeast Asia, artemisinins, the core component of first-line antimalarial therapies, have experienced delayed parasite clearance associated with several pfk13 mutations, primarily C580Y. We report that mutant pfk13 has emerged independently in Guyana, with genome analysis indicating an evolutionary origin distinct from Southeast Asia. Pfk13 C580Y parasites were observed in 1.6% (14/854) of samples collected in Guyana in 2016-2017. Introducing pfk13 C580Y or R539T mutations by gene editing into local parasites conferred high levels of in vitro artemisinin resistance. In vitro growth competition assays revealed a fitness cost associated with these pfk13 variants, potentially explaining why these resistance alleles have not increased in frequency more quickly in South America. These data place local malaria control efforts at risk in the Guiana Shield. | All recommended treatments against malaria include a drug called artemisinin or some of its derivatives. However, there are concerns that Plasmodium falciparum, the parasite that causes most cases of malaria, will eventually develop widespread resistance to the drug. A strain of P. falciparum partially resistant to artemisinin was seen in Cambodia in 2008, and it has since spread across Southeast Asia. The resistance appears to be frequently linked to a mutation known as pfk13 C580Y. Southeast Asia and Amazonia are considered to be hotspots for antimalarial drug resistance, and the pfk13 C580Y mutation was detected in the South American country of Guyana in 2010. To examine whether the mutation was still circulating in this part of the world, Mathieu et al. collected and analyzed 854 samples across Guyana between 2016 and 2017. Overall, 1.6% of the samples had the pfk13 C580Y mutation, but this number was as high as 8.8% in one region. Further analyses revealed that the mutation in Guyana had not spread from Southeast Asia, but that it had occurred in Amazonia independently. To better understand the impact of the pfk13 C580Y mutation, Mathieu et al. introduced this genetic change into non-resistant parasites from a country neighbouring Guyana. As expected, the mutation made P. falciparum highly resistant to artemisinin, but it also slowed the growth rate of the parasite. This disadvantage may explain why the mutation has not spread more rapidly through Guyana in recent years. Artemisinin and its derivatives are always associated with other antimalarial drugs to slow the development of resistance; there are concerns that reduced susceptibility to artemisinin leads to the parasites becoming resistant to the partner drugs. Further research is needed to evaluate how the pfk13 C580Y mutation affects the parasite's response to the typical combination of drugs that are given to patients. | eng |
Outbreak of Listeriosis in South Africa Associated with Processed Meat.
Thomas J , Govender N , McCarthy KM , Erasmus LK , Doyle TJ , Allam M , Ismail A , Ramalwa N , Sekwadi P , Ntshoe G , Shonhiwa A , Essel V , Tau N , Smouse S , Ngomane HM , Disenyeng B , Page NA , Govender NP , Duse AG , Stewart R , Thomas T , Mahoney D , Tourdjman M , Disson O , Thouvenot P , Maury MM , Leclercq A , Lecuit M , Smith AM , Blumberg LH . N Engl J Med 2020 382 (7) 632-643 BACKGROUND: An outbreak of listeriosis was identified in South Africa in 2017. The source was unknown. METHODS: We conducted epidemiologic, trace-back, and environmental investigations and used whole-genome sequencing to type Listeria monocytogenes isolates. A case was defined as laboratory-confirmed L. monocytogenes infection during the period from June 11, 2017, to April 7, 2018. RESULTS: A total of 937 cases were identified, of which 465 (50%) were associated with pregnancy; 406 of the pregnancy-associated cases (87%) occurred in neonates. Of the 937 cases, 229 (24%) occurred in patients 15 to 49 years of age (excluding those who were pregnant). Among the patients in whom human immunodeficiency virus (HIV) status was known, 38% of those with pregnancy-associated cases (77 of 204) and 46% of the remaining patients (97 of 211) were infected with HIV. Among 728 patients with a known outcome, 193 (27%) died. Clinical isolates from 609 patients were sequenced, and 567 (93%) were identified as sequence type 6 (ST6). In a case-control analysis, patients with ST6 infections were more likely to have eaten polony (a ready-to-eat processed meat) than those with non-ST6 infections (odds ratio, 8.55; 95% confidence interval, 1.66 to 43.35). Polony and environmental samples also yielded ST6 isolates, which, together with the isolates from the patients, belonged to the same core-genome multilocus sequence typing cluster with no more than 4 allelic differences; these findings showed that polony produced at a single facility was the outbreak source. A recall of ready-to-eat processed meat products from this facility was associated with a rapid decline in the incidence of L. monocytogenes ST6 infections. CONCLUSIONS: This investigation showed that in a middle-income country with a high prevalence of HIV infection, L. monocytogenes caused disproportionate illness among pregnant girls and women and HIV-infected persons. Whole-genome sequencing facilitated the detection of the outbreak and guided the trace-back investigations that led to the identification of the source. |
Asymptomatic orthopoxvirus circulation in humans in the wake of a monkeypox outbreak among chimpanzees in Cameroon
Guagliardo SAJ , Monroe B , Moundjoa C , Athanase A , Okpu G , Burgado J , Townsend MB , Satheshkumar PS , Epperson S , Doty JB , Reynolds MG , Dibongue EE , Etoundi GA , Mathieu E , McCollum AM . Am J Trop Med Hyg 2019 102 (1) 206-212 Monkeypox virus is a zoonotic Orthopoxvirus (OPXV) that causes smallpox-like illness in humans. In Cameroon, human monkeypox cases were confirmed in 2018, and outbreaks in captive chimpanzees occurred in 2014 and 2016. We investigated the OPXV serological status among staff at a primate sanctuary (where the 2016 chimpanzee outbreak occurred) and residents from nearby villages, and describe contact with possible monkeypox reservoirs. We focused specifically on Gambian rats (Cricetomys spp.) because it is a recognized possible reservoir and because contact with this species was common enough to render sufficient statistical power. We collected one 5-mL whole blood specimen from each participant to perform a generic anti-OPXV ELISA test for IgG and IgM antibodies and administered a questionnaire about prior symptoms of monkeypox-like illness and contact with possible reservoirs. Our results showed evidence of OPXV exposures (IgG positive, 6.3%; IgM positive, 1.6%) among some of those too young to have received smallpox vaccination (born after 1980, n = 63). No participants reported prior symptoms consistent with monkeypox. After adjusting for the education level, participants who frequently visited the forest were more likely to have recently eaten Gambian rats (OR: 3.36, 95% CI: 1.91-5.92, P < 0.001) and primate sanctuary staff were less likely to have touched or sold Gambian rats (OR: 0.23, 95% CI: 0.19-0.28, P < 0.001). The asymptomatic or undetected circulation of OPXVs in humans in Cameroon is likely, and contact with monkeypox reservoirs is common, raising the need for continued surveillance for human and animal disease. |
Evaluation of diarrheal disease surveillance in the Minawao refugee camp - Cameroon, 2016
Amabo FC , Seukap EC , Mathieu E , Etoundi GA . Int J Infect Dis 2019 82 9-14 BACKGROUND: Between 2013 and 2015, the Minawao refugee camp in Cameroon received about 51,000 refugees fleeing Boko Haram. Rapid population increase and inadequate sanitary installations increase the risk of diarrheal disease, thus we assessed the structure and attributes of the surveillance system in Minawao. METHODS: We used updated CDC guidelines for evaluating public health surveillance systems. Information sources included health registers, surveillance reports, and key informant interviews. We used scorecards to assess the system's simplicity, flexibility, data quality, acceptability, sensitivity, timeliness, stability and usefulness. RESULTS: Surveillance in Minawao is both passive and active, integrating four diseases reported weekly/immediately. All key informants agreed that surveillance was part of their routine work. Of 138 surveillance reports reviewed, all were complete; 91 (66%) were timely. Overall, 143 (100%) cases of diarrheal disease identified in health registers were reported to the next level. Only two (20%) surveillance personnel could correctly state standardized case definitions (SCD); three (30%) were unable to identify cases of diarrheal disease based on SCD. CONCLUSIONS: In Minawao, diarrheal disease surveillance is acceptable, flexible, sensitive, and useful. To improve timeliness and use of SCD, we recommend using mobile phones for reporting and displaying SCD in health facilities. |
Temporal and geographic patterns of social media posts about an emerging suicide game
Sumner SA , Galik S , Mathieu J , Ward M , Kiley T , Bartholow B , Dingwall A , Mork P . J Adolesc Health 2019 65 (1) 94-100 PURPOSE: Rates of suicide are increasing rapidly among youth. Social media messages and online games promoting suicide are a concern for parents and clinicians. We examined the timing and location of social media posts about one alleged youth suicide game to better understand the degree to which social media data can provide earlier public health awareness. METHODS: We conducted a search of all public social media posts and news articles on the Blue Whale Challenge (BWC), an alleged suicide game, from January 1, 2013, through June 30, 2017. Data were retrieved through multiple keyword search; sources included social media platforms Twitter, YouTube, Reddit, Tumblr, as well as blogs, forums, and news articles. Posts were classified into three categories: individual "pro"-BWC posts (support for game), individual "anti"-BWC posts (opposition to game), and media reports. Timing and location of posts were assessed. RESULTS: Overall, 95,555 social media posts and articles about the BWC were collected. In total, over one-quarter (28.3%) were "pro"-BWC. The first U.S. news article related to the BWC was published approximately 4 months after the first English language U.S. social media post about the BWC and 9 months after the first U.S. social media post in any language. By the close of the study period, "pro"-BWC posts had spread to 127 countries. CONCLUSIONS: Novel online risks to mental health, such as prosuicide games or messages, can spread rapidly and globally. Better understanding social media and Web data may allow for detection of such threats earlier than is currently possible. |
Whole genome-based population biology and epidemiological surveillance of Listeria monocytogenes.
Moura A , Criscuolo A , Pouseele H , Maury MM , Leclercq A , Tarr C , Bjorkman JT , Dallman T , Reimer A , Enouf V , Larsonneur E , Carleton H , Bracq-Dieye H , Katz LS , Jones L , Touchon M , Tourdjman M , Walker M , Stroika S , Cantinelli T , Chenal-Francisque V , Kucerova Z , Rocha EP , Nadon C , Grant K , Nielsen EM , Pot B , Gerner-Smidt P , Lecuit M , Brisse S . Nat Microbiol 2016 2 16185 Listeria monocytogenes (Lm) is a major human foodborne pathogen. Numerous Lm outbreaks have been reported worldwide and associated with a high case fatality rate, reinforcing the need for strongly coordinated surveillance and outbreak control. We developed a universally applicable genome-wide strain genotyping approach and investigated the population diversity of Lm using 1,696 isolates from diverse sources and geographical locations. We define, with unprecedented precision, the population structure of Lm, demonstrate the occurrence of international circulation of strains and reveal the extent of heterogeneity in virulence and stress resistance genomic features among clinical and food isolates. Using historical isolates, we show that the evolutionary rate of Lm from lineage I and lineage II is low ( approximately 2.5 x 10-7 substitutions per site per year, as inferred from the core genome) and that major sublineages (corresponding to so-called 'epidemic clones') are estimated to be at least 50-150 years old. This work demonstrates the urgent need to monitor Lm strains at the global level and provides the unified approach needed for global harmonization of Lm genome-based typing and population biology. |
What Makes a Bacterial Species Pathogenic?:Comparative Genomic Analysis of the Genus Leptospira.
Fouts DE , Matthias MA , Adhikarla H , Adler B , Amorim-Santos L , Berg DE , Bulach D , Buschiazzo A , Chang YF , Galloway RL , Haake DA , Haft DH , Hartskeerl R , Ko AI , Levett PN , Matsunaga J , Mechaly AE , Monk JM , Nascimento AL , Nelson KE , Palsson B , Peacock SJ , Picardeau M , Ricaldi JN , Thaipandungpanit J , Wunder EA Jr , Yang XF , Zhang JJ , Vinetz JM . PLoS Negl Trop Dis 2016 10 (2) e0004403 Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious Leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. Infectious Leptospira, comprised of pathogenic and intermediately pathogenic Leptospira, evolutionarily diverged from non-infectious, saprophytic Leptospira, as demonstrated by the following computational biology analyses: 1) the definitive taxonomy and evolutionary relatedness among all known Leptospira species; 2) genomically-predicted metabolic reconstructions that indicate novel adaptation of infectious Leptospira to mammals, including sialic acid biosynthesis, pathogen-specific porphyrin metabolism and the first-time demonstration of cobalamin (B12) autotrophy as a bacterial virulence factor; 3) CRISPR/Cas systems demonstrated only to be present in pathogenic Leptospira, suggesting a potential mechanism for this clade's refractoriness to gene targeting; 4) finding Leptospira pathogen-specific specialized protein secretion systems; 5) novel virulence-related genes/gene families such as the Virulence Modifying (VM) (PF07598 paralogs) proteins and pathogen-specific adhesins; 6) discovery of novel, pathogen-specific protein modification and secretion mechanisms including unique lipoprotein signal peptide motifs, Sec-independent twin arginine protein secretion motifs, and the absence of certain canonical signal recognition particle proteins from all Leptospira; and 7) and demonstration of infectious Leptospira-specific signal-responsive gene expression, motility and chemotaxis systems. By identifying large scale changes in infectious (pathogenic and intermediately pathogenic) vs. non-infectious Leptospira, this work provides new insights into the evolution of a genus of bacterial pathogens. This work will be a comprehensive roadmap for understanding leptospirosis pathogenesis. More generally, it provides new insights into mechanisms by which bacterial pathogens adapt to mammalian hosts. |
Accuracy of coverage survey recall following an integrated mass drug administration for Lymphatic Filariasis, Schistosomiasis, and soil-transmitted Helminthiasis
Budge PJ , Sognikin E , Akosa A , Mathieu EM , Deming M . PLoS Negl Trop Dis 2016 10 (1) e0004358 BACKGROUND: Achieving target coverage levels for mass drug administration (MDA) is essential to elimination and control efforts for several neglected tropical diseases (NTD). To ensure program goals are met, coverage reported by drug distributors may be validated through household coverage surveys that rely on respondent recall. This is the first study to assess accuracy in such surveys. METHODOLOGY/PRINCIPAL FINDINGS: Recall accuracy was tested in a series of coverage surveys conducted at 1, 6, and 12 months after an integrated MDA in Togo during which three drugs (albendazole, ivermectin, and praziquantel) were distributed. Drug distribution was observed during the MDA to ensure accurate recording of persons treated during the MDA. Information was obtained for 506, 1131, and 947 persons surveyed at 1, 6, and 12 months, respectively. Coverage (defined as the percentage of persons taking at least one of the MDA medications) within these groups was respectively 88.3%, 87.4%, and 80.0%, according to the treatment registers; it was 87.9%, 91.4% and 89.4%, according to survey responses. Concordance between respondents and registers on swallowing at least one pill was >95% at 1 month and >86% at 12 months; the lower concordance at 12 months was more likely due to difficulty matching survey respondents with the year-old treatment register rather than inaccurate responses. Respondents generally distinguished between pills similar in appearance; concordance for recall of which pills were taken was over 80% in each survey. SIGNIFICANCE: In this population, coverage surveys provided remarkably consistent coverage estimates for up to one year following an integrated MDA. It is not clear if similar consistency will be seen in other settings, however, these data suggest that in some settings coverage surveys might be conducted as much as one year following an MDA without compromising results. This might enable integration of post-MDA coverage measurement into large, multipurpose, periodic surveys, thereby conserving resources. |
The Global Trachoma Mapping Project: methodology of a 34-country population-based study
Solomon AW , Pavluck AL , Courtright P , Aboe A , Adamu L , Alemayehu W , Alemu M , Alexander ND , Kello AB , Bero B , Brooker SJ , Chu BK , Dejene M , Emerson PM , Flueckiger RM , Gadisa S , Gass K , Gebre T , Habtamu Z , Harvey E , Haslam D , King JD , Mesurier RL , Lewallen S , Lietman TM , MacArthur C , Mariotti SP , Massey A , Mathieu E , Mekasha A , Millar T , Mpyet C , Muñoz BE , Ngondi J , Ogden S , Pearce J , Sarah V , Sisay A , Smith JL , Taylor HR , Thomson J , West SK , Willis R , Bush S , Haddad D , Foster A . Ophthalmic Epidemiol 2015 22 (3) 214-25 PURPOSE: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. METHODS: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to "health district" size: populations of 100,000-250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h x c is calculated to facilitate recruitment of 1019 children aged 1-9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1-9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. RESULTS: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. CONCLUSION: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015. |
Spatial distribution of schistosomiasis and treatment needs in sub-Saharan Africa: a systematic review and geostatistical analysis
Lai YS , Biedermann P , Ekpo UF , Garba A , Mathieu E , Midzi N , Mwinzi P , N'Goran EK , Raso G , Assare RK , Sacko M , Schur N , Talla I , Tchuente LA , Toure S , Winkler MS , Utzinger J , Vounatsou P . Lancet Infect Dis 2015 15 (8) 927-40 BACKGROUND: Schistosomiasis affects more than 200 million individuals, mostly in sub-Saharan Africa, but empirical estimates of the disease burden in this region are unavailable. We used geostatistical modelling to produce high-resolution risk estimates of infection with Schistosoma spp and of the number of doses of praziquantel treatment needed to prevent morbidity at different administrative levels in 44 countries. METHODS: We did a systematic review to identify surveys including schistosomiasis prevalence data in sub-Saharan Africa via PubMed, ISI Web of Science, and African Journals Online, from inception to May 2, 2014, with no restriction of language, survey date, or study design. We used Bayesian geostatistical meta-analysis and rigorous variable selection to predict infection risk over a grid of 1 155 818 pixels at 5 x 5 km, on the basis of environmental and socioeconomic predictors and to calculate the number of doses of praziquantel needed for prevention of morbidity. FINDINGS: The literature search identified Schistosoma haematobium and Schistosoma mansoni surveys done in, respectively, 9318 and 9140 unique locations. Infection risk decreased from 2000 onwards, yet estimates suggest that 163 million (95% Bayesian credible interval [CrI] 155 million to 172 million; 18.5%, 17.6-19.5) of the sub-Saharan African population was infected in 2012. Mozambique had the highest prevalence of schistosomiasis in school-aged children (52.8%, 95% CrI 48.7-57.8). Low-risk countries (prevalence among school-aged children lower than 10%) included Burundi, Equatorial Guinea, Eritrea, and Rwanda. The numbers of doses of praziquantel needed per year were estimated to be 123 million (95% CrI 121 million to 125 million) for school-aged children and 247 million (239 million to 256 million) for the entire population. INTERPRETATION: Our results will inform policy makers about the number of treatments needed at different levels and will guide the spatial targeting of schistosomiasis control interventions. FUNDING: European Research Council, China Scholarship Council, UBS Optimus Foundation, and Swiss National Science Foundation. |
West African female sex workers in Mali: reduction in HIV prevalence and differences in risk profiles of sex workers of differing nationalities of origin
Trout CH , Dembele O , Diakite D , Bougoudogo F , Doumbia B , Mathieu J , Haidara A , Sangare A , Traore S , Burtner J , Cabral H , Messersmith LJ . J Acquir Immune Defic Syndr 2015 68 Suppl 2 S221-31 BACKGROUND: Female sex workers (FSW) in Mali are highly vulnerable to HIV. Their prevalence in 2009 was 9 times higher (24.2%) than that among pregnant women (2.7%). METHODS: Four Integrated HIV/sexually transmitted infection (STI) Surveillance and Behavioral Surveys among FSW in Mali (2000, 2003, 2006, and 2009) tracked demographic characteristics, behavior, and HIV and STI prevalence. Logistic regression using generalized estimating equations to control for the cluster effect identified factors associated with HIV-positive serostatus adjusting for potential confounding. RESULTS: Of 2430 FSW, 40.8% were Nigerian, 36.8% were Malian, and 22.4% were from other neighboring countries. Between 2003 and 2009, HIV prevalence dropped from 44.14% to 28.49% (P < 0.0001) among Malians, from 21.33% to 12.71% (P = 0.0082) among Nigerians, and from 43.42% to 33.67% (P = 0.0442) among "others." Between 2000 and 2009, condom availability increased (89.18%-99.3%; P < 0.0001) as did HIV testing (40%-75%; P < 0.0001). Consistent condom use with clients improved for Malians (72.3%-81.5%; P = 0.0092), but not among Nigerians (92.7%-90.94%; P = 0.8240) and "others" (88.9%-88.48%; P = 0.8452). Consistent condom use with boyfriends was low and improved only for Nigerians (9.8%-28.4%; P = 0.0003). Factors associated with HIV prevalence in the multivariate model were older age, study year (2003 and 2006), nationality, lack of education, mobility, STI symptoms, gonorrhea prevalence, and younger age at first sex. CONCLUSIONS: This study documents progress in the fight against HIV among FSW in Mali. The different vulnerabilities to HIV found for different nationality FSW should be considered in programming and future research. |
Spatial and temporal distribution of soil-transmitted helminth infection in sub-Saharan Africa: a systematic review and geostatistical meta-analysis
Karagiannis-Voules DA , Biedermann P , Ekpo UF , Garba A , Langer E , Mathieu E , Midzi N , Mwinzi P , Polderman AM , Raso G , Sacko M , Talla I , Tchuente LA , Toure S , Winkler MS , Utzinger J , Vounatsou P . Lancet Infect Dis 2014 15 (1) 74-84 BACKGROUND: Interest is growing in predictive risk mapping for neglected tropical diseases (NTDs), particularly to scale up preventive chemotherapy, surveillance, and elimination efforts. Soil-transmitted helminths (hookworm, Ascaris lumbricoides, and Trichuris trichiura) are the most widespread NTDs, but broad geographical analyses are scarce. We aimed to predict the spatial and temporal distribution of soil-transmitted helminth infections, including the number of infected people and treatment needs, across sub-Saharan Africa. METHODS: We systematically searched PubMed, Web of Knowledge, and African Journal Online from inception to Dec 31, 2013, without language restrictions, to identify georeferenced surveys. We extracted data from household surveys on sources of drinking water, sanitation, and women's level of education. Bayesian geostatistical models were used to align the data in space and estimate risk of with hookworm, A lumbricoides, and T trichiura over a grid of roughly 1 million pixels at a spatial resolution of 5 x 5 km. We calculated anthelmintic treatment needs on the basis of WHO guidelines (treatment of all school-aged children once per year where prevalence in this population is 20-50% or twice per year if prevalence is greater than 50%). FINDINGS: We identified 459 relevant survey reports that referenced 6040 unique locations. We estimate that the prevalence of hookworm, A lumbricoides, and T trichiura among school-aged children from 2000 onwards was 16.5%, 6.6%, and 4.4%. These estimates are between 52% and 74% lower than those in surveys done before 2000, and have become similar to values for the entire communities. We estimated that 126 million doses of anthelmintic treatments are required per year. INTERPRETATION: Patterns of soil-transmitted helminth infection in sub-Saharan Africa have changed and the prevalence of infection has declined substantially in this millennium, probably due to socioeconomic development and large-scale deworming programmes. The global control strategy should be reassessed, with emphasis given also to adults to progress towards local elimination. FUNDING: Swiss National Science Foundation and European Research Council. |
Final program evaluation methods and results of a National Lymphedema Management Program in Togo, West Africa
Ziperstein J , Dorkenoo M , Datagni M , Drexler N , Murphy M , Sodahlon Y , Mathieu E . J Epidemiol Glob Health 2014 4 (2) 125-33 In order to eliminate Lymphatic Filariasis (LF) as a public health problem, the World Health Assembly recommends an approach which includes interruption of transmission of infection and the alleviation of morbidity. In 2000, the Togolese National Program to Eliminate Lymphatic Filariasis (PNELF) started the annual mass drug administrations and in 2007, the program added a morbidity component for the management of lymphedema. This manuscript describes the methods of an evaluation aimed at assessing the strengths and weaknesses of the Togolese National Lymphedema Morbidity Program. The evaluation was conducted through in-depth interviews with stakeholders at each programmatic level. Interviews focused on message dissemination, health provider training, patient self-care practices, social dynamics, and program impact. The evaluation demonstrated that the program strengths include the standardization and in-depth training of health staff, dissemination of the program's treatment message, a positive change in the community's perception of lymphedema, and successful patient recruitment and training in care techniques. The lessons learned from this evaluation helped to improve Togo's program, but may also provide guidance and strategies for other countries desiring to develop a morbidity program. The methods of program evaluation described in this paper can serve as a model for monitoring components of other decentralized national health programs in low resource settings. |
Exploring innovative ways to conduct coverage surveys for neglected tropical diseases in Malawi, Mali, and Uganda
Woodhall DM , Mkwanda S , Dembele M , Lwanga H , Drexler N , Dubray C , Harris J , Worrell C , Mathieu E . Acta Trop 2014 132 119-24 Currently, a 30-cluster survey to monitor drug coverage after mass drug administration for neglected tropical diseases is the most common methodology used by control programs. We investigated alternative survey methodologies that could potentially provide an estimation of drug coverage. Three alternative survey methods (market, village chief, and religious leader) were conducted and compared to the 30-cluster method in Malawi, Mali, and Uganda. In Malawi, drug coverage for the 30-cluster, market, village chief, and religious leader methods were 66.8% (95% CI 60.3-73.4), 74.3%, 76.3%, and 77.8%, respectively. In Mali, results for round 1 were 62.6% (95% CI 54.4-70.7), 56.1%, 74.8%, and 83.2%, and 57.2% (95% CI 49.0-65.4), 54.5%, 72.2%, and 73.3%, respectively, for round 2. Uganda survey results were 65.7% (59.4-72.0), 43.7%, 67.2%, and 77.6% respectively. Further research is needed to test different coverage survey methodologies to determine which survey methods are the most scientifically rigorous and resource efficient. |
School-based mass distributions of mebendazole to control soil-transmitted helminthiasis in the Munshiganj and Lakshmipur districts of Bangladesh: an evaluation of the treatment monitoring process and knowledge, attitudes, and practices of the population
Hafiz I , Berhan M , Keller A , Haq R , Chesnaye N , Koporc K , Rahman M , Rahman S , Mathieu E . Acta Trop 2013 141 385-90 Bangladesh's national deworming program targets school-age children (SAC) through bi-annual school-based distributions of mebendazole. Qualitative and quantitative methods were applied to identify challenges related to treatment monitoring within the Munshiganj and Lakshmipur Districts of Bangladesh. Key stakeholder interviews identified several obstacles for successful treatment monitoring within these districts; ambiguity in defining the target population, variances in the methods used for compiling and reporting treatment data, and a general lack of financial and human resources. A treatment coverage cluster survey revealed that bi-annual primary school-based distributions proved to be an effective strategy in reaching school-attending SAC, with rates between 63.0%-73.3%, however, the WHO target of regular treatment of at least 75% of SAC has yet to be reached. Particularly low coverage was seen amongst non-school attending children (11.4%-14.3%), most likely due to the lack of national policy to effectively target this vulnerable group. Survey findings on water and sanitation coverage were impressive, with the majority of households and schools having access to latrines (98.6%-99.3%) and safe drinking water (98.2%-100%). The challenge now for the Bangladeshi control program is to achieve the WHO target of regular treatment of at least 75% of SAC at risk, irrespective of school-enrollment status. |
Ongoing surveillance for lymphatic filariasis in Togo: assessment of alternatives and nationwide reassessment of transmission status
Budge PJ , Dorkenoo AM , Sodahlon YK , Fasuyi OB , Mathieu E . Am J Trop Med Hyg 2013 90 (1) 89-95 Tremendous progress has been made to the goal of global elimination of lymphatic filariasis (LF) transmission by 2020. The number of endemic countries reducing LF transmission through mass drug administration continues to increase, and therefore, the need for effective post-intervention surveillance also continues to increase. Togo is the first sub-Saharan African country to implement LF surveillance, and it has 6 years of experience with this passive surveillance system. We herein report the results of a recent evaluation of the Togolese LF surveillance system, including an evaluation of blood donors as a surveillance population, and provide updated results of ongoing surveillance, including expansion in remote areas. Since implementation of LF surveillance in 2006, only three cases of positive Wuchereria bancrofti filaremia have been detected, suggesting that interruption of transmission has been sustained. Given the impracticality of validating the surveillance system in the absence of ongoing transmission, we confirmed the lack of transmission through a nationwide reassessment survey. |
It is possible: availability of lymphedema case management in each health facility in Togo: program description, evaluation, and lessons learned
Mathieu E , Dorkenoo AM , Morgah K , Datagni M , Cantey PT , Morgah K , Harvey K , Ziperstein J , Drexler N , Chapleau G , Sodahlon Y . Am J Trop Med Hyg 2013 89 (1) 16-22 Lymphatic filariasis (LF) is a vector-borne parasitic disease that can clinically manifest as disabling lymphedema. Although the LF elimination program aims to reduce disability and to interrupt transmission, there has been a scarcity of disease morbidity management programs, particularly on a national scale. This report describes the implementation of the first nationwide LF lymphedema management program. The program, which was initiated in Togo in 2007, focuses on patient behavioral change. Its goal is two-fold: to achieve a sustainable program on a national-scale, and to serve as a model for other countries. The program has five major components: 1) train at least one health staff in lymphedema care in each health facility in Togo; 2) inform people with a swollen leg that care is available at their dispensary; 3) train patients on self-care; 4) provide a support system to motivate patients to continue self-care by training community health workers or family members and providing in home follow-up; and 5) integrate lymphedema management into the curriculum for medical staff. The program achieved the inclusion of lymphedema management in the routine healthcare package. The evaluation after three years estimated that 79% of persons with a swollen leg in Togo were enrolled in the program. The adherence rate to the proposed World Health Organization treatment of washing, exercise, and leg elevation was more than 70% after three years of the program, resulting in a stabilization of the lymphedema stage and a slight decrease in reported acute attacks among program participants. Health staff and patients consider the program successful in reaching and educating the patients. After the external funding ended, the morbidity management program is maintained through routine Ministry of Health activities. |
A success story: Togo is moving toward becoming the first sub-Saharan African nation to eliminate lymphatic filariasis through mass drug administration and countrywide morbidity alleviation
Sodahlon YK , Dorkenoo AM , Morgah K , Nabiliou K , Agbo K , Miller R , Datagni M , Seim A , Mathieu E . PLoS Negl Trop Dis 2013 7 (4) e2080 Lymphatic filariasis (LF) is a debilitating vector-borne disease predominantly caused by the helminths Wuchereria bancrofti and Brugia malayi [1], [2]. Endemic in 72 countries, LF is responsible for 5.9 million DALYs lost and is implicated as the second leading cause of disability worldwide by the World Health Organization (WHO) [3]–[5]. Although 70% of those infected do not exhibit symptoms, almost all persons infected have subclinical damage to the lymphatic vessels [6], [7]. An estimated 40 million people are symptomatic with the predominant morbidities associated with LF: lymphedema and/or hydrocele [8]. | In recognition of the worldwide burden of LF, in 1997, the World Health Assembly passed the resolution WHA 50.29 calling for collaborative efforts by member states to eliminate the disease as a public health problem [9]. In 2000, the Global Programme to Eliminate Lymphatic Filariasis (GPELF) was formed in response to the WHA resolution and aimed to eliminate the disease by 2020. The program adopted a two-pronged strategy: (1) to interrupt transmission of the causal parasite and (2) to alleviate morbidities associated with the disease [10]. The two pillars of the GPELF's strategy form the basic framework for any successful LF program. | Togo is one of the 34 African countries endemic for lymphatic filariasis and is surrounded by the endemic countries of Benin, Ghana, and Burkina Faso [11]. The National Program to Eliminate Lymphatic Filariasis (NPELF) was founded in 2000 and is one of the few LF programs that address the dual goals of the global elimination program on a national scale. Togo is the first sub-Saharan country to achieve probable interruption of transmission and to move to the post-MDA surveillance phase as defined by the WHO [12]. Here we describe the elements that proved successful in the national strategy to address LF in Togo. |
Drug coverage surveys for neglected tropical diseases: 10 years of field experience
Worrell C , Mathieu E . Am J Trop Med Hyg 2012 87 (2) 216-22 Mass drug administration is one of the public health strategies recommended by the World Health Organization for the control and elimination of seven neglected tropical diseases (NTDs). Because adequate coverage is vital to achieve program goals, periodically conducting surveys to validate reported coverage to guide NTD programs is recommended. Over the past decade, the Centers for Disease Control and Prevention (CDC) and collaborators conducted more than 30 two-stage cluster household surveys across three continents. The questionnaires gathered coverage data and information relevant to improving NTD programs including NTD-related attitudes and practices. From the 37 coverage survey estimates obtained in those surveys, 73.3% indicated an over reporting of coverage, including all three that assessed school-based distributions. It took an average of 1 week to conduct a survey. Our experiences led us to conclude that coverage surveys are useful and feasible tools to ensure NTD elimination and control goals are reached. |
Nationwide integrated mapping of three neglected tropical diseases in Togo: countrywide implementation of a novel approach
Dorkenoo AM , Bronzan RN , Ayena KD , Anthony G , Agbo YM , Sognikin KS , Dogbe KS , Amza A , Sodahlon Y , Mathieu E . Trop Med Int Health 2012 17 (7) 896-903 OBJECTIVE: To conduct a nationwide integrated neglected tropical disease (NTD) prevalence survey to define the need for public health interventions using an innovative mapping protocol. METHODS: Two villages were selected in every peripheral health unit in endemic districts: 29 districts for schistosomiasis and STH, 15 of them for trachoma. In each village, 15 children aged 6-9 years at a randomly selected school were tested. An additional convenience sample of 35 children aged 1-5 years underwent an eye examination for trachoma. This integrated mapping was followed by a 20-cluster trachoma survey in each district that surpassed the WHO-defined threshold of 10% prevalence of trachomatous inflammation-follicular (TF). RESULTS: A total of 1096 villages were surveyed in <6 weeks. The district prevalence of schistosomiasis ranged from 2 to 49% and of STH from 5 to 70%, with prevalence at the village level ranging from 0 to 100% for both diseases. Two districts passed the threshold of 10% for active trachoma, but the cluster survey indicated this was because of misclassification bias and that the real prevalence was <1%. CONCLUSION: Results of this mapping were used by the MoH and partners to plan integrated mass drug administration (MDA). Mass drug administration for trachoma was not implemented as no district passed the threshold requiring public health intervention. |
A model-based tool to predict the propagation of infectious disease via airports
Hwang GM , Mahoney PJ , James JH , Lin GC , Berro AD , Keybl MA , Goedecke DM , Mathieu JJ , Wilson T . Travel Med Infect Dis 2012 10 (1) 32-42 Epidemics of novel or re-emerging infectious diseases have quickly spread globally via air travel, as highlighted by pandemic H1N1 influenza in 2009 (pH1N1). Federal, state, and local public health responders must be able to plan for and respond to these events at aviation points of entry. The emergence of a novel influenza virus and its spread to the United States were simulated for February 2009 from 55 international metropolitan areas using three basic reproduction numbers (R(0)): 1.53, 1.70, and 1.90. Empirical data from the pH1N1 virus were used to validate our SEIR model. Time to entry to the U.S. during the early stages of a prototypical novel communicable disease was predicted based on the aviation network patterns and the epidemiology of the disease. For example, approximately 96% of origins (R(0) of 1.53) propagated a disease into the U.S. in under 75 days, 90% of these origins propagated a disease in under 50 days. An R(0) of 1.53 reproduced the pH1NI observations. The ability to anticipate the rate and location of disease introduction into the U.S. provides greater opportunity to plan responses based on the scenario as it is unfolding. This simulation tool can aid public health officials to assess risk and leverage resources efficiently. |
The field-testing of a novel integrated mapping protocol for neglected tropical diseases
Pelletreau S , Nyaku M , Dembele M , Sarr B , Budge P , Ross R , Mathieu E . PLoS Negl Trop Dis 2011 5 (11) e1380 BACKGROUND: Vertical control and elimination programs focused on specific neglected tropical diseases (NTDs) can achieve notable success by reducing the prevalence and intensity of infection. However, many NTD-endemic countries have not been able to launch or scale-up programs because they lack the necessary baseline data for planning and advocacy. Each NTD program has its own mapping guidelines to collect missing data. Where geographic overlap among NTDs exists, an integrated mapping approach could result in significant resource savings. We developed and field-tested an innovative integrated NTD mapping protocol (Integrated Threshold Mapping (ITM) Methodology) for lymphatic filariasis (LF), trachoma, schistosomiasis and soil-transmitted helminths (STH). METHODOLOGY/PRINCIPAL FINDINGS: The protocol is designed to be resource-efficient, and its specific purpose is to determine whether a threshold to trigger public health interventions in an implementation unit has been attained. The protocol relies on World Health Organization (WHO) recommended indicators in the disease-specific age groups. For each disease, the sampling frame was the district, but for schistosomiasis, the sub-district rather than the ecological zone was used. We tested the protocol by comparing it to current WHO mapping methodologies for each of the targeted diseases in one district each in Mali and Senegal. Results were compared in terms of public health intervention, and feasibility, including cost. In this study, the ITM methodology reached the same conclusions as the WHO methodologies regarding the initiation of public health interventions for trachoma, LF and STH, but resulted in more targeted intervention recommendations for schistosomiasis. ITM was practical, feasible and demonstrated an overall cost saving compared with the standard, non-integrated, WHO methodologies. CONCLUSIONS/SIGNIFICANCE: This integrated mapping tool could facilitate the implementation of much-needed programs in endemic countries. |
A laboratory-based surveillance system for Wuchereria bancrofti in Togo: a practical model for resource-poor settings
Mathieu E , Dorkenoo A , Otogbe FK , Budge PJ , Sodahlon YK . Am J Trop Med Hyg 2011 84 (6) 988-93 One goal of the Global Program to Eliminate Lymphatic Filariasis (GAELF) is interruption of disease transmission through annual mass drug administration (MDA) in areas where LF prevalence is greater than 1%. After MDAs are completed, the World Health Organization (WHO) recommends a period of passive surveillance before final certification of LF elimination is achieved. Guidelines for such a surveillance system have yet to be developed. This paper describes a surveillance system launched in Togo in 2006. The system uses existing laboratories with technicians on call at night who, among other activities, prepare nocturnal thick blood smears for malaria diagnosis that can also be used for LF diagnosis. During its first 2 years (2006-2007), the system provided geographically disperse sampling nationwide, and 1 of 750 people residing in Togo was tested. Over the same period, the system detected two cases of LF, both from areas previously considered non-endemic. This system could be a cost-effective, sustainable model for WHO-mandated passive surveillance after cessation of MDA. |
Treatment coverage survey after a school-based mass distribution of mebendazole: Kampot Province; Cambodia
Chesnaye N , Sinuon M , Socheat D , Koporc K , Mathieu E . Acta Trop 2011 118 (1) 21-6 In efforts to reduce the global burden of soil transmitted helminth (STH) infections in school age children (SAC, 6-14 years old), Children Without Worms donates mebendazole to 8 countries with high prevalence of STH infections. Cambodia's national deworming program currently targets SAC through bi-annual school-based distributions of a single dose of mebendazole. A 30-cluster household survey was conducted in the rural province Kampot, to validate mebendazole treatment coverage in SAC and to assess the level of improved water supply and sanitation. Bi-annual primary school-based distributions proved to be an effective strategy in reaching school attending SAC, with treatment coverage rates between the 84.1% and 88.8%. However, significantly lower rates (23.3% - 48.8%) were seen among SAC not enrolled in primary schools. Often members of the most marginalized families of the community, they are particularly at risk of STH infection. Methods to reach these children need to be explored to avoid treatment inequities. |
Mapping, monitoring, and surveillance of neglected tropical diseases: towards a policy framework
Baker MC , Mathieu E , Fleming FM , Deming M , King JD , Garba A , Koroma JB , Bockarie M , Kabore A , Sankara DP , Molyneux DH . Lancet 2010 375 (9710) 231-8 As national programmes respond to the new opportunities presented for scaling up preventive chemotherapy programmes for the coadministration of drugs to target lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis, and trachoma, possible synergies between existing disease-specific policies and protocols need to be examined. In this report we compare present policies for mapping, monitoring, and surveillance for these diseases, drawing attention to both the challenges and opportunities for integration. Although full integration of all elements of mapping, monitoring, and surveillance strategies might not be feasible for the diseases targeted through the preventive chemotherapy approach, there are opportunities for integration, and we present examples of integrated strategies. Finally, if advantage is to be taken of scaled up interventions to address neglected tropical diseases, efforts to develop rapid, inexpensive, and easy-to-use methods, whether disease-specific or integrated, should be increased. We present a framework for development of an integrated monitoring and evaluation system that combines both integrated and disease-specific strategies. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Dec 02, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure