An updated atlas of human helminth infections: the example of East Africa.

BACKGROUND: Reliable and updated maps of helminth (worm) infection distributions are essential to target control strategies to those populations in greatest need. Although many surveys have been conducted in endemic countries, the data are rarely available in a form that is accessible to policy makers and the managers of public health programmes. This is especially true in sub-Saharan Africa, where empirical data are seldom in the public domain. In an attempt to address the paucity of geographical information on helminth risk, this article describes the development of an updated global atlas of human helminth infection, showing the example of East Africa. METHODS: Empirical, cross-sectional estimates of infection prevalence conducted since 1980 were identified using electronic and manual search strategies of published and unpublished sources. A number of inclusion criteria were imposed for identified information, which was extracted into a standardized database. Details of survey population, diagnostic methods, sample size and numbers infected with schistosomes and soil-transmitted helminths were recorded. A unique identifier linked each record to an electronic copy of the source document, in portable document format. An attempt was made to identify the geographical location of each record using standardized geolocation procedures and the assembled data were incorporated into a geographical information system. RESULTS: At the time of writing, over 2,748 prevalence surveys were identified through multiple search strategies. Of these, 2,612 were able to be geolocated and mapped. More than half (58%) of included surveys were from grey literature or unpublished sources, underlining the importance of reviewing in-country sources. 66% of all surveys were conducted since 2000. Comprehensive, countrywide data are available for Burundi, Rwanda and Uganda. In contrast, information for Kenya and Tanzania is typically clustered in specific regions of the country, with few records from areas with very low population density and/or environmental conditions which are unfavourable for helminth transmission. Information is presented on the prevalence and geographical distribution for the major helminth species. CONCLUSION: For all five countries, the information assembled in the current atlas provides the most reliable, up-to-date and comprehensive source of data on the distribution of common helminth infections to guide the rational implementation of control efforts

Population-based survey of active trachoma in 11 districts of Burundi.

PURPOSE: To establish that trachoma is a public health problem in Burundi, and to provide baseline data on the prevalence of active trachoma and unclean faces prior to the commencement of trachoma elimination activities in endemic districts. METHODS: For each of 11 pilot districts, eight collines (hills) (estimated population generally 1000-8000) were selected at random using a population-proportional-to-size technique; from each selected colline, one sous-colline (of which there are generally 3-5 per colline) was selected at random by simple random draw. In each selected sous-colline, all available 1-9-year-old children were examined for clinical signs of trachoma, and for signs of an unclean face (defined as eye discharge, nose discharge and/or presence of one or more flies on the face during the time taken to examine the eyes). RESULTS: A mean of 230 children were examined per sous-colline (range 44-600); in all, 20,659 children were examined in 90 sous-collines of 11 districts. (In one district, 10 rather than eight sous-collines were selected.) In three contiguous districts (Buhiga, Nyabikere and Muyinga) in the country's north-east, the prevalence of the sign "trachomatous inflammation-follicular" (TF) in 1-9-year-olds was >10%. In nine districts, the prevalence of unclean faces was >10%. CONCLUSION: Trachoma is a public health problem in Burundi. Implementation of trachoma control activities is indicated in at least Buhiga, Nyabikere and Muyinga. Further work should be carried out to establish the likely backlog of unoperated trachomatous trichiasis

Coendemicity map in Burundi communes in 2010 for trachoma, onchocerciasis, schistosomiasis, and soil-transmitted helminth infections.

<p>Coendemicity in Burundi after results obtained from mapping surveys performed in 2007–2010. Colours and patterns indicate presence of disease in cases of onchocerciasis or prevalence of TF below 10% (low) or above ≥10% (high) in cases of trachoma. For schistosomiasis and soil-transmitted helminth infections, colours and patterns indicate disease prevalence, which was estimated via predictive risk maps created with the epidemiological and geospatial integrated approach. In detail, for schistosomiasis, low, moderate, and high indicate prevalence <10%, between 10% and 50%, and above 50%, respectively. For soil-transmitted helminth infections, low, moderate, and high indicate prevalence below 20%, between 20% and 50%, and above 50%, respectively. Abbreviations: Schisto, schistosomiasis; Oncho, onchocerciasis.</p

Drug distribution strategies adopted during the NTD programme for trachoma, onchocerciasis, schistosomiasis, and soil-transmitted helminth infections.

<p>Distribution channels, drugs (or drug packages), target groups, and endemic areas where drugs were delivered are shown in this figure. Children below 1 year of age and women at the first trimester of pregnancy received vaccinations during the MCHW but no preventive chemotherapy. Adults above 15 years of age in areas at risk of schistosomiasis but not endemic for onchocerciasis (or trachoma) were not targeted by any of the health campaigns and did not receive PZQ. * Considering that no test was available to confirm pregnancy in the first 3 months, women often could not receive ALB if uncertain about their status.</p

Evolution of the NTD prevention and control programme in Burundi.

<p>Evolution of the NTD prevention and control programme in Burundi.</p

Programme coverage for STHs.

<p>Means and standard deviations (SD) are calculated based on district programme coverage reported by the Ministry of Health for each district after every MDA. Programme coverage was calculated as the proportion of a specific group of individuals that received ALB over the total number of individuals within that group in the implementing unit deemed at risk of STH infection <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0002684#pntd.0002684-World8" target="_blank">[26]</a>.</p><p>In December 2008 and June 2009, women were not treated. Geographic coverage for ALB was always 100%.</p>a<p>In 2007 coverage was reported by province (n = 17).</p>b<p>Districts Nyabikere, Gahombo, Busini, and Vumbi did not exist as administrative units in 2008–2009 (n = 41).</p>c<p>New administrative system included 45 districts (n = 45).</p>d<p>Women's coverage was not reported in June 2011 for Kayanza district.</p

Control of Neglected Tropical Diseases in Burundi: Partnerships, Achievements, Challenges, and Lessons Learned after Four Years of Programme Implementation

<p>Control of Neglected Tropical Diseases in Burundi: Partnerships, Achievements, Challenges, and Lessons Learned after Four Years of Programme Implementation</p

Individuals treated for schistosomiasis and STHs in each MDA in Burundi.

<p>* In December 2008 and June 2009, women did not receive treatment.</p

Countrywide reassessment of Schistosoma mansoni infection in Burundi using a urine-circulating cathodic antigen rapid test: informing the national control program

Following implementation of the national control program, a reassessment of Schistosoma mansoni prevalence was conducted in Burundi to determine the feasibility of moving toward elimination. A countrywide cluster-randomized cross-sectional study was performed in May 2014. At least 25 schools were sampled from each of five eco-epidemiological risk zones for schistosomiasis. Fifty randomly selected children 13-14 years of age per school were included for a single urine-circulating cathodic antigen (CCA) rapid test and, in a subset of schools, for duplicate Kato-Katz slide preparation from a single stool sample. A total of 17,331 children from 347 schools were tested using CCA. The overall prevalence of S. mansoni infection, when CCA trace results were considered negative, was 13.5% (zone range [zr] = 4.6-17.8%), and when CCA trace results were considered positive, it was 42.8% (zr = 34.3-49.9%). In 170 schools, prevalence of this infection determined using Kato-Katz method was 1.5% (zr ==0-2.7%). The overall mean intensity of S. mansoni infection determined using Kato-Katz was 0.85 eggs per gram (standard deviation = 10.86). A majority of schools (84%) were classified as non-endemic (prevalence = 0) using Kato-Katz; however, a similar proportion of schools were classified as endemic when CCA trace results were considered negative (85%) and nearly all (98%) were endemic when CCA trace results were considered positive. The findings of this nationwide reassessment using a CCA rapid test indicate that Schistosoma infection is still widespread in Burundi, although its average intensity is probably low. Further evidence is now needed to determine the association between CCA rapid test positivity and low-intensity disease transmission

Partners in the NTD control programme in Burundi.

<p>Partners in the NTD control programme in Burundi.</p