Prevalence of Trachoma in Northern Benin: Results from 11 Population-Based Prevalence Surveys Covering 26 Districts.

AIMS: We sought to evaluate trachoma prevalence in all suspected-endemic areas of Benin. METHODS: We conducted population-based surveys covering 26 districts grouped into 11 evaluation units (EUs), using a two-stage, systematic and random, cluster sampling design powered at EU level. In each EU, 23 villages were systematically selected with population proportional to size; 30 households were selected from each village using compact segment sampling. In selected households, we examined all consenting residents aged one year or above for trichiasis, trachomatous inflammation - follicular (TF), and trachomatous inflammation - intense. We calculated the EU-level backlog of trichiasis and delineated the ophthalmic workforce in each EU using local interviews and telephone surveys. RESULTS: At EU-level, the TF prevalence in 1-9-year-olds ranged from 1.9 to 24.0%, with four EUs (incorporating eight districts) demonstrating prevalences ≥5%. The prevalence of trichiasis in adults aged 15+ years ranged from 0.1 to 1.9%. In nine EUs (incorporating 19 districts), the trichiasis prevalence in adults was ≥0.2%. An estimated 11,457 people have trichiasis in an area served by eight ophthalmic clinical officers. CONCLUSION: In northern Benin, over 8000 people need surgery or other interventions for trichiasis to reach the trichiasis elimination threshold prevalence in each EU, and just over one million people need a combination of antibiotics, facial cleanliness and environmental improvement for the purposes of trachoma's elimination as a public health problem. The current distribution of ophthalmic clinical officers does not match surgical needs

Baseline trachoma prevalence in Guinea: Results of national trachoma mapping in 31 health districts.

BACKGROUND: Based on previous studies, historical records and risk factors, trachoma was suspected to be endemic in 31 health districts (HDs) in Guinea. To facilitate planning for the elimination of trachoma as a public health problem, national trachoma surveys were conducted between 2011 and 2016 to determine the prevalence of trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT) in all 31 endemic HDs. METHODOLOGY/PRINCIPAL FINDINGS: A total of 27 cross-sectional surveys were conducted, each using two-stage cluster sampling (one survey in 2011 covered five HDs). Children aged 1-9 years and adults aged ≥15 years were examined for TF and TT, respectively, using the World Health Organization (WHO) simplified grading system. Indicators of household access to water, sanitation and hygiene (WASH) were also collected. A total of 100,051 people from 13,725 households of 556 clusters were examined, of whom 44,899 were male and 55,152 were female. 44,209 children aged 1-9-years and 48,745 adults aged ≥15 years were examined. The adjusted prevalence of TF varied between 1.0% (95%CI: 0.6-1.5%) to 41.8% (95%CI: 39.4-44.2%), while the adjusted prevalence of TT ranged from 0.0% (95%CI: 0.0-0.2%) to 2.8% (95%CI: 2.3-3.5%) in the 27 surveys. In all, 18 HDs had a TF prevalence ≥5% in children aged 1-9 years and 21 HDs had a TT prevalence ≥0.2% in adults aged ≥15 years. There were an estimated 32,737 (95% CI: 19,986-57,811) individuals with TT living in surveyed HDs at the time of surveys. CONCLUSIONS/SIGNIFICANCE: Trachoma is a public health problem in Guinea. 18 HDs required intervention with at least one round of mass drug administration and an estimated 32,737 persons required TT surgery in the country. The results provided clear evidence for Guinea to plan for national trachoma elimination

Trachoma in the Democratic Republic of the Congo: Results of 46 Baseline Prevalence Surveys Conducted with the Global Trachoma Mapping Project.

PURPOSE: Trachoma was suspected to be endemic in parts of the Democratic Republic of the Congo (DRC). We aimed to estimate prevalences of trachomatous inflammation-follicular (TF), trichiasis, and water and sanitation (WASH) indicators in suspected-endemic Health Zones. METHODS: A population-based prevalence survey was undertaken in each of 46 Health Zones across nine provinces of DRC, using Global Trachoma Mapping Project methods. A two-stage cluster random sampling design was used in each Health Zone, whereby 25 villages (clusters) and 30 households per cluster were sampled. Consenting eligible participants (children aged 1-9 years and adults aged ≥15 years) were examined for trachoma by GTMP-certified graders; households were assessed for access to WASH. RESULTS: A total of 32,758 households were surveyed, and 141,853 participants (98.2% of those enumerated) were examined for trachoma. Health Zone-level TF prevalence in 1-9-year-olds ranged from 1.9-41.6%. Among people aged ≥15 years, trichiasis prevalences ranged from 0.02-5.1% (95% CI 3.3-6.8). TF prevalence in 1-9-year-olds was ≥5% in 30 Health Zones, while trichiasis prevalence was ≥0.2% in 37 Health Zones. CONCLUSION: Trachoma is a public health problem in 39 of 46 Health Zones surveyed. To meet elimination targets, 37 Health Zones require expanded trichiasis surgery services while 30 health zones require antibiotics, facial cleanliness and environmental improvement interventions. Survey data suggest that trachoma is widespread: further surveys are warranted

Schistosomiasis and Soil Transmitted Helminths Distribution in Benin: A Baseline Prevalence Survey in 30 Districts

<div><p>In 2013, Benin developed strategies to control neglected tropical diseases and one of the first step was the disease mapping of the entire country in order to identify endemic districts of schistosomiasis and soil transmitted helminths (STH). This study was carried out in 30 of the 77 districts of Benin. Of these 30 districts 22 were previously treated for Lymphatic Filariasis (LF) using the Ivermectin and Albendazole combination. In each district, five schools were selected and 50 children aged 8 to 14 years were sampled in each school, making a total of 250 children sampled in the district. The schools were selected mainly according to their proximity to lakes or any bodies of water that were likely to have been used by the children. Samples of faeces and urine were collected from each pupil. Urinary schistosomiasis was identified using the urine filtration technique while STH and intestinal schistosomiasis were identified through the Kato Katz method. Overall a total of 7500 pupils were surveyed across 150 schools with a gender ratio of 1:1. Hookworm was identified in all 30 districts with a prevalence ranging from 1.2% (95%CI: 0.0–2.5) to 60% (95%CI: 53.9–66.1). <i>Ascaris lumbricoides</i> was detected in 19 districts with a prevalence rate between 1% (95%CI: 0.0–2.2) and 39% (95%CI: 32.9–45.0). In addition to these common STH, <i>Trichuris trichiura</i>, <i>Enterobius vermicularis</i> and <i>Strongyloides stercoralis</i> were found at low prevalence. Only 16 districts were endemic to <i>Schistosoma mansoni</i>, while 29 districts were endemic to <i>S</i>. <i>haematobium</i>. The <i>S</i>. <i>haematobium</i> prevalence ranged from 0.8% (95% CI: 0.0–1.9) to 56% (95% CI: 50.2–62.5) while the prevalence of <i>S</i>. <i>mansoni</i> varied from 0.4% (95%CI: 0.0–1.2) to 46% (95% CI: 39.8–52.2). The 22 districts, where LF was successfully eliminated, still require mass drug administration (MDA) of albendazole indicating that school-based MDA would be needed even after LF elimination in districts co-endemic to LF and STH in Benin.</p></div

Comparison of the prevalence of the most common STH (Hookworm) to <i>S</i>.<i>haematobium</i>.

<p><b>X2: Chi-square value of comparison of Hookworm and S. haematobium prevalence within each district. p-value: p value of comparison of Hookworm and S. haematobium prevalence within each district.</b> In each column, the letter “a”, “b” or “c” indicates that the prevalence sharing similar letter are not significantly different while those sharing different letters are significantly different.</p

Comparison of the average prevalence of <i>S</i>. <i>haematobium</i> in each department.

<p>Comparison of the average prevalence of <i>S</i>. <i>haematobium</i> in each department.</p

Comparison of the average prevalence of Hookworm in each department.

<p>On the chart, the department sharing similar letter are not significantly different. Those sharing different letters indicate a significant difference [p<0.0001]</p

Prevalence rate and intensity of other soil transmitted helminths found in the 30 districts mapped in 2014 in Benin.

<p>N: Total number of positive samples out the total (250) examined in each commune, 95%CI: 95% confidence interval for prevalence. For <i>E</i>. <i>vermicularis</i> and <i>T</i>. <i>trichiura intensity</i>: Light: 1-999EPG; Moderate: 1000-9999EPG; High: ≥10000EPG. For S. <i>stercoralis</i> Light: 1-800EPG; Moderate: 801-1200EPG; High: >1200EPG.</p

Comparison of the average prevalence of <i>S</i>. <i>mansoni</i> in each department.

<p>Comparison of the average prevalence of <i>S</i>. <i>mansoni</i> in each department.</p