Soil-transmitted helminthiasis in four districts in Bangladesh: household cluster surveys of prevalence and intervention status.

BACKGROUND: In 2016, after 8 years of twice-annual nationwide preventive chemotherapy (PC) administration to school-age children (SAC), the Bangladesh Ministry of Health & Family Welfare (MOHFW) sought improved impact and intervention monitoring data to assess progress toward the newly adopted goal of eliminating soil-transmitted helminthiasis (STH) as a public health problem. METHODS: We surveyed four Bangladeshi districts between August and October 2017. We conducted a multi-stage, cluster-sample, household survey which produced equal-probability samples for preschool-age children (PSAC; 1-4 years), SAC (5-14 years), and adults (≥ 15 years). Standardized questionnaires were administered, using Android-based smart phones running an Open Data Kit application. Stool samples were collected and testing for STH prevalence and infection intensity used the Kato-Katz technique. RESULTS: In all, 4318 stool samples were collected from 7164 participants. Estimates of STH prevalence by risk group in three of the four surveyed districts ranged from 3.4 to 5.0%, all with upper, 1-sided 95% confidence limits < 10%. However, STH prevalence estimates in Sirajganj District ranged from 23.4 to 29.1%. Infections in that district were spatially focal; four of the 30 survey clusters had > 50% prevalence in at least one risk group. Among all tested specimens, Ascaris lumbricoides was the most common STH parasite [8.2% (n = 352)], followed by Trichuris trichiura [0.9% (n = 37)], and hookworm [0.6% (n = 27)]. In each district, PC coverage among SAC was above the 75% program target but did not exceed 45% among PSAC in any district. Improved sanitation at home, school, or work was over 90% in all districts. CONCLUSIONS: In the three low-prevalence districts, the MOHFW is considering decreasing the frequency of mass drug administration, per World Health Organization (WHO) guidelines. Also, the MOHFW will focus programmatic resources and supervisory efforts on Sirajganj District. Despite considering WHO guidance, the MOHFW will not expand PC administration to women of reproductive age partly due to the low prevalence of hookworm and T. trichiura, the STH parasites that contribute most to morbidity in that risk group. Data collected from surveys such as ours would help effectively guide future STH control efforts in Bangladesh and elsewhere.

National Malaria Control Program in Bangladesh: 2007-2010.

Malaria is a life-threatening disease caused by the plasmodium parasite, which is transmitted to people by the bites of infected mosquitoes. As elsewhere, this disease is also a major public health problem in Bangladesh. After independence, dichlorodiphenyltrichloroethane (DDT) use was banned in 1985, and the number of malaria cases began to increase. There were no control programs and inadequate funds, especially in the malaria-endemic areas; thus, malaria cases started to be epidemic in the 1990s. The global fund has been supporting the National Malaria Control Program (NMCP) in Bangladesh since the approval of the round 6 malaria proposal in 2006. This study aims to review the NMCP and changes in the burden of malaria in Bangladesh from 2007 to 2010. This is a descriptive retrospective study based on the secondary malaria surveillance data (cases and deaths) in 13 malaria-endemic districts, especially five selected districts, Chittagong, Cox's Bazar, Rangamati, Sylhet, and Mymensingh. A descriptive analysis was carried out to establish the incidence and mortality rate. From 2007 to 2010, a total of 264,293 confirmed malaria cases were notified from 13 malaria-endemic districts. More than 50% of the affected population was under the age group of ≥15 years (55.7%). Males had a higher risk of contracting of malaria than females, accounting for 53.5% of confirmed cases compared to 46.5% of females. Among the affected population, Plasmodium falciparum caused 85.6% of the total incidence. Rangamati has the highest incidence rate among the five districts. Although the incidence was high, death was declining: in 2007, it was 228, and in 2010, it was 37. The finding shows that while the incidence is still high, mortality is decreasing, therefore, it can be said that the NMCP is functioning. However, to fully achieve the goal of eliminating malaria, the NMCP requires efforts to develop new strategies and maintain a high-quality surveillance and reporting system.

Developing the first national database and map of lymphatic filariasis clinical cases in Bangladesh: Another step closer to the elimination goals.

BACKGROUND: The Bangladesh Lymphatic Filariasis (LF) Elimination Programme has made significant progress in interrupting transmission through mass drug administration (MDA) and has now focussed its efforts on scaling up managing morbidity and preventing disability (MMDP) activities to deliver the minimum package of care to people affected by LF clinical conditions. This paper highlights the Bangladesh LF Programme's success in conducting a large-scale cross-sectional survey to determine the number of people affected by lymphoedema and hydrocoele, which enabled clinical risk maps to be developed for targeted interventions across the 34 endemic districts (19 high endemic; 15 low endemic). METHODOLOGY/PRINCIPAL FINDINGS: In the 19 high endemic districts, 8,145 community clinic staff were trained to identify and report patients in their catchment area. In the 15 low endemic districts, a team of 10 trained field assistants conducted active case finding with cases reported via a SMS mHealth tool. Disease burden and prevalence maps were developed, with morbidity hotspots identified at sub-district level based on a combination of the highest prevalence rates per 100,000 and case-density rates per square kilometre (km2). The relationship between morbidity and baseline microfilaria (mf) prevalence was also examined. In total 43,678 cases were identified in the 19 high endemic districts; 30,616 limb lymphoedema (70.1%; female 55.3%), 12,824 hydrocoele (29.4%), and 238 breast/female genital swelling (0.5%). Rangpur Division reported the highest cases numbers and prevalence of lymphoedema (26,781 cases, 195 per 100,000) and hydrocoele (11661 cases, 169.6 per 100,000), with lymphoedema predominately affecting females (n = 21,652). Rangpur and Lalmonirhat Districts reported the highest case numbers (n = 11,199), and prevalence (569 per 100,000) respectively, with five overlapping lymphoedema and hydrocoele sub-district hotspots. In the 15 low endemic districts, 732 cases were identified; 661 lymphoedema (90.2%; female 39.6%), 56 hydrocoele (7.8%), and 15 both conditions (2.0%). Spearman's correlation analysis found morbidity and mf prevalence significantly positively correlated (r = 0.904; p<0.01). CONCLUSIONS/SIGNIFICANCE: The Bangladesh LF Programme has developed one of the largest, most comprehensive country databases on LF clinical conditions in the world. It provides an essential database for health workers to identify local morbidity hotspots, deliver the minimum package of care, and address the dossier elimination requirements.

The significant scale up and success of Transmission Assessment Surveys 'TAS' for endgame surveillance of lymphatic filariasis in Bangladesh: One step closer to the elimination goal of 2020.

BACKGROUND: Bangladesh had one of the highest burdens of lymphatic filariasis (LF) at the start of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) with an estimated 70 million people at risk of infection across 34 districts. In total 19 districts required mass drug administration (MDA) to interrupt transmission, and 15 districts were considered low endemic. Since 2001, the National LF Programme has implemented MDA, reduced prevalence, and been able to scale up the WHO standard Transmission Assessment Survey (TAS) across all endemic districts as part of its endgame surveillance strategy. This paper presents TAS results, highlighting the momentous geographical reduction in risk of LF and its contribution to the global elimination target of 2020. METHODOLOGY/PRINCIPAL FINDINGS: The TAS assessed primary school children for the presence of LF antigenaemia in each district (known as an evaluation unit-EU), using a defined critical cut-off threshold (or 'pass') that indicates interruption of transmission. Since 2011, a total of 59 TAS have been conducted in 26 EUs across the 19 endemic MDA districts (99,148 students tested from 1,801 schools), and 22 TAS in the 15 low endemic non-MDA districts (36,932 students tested from 663 schools). All endemic MDA districts passed TAS, except in Rangpur which required two further rounds of MDA. In total 112 students (male n = 59; female n = 53), predominately from the northern region of the country were found to be antigenaemia positive, indicating a recent or current infection. However, the distribution was geographically sparse, with only two small focal areas showing potential evidence of persistent transmission. CONCLUSIONS/SIGNIFICANCE: This is the largest scale up of TAS surveillance activities reported in any of the 73 LF endemic countries in the world. Bangladesh is now considered to have very low or no risk of LF infection after 15 years of programmatic activities, and is on track to meet elimination targets. However, it will be essential that the LF Programme continues to develop and maintain a comprehensive surveillance strategy that is integrated into the health infrastructure and ongoing programmes to ensure cost-effectiveness and sustainability.