Mass drug administration significantly reduces infection of Schistosoma mansoni and hookworm in school children in the national control program in Sierra Leone

Mary H Hodges,Emanuel Nyorkor,Mustapha Sonnie,Yaobi Zhang,Anna Warmsley,Jusufu Paye,Nsa Dada,Momodu M Bangura

doi:10.1186/1471-2334-12-16

Abstract

BackgroundThe first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program. To evaluate the impact of the treatment regimen, a cross-sectional sentinel site survey was conducted 6 months post-MDA.MethodsFifteen sentinel schools from six highly endemic districts (according to data from national and pre-MDA surveys) with Schistosoma mansoni affecting over 50% of the population, and moderate to high prevalence of hookworms (> 20%). Approximately 30 children aged 9-14 years were selected from each school and stool samples (one per student) were examined by the Kato-Katz method.ResultsThe overall prevalence (and intensity) in these sentinel sites pre-MDA of S. mansoni was 69.0% (170.8 epg), hookworm: 41.7% (71.7 epg), Ascaris lumbricoides: 1.8% and Trichuris trichiura: 3.8%. Six months post MDA, the findings were S. mansoni: 38.2% (47.3 epg) and hookworm: 14.5% (8.7 epg), representing a reduction from pre-MDA levels of 44.6% (65.2%) and 72.3% (87.9%) respectively. The proportion of children who were moderately or heavily infected with S. mansoni fell from 35.6% pre MDA to 9.9% post MDA.ConclusionsSignificant reduction in S. mansoni and hookworm infection was achieved by this first round MDA in school-going children in Sierra Leone. This reduction in infection burden can potentially contribute to a reduction of morbidity, such as anaemia, in these children.

Highlights

The first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program
This study reports the prevalence and intensity of S. masoni and soil-transmitted helminthiasis (STH) in school children 9-14 years of age in these endemic sentinel sites 6 months after treatment with praziquantel and mebendazole and compares these with the pre-MDA levels
To minimize the sideeffects of praziquantel treatment in this first-ever MDA, a special school feeding program for children to be treated was arranged with the support of United States Agency for International Development (USAID), as in rural settings in Sierra Leone, many children go to school in the morning without a meal and some may not have eaten the night before

Summary

Introduction

The first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program. Worm infections in children can result in stunting, wasting, diminished physical fitness, impaired memory and cognition [5,8] which combine to reduce educational performance, school attendance, future adult productivity, wage-earning capacity [5,9] and Gross National Productivity. These infections have direct and indirect effects on malaria and HIV/AIDS in developing countries where they are co-endemic [10].

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Results

Conclusion