Schistosomiasis in school-age children in Burkina Faso after a decade of preventive chemotherapy.

Hamado Ouedraogo,Tiba Pima,Fanny Yago-Wienne,Yaobi Zhang,Issouf Bamba,Mohamed Bagayan,François Drabo,Emily Toubali,Dramane Zongo

doi:10.2471/blt.15.161885

Abstract

ObjectiveTo assess the impact of a decade of biennial mass administration of praziquantel on schistosomiasis in school-age children in Burkina Faso.MethodsIn 2013, in a national assessment based on 22 sentinel sites, 3514 school children aged 7–11 years were checked for Schistosoma haematobium and Schistosoma mansoni infection by the examination of urine and stool samples, respectively. We analysed the observed prevalence and intensity of infections and compared these with the relevant results of earlier surveys in Burkina Faso.FindingsS. haematobium was detected in 287/3514 school children (adjusted prevalence: 8.76%, range across sentinel sites: 0.0–56.3%; median: 2.5%). The prevalence of S. haematobium infection was higher in the children from the Centre-Est, Est and Sahel regions than in those from Burkina Faso’s other eight regions with sentinel sites (P < 0.001). The adjusted arithmetic mean intensity of S. haematobium infection, among all children, was 6.0 eggs per 10 ml urine. Less than 1% of the children in six regions had heavy S. haematobium infections – i.e. at least 50 eggs per 10 ml urine – but such infections were detected in 8.75% (28/320) and 11.56% (37/320) of the children from the Centre-Est and Sahel regions, respectively. Schistosoma mansoni was only detected in two regions and 43 children – i.e. 1 (0.31%) of the 320 from Centre-Sud and 42 (8.75%) of the 480 from Hauts Bassins.ConclusionBy mass use of preventive chemotherapy, Burkina Faso may have eliminated schistosomiasis as a public health problem in eight regions and controlled schistosome-related morbidity in another three regions.

Highlights

It has been estimated that, in 2013, there were nearly 261 million people – including about 240 million in Africa – who required preventive chemotherapy because they were at risk of schistosome infection.[1]
In resolution WHA65.21, the World Health Assembly called on all countries with endemic schistosomiasis to intensify their control programmes and, where appropriate, to initiate campaigns for the elimination of schistosomiasis.[7]
The adjusted overall prevalence of S. haematobium infection was 8.76%, the prevalence of such infection ranged from 0.0% (0/160) to 56.3% (90/160) according to sentinel site

Summary

Introduction

Human schistosomiasis is endemic in 78 countries or territories.[1,2] It has been estimated that, in 2013, there were nearly 261 million people – including about 240 million in Africa – who required preventive chemotherapy because they were at risk of schistosome infection.[1]. Some form of human schistosomiasis is thought to be endemic in every one of the country’s 63 health districts.[9,10,11] urogenital schistosomiasis – caused by Schistosoma haematobium – occurs throughout the country, intestinal schistosomiasis – caused by Schistisoma mansoni – is mainly confined to the southwest of the country.[9,11] Surveys conducted before the 1980s, showed that the prevalence of S. haematobium was very high, with focal prevalence up to 100% of people surveyed in the eastern part of the country.[9] Over the same period, S. mansoni infection was found in up to 79% of people surveyed in the Hauts Bassins and Sud-Ouest regions.[9]

Methods

Results

Conclusion