Schistosomiasis in infants and preschool-aged children: Infection in a single Schistosoma haematobium and a mixed S. haematobium-S. mansoni foci of Niger

Abstract

The burden of schistosomiasis in infants and preschool-aged children and their mothers is poorly known. We carried out a cross-sectional epidemiological survey in two villages in Niger: Falmado is endemic for Schistosoma haematobium only, whereas a mixed S. haematobium-S. mansoni focus has been reported from Diambala. The survey examined 282 children (149 girls, 133 boys, average age: 2.6 years) and 224 mothers (average age: 30.1 years). For S. haematobium diagnosis, two urine samples obtained on consecutive days were subjected to the standard urine filtration method. Additionally, macro- and microhaematuria were determined. The diagnosis of S. mansoni was based on a single stool sample with duplicate Kato-Katz thick smears. In Diambala, a standardised, pre-tested questionnaire was administered to mothers, which recorded demographic data, treatment history with anthelminthic drugs, household sanitation and water supply, and bathing practices for their children. Prevalence of egg-patent S. haematobium infections among young children and their mothers was respectively 50.5% and 55.6%, in Falmado, and 60.5% and 72.2% in Diambala. The prevalence of S. mansoni infection in Diambala was 43.8% among children and 52.1% in mothers. Mixed egg-patent infections of S. haematobium and S. mansoni were revealed in 28.6% of the children and 37.3% of the mothers. Questionnaire data showed that 69.8% of the children were accompanied by their mothers to schistosomiasis transmission sites before they were 1 year of age, and that three-quarter of the mothers used water directly drawn from the irrigation canals to wash their children. To conclude, a substantive proportion of children below the age of 5 years had egg-patent schistosomiasis, inclusive of co-infection with S. haematobium and S. mansoni. In the context of schistosomiasis control, more attention should be paid on preschool-aged children and women of childbearing age, so that they can benefit from preventive chemotherapy, which in turn might increase effective coverage of those infected.