Prevalence of Schistosoma mansoni infection in two municipalities of the State of Alagoas, Brazil

Introduction: Preliminary studies indicate a probable schistosomiasis expansion in Alagoas. This work analyzes the occurrence of Schistosoma mansoni in students from two municipalities, located in the Mundau and Paraiba rivers basins. Methods: The study group consisted of 690 students in the urban area, aged between seven and 15 years. A standardized socio-(e)conomic questionnaire was filled out and parasitological tests were used to diagnosis schistosomiasis (Lutz and Kato methods). Positive cases were treated and students and their families were lectured about health education. Results: The Schistosoma mansoni prevalence was 24.9%. The association between schistosomiasis and other parasitic diseases was significant in relation to trichuriasis (p <0.05). Only 50% of infected children lived in brick homes with sanitation and public water supply. Among them, 48.1% used to go usually to the water collections and 55.8% of them knew rivers snails. The concordance analysis between the Lutz and Kato methods showed disagreement in 54.2%, with greater sensitivity for the Lutz technique (76.4%). Conclusions: The indices obtained characterize the municipalities as hyperendemic areas, because prevalence rates over 5% are considered high according to the World Health Organization. The high prevalence observed here is also two times higher than that reported by the Brazilian Schistosomiasis Program Control.