Urinary Bilharziasis among Nigerian school children: a study in the Agulu Lake Basin, Anambra State of Nigeria.

Following the observation of cases of haematuria among a secondary school population near Agulu Lake, an area not previously regarded as an endemic focus of schistosomiasis, a field study on urinary Bilharziasis was carried out among primary school pupils in the three towns surrounding Agulu Lake which was suspected to be the source of the infection. It was discovered that the area is an endemic focus of Schistosoma haematobium with prevalence rates ranging up to 77.6% among the primary school populations in one school. Schools in the parts of the three towns, (Agulu, Nri and Adazi) closest to the Lake proved to be highly endemic with Agulu having the highest prevalence rate (47.2%), followed by Nri 29.9% and Adazi 2.4%. Males were affected slightly more than females and the prevalence increased steadily in both sexes with age in the primary school population studied (5-15 years). Most of the cases were asymptomatic (54.6%). Macroscopic haematuria was noted to be the most sensitive criteria for clinical diagnosis. Interview of the subjects suggested that other areas outside the zone might also be involved.