Studies on schistosomiasis in Taiz Province, Yemen Arab Republic.

Infection with both urinary and intestinal schistosomiasis is prevalent with patchy distribution in Taiz Province, southwest Yemen Arab Republic. Schistosoma haematobium with a prevalence as high as 90% was found in the western, southern, and northern parts of the province. Among school children the overall prevalence was 37%. Infection rates did not differ significantly among various age and sex groups. Three species of Bulinus--B. beccarii, B. truncatus, and B. wrighti--have been found in the province, B. beccarii having the widest distribution and highest density. S. mansoni was found in most parts of the province. A 100% prevalence was found in some schools. The overall prevalence was 64% among school children and 68% among inhabitants of villages surveyed. Highest prevalence was found in the age group 10-20 years. Hepatosplenomegaly was prevalent among children in highly endemic areas. Biomphalaria pfeifferi, the intermediate host of S. mansoni, was found in most valleys.