The relationship between morbidity and intensity of Schistosoma mansoni infection in a rural Zambian community.

Six hundred and ninety-three individuals from an area endemic for S. mansoni infection had parasitological and physical examinations done. A morbidity questionnaire was also administered to each participant. Among those with S. mansoni infection, there was significant increase in watery diarrhoea, bloody diarrhoea, blood in stool and hepatomegaly. The severity of the disease appears to be directly related to the egg load and therefore these results give further justification for treatment of high intensity age groups in community based chemotherapy programmes designed to reduce morbidity in endemic areas.