Evaluation of selected symptoms in the diagnosis of Schistosoma mansoni infection.

Data on morbidity associated with S. mansoni infection was gathered using a questionnaire before parasitological screening was done in a rural Zambian community. Blood in stool, bloody diarrhoea and watery diarrhoea were found to be significantly associated with S. mansoni infection. Levels of sensitivity, specificity and predictive values were calculated for each symptom. On the basis of results obtained we speculate that these symptoms could be used by peripheral health workers in making early diagnosis of the disease in the absence of laboratory diagnostic tests.