Diagnostic and cost comparisons of a questionnaire against a chemical reagent strip test in identifying high risk communities for Schistosoma haematobium infection in northern Zambia.

A comparative study was conducted in northern Zambia in order to compare both the economical and diagnostic performance of a questionnaire with that of the chemical reagent strip test in diagnosing urinary schistosomiasis with a view to replacing the more economically expensive reagent strip test with the questionnaire in the identification of high risk communities. A total of 57 schools participated in the study and each school was considered as a community. Among the symptoms and conditions of blood in urine, pain when passing urine and bilharzia for urinary schistosomiasis, blood in the urine was the best predictor for urinary schistosomiasis with 73.9 pc (95 pc CI 56.0 to 91.9 pc) sensitivity, 82.4 pc (95 pc CI 69.5 to 95.2 pc) specificity and 78.9 pc (95 pc CI 68.4 to 89.5 pc) diagnostic efficiency in the identification of schools with high levels of infection. A diagnostic questionnaire for urinary schistosomiasis was two times cheaper than the reagent strip test in economical terms. The questionnaire approach in identifying high risk communities for urinary schistosomiasis is promising and should be tried in other endemic areas.