Notes on the use of urine-CCA dipsticks for detection of intestinal schistosomiasis in preschool children

Urine-dipstick diagnostic tests that detect schistosome circulating cathodic antigen (CCA) have the potential to provide more sensitive and rapid testing for intestinal schistosomiasis in field-based surveys; this is especially so when examining preschool children, from whom it may be difficult to obtain consecutive stool samples. To assess the performance of urine dipsticks, 569 preschool children from four villages along the shore of Lake Albert, Uganda, were screened for Schistosoma mansoni by Kato-Katz (K-K) examination of a single stool sample and CCA urine dipsticks. The prevalence of infection was 32.2% by K-K and 40.0% by CCA tests. Sensitivity and specificity were influenced by whether 'trace' results from the CCA test were characterised as positive or negative for infection with S. mansoni; ambiguities around this issue need to be resolved. Nevertheless, the CCA test showed particular promise for routine epidemiological screening in this setting.