Evaluation of an improved approach using residences of schistosomiasis-positive school children to identify carriers in an area of low endemicity.

School children were used as indicators for the identification of schistosomiasis-positive family members in a area of low endemicity. This study was designed to improve current schistosomiasis control programs by applying this strategy to identify schistosomiasis-positive individuals in a more efficient way. The initial prevalence among school children was 8.6%. However, the prevalence among the family members of these school children increased to 15.5%. In contrast to these findings the prevalence in family members of schistosomiasis-negative school children was 3.8%. Although the applied methodology showed a relatively low sensitivity (50.0%), the high negative predictive value (87.7%) indicates that a few positive family members of school children with a negative stool result will be missed. This shows that this method of evaluation could be a strategy for a more efficient and cheaper identification of schistosomiasis-positive individuals in areas of low endemicity.