BACKGROUND: Barombi Kotto, Cameroon serves as a reference location for assessing intervention strategies against Schistosoma haematobium. METHODS: As part of a pilot study, the whole community was treated with praziquantel, inclusive of pre-school-age children (PSAC) and their mothers. One year later, egg-patent infections were reassessed and water contact patterns of 12 pairs of PSAC and their mothers were measured with global positioning system (GPS) data loggers. RESULTS: A substantial reduction in general infection prevalence, from 44.8% to 12.2%, was observed but certain PSAC and mothers continued to have egg-patent infections. Analysis of GPS data demonstrated similar water contact levels between the child and mother groups, although certain individuals were numerical outliers. CONCLUSIONS: This study shows the potential of GPS data loggers to clarify the at-risk status of PSAC and mothers.