Spatial clustering of ocular chlamydial infection over time following treatment, among households in a village in Tanzania.

Purpose: To observe the spatial distribution of households with high loads of ocular chlamydia infection in children, before and after mass treatment with azithromycin to determine whether there exists spatial clustering of households with high loads of infection and the spatial scale of the clustering.

Methods: All residents of a village in Tanzania were invited to participate in the study. A global positioning system unit recorded the location of each house.