The proposed study is a group-randomized trial to determine the frequency and treatment target of community-wide mass antibiotic treatment to eliminate trachoma. We will continue to monitor a sub-set of communities from our TANA study, in Goncha Siso Enese district of East Gojam Zone, Ethiopia. Here we evaluate how infection returns when antibiotics are discontinued, whether infection can be predictably eliminated, and whether infection can be prevented from returning with targeted treatment strategies: