About the Authors
Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
Kongwa Trachoma Project, Kongwa, Tanzania
The authors have declared that no competing interests exist.
Conceived and designed the experiments: ENS BM SKW. Performed the experiments: ENS JL HM SKW. Analyzed the data: ENS BM. Contributed reagents/materials/analysis tools: BM SKW. Wrote the paper: ENS JL HM BM SKW.