1. Francis I. Proctor Foundation, University of California, San Francisco
2. Department of Ophthalmology, University of California, San Francisco
3. Programme National de Lutte Contre la Cecité, Niamey, Niger
4. Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
5. Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
6. Department of Epidemiology and Biostatistics, University of California, San Francisco
7. Institute for Global Health, University of California, San Francisco