Affiliation: | 1. London School of Hygiene and Tropical Medicine, London, United Kingdom.; 2. Kenya Medical Research Institute-Wellcome Trust Research Programme, Nairobi, Kenya.; 3. George Washington University, Washington, District of Columbia, United States of America.; 4. Sabin Vaccine Institute, Washington, District of Columbia, United States of America.; 5. The World Bank, Washington, District of Columbia, United States of America.;Yale School of Public Health, United States of America |