1. Institute of Infectious Disease and Molecular Medicine and Wellcome Centre for Infectious Disease Research, University of Cape Town, Cape Town, South Africa
2. Rollins School of Public Health and School of Medicine, Emory University, Atlanta, GA
3. Rollins School of Public Health and School of Medicine, Emory University, Atlanta, GA, Bureau for Global Health, US Agency for International Development, Washington, DC, USA, , Email: helen.cox@uct.ac.za