1. Department of Social and Environmental Health Research; London School of Hygiene and Tropical Medicine; London UK
2. Department of Social Science; UCL Institute of Education; University College London; London UK
3. Department of Epidemiology; Gillings School of Global Public Health; University of North Carolina; Chapel Hill NC USA
4. Wits RHI; University of the Witwatersrand; Johannesburg South Africa
5. School of Health and Society; University of Wollongong; Wollongong NSW Australia
6. Medical Research Council/Wits University Rural Public Health and Health Transitions Research Unit (Agincourt); School of Public Health; Faculty of Health Sciences; University of the Witwatersrand; Johannesburg South Africa
7. Centre for Global Health Research; Umeå University; Umeå Sweden
8. INDEPTH Network; Accra Ghana
9. Department of Pathology; Johns Hopkins University School of Medicine; Baltimore MD USA
10. Division of Infectious Diseases; Johns Hopkins University School of Medicine; Baltimore MD USA
11. Division of Intramural Research; National Institute of Allergy and Infectious Diseases; National Institutes of Health; Bethesda MD USA