1. Division of Infectious Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
2. Medical Research Council/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
3. Center for Population and Development Studies, Harvard University, Cambridge, Massachusetts, USA
4. Department of Economics and Centre for Modern Indian Studies, University of Goettingen, Göttingen, Germany
5. Center for Global Health Research, Umea University, Umea, Sweden
6. Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA
7. Heidelberg Institute of Global Health, University of Heidelberg, Heidelberg, Germany
8. Africa Health Research Institute, Mtubatuba, South Africa.