1. Social sciences, Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine (MRC/UVRI&LSHTM), Uganda Research Unit, Entebbe, Uganda
2. Department of Social and Behavioural Sciences, Rakai Health Sciences Program (RHSP), Kalisizo, Uganda
3. School of Medicine, Johns Hopkins University, Baltimore, MD, USA
4. Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, UK