1. MRC/UVRI Uganda Research Unit on AIDS, Uganda Virus Research Institute (UVRI), Entebbe, Uganda
2. Liverpool School of Tropical Medicine, Liverpool, United Kingdom
3. Infectious Diseases Insitute, Kampala, Uganda
4. University of Witwatersrand, Johannesburg, South Africa
5. Epidemiology and Genetics Unit, University of York, York, United Kingdom
6. London School of Tropical Medicine and Hygiene, London, United Kingdom