1. Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
2. Botswana Harvard AIDS Institute, Gaborone, Botswana.
3. Department of Biological Sciences, University of Botswana, Gaborone, Botswana.
4. Vaccine and Infectious Diseases Division, Fred Hutchinson Cancer Research Center, Seattle, Washington.
5. Faculty of Health Sciences, Simon Fraser University, Burnaby, Canada.
6. British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada.