1. Botswana Harvard AIDS Institute Partnership , Gaborone , Botswana
2. School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Gaborone , Botswana
3. Department of Applied Biological Sciences and Biotechnology, Faculty of Science and Technology, Midlands State University , Gweru , Zimbabwe
4. Department of Biological Sciences, Faculty of Sciences, University of Botswana, Gaborone , Botswana
5. Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health , Boston, Massachusetts , USA