1. School of Health Sciences, Monash University, 144 Peter Road, Ruimsig, Johannesburg 1794, South Africa
2. School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Park Town, Johannesburg 2193, South Africa
3. HIV/AIDS, STI and TB (HAST) Research Program, Human Sciences Research Council, 134 Pretorius Street, Pretoria 002, South Africa
4. Department of Health Studies, University of South Africa (UNISA), 1 Preller Street, Muckleneuk, Pretoria 0002, South Africa