HPTN 075 is an observational cohort study. Participants will be accrued over six months at four sites in SSA using convenience sampling strategies, with no replacement for participants lost to follow-up. Each participant will be followed for 12 months, during which five study visits involving structured HIV behavioral assessments, medical examinations, and collection of biological samples will be conducted (including enrollment and quarterly follow-up visits). Participants who do not complete 12 months of follow-up will be contacted to explore reasons for no longer participating.