Identification of a site for a cohort study on natural history of HIV infection in Ethiopia

A cross-sectional survey was carried out in a sugar estate in central Ethio pia to identify a subgroup for a cohort study on the natural history of HIV infection. HIV prevalence was 2.8% (95% confidence interval [CI], 1.7%-3.9 %) in 957 adults aged 15 to 54 years randomly selected for the initial surv ey. A follow-up survey including only factory workers of the estate aged 18 to 45 years (n = 280)showed a higher HIV prevalence in male factory worker s (n = 262) compared With the male estate workers of the same age of the in itial survey (n = 484; 8.8% venus 3.1%; p < .05). Factors independently ass ociated with HIV infection in male factory workers were number of lifetime sexual partners, positive syphilis serology, higher income, and absence of travel outside the residential area. Among male estate workers,only older a ge was associated with HIV infection. Both factory workers and male estate workers were stable residents and were willing to participate in a long-ter m study on HIV/AIDS. However, because of the higher HIV prevalence in facto ry workers and the higher prevalence of behaviors associated with an increa sed risk for HIV infection, factory workers were selected for the long-term cohort study on the natural history of HIV infection.