Changing patterns of HIV-1 transmission in southern Brazil 1985-1991

In order to describe the changing patterns of risk factors for HIV-1 transmission of patients using hospital services at an AIDS referral centre in Porto Alegre, southern Brazil, data on demographic characteristics, referral patterns and risk factors at time of first presentation were collected prospectively on 405 patients between October 1985 and September 1991. Overall HIV-related patient workload increased during the study period, as did the proportion of infected female patients seen (P < 0.05). Of all patients, 147 (36%) presented with symptomatic HIV disease and 77 (19%) presented with an AIDS defining condition; men were more likely to present with symptomatic disease than women. Approximately 156 (44%) of men were self-referred compared with 4 (8%) of the women (P < 0.0001). Of the 357 infected men, 82 (23%) were bisexuals; of the 26 heterosexually infected women, 7 (24%) had bisexual male partners. These data suggest the increasing importance of heterosexual HIV transmission in this hitherto 'low' prevalence area, with male bisexuals constituting an important route through which heterosexual females are being infected in this area. The data also suggest that heterosexual women in Southern Brazil do not perceive themselves to be at risk for HIV-1 infection.