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

ABSTRACT

PIP: Unprotected homosexual intercourse and IV drug use were originally described as the predominant routes of HIV transmission in South America. Recent data, however, indicate that heterosexual transmission is becoming increasingly important in the region. With the goal of describing the changing patterns of risk factors for HIV-1 transmission, the authors collected prospectively data on demographic characteristics, referral patterns, and risk factors of patients at the time of first presentation to hospital services at an AIDS referral center in Porto Alegre, southern Brazil. The 357 male and 48 female patients presented over the period October 1985-September 1991. The overall HIV-related patient workload increased during the study period, as did the proportion of infected female patients. 44% of the men and 8% of women were self-referred. 36% of patients presented with symptomatic HIV disease and 19% with an AIDS-defining condition, with the men more likely than women to present with symptomatic disease. 23% of the infected men were bisexual; 24% of the heterosexually infected women had bisexual male partners. These findings suggest the importance of heterosexual HIV transmission in this area, with male bisexuals serving as an important route through which heterosexual females are being infected in the area. The data also suggest that heterosexual women in southern Brazil do not perceive themselves as being at risk for HIV-1 infection.