Socioeconomic status and risk of HIV-1, syphilis and hepatitis B infection among sex workers in São Paulo State, Brazil. Instituto Adolfo Lutz Study Group.

Objectives: To determine how HIV risk behavior and the prevalences of sexually transmitted diseases vary according to socioeconomic status and city among sex workers in São Paulo State, Brazil.

Subjects And Methods: A cross-sectional study of 600 female sex workers (100 of a higher socioeconomic status and 100 of a lower socioeconomic status in each city) was conducted in the cities of São Paulo, Campinas and Santos. HIV risk behavior was assessed by questionnaire; serological tests were administered to assess prior exposure to HIV-1, syphilis and hepatitis B.

Results: Only statistically significant (P < 0.05) findings are reported here. Compared to those with a higher socioeconomic status, sex workers with a lower socioeconomic status worked longer hours each day (9.6 versus 7.9), had more clients per day (5.4 versus 2.6) and had fewer episodes of intercourse per client per encounter (1.1 versus 1.4). Levels of condom use for vaginal, anal and oral sex were significantly higher in Santos than in São Paulo or Campinas. Twenty-three per cent of the women said they feared violence if they insisted that their clients wear condoms; 74% voiced similar fears regarding their non-client sexual partners. Overall, 11% of sex workers were positive for exposure to HIV-1, 45% for syphilis and 39% for hepatitis B. Those with a lower socioeconomic status were more likely than those with a higher socioeconomic status to be infected with HIV-1 (17 versus 4%), syphilis (66 versus 24%) and hepatitis B (52 versus 26%), but there were no differences in prevalence rates by city.

Conclusions: These data demonstrate substantial heterogeneity in HIV risk behavior and the prevalence of HIV-1 and other sexually transmitted diseases among sex workers in São Paulo State, many of which were related to differences in socioeconomic status. Interventions to prevent HIV transmission among sex workers must be tailored to the local environment and, in particular, to the socioeconomic status of these workers.