ABSTRACT
It was observed in the city of Salvador, State of Bahia, the highest seroprevalence of human T cell lymphotropic virus type 1 (HTLV-1) infection in Brazil as demonstrated by national wide blood bank surveys. In this paper, we report results of an investigation of drug use and sexual behavior associated with HTLV-I infection among male and female injecting drug users (IDUs) in Salvador. A cross sectional study was conducted in the Historical District of Salvador from 1994 to 1996 (Projeto Brasil-Salvador) and 216 asymptomatic IDUs were selected using the snowball contact technique. Blood samples were collected for serological assays. Sera were screened for human immunodeficiency virus (HIV-1/2) and HTLV-I/II antibodies by ELISA and confirmed by Western blot. The overall prevalence of HTLV-I/II was 35.2 per cent (76/216). The seroprevalence of HTLV-I, HTLV-II and HIV-1 was for males 22 per cent, 11.3 per cent and 44.1 per cent and for females 46.2 per cent, 10.3 per cent and 74.4 per cent respectively. HTLV-I was identified in 72.4 per cent of HTLV positive IDUs. Variables which were significantly associated with HTLV-I infection among males included needles sharing practices, duration of injecting drug use, HIV-1 seropositivity and syphilis. Among women, duration of injecting drug use and syphilis were strongly associated with HTLV-I infection. Multivariate analysis did not change the direction of these associations. Sexual intercourse might play a more important role in HTLV-I infection among women than in men.