Risk behaviors for HIV-1 infection in Italian drug users: report from a multicenter study. First Drug User Multicenter Study Group.

In June 1987, a cross-sectional study was carried out on drug users attending public centers for drug dependency in Italy. Observed proportions of HIV seropositives among the 1,363 subjects from 34 public centers in 11 regions included in the study varied widely, with an overall seropositivity rate of 37%. Sharing syringes/needles, already used by other intravenous drug users, for preparing and injecting drugs represented independent risk factors for HIV-1 infection, while sexual lifestyle did not. Risk of infection increased with frequency of sharing equipment for preparing and for injecting drugs. Modification of risk behaviors in drug use was reported more frequently than in sexual lifestyle; both were significantly associated with knowledge of being seropositive for HIV-1 infection.