Prevalence of antibodies to human immunodeficiency virus type 1 and condom use among outpatients at a sexually transmitted disease clinic in Rome.

To assess the prevalence of HIV-1 infection and study selected risk factors among patients attending a clinic for sexually transmitted diseases in Rome, 1442 outpatients seen consecutively between 20 February and 12 December 1989 were anonymously tested for anti-HIV-1. An evaluation of the trend of the HIV-1 infection was attempted by comparing the results of the present study with those obtained from a similar sample studied in 1986 in the same clinic. The overall estimated prevalence of anti-HIV-1 was 1.2% among heterosexual non-drug user subjects and 16.1% among homosexual or bisexual men. The anti-HIV-1 seropositivity was significantly higher in heterosexual subjects who reported sexual contact with intravenous drug users, as compared with those who did not report such exposure (12.5% vs 0.8%, p less than 0.005). Comparing the present data with those of a study conducted in 1986 in the same clinic, a lower prevalence of anti-HIV-1 was found among heterosexual subjects (1.2% in 1989 vs 6.0% in 1986, p less than 0.001). The availability after 1986 of several outpatient facilities attracting seropositive subjects and a change in the sexual behaviour of anti-HIV-1 positive subjects could explain this finding. Twenty percent of the heterosexual subjects and 62% of the homosexual or bisexual men reported consistent use of condoms.(ABSTRACT TRUNCATED AT 250 WORDS)