PREVALENCE OF HUMAN-IMMUNODEFICIENCY-VIRUS IN THE PATIENT POPULATION OF A SEXUALLY-TRANSMITTED DISEASE CLINIC - ASSOCIATION WITH SYPHILIS AND GONORRHEA

An unlinked seroprevalence survey of human immunodeficiency virus (HIV ) antibody was conducted using stored sera from all patients who atten ded the sexually transmitted disease (STD) clinic in Halifax, Nova Sco tia between 1980 and 1986. None of the sera collected from 584 patient s during 1980 were HIV positive. Of the 2867 patients who visited the clinic between 1981 and 1986, 27 (0.9%; 95% CI 0.6% to 1.2%) had the a ntibody. None of the 784 female patients were HIV seropositive. Of the 1,884 heterosexual men in the study, 5 (0.3%; 95% CI 0.1% to 0.5%) we re HIV seropositive, and 22 (11.1%; 95% CI 6.7% to 15.5%) of the 199 h omosexual men were HIV seropositive. There was a strong association be tween a history of syphilis and HIV antibody among heterosexual men (O R = 76.8; 95% CI 12.0 to 491.3; P = 0.001). Among homosexual men young er than 30 years of age, HIV infection was associated with a history o f syphilis (OR = 18.2; 95% CI 5.1 to 64.7; P = 0.035) and a history of gonorrhea (OR = 8.2; 95% CI 4.2 to 16.0; P = 0.001). The association between a history of gonorrhea and HIV infection was strongest among h omosexual men who had three or more sexual partners in the last month. These findings supplement existing evidence that STDs increase the li kelihood of HIV transmission.