Seroepidemiologic study of hepatitis C virus in sexually transmitted disease risk groups.

To identify the importance of heterosexual activity as a possible route for the transmission of the hepatitis C virus (HCV), a screening of antibodies against HCV (anti-HCV) was performed in 200 sexually transmitted disease patients with different risks for incurring genital infections as well as in 100 registered prostitutes. Out of all 300 persons tested, 14 cases of HCV infection were detected. Anti-HCV was present in 3 of the prostitutes and in 11 of the STD patients. Evaluating known risk factors, such as intravenous drug use or blood transfusion, 6 out of the 11 STD patients and all of the prostitutes in whom anti-HCV was present were intravenous drug users and exhibited highly promiscuous behavior. Intravenous drug use was the probable means of acquisition in 9 of the 14 subjects in whom anti-HCV was present, and homosexual promiscuous behavior was assumed to be the means of acquisition in another 2 subjects. In heterosexual patients engaging in high-risk behavior (high number of sexual partners and genital infections), the exclusion of intravenous drug use decreased the prevalence of anti-HCV from 12.1% to 4.1%, demonstrating no significant increase from the prevalence among low-risk persons. Most of the patients were screened for STDs, such as syphilis, Neisseria gonorrhoeae, Chlamydia trachomatis, human immunodeficiency virus (HIV), hepatitis B virus (HBV), trichomoniasis, and yeast infections. The highest rate of coinfection with anti-HCV was found in patients with serologic evidence of an HIV infection (50%).(ABSTRACT TRUNCATED AT 250 WORDS)