To the Editor:
We read with interest the article by Terrault et al. in HEPATOLOGY entitled “Sexual Transmission of HCV Among Monogamous Heterosexual Couples: The HCV Partners Study.” The authors conducted a cross-sectional study of hepatitis C virus (HCV)-positive persons and their partners to estimate the risk for HCV infection among monogamous heterosexual couples. Their findings based on 8,377 person-years of follow-up demonstrated that the maximum incidence rate of HCV transmission by sex was 0.07% per year (95% confidence interval [CI]: 0.01, 0.13) or ∼1 per 190,000 sexual contacts and that no specific sexual practices were related to HCV-positivity among couples.
Large longitudinal studies of HCV-serodiscordant heterosexual couples have not yielded significant evidence of sexual transmission, so condom use for the prevention of HCV transmission has not been recommended for vaginal intercourse between monogamous HCV-serodiscordant sexual partners.[2, 3]
We agree with part of their conclusions on counseling messages. Indeed, the estimated risk for HCV infection in sexual partners is extremely low. However, we and others demonstrated that anal sexual practice significantly increases the risk of HCV transmission. Relative to vaginal intercourse, anal intercourse is a major cause of abrasions of mucosa, leading to the possibility of anal transmission. The high incidence of acute HCV infection among men who have sex with men (MSM) with human immunodeficiency virus (HIV) infection is mainly due to unprotected anal intercourse and the transmission depends on disruption of a barrier and exposure to infected fluids, usually blood. Also, certain sexual practices involving trauma of the rectal mucosa have been discussed as relevant risk factors among MSM.[6, 7] Coinfections with bacterial sexually transmitted infections (STIs), especially ulcerative STIs such as syphilis or lymphogranuloma venereum, have also been proposed as risk factors for HCV transmission among HIV-positive MSM. Fisting was highly correlated with use of sex toys, group sex, and bleeding in a cross-sectional study from Urbanus et al.
Terrault et al. found no association with specific sexual practices. They reported that vaginal intercourse during menses and anal intercourse (≥1 occasion) were reported by 65.2% and 30.4% of couples, respectively. Condom use during vaginal intercourse was reported by 29.9% of couples and condom use decreased over time for vaginal and anal intercourse. However, the results on sexual practices were declarative and may have some bias.
In conclusion, although HCV transmission by sexual activity remains low in long-term monogamous HCV heterosexual couples, strict recommendations should be made regarding sexual practices, that is, protected anal intercourse and protected vaginal intercourse during menstruations.
PHILIPPE HALFON, PHARM, M.D., PH.D.
Hôpital Ambroise Paré, Laboratoire Alphabio, Marseille, France