Joe Barber Jr, PhD
Mar 22, 2013
Hepatitis C virus (HCV) transmission appears to be rare among monogamous heterosexual couples, according to the findings of a cross-sectional study.
Norah A Terrault, MD, MPH, from the University of California San Francisco and colleagues published their findings in the March issue of Hepatology.
The authors note that the relationship between sexual activity and HCV transmission has been investigated previously. However, those data lack quantitative risk information that applies to couples in the United States because the studies were performed elsewhere.
"The few prospective cohort studies of monogamous heterosexual couples have reported incidence rates of HCV infection of 0%-0.6% per year in seronegative partners of subjects with chronic HCV infection," the authors write. "In cross-sectional studies, HCV prevalences among partners vary widely (0%-27%) but are < 5% in studies excluding partners with known percutaneous exposures."
In the current study, the authors recruited known anti-HCV–positive individuals and their heterosexual partners between January 2000 and May 2003. All couples had had a monogamous relationship for at least 36 months and at least 3 sexual encounters in the preceding 6 months. The exclusion criteria included a lack of sexual activity, prior organ transplantation, and hepatitis B virus or HIV co-infection.
Among the 500 partners of anti-HCV–positive participants included in the study, 20 (4%) were found to also be anti-HCV positive, 13 of whom were also HCV RNA positive. The 20 anti-HCV–positive couples included 9 couples with concordant genotypes/serotypes, 8 couples with discordant genotypes/serotypes, and 3 couples with indeterminate statuses.
Among the 9 couples with concordant genotypes/serotypes, 3 couples had highly related viral isolates, suggesting viral transmission between the couple. During 8377 person-years of follow-up in this study, the incidence of HCV transmission among couples was 3.6 per 10,000 person-years (95% confidence interval [CI], 0.0 - 7.7).
Additionally, the authors reported an estimated risk per sexual encounter of 1 per 380,000 (95% CI, 1/600,000 - 1/280,000) to 1 per 190,000 (95% CI, 1/1.03 million - 1/100,000).
The limitations of the study included its cross-sectional nature, potential recall bias, and low number of participants.
"In conclusion, HCV transmission by sex from chronically infected persons to their heterosexual partners in a long-term monogamous relationship likely occurs, but is a rare event," the authors write. "Our results provide a basis for specific counseling messages that clinicians can use with their patients. These messages should be qualified given the limitations of the sample size, but they support the current national recommendations that couples not change their sexual practices if they are in a monogamous heterosexual relationship."
The authors have disclosed no relevant financial relationships.
Hepatology. 2013;57:881-889. Abstract