The efficiency of hepatitis C virus transmission by sexual activity remains controversial.
Dr Norah Terrault and colleagues conducted a cross-sectional study of hepatitis C virus-positive subjects, and their partners to estimate the risk for hepatitis C virus infection among monogamous heterosexual couples.
The team studied a total of 500 anti–hepatitis C virus-positive, human immunodeficiency virus–negative index subjects and their long-term heterosexual partners.
Couples were interviewed separately for lifetime risk factors for hepatitis C virus infection, within-couple sexual practices, and sharing of personal grooming items.
The doctors noted that blood samples were tested for anti-hepatitis C virus, hepatitis C virus RNA, and hepatitis C virus genotype and serotype.
Sequencing and phylogenetic analysis determined the relatedness of virus isolates among genotype-concordant couples.
The researchers assessed that the majority of hepatitis C virus-positive index subjects were non-Hispanic white, with a median age of 49 years and median of 15 years of sexual activity with their partners.
|The maximum incidence rate of HCV transmission by sex was 0.07% per year|
Overall, hepatitis C virus prevalence among partners was 4%, and 9 couples had concordant genotype/serotype.
The team doctors found that viral isolates in 3 couples were highly related, consistent with transmission of virus within the couple.
Based on 8,377 person-years of follow-up, the maximum incidence rate of hepatitis C virus transmission by sex was 0.07% per year or approximately one per 190,000 sexual contacts.
The team noted that no specific sexual practices were related to hepatitis C virus positivity among couples.
Dr Norah's team commented, "The results of this study provide quantifiable risk information for counseling long-term monogamous heterosexual couples in which one partner has chronic hepatitis C virus infection."
"In addition to the extremely low estimated risk for hepatitis C virus infection in sexual partners, the lack of association with specific sexual practices provides unambiguous and reassuring counseling messages."