Intrafamilial transmission of hepatitis C virus infection

Background: The role of intrafamilial HCV transmission is still controversial. Methods: An overall sample of 2856 consecutive HCV-infected patients was studied. All index cases were interviewed to identify potential risk factors for transmission and underwent the following tests: HBsAg, anti-HBc, HIV, and, qualitative HCV-RNA and genotyping. Results: Coinfection with HBsAg was recorded in 4.7%, and with HIV in 2.6% of the HCV-infected index cases. Anti-HCV was detected in 2.1% of the members of their original families, and in 13.8% of 2662 sexual partners. The overall rate of infection for offspring was 2.3%, but the risk was significantly higher when the index case was female. The risk for sexual partners was significantly higher when the risk factor for the index case was intravenous drug (IVD) use rather than blood transfusion. Logistic regression analysis showed that female gender and drug addiction in sexual partners of index case were independent factors significantly associated with HCV transmission to sexual partners. Conclusions: Among all family members of index cases, sexual partners of IVD users were at greatest risk of HCV infection. Sexual transmission may not be the main route of transmission though, since IVD use in the sexual partners themselves was independently associated with HCV infection.