Antibody to a hepatitis C virus related protein among patients at high risk for hepatitis B.

Anti-HCV prevalence in treated hemophiliacs, their heterosexual partners, intravenous drug addicts and homosexual men was studied. In hemophiliacs and many of the intravenous drug addicts, greater than or equal to 2 sera drawn 1-18 or 1-17 years apart were available. Anti-HCV testing was performed by ELISA (Ortho). Among patients with severe and moderate hemophilia A, 87% (98/112) were positive for anti-HCV at least once and among patients with severe and moderate hemophilia B, 83% (24/29) were positive for anti-HCV. Seroconversion to anti-HCV was observed in 21% of hemophilia patients. In hemophilia A, HCV infection generally occurred during the first years of life and in hemophilia B somewhat later. Loss of anti-HCV antibody was seen in 12% (17 patients). The rest, 54% (76 patients) were seropositive in first and last samples. All 12 tested spouses to anti-HCV positive men were anti-HCV negative. 80% of the drug addicts (137/172) were seropositive for anti-HCV. In those with greater than 1 serum tested, 8% were consistently negative and 68% consistently positive. 21% seroconverted to anti-HCV while 3% lost antibody. 10% (22/211) of homosexual men were anti-HCV positive. Intravenous transmission of HCV thus seemed highly efficient whereas sexual transmission was much less efficient.