Fifty heterosexual partners out of 50 patients (index cases) without confirmed or probable risk factors of parenteral transmission by HCV were studied from 1/1997 to 1/2001. The index cases were HCV Ab (+) (EIA 3rd Abbott and PCR + by RT-nested PCR). The couples with probable or confirmed risk factors of parenteral transmission were strictly excluded. No case of HCV infection was found, suggesting that sexual via wouldn't be a direct transmission of HCV.