Non-A, non-B hepatitis is common in hemophiliacs infused with clotting factors concentrates (1, 2). Using serum alanine aminotransferase (ALT) as a surrogate test for diagnosis, the proportion of hemophiliacs with chronic infection varies greatly, ranging from 20% (3) to 77% (4). Accurate estimation of chronic infection may be important clinically, because up to 20% of the patients may develop cirrhosis and hepatocellular carcinoma (5, 6). With the advent of a serologic assay for diagnosing infection with the hepatitis C virus (HCV), the major causative agent of blood-borne non-A, non-B hepatitis (7, 8), the real frequency of chronic infection in hemophiliacs