Prevalence of antibodies to hepatitis C virus (HCV) in haemophiliacs

The prevalence of 1) hepatitis C virus (HCV), an agent likely to be responsible for parenter transmitted hepatitis non-A, non-B, 2) hepatitis B virus (HBV) and 3) human immunodeficiency virus (HIV) infection was studied in 211 patients with clotting disorders(78% of the patients had residual factor activities of ≤2%). Of these patients 71% were positive for HBV markers and 44% for HIV markers. Using a new ELISA technique, 80% were anti-HCV-positive. The prevalence of anti-HCV was greater in patients with more severe clotting disorders and was related to the total amount of replacement therapy received; the prevalence was less in older patients. Seroconversion after a single exposure to dry heat-treated factor concentrates was documented in 3 patients 3–4 months after exposure.