Antibody to hepatitis C virus after a vapour-heated factor VIII concentrate. The Study Group of the Fondazione dell'Emofilia.

To evaluate whether or not clotting factor concentrates exposed to virucidal procedures transmitted hepatitis C, sera obtained in 1984-1986 from 27 previously untreated hemophiliacs infused with a vapour-heated factor VIII concentrate were tested retrospectively for the antibody to the hepatitis C virus (anti-HCV). A 2-year-old hemophiliac, negative for anti-HCV before administration of concentrate, seroconverted at week 12 and remained anti-HCV positive thereafter. Both his parents were anti-HCV negative and he had no other household contact. The patient had also become HBsAg positive at week 8 and had at the same time a marked elevation of alanine aminotransferase. His double infection with the hepatitis B and C viruses indicates that hot vapour was not completely effective in inactivating these viruses.