Transmission of human parvovirus B19 by coagulation factor concentrates.

The prevalence of antibody to human parvovirus B19 was determined in 86 children with congenital bleeding disorders. Forty-seven of 53 boys (89%) receiving non-heat-treated factor VIII or prothrombin complex concentrates were anti-B19 IgG positive compared with 38% of their age-matched controls and 48% of children treated with cryoprecipitate. Acute B19 virus infection occurred in 2 boys 3-4 weeks after they had received the same batch of commercial factor VIII concentrate. Of 11 susceptible children who had only received heat-treated National Health Service factor VIII concentrate (8Y), 1 acquired anti-B19 IgG. This suggests that 8Y heat-treated concentrate has a much reduced risk of transmitting B19 virus and, by implication, other less heat-stable viruses such as human immunodeficiency virus.