Human parvovirus B19 in young male patients with hemophilia A: associations with treatment product exposure and joint range‐of‐motion limitation

Abstract
BACKGROUND:  To evaluate the risk of human parvovirus B19 (B19) transmission in recombinant antihemophilic factor, the seroprevalence among 798 two‐ to seven‐year‐old boys with hemophilia was compared. Also, data collected on joints were used to assess relations between B19 serostatus and joint range‐of‐motion (ROM) limitation.STUDY DESIGN AND METHODS:  Staff at US hemophilia treatment centers collected data on product exposures and ROM of 10 joints and provided blood specimens as part of blood safety surveillance. Blood was tested for immunoglobulin G anti‐B19. Associations between B19 seropositivity and treatment products and joint ROM limitations were examined in multivariate analyses.RESULTS:  Compared to children who received no product, the odds of B19 seropositivity were 0.8 (p = 0.5), 1.9 (p = 0.05), and 7.6 (p < 0.001) for those children who received recombinant antihemophilic factor only, both recombinant antihemophilic factor and plasma‐derived factor, and plasma‐derived factor only, respectively. Children who were anti‐B19 positive had an average 8° less overall ROM (p = 0.002) than those who were B19 antibody negative after adjustment for other risk factors.CONCLUSION:  The risk of B19 transmission by recombinant antihemophilic factor is low. Previous B19 infection is associated with ROM limitations in very young male patients with hemophilia. Virus inactivation techniques effective against B19 and other nonenveloped viruses are needed.