Investigation of porcine parvovirus among persons with hemophilia receiving Hyate : C porcine factor VIII concentrate

BACKGROUND: Porcine clotting factor has been used for more than 15 years to treat severe bleeding episodes in persons with hemophilia who have antibod ies to human clotting factor. In 1996, QC procedures revealed for the first time the presence of porcine parvovirus (PPV) in the product. This report describes an investigation to determine the extent of product contamination and to evaluate past recipients of porcine clotting factor (Hyate:C, Speyw ood Biopharm) for evidence of PPV infection. STUDY DESIGN AND METHODS: Stored specimens from 22 lots of previously relea sed Hyate:C were tested for the presence of PPV DNA by PCR and nested PCR a ssays. Serum specimens from 98 recipients of Hyate:C and 24 controls who di d not receive Hyate:C were tested for PPV antibodies by an immunofluorescen ce assay. RESULTS: PPV DNA was detected in product from 21 of the 22 lots of Hyate:C, primarily by nested PCR testing, In contrast, none of the serum specimens from the 98 Hyate:C recipients tested positive for PPV IgG antibodies. CONCLUSION: The risk of human disease from percutaneous exposure to low lev els of PPV seems to be low. Nevertheless, the theoretical risk of human inf ection with PPV has led to manufacturing changes, including PCR screening o f all porcine plasma, which are designed to eliminate this risk.