West Nile virus infection transmitted by blood transfusion

BACKGROUND: A patient with transfusion-transmitted West Nile virus (WNV) infection confirmed by viral culture of a blood component is described. A 24-year-old female with severe postpartum hemorrhage developed fever, chills, headache, and generalized malaise after transfusion of 18 units of blood components; a serum sample and the cerebrospinal fluid tested positive for the presence of WNV IgM antibodies. An investigation was initiated to determine a possible association between transfusion and WNV infection. STUDY DESIGN AND METHODS: Blood donors were assessed for recent infection through questionnaires and WNV testing of serum samples. Whole-blood retention segments and untransfused blood components were sent to the CDC to test for the presence of WNV through PCR (TaqMan, Applied Biosystems), IgM ELISA, plaque reduction neutralization testing, and viral culture. RESULTS: Three of 15 available donor retention segments were WNV PCR-positive. WNV was recovered from one associated blood component. The implicated donor was symptomatic near the time of donation; serology confirmed WNV IgM seroconversion. CONCLUSION: Seroconversion of a symptomatic donor, the presence of viral genetic material in an associated whole-blood retention segment, and recovery of WNV from an associated component provides compelling evidence for transfusion-acquired infection. This report has important implications for blood safety.