Blood Donor Screening for West NiIe Virus in Oklahoma and Its Contribution to Disease Surveillance, 2003 -2013

Upon recognition that West Nile virus (WNV) was transmissible by transfusion, universal testing of blood donors by nucleic acid testing (NAT) was initiated in 2003. A retrospective review of 2003-2013 blood donor records and public health surveillance data in Oklahoma was undertaken to determine the percentage of WNV-positive blood donors who developed clinical symptoms post-donation and to examine the incidence and timing of WNV viremic donors in the context of WNV disease reported statewide. Among all WNV NAT-positive blood donors, 19% had self-described symptoms consistent with WNV disease. A viremic blood donor was the seasonal index case of WNV transmission in Oklahoma during one year [2006] of the study period. Blood donors remain an important surveillance component for epidemiologic monitoring of WNV in Oklahoma.