Genome-wide real-time PCR for West Nile virus reduces the false-negative rate and facilitates new strain discovery.

West Nile virus (WNV) causes significant morbidity and mortality worldwide. Transplant and transfusion recipients as well as the elderly are particularly at risk. WNV shows strain variation from season to season and from locale to locale. This poses a significant problem for diagnosis. Most assays use a single primer pair to detect WNV by QPCR, and can fail to detect novel stains. To overcome this limitation, a genome-wide, multiple primer-based real-time QPCR assay was developed for WNV. The same assay can be used for quantitation, viral variant discovery as well as for amplification of the entire viral genome using a single annealing temperature. It improves upon routine diagnosis as well as facilitates laboratory investigations of the pathology of WNV.