Whole-Blood PCR Preferred for Timely Diagnosis of Neuroinvasive West Nile Virus Infections: Lessons From the 2021 Arizona Outbreak.

Taken together, these findings indicate that WNV PCR testing on WB may be the best initial test for timely diagnosis of WNV infection, irrespective of clinical manifestation; however, if negative in patients with suspected neuroinvasive disease, WNV PCR testing on CSF should be ordered.