West Nile Virus (WNV) is the most widespread and frequently reported mosquito-borne disease in the US, with a high risk of outbreaks. Accurate surveillance of WNV is complicated by many mild or asymptomatic infections, resulting in human cases being under-reported and disease distribution and transmission not being well understood. In this study, we investigated how wastewater surveillance can be used for monitoring WNV in Oklahoma. We analyzed samples collected from wastewater treatment facilities in 16 counties during July 1 to September 31, 2023, for the presence of WNV genetic material and compared the results to the distribution of notified WNV cases in humans and equines and WNV-positive mosquitoes. WNV was detected in wastewater from four locations in three counties. All positive wastewater samples were collected from counties with confirmed human cases and, in two counties, with positive mosquito pools. There was no geographical match between positive wastewater samples and equine cases. We did not detect WNV in wastewater samples from 13 counties, of which five did not report human cases and four had no reports of WNV-positive mosquitoes. Our study presents evidence that WNV genetic material can be detected in wastewater to which thousands of people have contributed. This highlights wastewater surveillance as a promising tool for understanding the distribution of emerging vector-borne diseases, particularly in areas where traditional surveillance approaches lack in representativeness and timeliness.
Copyright © 2025. Published by Elsevier B.V.