Identification and characterization of novel lineage 1 Powassan virus strains in New York State.

Powassan virus (POWV, family ) is a reemerging tick-borne virus endemic in North America and Russia. In 1997, a POWV-like agent was isolated from in New England and determined to be genetically distinct from the original POWV isolate. This revealed the existence of two lineages: lineage 1, prototype Powassan virus (POWV-1) and lineage 2, deer tick virus (DTV).

Adaptive evolution of West Nile virus facilitated increased transmissibility and prevalence in New York State.

West Nile virus (WNV; Flavivirus, Flaviviridae) was introduced to New York State (NYS) in 1999 and rapidly expanded its range through the continental United States (US). Apart from the displacement of the introductory NY99 genotype with the WN02 genotype, there has been little evidence of adaptive evolution of WNV in the US. WNV NY10, characterized by shared amino acid substitutions R1331K and I2513M, emerged in 2010 coincident with increased WNV cases in humans and prevalence in mosquitoes.

and Cache Valley virus: a new threat for virus transmission in New York State.

We report surveillance results of Cache Valley virus (CVV; , ) from 2017 to 2020 in New York State (NYS). Infection rates were calculated using the maximum likelihood estimation (MLE) method by year, region, and mosquito species. The highest infection rates were identified among spp.