The Williamson County and Cities Health District has found mosquitoes with West Nile virus in a mosquito trap in Leander's Devine Lake Park. This is the first positive trap in the country for 2025, but last month a person in southern Williamson County tested positive for the disease.

Public health officials in Solano County confirmed a positive West Nile Virus detection in mosquitoes collected from near the Birds Landing area in the Sacramento delta.

Health officials confirm two mosquito samples from Millcreek and Harborcreek Townships tested positive for West Nile virus in late July. These are the seventh and eighth positive samples in Erie County this year, but no human cases have been reported so far.