The Knox County Health Department reported reported 2025’s first two cases of La Crosse, a virus spread by mosquitos last month. So far in 2025, the CDC is reporting 10 cases across the U.S. Nearly a third of those are in Tennessee, which also has the most cases of all the states listed.

Routine West Nile virus testing by the Windsor-Essex County Health Unit has "identified positive mosquito pools in our community."

Mosquitoes carrying West Nile virus have officially been detected across all five boroughs, according to the New York City Health Department. As of Friday, mosquitoes carrying West Nile virus have been found in 89 ZIP codes.

The Monroe County Health Department said the sample was collected by the department as part of its Mosquito Surveillance Program.

Crews will spray for mosquito control this week in neighborhoods around Central Avenue in North Knoxville, the Knox County Health Department announced. West Nile virus - which is transmitted via mosquitos and can cause fever,