The Knox County Health Department has detected West Nile Virus in mosquitoes in Knox County, and is taking steps to reduce the population of mosquitoes by spraying for them.

The Salt Lake County Health Department is warning residents to protect themselves against mosquito bites after confirming the first human case of the West Nile virus in 2025. The big picture: The adult was likely infected "with a more severe form of the disease" in late July,

West Nile Virus has shown up in nearly every area around Massachusetts this summer, with 181 mosquito samples have testing positive for the virus so far, according to the state Department of Public Health.