According to the Vanderburgh County Health Department (VCHD), one sample group of mosquitoes from a surveillance trap collected within the city of Evansville has tested positive for West Nile Virus. Officials say this is the first positive test of mosquitoes in Vanderburgh County this year.

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 risk for West Nile virus is high in 10 cities and towns in Massachusetts, including Boston, public health officials say.