West Nile virus detected in mosquito samples in Illinois and Idaho

West Nile virus has been detected in mosquito samples in both Perry County, Illinois, and Bannock County, Idaho.

In Perry County, the first positive sample of the season was collected near the Tamaroa Sewage Treatment Plant in late August and confirmed on September 1. Health officials advise residents to reduce exposure by limiting outdoor activity at dusk and dawn, using insect repellent, and removing standing water.

In Bannock County, a mosquito pool in the Swan Lake area tested positive. While no human cases have been reported in the area, the Mosquito Abatement Office has increased larvicide and adulticide efforts, including drone and backpack spraying. Officials noted that recent dry and hot weather in Eastern Idaho has created stagnant water conditions that mosquitoes prefer, potentially increasing virus activity.