The Wisconsin Department of Health Services (DHS) announces the first West Nile virus (WNV) infections in Wisconsin this year in a healthy blood donor from Washington County, whose blood screened positive for WNV, and in a dead bird from Chippewa County that tested positive for the virus. The positive blood donor is not considered a human case because they never developed any symptoms of WNV, which is required to be a probable or confirmed case. The infections confirm that there are mosquitoes infected with WNV in the state that can transmit the virus to other people and animals. “The first activity of West Nile virus this year in Wisconsin is a reminder that we still need to take precautions to prevent mosquito bites even as summer winds down, as the risk of West Nile virus continues until the first frost. While West Nile virus and other viruses spread by mosquitoes pose a risk to all Wisconsinites, people who have weakened immune systems are at higher risk for significant illness,” said State Health Officer Paula Tran. WNV is spread to humans, birds, and other animals through the bite of an infected mosquito. Mosquitoes acquire WNV by feeding on infected birds. The virus is not spread directly from person to person, animal to animal, or animal to person
