The Sconi

The Wisconsin Department of Health Services (DHS) has reported the first West Nile virus (WNV) infections in Wisconsin for this year. A healthy blood donor from Washington County tested positive for WNV, and a dead bird from Chippewa County was also found to be infected with the virus. Despite testing positive, the blood donor is not considered a human case as they did not develop any symptoms, which are necessary to classify it as a probable or confirmed case.

State Health Officer Paula Tran emphasized the importance of continued precautions against mosquito bites: "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."

WNV is transmitted through mosquito bites after mosquitoes feed on infected birds. It does not spread directly between humans or animals. Most individuals infected with WNV do not exhibit symptoms; however, blood donations are screened to prevent transmission via transfusions.

Since 2001, DHS has monitored WNV spread, with an average of 18 cases reported annually among Wisconsin residents. Cases typically occur between June and October, peaking in August and September. Symptoms range from mild fever and headache to severe conditions such as paralysis and coma in less than 1% of cases.

To reduce exposure to mosquitoes and prevent illnesses like WNV, DHS advises minimizing contact with mosquitoes and eliminating breeding sites until temperatures drop below 28 degrees Fahrenheit for four consecutive hours.

For more information on mosquito-borne illnesses and protective measures, visit the DHS website.