West Nile Virus found in Chicago mosquitoes — what to know

The Chicago Department of Public Health has confirmed the first positive West Nile mosquito batch of the year within the city.

This discovery was made during routine sampling efforts, and thus far, no human cases have been reported.

The first group of mosquitoes testing positive for West Nile was identified on June 1st.


About one in five people infected by the virus can develop a fever and flu-like symptoms, according to health officials. For those who are over the age of 60, severe illness can occur.

Chicago residents are encouraged to take the following precautions against mosquitoes:

  • Use insect repellant that contains DEET, Picaridin, IR3535, or oil of lemon eucalyptus according to label instructions.
  • Eliminate standing water. Empty water from any outdoor containers, such as flowerpots, gutters, tires, toys, pet water dishes and birdbaths once weekly.
  • Keep grass and weeds short to eliminate hiding places for adult mosquitoes.
  • When outside between dusk and dawn, wear loose-fitting, light-colored clothing, long pants, long-sleeved shirts, socks and shoes.
  • Make sure that all screens, windows and doors are tight-fitting and free of holes. Repair or replace screens that have tears or other openings.
  • Check on neighbors regularly, especially those who are older, live alone or need additional assistance.

"As summer approaches, we want to ensure that all Chicago residents can remain safe and healthy," said Chicago Department of Public Health Commissioner Dr. Allison Arwady.

"The best way to protect yourself from mosquitoes and the diseases they carry is to prevent mosquitoes around your home and avoid mosquito bites."

Sun-Times Media Wire contributed to this report.