First 2025 human case of West Nile virus reported in Lake County

The first human case of West Nile virus this season has been reported in Lake County.

A county resident in their 70s became ill in early July, according to the Lake County Health Department, although the sex, location or condition of the person was not provided. Last year, six human cases were reported in Lake County.

The first batch of mosquitoes testing positive for the virus in Lake County were sampled June 24 at a Southlake Mosquito Abatement District trap in Highland Park.

So far in 2025, nine of 214 batches tested throughout the county have tested positive for West Nile, which typically peaks in late summer from July through September.

According to health officials, most people infected with the virus have no symptoms although they can occur usually three to 15 days after a bite from an infected mosquito.

Symptoms include fever, nausea, headache and muscle aches. In rare cases, the virus can affect the brain or spinal cord leading to stiff neck, confusion, sudden weakness or numbness on one side of the body, trouble walking and even death, health officials say.

Those older than 60 or with weakened immune systems and/or multiple medical conditions are at higher risk from severe illness from West Nile virus, according to the health department.

Health officials recommend draining standing water on your property; using insect repellent with DEET, picaridin, oil of lemon eucalyptus, 2-undecanone, or IR3535; being aware that dawn to dusk is prime mosquito time; and, wearing long sleeves, pants and closed-toe shoes outdoors to cover your skin.

Visit FightTheBiteNow.com or to report areas of stagnant water, location of dead birds or to learn more about the signs and symptoms of West Nile virus call the hotline at (847) 377-8300.