Mosquitoes test positive for West Nile virus in Lake County

WAUKEGAN – A batch of mosquitoes sampled June 23 in Highland Park has tested positive for West Nile virus, according to the Lake County Health Department.

The mosquito pool is the first confirmed indicator of West Nile virus presence in Lake County this year.

“As we approach the summer season, our time outdoors increases and so does our exposure to mosquitoes,” said Mark Pfister, executive director of the Lake County Health Department and Community Health Center. “Please remember to ‘Fight the Bite’ and protect yourself and your family from mosquitoes that may carry West Nile virus.”

Practice the “4 Ds of Defense” to protect yourself and your family from mosquitoes:

• Drain: Drain standing water from items around your home, yard and business.

• Defend: When outdoors, use an insect repellent containing DEET, picaridin, oil of lemon eucalyptus, 2-undecanone, or IR3535 and reapply according to label directions.

• Dawn and dusk: Protect yourself all day and night, and wear repellent outdoors during these prime times for mosquito activity.

• Dress: Wear long sleeves, pants and closed-toe shoes when outdoors to cover your skin.

Culex pipiens mosquitoes, which are the primary carriers of West Nile virus, are most abundant when the weather is hot. Residents can help prevent these mosquitoes from breeding by eliminating areas of stagnant water from their properties. Items such as buckets, gutters and plant containers, kiddie pools and any other items holding water around homes and businesses can become breeding sites.

The Lake County Health Department’s Mosquito Surveillance Program coordinates mosquito trapping results throughout Lake County. Mosquitoes are tested weekly for West Nile virus. The program also monitors reports of dead birds (an early sign of the presence of the virus) and investigates areas of stagnant water for the presence of mosquito larvae, specifically from the Culex mosquito, which is the primary carrier of West Nile in Illinois.

“While the hot, dry weather results in fewer mosquitoes overall, the Culex mosquitoes that cause West Nile virus are still present,” said Alana Bartolai, ecological services program coordinator at the Lake County Health Department. “The years with the most cases of West Nile virus have often been during hot, dry summers.”

In 2021, 218 pools or batches of mosquitoes tested positive for West Nile virus. Since 2002, there have been 78 confirmed human cases of West Nile virus in Lake County, as well as four confirmed deaths.

Most people infected with West Nile virus have no symptoms of illness. However, some may become ill usually three to 15 days after the bite of an infected mosquito. Common symptoms include fever, nausea, headache and muscle ache. In some individuals, severe illness including meningitis or encephalitis, or even death, can occur. People older than 50 and individuals with weakened immune systems are at higher risk for severe illness from West Nile virus.

Find more prevention tips and information on West Nile virus at FightTheBiteNow.com. Residents can call the health department’s West Nile hotline to report areas of stagnant water, locations of dead birds and obtain more information on the signs and symptoms of West Nile virus. The West Nile hotline number is 847-377-8300.