First West Nile positive mosquitoes have been collected

June 15, 2018


The Illinois Department of Public Health confirmed it has collected mosquitoes that tested positive for West Nile virus in the state.

The North Shore Mosquito Abatement District staff collected the positive mosquitoes in Glenview and Morton Grove. No human cases of West Nile virus have been reported this year, so far.

West Nile virus is transmitted through a bite from a Culex pipiens mosquito, commonly known as a horse mosquito, that has picked up the virus by feeding off of an infected bird.

Monitoring for West Nile virus in Illinois includes laboratory tests for mosquito batches, dead crows, blue jays, robins and other perching birds, as well as testing sick horses and humans with West Nile virus-like symptoms.

People who observe a sick or dying crow, blue jay, robin or other perching bird should contact their local health department, which will determine if the bird will be picked up for testing.

West Nile virus symptoms can include fever, nausea, headaches and muscle aches. Although, symptoms can last from a few days to a few weeks, four out of five infected people won’t show any symptoms.

Those 60 and older with a weakened system are at a higher risk of severe illnesses caused by West Nile virus like meningitis or even death.

Last year, 63 counties in Illinois reported a West Nile virus positive batch, bird and/or human case.

In 2017, the IDPH reported 90 human cases (although underreported), including eight deaths. According to the Centers for Disease Control and Prevention, as of Jan. 9, 2018, a total of 47 states and the District of Columbia reported West Nile virus infections in people, birds, or mosquitoes in 2017.

Disease cases from mosquito, tick and flea bites have tripled in the U.S. during the 13 years from 2004 through 2016. Reported cases from mosquito and tick bites in Illinois have increased by more than half (58 percent) from 2005 to 2016. That also makes the risk for Lyme disease at an all-time high, especially during the warmer months.

“Ticks that transmit Lyme disease have been found in the county,” said Keith Wojnowski, the Director of Environmental Health for the Kankakee County Health Department. “To stay safe from ticks and mosquitoes, we tell the public the same thing that the state posts online.”

Wojnowski wants to remind the public to wear light clothing, stay directly on walking trails instead of going off into the trees or shrubs and to keep an eye out for stagnant water.

“The Culex mosquitoes love standing water that’s been there for weeks. Anything that can hold water, can breed mosquitoes,” he said.

As far as spraying or putting bug nets out, the park districts in the area aren’t required to do so, but the Kankakee County Health Department will be going out all summer and into the fall, to trap pools of mosquitoes to test them for West Nile virus.