Publications & Sites 
Birds, mosquitoes test positive for West Nile in Lake County
Mosquito and West Nile Virus. | Sun-Times Media
TIPS ON
PREVENTING mosquito breeding
include:
Change the water in bird baths and plant urns at least once a week.
Discard old tires, buckets, drums or any water holding containers.
Poke holes in tires used as bumpers on docks.
Keep roof gutters and downspouts clear of debris and trash containers covered.
Empty plastic wading pools at least once a week and drain unused swimming pools.
Fill in tree rot holes and hollow stumps that hold water.
Store boats upside down or drain rainwater weekly.
It’s not often we think of mosquitoes as deadly, but Lake County Health Department officials are concerned they are seeing a spike in signs of the West Nile virus.
This year they have had two birds test positive for the virus, which killed one person in Lake County in 2005. Additionally, 32 mosquito batches have come back positive for the virus.
The birds were in Long Grove and Round Lake, and the batches came from central and southern Lake County communities of Libertyville, Mundelein, Vernon Hills, Deerfield, Highland Park, Deer Park, Hawthorn Woods and Buffalo Grove. But they also showed up in Zion and Waukegan.
“The last time we had a similar high number of positive mosquito batches at this time of year was in 2005, which resulted in 11 human cases and one death,” said Irene Pierce, the Health Department’s executive director. “This makes it all the more important to protect yourself against mosquito bites by following the three R’s — reduce your exposure to mosquitoes, repel them by wearing insect repellent and report areas where mosquitoes typically breed.”
These are not floodwater mosquitoes, but the Culex mosquitoes that carry West Nile virus. They tend to thrive in dry conditions and are sometimes called the house mosquito.
Mike Adam, senior biologist with the health department, said they now have a higher batch count than the same time in 2005, also a hot, dry summer. “And our 32 can be even more,” he said because some batches are tested in the field and others in the laboratory, which takes more time.
‘Stagnant water’
“The ones that are out there are the ones potentially carrying the disease,” he said. “They breed in stagnant water with lots of organic matter. It loves this kind of water. They like artificial sites like gutters and birdbaths,” he said.
The Lake County Health Department maintains a West Nile virus hotline for county residents to report areas of stagnant water, dead birds or to obtain more information on the signs and symptoms of West Nile encephalitis. The West Nile hotline number is (847) 377-8300.
While most people infected with WNV have no symptoms of illness, some may become ill, usually three to 15 days after the bite of an infected mosquito. In some individuals, particularly the elderly, the virus can cause muscle weakness, inflammation of the brain (encephalitis), stiff neck, stupor, disorientation, tremors, convulsions, paralysis, coma or death.
The Health Department recommends limiting outdoor activity at dusk whenever possible, and wear light-colored clothing that minimizes exposed skin and provides some protection from mosquito bites, along with applying insect repellents.
Lake County’s mosquito surveillance program begins in late spring and continues into the fall with a series of traps that are set around the county, including within Lake County forest preserves. At each site a pool, or batch, of mosquitoes is tested weekly for West Nile virus. Areas of stagnant water are also investigated throughout the season for the presence of mosquito larvae, specifically from the Culex mosquito. The locations of dead birds are monitored to assist in the assessment of potential West Nile virus activity.
