Press Release

May 27, 2005


SPRINGFIELD, Ill. – As temperatures increase, so does the activity of mosquitoes. Dr. Eric E. Whitaker, state public health director, today reminded Illinoisans to take precautions to protect themselves from mosquito bites, which can result in disease.

“Mosquito bites are not only irritating, they can lead to serious illness or even death if the mosquito transmits West Nile virus to a person,” Dr. Whitaker said. “People should protect themselves whenever they are outdoors.”

The best way to prevent West Nile disease or any other mosquito-borne illness is to reduce the number of mosquitoes around your home and to take personal precautions to avoid mosquito bites. Precautions include:

  • Avoid being outdoors when mosquitoes are most active, especially between dusk and dawn. Use prevention methods whenever mosquitoes are present.
  • When outdoors, wear shoes and socks, long pants and a long-sleeved shirt, and apply insect repellent that includes DEET, picaridin or oil of lemon eucalyptus according to label instructions. Consult a physician before using repellents on infants.
  • Make sure doors and windows have tight-fitting screens. Repair or replace screens that have tears or other openings. Try to keep doors and windows shut, especially at night.
  • Eliminate all sources of standing water that can support mosquito breeding, including water in bird baths, ponds, flowerpots, wading pools, old tires and any other receptacles. In communities where there are organized mosquito control programs, contact your municipal government to report areas of stagnant water in roadside ditches, flooded yards and similar locations that may produce mosquitoes.

So far this year, West Nile activity has been reported in DuPage and Woodford counties. Mosquito samples collected May 16 and May 19 in Naperville and May 23 in Wayne and a dead crow collected May 19 in El Paso have tested positive for the mosquito-borne virus.

West Nile virus is transmitted through the bite of a mosquito that has picked up the virus by feeding on an infected bird. Most people with the virus have no clinical symptoms of illness, but some may become ill three to 14 days after the bite of an infected mosquito.

Only about two persons out of 10 who are bitten by an infected mosquito will experience any illness. Illness from West Nile is usually mild and includes fever, headache and body aches, but serious illness, such as encephalitis and meningitis, and death are possible. Persons older than 50 years of age have the highest risk of severe disease.

Viruses are most likely to be spread during the warm weather months when mosquitoes are most active, usually beginning in May and lasting until the first hard freeze. Most human cases occur in late summer and fall.

In 2002, the state led the nation with 884 human cases, including 66 deaths, and West Nile activity was reported in 100 of 102 counties. Last year, there were 60 human cases and four deaths, and West Nile activity was reported in 62 counties. However, unusually cool weather in August 2004 suppressed a high level of mosquito activity that had occurred earlier in the summer. Consequently, hot summer weather this year could result in an increased number of cases in 2005.

Illinois’ surveillance for West Nile virus, which began May 1, includes laboratory tests on mosquitoes, dead crows and blue jays, and the testing of sick horses and humans with West Nile-like disease symptoms. Citizens who find sick or dying crows or blue jays should contact their local health department, which will determine if the bird is to be submitted for testing.

“ Knowledge of infected birds or mosquitoes in a neighborhood or community allows public health officials to alert citizens about the increased risk of mosquito-borne diseases and to direct mosquito control personnel to areas of high virus activity,” Dr. Whitaker said.

Additional information about West Nile virus can be found on the Department’s Web site at or people can call the West Nile Virus Hotline at 866-369-9710 Monday through Friday from 8 a.m. to 5 p.m.


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Illinois Department of Public Health
535 West Jefferson Street
Springfield, Illinois 62761
Phone 217-782-4977
Fax 217-782-3987
TTY 800-547-0466
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