Health Department Cautions Residents About Increasing Risk
of West Nile Virus
The DuPage County Health Department cautions DuPage County
residents that current weather conditions indicate we are
entering a period of high risk for West Nile virus (WNV)
infection in humans.
State public health officials report that the dry conditions
have eliminated "floodwater mosquitoes," which are very
rarely infected with WNV. In contrast, the extreme heat and
dry weather are producing more Culex mosquitoes, the primary
carriers of WNV, which breed in street catch basins (storm
drains) and similar locations. Also, the high temperature
accelerates WNV multiplication in mosquitoes and mosquitoes
feeding on birds.
DuPage County is among 26 Illinois counties reporting
positive mosquito tests for WNV so far this summer, with
positive tests coming earlier than normal. The Health
Department reports 89 positive mosquito tests this year in
DuPage County compared to only one positive test at this
same time in 2011. No human cases have been reported in
DuPage County so far in 2012.
DuPage County residents who want to track WNV in their
communities may visit
http://maps.google.comdchdsurveillancemap. This map of
mosquito traps throughout the county will be updated as
mosquitoes test positive for WNV.
The Health Department is collecting freshly-dead birds (such
as crows or blue jays) for WNV testing. The birds must not
show any signs of decay or trauma. To report a dead bird,
call (630) 682-7400.
WNV 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 15 days after the bite of
an infected mosquito.
Only about two people in 10 who are bitten by an infected
mosquito will experience any illness. Illness from WNV is
usually mild and includes fever, headache and body aches,
but serious illness, such as encephalitis and meningitis,
and death are possible. Individuals over the age of 50 have
the highest risk of severe disease.
The best way to prevent WNV or any other mosquito-borne
illness is to reduce the number of mosquitoes around your
home and to take personal precautions to avoid mosquito
- REDUCE exposure - avoid being outdoors when
mosquitoes are most active, especially between dusk and
- 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 where
mosquitoes can breed, including water in bird baths,
ponds, flowerpots, wading pools, old tires and any other
- REPEL - when outdoors, wear shoes and socks, long
pants and a long-sleeved shirt, and apply insect
repellent that contains DEET, picaridin, oil of lemon
eucalyptus or IR 3535, according to label instructions.
Consult a physician before using repellents on infants.
- REPORT - 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