Lack of rain and hot temperatures have created a perfect breeding environment for the mosquitoes that spread the West Nile virus.
The DuPage County Health Department is warning residents to take extra precautions as “we are entering a period of high risk for West Nile virus infection in humans,” according to the Health Department.
While mosquitoes known to breed in “floodwaters” have been eliminated due to the heat and high temperatures, those same conditions create a perfect breeding environment for the mosquitoes that carry West Nile virus, the Health Department said. The Culex mosquitoes are the main West Nile carriers.
“The hot summer temperatures, which are expected to continue, increase Culex mosquitoes, which in turn increases the proportion of birds infected with West Nile virus and the risk of human infection,” the DuPage County Health Department said in a news release issued Monday.
The Health Department finding the first mosquitoes carrying the virus, the finding came earlier than in the previous year. The warm weather earlier in the year was attributed as one reason for the early finding.
DuPage County is among 26 Illinois counties reporting positive mosquito tests for WNV so far this summer, with positive tests earlier than normal, according to the Health Department. It is reporting 89 positive mosquito tests this year in DuPage County compared with only one positive test at the same time last year. No human cases have been reported in DuPage County so far in 2012.
Only one test—from June 22—has come back positive in Woodridge, according to the county's West Nile virus tracker.
West Nile virus is transmitted to people from the bite of a mosquito, which gets the virus from biting an infected bird. Most people who get the virus have no symptoms. Some people become ill within three to 15 days of being bitten, according to the Health Department.
Woodridge residents who are interested in monitoring West Nile virus in the area may use an interactive map displaying the various incidents of positive and negative findings. The map of mosquito traps found throughout the county will be updated as mosquitoes test positive for West Nile virus, the Health Department said.
The DuPage County Health Department offers these tips to prevent West Nile Virus:
- Reduce exposure - avoid being outdoors when mosquitoes are most active, especially between dusk and dawn. 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 birdbaths, ponds, flowerpots, wading pools, old tires and any other receptacles.
- 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 produce mosquitoes.
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.