Mosquitoes test positive for West Nile virus

© 2018-Mendota Reporter

Infected mosquitoes found in LaSalle

OTTAWA – The LaSalle County Health Department received confirmation that mosquitoes from LaSalle tested positive for West Nile virus. The mosquitoes were collected and tested on July 24.

Environmental Health staff was able to conduct the confirmatory test on the mosquitoes at the Health Department. This is the first documented West Nile virus activity in LaSalle County this year.  

According to Chris Pozzi, Director of Environmental Health, “This is the time of year we expect to see West Nile virus activity increase. It is imperative that people be conscientious about self-protection whenever they are outside during the evening hours. In hot, dry weather, mosquitoes that carry West Nile virus breed in stagnant water and multiply rapidly. The best way to protect yourself against illness is to wear insect repellent and to get rid of any stagnant water around your home to reduce the number of mosquitoes.”

West Nile virus is transmitted through the bite of a Culex pipiens mosquito, commonly called a house mosquito, which has picked up the virus by feeding on an infected bird. Common West Nile virus symptoms include fever, nausea, headache and muscle aches. Symptoms may last from a few days to a few weeks. Four out of five people infected with West Nile virus will not show any symptoms. However, in rare cases, severe illness including meningitis or encephalitis, or even death, can occur. People older than 50 and immunocompromised individuals are at higher risk for severe illness from West Nile virus.

Precautions include practicing the three “R’s” – reduce, repel and report.

REDUCE – 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. Eliminate, or refresh each week, all sources of standing water where mosquitoes can breed, including water in bird baths, ponds, flowerpots, pet bowls, clogged rain gutters, wading pools, old tires, and any other containers.

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 – report locations where you see water sitting stagnant for more than a week such as roadside ditches, flooded yards, and similar locations that may produce mosquitoes. The local health department or city government may be able to add larvicide to the water, which will kill any mosquito eggs.

A complete listing of West Nile virus statistics for LaSalle County is available on the Health Department’s web site at A state-wide listing is available at the Illinois Department of Public Health’s web site at


Video News
More In Home