Uptick in West Nile-infected mosquitoes comes weeks early for Chicago area

The Chicago area has seen an uptick in the number of mosquitoes infected with the West Nile virus in the last week, which is much earlier in the summer compared to previous years.

"We're not only seeing a lot of Culex mosquitoes, which are the carriers of West Nile virus, but we're seeing lots of West Nile virus in them," he said.

Earlier this month, an Aurora woman and a Wheaton woman contracted West Nile virus.

Officials with mosquito abatement districts and health departments are now on alert, warning residents and eliminating standing water. They are urging people to wear repellant and avoid getting bit by mosquitoes.

"Our concern, of course, is trying to prevent more cases as we move through the summer," said Kevin Dixon, the DuPage County Health Department's director of environmental health services.

Spikes in mosquitoes with the West Nile virus have been reported in DuPage and Will counties, as well as by the North Shore Mosquito Abatement District (NSMAD).

"Our levels of West Nile are above average," said NSMAD Executive Director Mark Clifton. "We're approaching those thresholds where we would see human infections."

Clifton said he doesn't normally see these levels of West Nile-infected mosquitoes until mid- to late August. West Nile virus thrives in dry, hot weather, he said.

"It's probably not going to get better soon. The risk is probably going to increase most likely," he said.

The DuPage County Fair is working to keep visitors safe.

The fair has reworked the drainage system, contracted an abatement company and have turned a former refuse area into a stable natural landscape, said fair manager Jim McGuire.

"Keeping it fresh, keeping it nice," McGuire said.

Mosquito experts say there's no way to tell if we're at a peak for West Nile yet, because it depends on the weather. Cold and damp weather will likely reduce those chances to get infected. Chances of getting infected go up during hot weather and then decline typically after the first frost of the year.