CHICAGO (CBS) — The City is waging war against West Nile Virus. For the first time this summer, workers are spraying on the Northwest and Southwest Sides because mosquitoes there tested positive for the illness.

But some residents say they weren’t notified about the spraying, reports CBS 2’s Mike Parker.

The city of Chicago is taking no chances as it sprays its first doses of the pesticide Zenivex on Washington Heights and the Forest glen neighborhood on the NW side.

“Our information that we collect is part of our routine monitoring for West Nile Virus has indicated that there is an elevated risk of human infection of West Nile Virus in these two sections of the city,” said Dr. Cortlant Lohff of the Chicago Public Health Department.

So far this season infected mosquitoes have been found in Chicago, Glenview, Evanston, Skokie, Hillside and Kane County.

Chicago officials say residents of tonight’s targeted areas have been notified of the spraying but some South Siders say they’ve heard nothing

“No one has said anything. We didn’t know anything about it,” said Shawn Mitchell.

Mitchell says it bothers him because, “We got a lot of kids that play on the block.”

Janet Johnson plans on keeping her house sealed, saying, “The windows are closed anyway at this particular time because of the heat.”

In any case, the City says the pesticide is safe

When asked if the doses of Zenifex are harmful, Lohff said, “It is not.”

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