The Northwest Mosquito Abatement District, http://www.nwmadil.com/ and the North Shore Mosquito Abatement District http://www.nsmad.com/ do spraying in Niles.
The districts work to control the mosquito larvae before they hatch. They also have traps set up and when the adult population reaches a certain level they will go out and spray. Weather conditions do impact the schedule, such as rain and wind.
As they are a separate taxing district, the district is separate from the Village and the Village does not schedule when the districts spray. Both districts provide information on their website when they will be spraying, and you can sign up to receive notifications from the North Shore District via text or email.