CHICAGO (CBS) — The common house mosquitos, which can carry West Nile Virus, are out in full force about three weeks early, because of a warm winter and the current hot and relatively dry conditions, which promote their development.

Linn Haramis, an entomologist with the Illinois Department of Public Health, told WBBM Newsradio’s John Cody that this weekend’s half inch of rain wasn’t enough to wash away the culex pipiens – or common house mosquito – which thrives on stagnant water for development.

He said there were 34 cases of West Nile Virus reported in Illinois last year, with three deaths.

LISTEN: WBBM Newsradio’s John Cody Reports

The state has reported 17 batches of mosquitoes that have tested positive for West Nile so far this year.

The best protection is using mosquito repellent during twilight and evening hours. Haramis also recommended emptying out any standing water, such as bird baths, clogged rain gutters, and fishing boats.

Mike Szyska, director of the Northwest Mosquito Abatement District, said he wouldn’t expect to see the house mosquitoes out until the very end of June or a week or so into July.

Unless there’s a series of rains heavy enough to wash mosquitoes out of catch basins and retention ponds, Szyska said there’s a good chance of many more swarms of house mosquitoes, which develop best in the hot dry weather Illinois has lately been experiencing.

Watch & Listen LIVE