(CBS) — Mosquitos are back and the itching can drive you crazy.

So why are they so bad so early? CBS 2’s Roseanne Tellez talked with some experts.

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At first, you don’t see them, but they see you. And they’re out for blood.

Paul Geery, a biologist with the Des Plaines Valley Mosquito Abatement, monitors mosquitos in a 77-mile area in Central Cook Countys. He says recent warm weather and rain caused the population to take off.

“A lot of areas filled with water and a lot of eggs hatched and they are coming off the water these last four or five of days,” said Geery. “It is bad right now.”

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Just ask anyone who spends time outside.

Geery, who’s been treating water to kill mosquito breeding grounds, says for the best protection, use a repellent with DEET sprayed on your clothing, check window screens for gaps and holes and dump standing water.

“If you’re on your porch, set up a fan. They can’t land if there’s a fair amount of wind,” said Geery.

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The good news: the mosquitos collected so far this year are disease-free.