(CBS) — The weather is perfect for mosquitoes. Unfortunately, it’s not the best for efforts to eradicate them.

The North Shore Mosquito Abatement District’s David Zazra says it’s not your imagination: the influx is worse than usual. It has been perfect for the floodwater mosquitoes, which bite at any hour, not just dawn and dusk.

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But the cool, wet weather is not conducive to the spraying Zazra’s employer and other mosquito abatement agencies use as the front-line defense. Zazra says, to be effective, conditions should be dry at night with temperatures in the 60s or warmer.

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The good news is that the floodwater mosquitoes don’t carry the West Nile virus. But if conditions dry, that will allow hatching of the disease-prone Culex mosquitoes to begin. Zazra said that in the past week, infected mosquitoes have been found in Winnetka, Skokie and Evanston. The mosquitoes can spread West Nile disease by biting infected birds and then humans.

Zazra says if you must be outside, try to cover up as much as possible to avoid being bitten, and to wear a DEET-based repellant. He also urges property owners to eliminate any pools of standing water, where the mosquitoes can breed.

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Zazra said the North Shore district, which serves 13 northern suburbs and portions of several more ranging from Evanston north to Glencoe and west to Niles, has been working since April to minimize the mosquito population. That has included treating more than 40,000 catch basins, one of the areas the Culex mosquitoes are known to favor for laying larvae.