The major flooding this spring may bring more mosquitoes in the summer months.

Swollen rivers will leave behind small ponds or pools as they recede back to normal levels. Those bodies of standing water offer ideal breeding grounds for Culex mosquitoes, the ones that predominantly carry the West Nile virus.

“It does not take much water for the females to lay their eggs,” said Howard Pue, state public health veterinarian for Missouri. “It might be a flooded ditch, or it might be a bottle cap with just a little water in it.”

The St. Clair County Health Department already found a mosquito that tested positive for West Nile this year.

Yet more favorable breeding conditions from the floodwaters don’t automatically translate to more cases of West Nile this year.

“It’s very difficult to predict how the mosquito season will flow each year. It’s heavily dependent on temperature and rainfall,” said Samantha Debosik, the vector control program manager at the Illinois Department of Public Health. “We’ll know more as the summer proceeds and we see how the temperatures line up.”

Public health officials recommend residents protect themselves by dumping any standing water around their yards and wearing insect repellant, especially at dawn and dusk when mosquitoes are most active.

Debosik also suggests wearing light-colored clothing with long sleeves.

“Mosquitoes are attracted to dark colors and dark shadows and movement indicating to them that an animal might be nearby,” she said.

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