CHICAGO - First the floods came, and then the mosquitoes. An explosion of the pesky insects is pestering cleanup crews and just about anyone venturing outside in the waterlogged Midwest.
In some parts of Iowa there are 20 times the normal number, and in Chicago up to five times more than usual.
The good news is these are mostly flood water mosquitoes, not the kind that usually carry West Nile virus and other diseases. But they are very hungry and sometimes attack in swarms with a stinging bite.
Heavy rain followed by high temperatures creates ideal conditions for these bugs; their eggs hatch in the soil after heavy rains. Scientists call them nuisance mosquitoes.
"About 3 p.m. the bugs come out pretty bad. They're all over the place," Bill Driscoll, a flood cleanup worker in Palo, Iowa, said this week. "We've been burning through the repellent with the volunteers."
In Lisbon, Iowa, about 20 miles east of flood-ravaged Cedar Rapids, biker Larry Crystal said mosquitoes have made his rides miserable. "Every time I stop to rest at a rest area these buggers just find a way to bite me all over my neck area between my helmet and jacket," he wrote on a bikers' blog.
"They seem to be very aggressive. They're even coming into my helmet, finding any bits of skin," Crystal said. "They're just going at it."
Some mosquito surveillance traps in Iowa have as many as 20 times more mosquitoes than in recent years, said Lyric Bartholomay, an Iowa State University insect specialist.
For example, 3,674 mosquitoes were counted in Ames-area traps last week, compared with 182 for the same week last year, Bartholomay said yesterday. Trap quantities are just a snapshot of the number of mosquitoes flying around.
Mosquito numbers in northwestern suburbs peaked last week at about five times higher than normal for this time of year, said Mike Szyska of the Northwest Mosquito Abatement District.
There is no evidence of higher-than-normal numbers of Culex mosquitoes, commonly associated with West Nile virus. Several states have found evidence of West Nile, but only a few cases, which tend to start occurring later in July. But health authorities say that could change with drier weather, which Culex mosquitoes prefer.