Does mild Illinois winter mean more biting bugs?

SPRINGFIELD — Whether we have extreme winter weather or mild, it won't make much difference come summertime to the bugs that sting, bite and harass us year after year.

“There are some exceptions, but for the most part, the insects we find in Illinois are adapted to conditions from Atlanta, Georgia to Churchill, Manitoba, Canada,” says Phil Nixon, extension entomologist with the University of Illinois. “Generally, most of our insects are not going to be bothered by particularly cold or warm weather to any extent.”

It has become a sort of conventional wisdom that the summer following a mild winter will produce a bonanza of insects because there wasn't enough frigid weather to cut into their survival rates.

But that's not necessarily true, Nixon says.

“They have a base temperature — about 50 degrees — to become active,” he says. “In a broad sense, 45 degrees is not much different than 5 below zero.

“They are sitting in a sort of suspended animation at those temperatures.”

In reality, it's spring weather conditions, not winter, that likely will determine how many insects survive.

“Cooler, damper springs mean fewer bugs,” Nixon says. “The major mortality factors are fungi that are specialized in attacking insects. And fungi do better in cooler weather.”

Warmer conditions, however, may lead to insects becoming active sooner.

“Some of our insects are overwintering as adults and they will become active under these conditions,” Nixon says. “The northern house mosquito will come out when it is 45 degrees, so people can get bit by a mosquito in the middle of winter.”

The lowly house mosquito can carry West Nile virus and other diseases, but the good news is the virus can't replicate itself in sufficient quantities until temperatures are substantially warmer.

“It needs to be in the 70s,” Nixon says. “Even if it is carrying West Nile virus, the virus hasn't reproduced in the mosquito enough to become effective.”

According to WebMD.com, most people infected with the West Nile virus never notice. Some people get a fever, headache, and body aches, or a rash on the trunk of the body. In a few cases, infected people can slip into a coma, develop paralysis or suffer brain damage. In rare cases, the virus is fatal.

Ticks also may become active earlier if the weather stays mild.

The American dog tick — or wood tick — can become active in the latter part of March. Ticks — really a type of large mite — aren't active below 50 degrees either.

Deer ticks — or black-legged ticks — are known to carry Lyme disease and are not active until it gets much warmer in June, Nixon says. People with Lyme disease usually develop a rash that looks like a target. Some people develop a fever, chills, headaches or fatigue. More serious cases lead to pain, weakness and inflamed joints. Patients are treated with antibiotics.

Hunters occasionally pick up a tick off deer during warm periods in late fall. But most people will come into contact with ticks when the weather is warm and shorts and short-sleeves come out.

“There is more exposed skin in the summer, and it's easier for them to latch on,” Nixon says.

Kathy Bacon, co-owner of Bacon Termite & Pest Control in Glenarm, says her company stays busy all year, servicing regular accounts during the winter months.

Many pests, such as spiders and roaches, don't pay much attention to the weather, although ants and termites respond when the warm spring rains fall.

“Spiders are pretty consistent from spring to fall,” Bacon says. “It doesn't matter what the weather is like. The only time we have a lot of ant problems is in the years when we have a lot of rain.”

Termites swarm in the spring and fall.

“It's usually between March and April, and usually when it gets warm and we start getting the spring rains, and then it is sunny and humid afterwards,” Bacon says.

Roaches are a tenacious problem all year long.

The weather is not a factor as much as their mode of travel. Bacon says they can easily arrive in a box shipped from a warehouse.

“When you order something online, you have the potential of bringing roaches into your home,” she says.

Boxes should be discarded right away and not kept around the house.

“That's a problem for restaurants or businesses that get consistent shipments,” Bacon says. “They tend to bring roaches in boxes.”

She emphasizes a house does not need to be dirty to have roaches.

“I tell callers not to apologize because even (houses in the nicest neighborhoods) get roaches.”