Not letting the bedbugs bite, classically just a line in an old nursery rhyme, has become an irritatingly real challenge for some.

According to the National Pest Control Management Association, the bedbug population has increased 500 percent in the past three years, and some of that has been seen in the Minneapolis area.

Stephen Kells, a professor of entomology, said there were many cases of bedbugs in the 1940s and 1950s, but by the 1960s, insecticides such as DDT killed them off.

“You go back into historic literature (and) you’ll see passages of people having a sport of how many bedbugs you can stick with a hatpin,” he said.

But bedbugs are returning, Kells said, because of increased travel and a lack of awareness.

Bedbugs started showing up en masse in 2000 and have increased rapidly, he said. They tend to show up in hotels.

“Hotels tend to act as collection points for bedbugs,” Kells said.

Grant Anderson, University coordinator of residential life, said there have been no reports of bedbugs at the University.

Kells said other campuses are experiencing infestations.

“University dorms are not off limits,” he said.

There often is a misconception that bedbugs are related to poverty, Kells said.

“It’s not the social-economic issue; it’s just the level of attention to detail,” he said.

People who tend to clean on a more regular basis have a higher chance of noticing the small bugs.

Bedbugs range from a quarter-inch to three-eighths of an inch or smaller, are very flat and move quickly.

Kells said people become suspicious of the bugs when they notice mysterious bites, often in a row, when they wake up. He said that while some people experience bumps from the bugs, others have no reaction.

The best way to get rid of bedbugs is to call a professional pest control company, he said.

Rick Standish, president of Professional Pest Control in Minneapolis, said that in the past he would only hear about bedbug cases every few years, but now he hears about them every few months.

Kells said that so far bedbugs have not been scientifically proved to be a carrier of diseases but that most of the work on bedbugs was done in the 1960s and 1970s.

“We’ve had literally a whole generation of entomologists come through who have never seen a bedbug,” he said.