APPLETON, Wis. — Ongoing complaints about bedbugs in Outagamie County suggest the problem may not be going away any time soon.

The county doesn't require public reporting, so it's not exactly clear how severe the issue is. But health officials say the number of complaints has been growing, and pest-control experts say business has been growing more brisk in recent years, the Post-Crescent Media reported (http://post.cr/1aCX987 ).

Bedbugs are tiny insects that feast on human blood while their host sleeps. Appleton city health officer Kurt Eggebrecht says the city has received 19 bedbug complaints since 2008, with infestations reported in hotels, motels and even single-family homes.

County officials say the problem is especially prevalent in lodging facilities, which are now resigned to the idea that infestations will occur.

"Those establishments aren't left wondering if they'll ever arrive — they now assume they're coming in," said Natalie Vandeveld, the county's environmental health sanitarian.

Bedbugs are flat reddish-brown insects that bite at night and leave an itchy red welt. They can hitch a ride in travelers' luggage, especially when people pack bedding to take to summer homes or college dorms.

Jason Freels, the bedbug services manager with Batzner Pest Management, said Appleton's college campuses and the Fox Valley's hub of hotels is "a perfect storm" for the parasites.

"There's a known bedbug season from July to November," he said. "You have increased travel, increased moving, college kids in and out and a prevalence of used furniture."

Because the insects don't pose a serious health hazard or spread disease, there's no legal requirement to notify the public of infestations. Without a requirement, people seem reluctant to admit their homes or establishments have the bugs.

"For whatever reason you still see shame and embarrassment about the perception they did something wrong, but these can be introduced very easily," Freels said.

When the county is notified, it requires that a professional pest-control technician inspect the room and provide a report. Vandeveld said it makes sense to have an aggressive response.

"I think over the last couple of years, people in the Valley are recognizing the potential is here, so we're being more proactive, she said.

Eggebrecht warns that infestations aren't related to messiness, and even five-star resorts have been known to harbor the pests. He also noted that the bugs can't survive temperatures about 115 degrees, so he advises frequent travelers to put all their clothes into a hot dryer before they do anything else when they get home.

Vandeveld said hotels in the area are fighting back with more training and inspection, with housekeepers and maintenance staff recruited to do regular checks. The staffers will look behind headboards, under box springs and in mattress seams at every room change, she said.

Like many other pest-control professionals, Batzner uses a trained beagle to detect the bugs. When the parasites are found the company can attack them with chemical treatments, a thermal option with steam and whole-house heating, Freels said.

He warned that signs point to an impending surge of infestations that could spread from Milwaukee, Chicago or other cities.

"It's coming," Freels said. "Our call volume indicates it's spreading. You guys are going to have an increase over the next couple years. There's no doubt."