By URSULA REUTIN
KIRO Radio

These hot summer nights aren't the only reason many people are "sleepless in Seattle" these days. Bed bugs are becoming a huge problem.

"I consider it sort of the epidemic of the 21st century," said David Hickock, the bed bug expert for the Seattle-King County Health Department. "There are so many people who are unaware of what they are, but the numbers of bed bug infestations are growing exponentially. We're getting several calls about them every day," he said.

Local exterminators report their business has shot up by 70 percent in the last two years. Last week, a section of an Everett homeless shelter was shut down temporarily because of a bed bug outbreak. But Hickock is quick to point out that this is not a problem that only affects low income populations. He says you can find the nasty critters in luxury hotels, hospitals, movie theaters, and buses.

"Their only food is human blood," Hickock said. "So once they're full, they go back to their hiding places, like mattresses and headboards, and then wait for their next meal."

So, what does a bed bug look like? When they're adults, they look like an apple seed. They're definitely visible. The six-legged pests are not so easy to spot when they're babies because they're only the size of a grain of salt. However, if you don't see the actual bed bugs, you might notice other tell-tale signs, including black fecal stains and the shells they leave after molting. There are also the big, red bumps they leave on your skin, often in clusters.

But the only way you can tell for sure if you have a bed bug problem is to catch one alive and bring it to a pest control expert. Don't just run to your neighborhood hardware store and get a bug bomb.

"That is the worst thing you can do," said Hickock. "That only spreads them everywhere and will make it even harder to get rid of them."

It's typical for an extermination job to cost anywhere from $300 to $1,000 because it takes several attempts, and even then, there's no guarantee they won't come back. Bed bugs can live a year without eating and they reproduce like crazy.

"You can start off with one and six months later you'll have 30,000," said Hickock.

While bed bugs are definitely a nuisance and cause of a lot of stress, they are not a public health threat. Hickock says there's no evidence that they carry and spread diseases.