Wake up with itchy spots? A look at what bites at night

Q: My wife and I are waking up with spider bites on our legs. My wife, who gets most of the bites, wants to spray for spiders around the house. Is this a good idea?

A: No, because it's not spiders that are biting you.

Spiders are shy and seldom bite unless provoked, according to University of Minnesota extension entomologist Jeff Hahn. And if they do, few spiders are capable of breaking the skin.

What's more likely to be biting you are bedbugs. Bedbugs are very small, flat, round, brown insects. They hide during the day in mattress or box spring seams, or in crevices in the furniture. At night, when the house settles down, they become active and feed on the blood of those they find in bed with them. Bedbug bites normally do not hurt at the time, but often swell and become itchy later, Hahn says.

So, you might ask, how did we, a clean, normal American couple, end up in bed with bugs?

Lots of ways.

• Have you traveled recently? Once rare and associated with seedy places, bedbugs are showing up in hotel rooms regardless of price. Although the pests were nearly eradicated in the United States in the 1950s, they're now flourishing, some say, because of growing international travel and insecticide bans. Bedbugs are expert hitchhikers that stow away on clothing and luggage.

• Have you purchased or been given any used furniture? It's not common, but it happens, that used items harbor bedbugs.

• Have you just moved into this place? Once infested, bedbugs can be hard to eradicate from a home, because they seldom stay in bed. They spread to baseboards, upholstered furniture, curtains, etc. Just because the previous owners moved, it doesn't mean the bedbugs went with them.

• Have you had any guests recently? Visitors can innocently deliver bedbugs to your home they picked up on their travels.

I may be wrong and it's not bedbugs, after all, but fleas. Hahn describes fleas as dark-colored and the size of a pinhead. They are able to jump. You rarely feel a flea bite at first. But afterward, a red, itchy spot often appears at the site of the bite. Flea bites often occur in clusters on legs and ankles. You don't need pets in your home to have a flea problem.

The first step is a correct diagnosis.

• Consult your doctor to make sure it's not allergies, disease or contaminants that are causing your "bites."

• Examine the room for pests. Check mattress seams, look under the corners of the box spring and use a small mirror, if necessary, to look at the headboard, etc. After a feeding, the normally tiny woodtick-like insect becomes purplish-red and more cigar-shaped. Fecal deposits (composed of digested blood) look like a scattering of pepper.

Fleas will appear as specks that jump.

• Have an expert identify any suspicious insects or spiders you find.

"It is also a good idea to put out sticky traps like roach traps to help capture insects that are present but difficult to detect," Hahn said. "You may also consider hiring a professional pest control service to help you determine if any pests are there."

• Don't attempt control (especially spraying an insecticide) until you have verified that an insect problem exists.

Fixit by Karen Youso is an occasional feature. Send questions to fixit@startribune.com. Sorry, no personal replies.