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As if you needed something else to worry about, a scourge from the last century is rearing its ugly head. Or, more to the point, its sucker.
Bed bugs, that pest from the old bedtime rhyme (Sleep tight. Don't let the bed bugs bite.), are making a comeback. More of a nuisance than a health hazard, they are showing up to suck blood from guests in hotels, college dorms, and hospitals.
One thing is certain: You don't want them. WebMD talked to entomologist Richard J. Pollack, PhD, research associate with the Harvard School of Public Health in Boston, and Cindy Mannes, vice president of public affairs for the National Pest Management Association (NPMA) in Fairfax, Va., about what you can do to keep them from becoming a public health issue, how to avoid bringing bed bugs home, and what to do if you suspect you have them.
Bed Bugs and Public Health
"The bites can cause distress, a few people have allergic reactions, and scratching can lead to secondary infection, but bed bugs are not known to transmit infectious diseases to humans," says Pollack. "You don't have to worry about who the bed bug fed on earlier. You're not going to get hepatitis B or C, malaria, or HIV."
He says the critters do become a public health burden, however, if people go ballistic trying to get rid of them. "Many people, whether they think they have bed bugs or truly do, will attempt to apply insecticides in their homes and on their beds. They don't know what they're doing, they don't read the labels, and they can overexpose themselves to something, which, if used properly, would pose minimal risk."
Pollack says some people call in an expert, find out what insecticide will be used, and decide they can buy the insecticide on the Internet and do it themselves. "Few people know what they're applying, how to mix it, how to apply it, and what the risks are if they misuse it. I actively dissuade folks from doing things on the cheap. Hire a licensed professional."
If you're a renter and suspect an infestation, don't let your landlord take matters into his own hands. Massachusetts law prohibits landlords from applying pesticides to common areas and to units other than those they occupy. They must hire a licensed pest control operator. "There are good reasons for this," says Pollack. "Most landlords don't know what they're doing."
A caller to a recent public radio show on which Pollack was interviewed asked about using kerosene to eliminate bed bugs. Indeed, that was an old folk remedy. Some people used to place their bedposts in cans filled with kerosene. We can only hope they didn't smoke in bed.
What about the ionic, ultrasonic, or electromagnetic products advertised on TV or the web? "These things are amazingly effective at reducing the thickness of your wallet," he says.
In addition, people spread the problem if they throw out an infested mattress that hasn't been properly treated. "Someone comes along and sees it on the curb, decides it looks better than what they have, and picks it up," he says.
Know the Enemy
Adult bed bugs are wingless insects about one-quarter of an inch long and oval in shape. Their color is nearly white after molting, then ranges from tan to burnt orange. After a blood meal, they'll appear dark red or black.
Their flat bodies enable them to hide in dark, cozy cracks and crevices in beds, baseboards, sofas, and drawers, and even behind wallpaper and electrical switchplates. That's where they nest during the day, typically not far from where they'll find their host -- that's you -- at night.
Amazingly, these sneaky little bloodsuckers dine on you without causing you to lose sleep. The next morning, you'll discover lesions that resemble the bite of a mosquito or some other insect.
Bed Bug or Imposter?
If bites occur while people are sleeping, suspect a bed bug infestation but don't leap to conclusions.
Forget everything you've heard about being able to tell the biter was a bed bug by looking at a bite. "I feed all kinds of bloodsuckers on my body, and in the vast majority of cases you can't look at a mark and tell what made it," says Pollack. "I recently gave a talk to physicians and quizzed them on pictures of bites, and their batting average was zero. The bites resemble those of other blood-feeding insects, such as mosquitoes, fleas, biting gnats, or mites."
He recommends the following steps for identifying the culprit:
1. Search the bedroom. Look in folds and creases in mattresses and box springs, pleats of curtains, behind loose wallpaper, in spaces of wicker furniture, behind cove molding, and in corners of drawers. You may notice dark-brown or reddish fecal spots on bed linens, mattresses, or walls near the bed.
2. When you find an insect, compare it with a good reference image, such as the one on the Harvard School of Public Health web site, or place it in a plastic bag or pill bottle, and take it to an entomologist at an extension agency for identification.
Make a positive identification before going to the expense of hiring a licensed pest control operator. "In many markets, it costs several hundred dollars to treat a one-room apartment, and don't be shocked at spending a grand or more to treat a single-family house," says Pollack. The cost is in expertise and labor. "If they're doing a quick look-see and they're out the door, you're not getting what you paid for."
What to Expect From a Pest Control Professional
Mannes says that the NPMA's member pest control companies who used to receive one or two bed bug calls a year now report one or two each week. "That's 50 times more calls."
When you call in a professional, they'll spend a lot of time looking for hiding places with a flashlight. "Bed bugs are very elusive," she says. "The pest control professional will look under box springs and in mesh that covers the box springs, go through drawers, and remove sofa cushions.
"The bed is ground zero, but it's not the only place they live," says Mannes. "What takes longest is finding out where they live. They can hide in picture frames, headboards, upholstered furniture, and baseboards.
Treatment depends on how serious the infestation is. "It could be anything from industrial vacuuming to using heat treatments to applying products in various places."
The person you hire will also advise you on what you can do to manage the problem, such as eliminating clutter or encasing mattresses in plastic covers.
She adds that bed bugs are like termites, not something the homeowner can find or treat on his or her own. You can also expect that the professional will have to come back to inspect and/or do follow-up treatment. "It's not a once-and-you're-done kind of thing," she says.
To confound this perplexing problem, Pollack says there's a well-known phenomenon in which lesions re-appear long after someone has been bitten. "They look and feel just like bed bug bites."
Don't Bring Stowaways Home
Pollack says most hotels and hotel rooms aren't infested. But regardless of the number of stars a hotel boasts, he says he takes certain precautions when he enters a hotel room. First, he sets his suitcase off the floor on the luggage holder provided, leaving the suitcase zipped unless he's taking something out or putting it in. Then he inspects the bed. "I pull back the covers, the sheets, and mattress pad and look for telltale signs -- the dark spots left by bed bug feces. If I found something, I'd go ask for another room."
Don't apply pesticides to hotel mattresses. "If you apply a product other than according to the label's instructions, you could be putting yourself and other people at minor or fairly extreme risk," says Pollack. "If you apply it to a hotel mattress, chances are no one will know, but there are specific laws about who can apply pesticides and where."
If you suspect that critters have hitchhiked home, launder clothes on high heat or dry clean them, and inspect suitcases before taking them inside. Use a stiff brush to remove eggs, and vacuum. Leaving luggage for several hours in a closed vehicle in full summer sun may destroy bed bugs and their eggs.
What About the Bedtime Rhyme?
Bed bugs have been bugging humans for years. They're mentioned in ancient Greek and Roman writings and the Talmud. Most of us grew up hearing, "Good night. Sleep tight. Don't let the bed bugs bite." Where did it come from?
No one is sure. One popular theory is that "sleep tight" goes back to the days when a mattress was supported by ropes that could slacken and make the bed uncomfortable, but according to the Oxford English Dictionary, it means to sleep "soundly, properly, well, or effectively." Bed bugs probably migrated to North America in the seventeenth century and thrived until the mid-20th century when they were eradicated with pesticides. But other bloodsuckers, like fleas, could also attack the hapless sleeper. You might presume that to "sleep well" meant getting through the night without providing a banquet for bloodsucking insects.
Published August 9, 2006.
SOURCES: Cindy Mannes, vice president, public affairs, National Pest Management Association, Fairfax, Va. Richard J. Pollack, PhD, research associate, Harvard School of Public Health, Boston. Harvard School of Public Health web site.