Bedbug invasion?

The hand-wringing in Paris last fall over tiny invaders — bedbugs — was palpable continents away. Viral social media posts drove residents of the French capital into high alert, searching for bedbugs hiding in hotel bedding and scooting across theater seats. Within days, reports surfaced that the critters were also spotted on the London Underground, hundreds of miles away.

While the evidence was mostly anecdotal, a Harvard expert says bedbugs have resurged here and abroad over the past few decades due to several factors — and it's always the right time to stay alert to ways you may encounter them and unwittingly bring them home.

"Yes, bedbugs are becoming a bigger problem, but there's a certain amount of media hype driving these reports," says Richard Pollack, a senior environmental public health officer in Harvard University's Department of Environmental Public Health and Safety. "I don't think it helps to be fearful. Even if you do find bedbugs in your home, you can put your energy toward strategies to take revenge."

Hidden figures

No larger than about a quarter-inch, the flat, flightless parasites known as Cimex lectularius hide in dark, enclosed spaces and feed solely on the blood of people and animals. Nearly eradicated more than 50 years ago, bedbugs' resurgence likely results from their growing resistance to commonly used pesticides, Pollack says.

"We've entered an arms race between nature and humankind," he says, "and the bugs are staying in lockstep, developing ways around whatever we throw at them."

Bedbugs tend to go unnoticed because they're mainly active when people are asleep, and the pests' saliva contains an anesthetic. After about five minutes or so of feeding, they retreat into the crevices near where their host is sleeping.

Bedbugs don't transmit disease-causing germs, but they're not necessarily harmless, either. Many people don't react to bedbug bites, but others develop an allergic response to their saliva. Itchy, red welts resembling mosquito bites may erupt. When a person scratches them, bacteria from beneath her nails can infect the tiny wounds.

The good news? Most bites don't require treatment, and the itching will resolve in about a week. Scratching worsens and extends how long the itching lasts. Some people use cold compresses, antihistamines, or topical steroid creams to quash symptoms. A small number of people may need antibiotics if the bites become infected.

"Not everyone will react to a bedbug bite," Pollack says. "Those who do react may begin to suffer itching at the bite sites minutes, hours, or even days after the encounter."

Keeping them away

There is much you can do to prevent bedbugs from finding their way into your home and onto your bedsheets. Pollack suggests the following strategies.

When you travel: Place your luggage on a table or luggage rack instead of on the bed. Before settling in, pull back bed linens and sheet corners, exposing mattress edges and seams. Look for dots signifying bedbug feces. Let management know immediately if you find evidence of the pests.

When you return home: Unpack directly into the washing machine (set on hot) or run your clothes in a hot dryer for about 20 minutes. You can also press them under a hot iron. Inspect and vacuum your suitcase, inside and out. "Everything gets cleaned and dried before it comes back into my living spaces," Pollack says.

When you visit others: Hang your coat and purse on a hook or in a closet away from the bedroom. Don't pile your coat along with those of others on a bed or other surface.

When you purchase used furniture: Inspect items carefully before bringing them home. Be extra cautious about furniture left out on sidewalks.

Confirming the problem

Getting rid of bedbugs can be expensive, depending on how much they've infiltrated a dwelling. But before you shell out hundreds or thousands of dollars, make sure you actually have them — and not the ubiquitous carpet beetles that can mimic them. "Some people are sensitive to the tiny hairs on beetle larvae and end up with a rash, and often those rashes are mistaken to be caused by bedbugs," Pollack says.

Along those lines, it's important to hire a licensed, reputable pest control firm if you suspect bedbugs have invaded your home. Don't spray your belongings or use any unprescribed medications in an attempt to eradicate them yourself.

"Before anyone considers treating for bedbugs, it's critical to confirm you know what's causing the problem and who the villain is," Pollack says. "Interview the pest management firm and find out what they know, what they're going to do, how much they'll charge, what insurance they have, and what their warranty provides."

Image: © Joel Carillet/Getty Images; illustration © dblight/Getty Images