Once a pest of the past, bedbugs now infest every state in the U.S.. Cimex lectularius—small, flattened insects that feed solely on mammalian and avian blood—have been living with humans since ancient times. Abundant in the U.S. prior to World War II, bedbugs all but vanished during the 1940s and '50s thanks to improvements in hygiene and the use of pesticides. In the past 10 years, however, the pests have staged a comeback worldwide—an outbreak after the 2000 Summer Olympics in Sydney was a harbinger of things to come. This revival may be the worst yet, experts say, due to densely populated urban areas, global travel and increasing pesticide resistance—something to consider as the summer travel season gets underway.
"By every metric that we use, it's getting worse and worse," says Coby Schal, an entomologist at North Carolina State University in Raleigh. Health authorities and pest control operators are regularly flooded with calls, and the epidemic may not have yet peaked. And because bedbugs are indoor pests, there are no high or low seasons throughout the year, he adds, only continual bombardment. "It's just the beginning of the problem in the U.S.," Schal says.
Spreading rapidly with the bedbugs is a mass of misinformation about their biology and behavior. Straight from the experts, here are the facts behind some of the most notorious myths about the diminutive bloodsuckers.
Myth 1: Bedbugs can fly
Bedbugs lack wings, and therefore cannot fly. That is unless you put a blow dryer behind them, says Stephen Kells, a bedbug researcher at the University of Minnesota. Then they'll fly about 1.2 meters. On their own, bedbugs crawl about a meter a minute, he says.
Myth 2: Bedbugs reproduce quickly
Compared with other insects, bedbugs are slow to reproduce: Each adult female produces about one egg per day; a common housefly lays 500 eggs over three to four days. Each bedbug egg takes 10 days to hatch and another five to six weeks for the offspring to develop into an adult.
Myth 3: Bedbugs can typically live a year without a meal
Scientists debate this point, but evidence suggests that at normal room temperature, about 23 degrees Celsius, bedbugs can only survive two to three months without a blood meal. But because they are cold-blooded, their metabolism will slow down in chillier climates, and the insects may live up to a year without feeding.
Myth 4: Bedbugs bite only at night
Although bedbugs are generally nocturnal, they're like humans—if they're hungry, they'll get up and get something to eat. "If you go away to visit a friend for a week and you come back and sit down on the couch, even though it's daytime the bedbugs will come looking for you," Schal says. Keeping a light on, then, unfortunately does not keep these tiny vampires away.
Myth 5: Bedbugs live exclusively in mattresses
"'Bedbug' is such a misnomer," Kells says. "They should also be called pet bugs and suitcase bugs and train bugs and movie theater bugs." Bedbugs spread away from beds into living areas and can be seen on any surface, he says, including chairs, railings and ceilings.
Myth 6: Bedbugs prefer unsanitary, urban conditions
"Bedbugs are terribly nondiscriminatory," Schal says. Bedbugs can be found anywhere from ritzy high-rises to homeless shelters. The prevalence of the bugs in low-income housing is therefore not a result of the insect's preference, but of dense populations and the lack of money to pay for proper elimination strategies. "Any location is vulnerable," Kells says. "But some people are going to have a harder time getting control of them because it is such an expensive treatment."
Myth 7: Bedbugs travel on our bodies
Bedbugs do not like heat, Kells says. They therefore do not stick in hair or on skin, like lice or ticks, and prefer not to remain in our clothes close to our bodily heat. Bedbugs are more likely to travel on backpacks, luggage, shoes and other items farther removed from our bodies.
Myth 8: Bedbugs transmit disease
Bedbug bites can lead to anxiety, sleeplessness and even secondary infections, but there have been no reported cases of bedbugs transmitting disease to humans. They do, however, harbor human pathogens: At least 27 viruses, bacteria, protozoa and more have been found in bedbugs, although these microbes do not reproduce or multiply within the insects. Canadian researchers announced (pdf) in the June issue of Emerging Infectious Diseases that bedbugs isolated from three individuals in a Vancouver hospital carried methicillin-resistant Staphylococcus aureus, aka MRSA. Still, there have been no reported cases that the bugs actually transmit human disease.
Myth 9: We should bring back DDT
When the controversial pesticide DDT was banned in 1972, most bed bugs were already resistant to it, Schal says, and today's populations are even more widely resistant thanks to the use of a new class of pesticides. Pyrethroids, the main class of pesticides used against bedbugs today, targets sodium channels in bedbug cells, just like DDT. Consequently, as bedbugs develop resistance to pyrethroids, they also become cross-resistant to DDT.
Myth 10: You can spray bedbugs away
Thanks to pesticide resistance, those cans of spray at your local hardware store simply will not do, Schal says, adding: "Relying strictly on chemicals is generally not a good solution." The most effective solutions are fumigation and heat treatments, but these can cost a cool $2,000 to $3,000 apiece for a single-family home. Scientists are diligently pursuing other strategies, including freezing and bait similar to that used for cockroaches. In the October 2010 issue of the Journal of Economic Entomology Schal and colleagues at the U.S. Department of Agriculture published a technique that employs inexpensive infrared and vibration sensors to track bedbug movement, which could be applied to the development of automated traps that detect the pests.