10 Myths About Bedbugs

What You Think You Know About Bedbugs

Bed Bug
This adult bed bug, Cimex lectularius, is feeding on human blood. Matt Meadows/Photolibrary/Getty Images

There are a lot of misconceptions about the humble bedbug. Bedbugs (or cimicids) belong to a highly specialized family of insects that feed off of the blood of humans, bats, and birds. The best-known members are the temperate-climate human parasite Cimex lectularius (which means "bedbug" in Latin) and Cimex hemipterus, a tropical version. Bedbugs are the most widely recognized insect in the world, known to have fed on humans whenever and wherever they sleep for more than 4,000 years—and probably considerably longer.

Bedbugs are obligatory hematophagous ectoparasites, which means that they feed only on the blood of vertebrates. There are varieties of cimicids that feed on birds and bats, but our particular troublemaker feeds on humans.

Here are some of the common myths about bedbugs.

If You Wake With Insect Bites, You Have Bedbugs

Bedbugs tend to bite on locations that are exposed during sleep, on the arms, legs, and back as well as the face and eyes, particularly sites that lack hair and have a thin epidermis and plentiful blood.

However, bedbugs are not the only nocturnal feeder on humans. Quite a few other arthropods could be the cause of your bite marks, including fleas, mites, spiders, or even bat bugs. Also, many medical conditions cause rashes that look similar to bug bites. If the marks persist but you don't find signs of an infestation, consider a trip to your doctor.

Are you the only one in your household waking up with bites? People react to bedbug bites differently, just as they do with mosquito bites or other insect bites. It's really a matter of how your body reacts to the bedbug saliva when you're bitten. Two people can sleep on the same bedbug-infested mattress, and one can wake up without any signs of being bitten while the other is covered in bite marks.

Bedbugs Cannot Be Seen by the Naked Eye

While bedbugs are pretty small insects, they aren't microscopic. If you know where to look for them, you can definitely see them without the aid of a magnifier. The bedbug nymph is roughly the size of a poppy seed and grows larger from there. Bed bug adults measure a bit larger than 1/8th of an inch, or about the size of an apple seed or a lentil. The eggs, which are just the size of a pinhead, will be harder to see without magnification.

Bed bug nymphs progress through five juvenile stages (called instars) during which time they are miniature versions of the adults but different in coloration. All stages of life in a bedbug require blood feeding to move on to the next.

Bedbug Infestations Are Rare

Although bedbugs all but disappeared in developed countries in the 1930s and again in the 1980s, global bedbug infestations are increasing in the 21st century. Rises in bedbug activity have been seen on every continent except Antartica. In the United States, bedbugs are reported in all 50 states, and an estimated one in five Americans either have had a bedbug infestation in their house or know someone who has encountered them.

Today infestations are in offices and retail environments, in health and transportation sectors, and even in movie houses: basically, anywhere people sleep or sit. There have been an estimated 220 million bedbugs involved in human household infestations in the United States alone since 2000.

Bedbugs Are a Sign of a Dirty House

Although there is a great social stigma to having a bedbug infestation, bedbugs don't care how neat and tidy your house is, nor do they care if you're the best housekeeper on the block. As long as you have blood pumping through your veins, bedbugs will happily take up residence in your home. The same rule holds true for hotels and resorts. Whether a hotel has bedbugs has nothing to do with how clean or dirty the establishment is. Even a five-star resort can host bedbugs.

One thing to keep in mind, however, is that clutter can make it much more difficult to get rid of bedbugs once they're in your home because they'll have lots of places to hide.

Bedbugs Only Bite After Dark

While bedbugs prefer to do their dirty work under cover of darkness, the light won't stop a hungry bedbug from biting you. In desperation, some people try leaving all their lights on all night, hoping the bedbugs will stay hidden like cockroaches. All that will do is make you more sleep-deprived.

Bedbugs spend most of the time hidden away in aggregate communities. They only come out to feed once every three to seven days, usually from 1 to 5 a.m. They fully engorge themselves on your blood in 10 to 20 minutes, and then they walk back to their communities to digest their food. After a meal, adult bedbugs may increase in length by 30 to 50 percent and in weight by 150 to 200 percent.

Bedbugs Live in Mattresses

Bedbugs do hide in the seams and crevices of your mattress. Since these nocturnal insects feed on your blood, it is to their advantage to live close to the place where you spend the night. But that doesn't mean bedbugs only live in mattresses. Bedbugs inhabit carpets and couches, dressers and closets, and even places you'd never think to look, like picture frames and switch plate covers.


You Can Feel a Bedbug Bite

Bedbugs are very small and so are their bits, but bedbug saliva contains a substance that serves as a mild anesthetic, so when one bites you, it actually does you the favor of numbing your skin first. It's very unlikely that you'd ever feel a bedbug bite when it happens.

Later reactions to bites vary from individual to individual. Some people have no reactions at all; often the bites start out as small indistinct lesions about two-tenths of an inch (5 mm) in diameter, which may progress into large circular or ovoid welts. Some may grow to as big as .75 to 2.5 inches (2–6 cm) in diameter. If there are large numbers of bites, they can give the appearance of a generalized rash. They itch intensely, cause sleep deprivation, and can be associated with secondary bacterial infections as a consequence of scratching the bite site.

Bedbugs Jump From the Floor to Your Bed

Bedbugs aren't built for jumping. Bedbugs don't have legs adapted for jumping, like fleas or grasshoppers. Bedbugs don't have wings, either, so they can't fly. They can only walk for locomotion, so moving from the floor to the bed requires them to climb up the leg of a bed, or to scale any belongings or furniture you've placed near the bed.

This can work to your advantage if you're battling bedbugs, as you can create barriers to keep bedbugs from climbing onto your bed. Use double-sided tape on the bed legs, or place them in trays of water. Of course, if your bedspread touches the floor, the bedbugs can still climb into your bed, and bedbugs have been known to crawl up the wall to the ceiling, and then drop onto the bed.

Bedbugs Transmit Diseases to People.

Although bedbugs can and do carry infectious particles of a wide range of diseases, there is little danger of the viruses being transmitted to humans. So far, scientists have found no evidence that bedbugs are capable of transmitting diseases to human hosts. For this reason, they're considered a nuisance pest rather than a health threat.

When bedbug infestations started to rise in the U.S., many health departments and agencies were slow to respond to complaints about bedbugs, because they weren't considered a public health issue and resources weren't allocated for combating them.

Even though they don't transmit diseases, bedbugs still pose a health risk. Some people experience severe allergic reactions to bedbug bites, and people who are bitten can suffer from secondary infections of the bite sites. The emotional stress of dealing with a persistent bedbug infestation can also have a negative impact on your health.

Bedbugs Can Survive a Year Without a Meal

Technically, this is true. Under the right conditions, bedbugs have been known to survive as long as a year without a meal. Bedbugs, like all insects, are cold-blooded, so when temperatures drop, their body temperatures also decrease. If it gets cold enough, bedbug metabolism will slow down, and they'll stop eating temporarily.

However, it is highly unlikely that it would ever get cold enough in your home to trigger such a long period of inactivity, so for practical purposes, this statement is false. At normal room temperature, the bedbug might go as long as two to three months without taking a blood meal, but that's it.

Regularly feeding temperate climate bedbugs typically live up to 485 days in temperatures about 73 F (23 C). In fact, bedbugs require blood from vertebrates for survival, growth, and reproduction. Feeding is a requisite for mating, for giving birth, and for molting, and without it none of those things can take place.


  • "What You Should Know About Bedbugs," Cornell University Campus Life Management Office.
  • "Bedbugs: Biology and Control," North Carolina State University, accessed January 21, 2012.