How Bed Bugs Detect Humans
How to Find Bed Bugs
If you have a bed bug infestation, it is best to find it early, before the infestation becomes established or spreads. Treating a minor infestation, while an inconvenience, is far less costly and easier than treating the same infestation after it becomes more widespread.
However, low-level infestations are also much more challenging to find and correctly identify. Other insects, such as carpet beetles, can be easily mistaken for bed bugs. If you misidentify a bed bug infestation, it gives the bugs more time to spread to other areas of the house or hitchhike a ride to someone else’s house to start a new infestation. Learn about identifying bed bugs.
Bites on the skin are a poor indicator of a bed bug infestation. Bed bug bites can look like bites from other insects (such as mosquitoes or chiggers), rashes (such as eczema or fungal infections), or even hives. Some people do not react to bed bug bites at all.
Looking for Signs of Bed Bugs
A more accurate way to identify a possible infestation is to look for physical signs of bed bugs. When cleaning, changing bedding, or staying away from home, look for:
- Rusty or reddish stains on bed sheets or mattresses caused by bed bugs being crushed.
- Dark spots (about this size: •), which are bed bug excrement and may bleed on the fabric like a marker would.
- Eggs and eggshells, which are tiny (about 1mm) and pale yellow skins that nymphs shed as they grow larger.
- Live bed bugs.
Where Bed Bugs Hide
When not feeding, bed bugs hide in a variety of places. Around the bed, they can be found near the piping, seams and tags of the mattress and box spring, and in cracks on the bed frame and headboard.
If the room is heavily infested, you may find bed bugs:
- In the seams of chairs and couches, between cushions, in the folds of curtains.
- In drawer joints.
- In electrical receptacles and appliances.
- Under loose wall paper and wall hangings.
- At the junction where the wall and the ceiling meet.
- Even in the head of a screw.
Bed Bug Confidential: An Expert Explains How to Defend against the Dreaded Pests
Everything you ever wanted to know about bed bugs but were afraid to ask
- By Kate Wong on January 23, 2012
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Chances are, you or someone you know has had a run-in with bed bugs. It might have happened in a scrupulously clean bedroom. Or maybe it was a hotel room, office or college dorm. In the February issue ofScientific Americanentomologist Kenneth Haynes of the University of Kentucky explains how, after a lengthy absence, bed bugs are staging a comeback. The good news is scientists are intensively studying these insects, and their insights suggest novel ways of detecting the bugs and eradicating infestations. Some of those potential solutions are a long way off, however. In the meantime the best bet is to avoid bringing bed bugs home in the first place. I called Haynes to ask him how to do that and what to do if one suspects an infestation (eek!), among a bunch of other practical-minded questions.
Do bed bugs only feed on humans?
No. Bed bugs are also pests in poultry operations, and they’re known to parasitize bats. Some labs that study bed bugs rear them on guinea pigs and mice. The bugs might feed on cats and dogs. Fur is probably a barrier to them, but they could feed at any place on the body without fur. Bed bugs are not specific to humans, but they are adapted to parasitizing us.
Could you have a bed bug infestation in your home and not know it?
That’s very possible. I have heard of couples reporting that only one partner is getting bitten. The truth is that both are getting bitten, but only one has a reaction to the bites. Thirty percent of people or more don’t react to bed bug bites at all, and the elderly are less reactive than the rest of the population. Among those people who do react to the bites, most of them don’t respond to early bites, but develop a sensitivity to subsequent ones. Those individuals who are not sensitive to bed bug bites may not know they have an infestation. Because bed bugs are nocturnally active, it’s hard to see other signs of their presence—unless you’re accustomed to waking up at 3 A.M. and taking a census. With a huge infestation, bed bugs start to move away from the bed, so you’re more likely to see one in an exposed place during the day. In very severe infestations people can become anemic. That takes a lot of bugs though—maybe 100,000 feeding once a week or more.
Another clue to infestation is odor. Like many species of bugs, bed bugs release odors called alarm pheromones. When a group of bed bugs gets disturbed, you may get a whiff of that odor, which is similar to the odor stink bugs give off. At higher concentrations the odor is unpleasant. Some people say at low concentrations it’s a pleasant smell—like coriander. In fact, older literature refers to the bed bug as the coriander bug. I’ve tried to smell the coriander scent in bed bug alarm pheromones and have not been able to make the connection, however.
What can one do to avoid getting bed bugs?
The first thing is you have to be able to recognize and distinguish a bed bug from any other insect. Everything starts to look like a bed bug if you start to worry about them. An adult bed bug is about the size and shape of an apple seed. If it has not fed recently it will be flattened and brown. If it has fed it will be round in circumference and reddish. Immature bed bugs have a similar appearance to adults, with the smallest being the size of the head of a pin. You can then learn to look for their fecal spots, which can be easier to detect than the bugs themselves. Check your hotel rooms when you travel. And think twice before bringing home used furniture. If you are purchasing used furniture, ask the furniture store how they deal with bed bugs. If they have no plan whatsoever, that’s probably not a good sign. If you purchase used clothing, put it through a clothes dryer on a medium to high setting for a cycle as soon as you bring it home. And before you move into an apartment, ask the landlord whether there has been a bed bug infestation, or whether the building has ever been treated for bed bugs.
What should one do upon suspecting a bed bug infestation
The first question I would ask that person is, what makes you think you have bed bugs? A skin reaction alone does not necessarily indicate the presence of bed bugs. Other bugs, allergies and irritants in the environment can produce similar skin reactions. And it’s hard to confidently identify a bed bug bite because reactions vary from person to person. My next question would be, have you seen an insect in an area where you sleep and, if so, was it the correct size and shape to be a bed bug? Carpet beetles in an immature stage are commonly mistaken for bed bugs. The carpet beetle actually doesn’t look anything like a bed bug, but it is the right size. And it’s another common insect to have indoors around the bed. If you find an insect that you think is a bed bug, save it in a pill bottle or another container so its key characteristics won’t get crushed and a professional can identify it.
I wouldn’t try to get rid of an infestation on my own. I would call a pest control operator. A good pest control operator will spend a fair amount of time inspecting the place for evidence of bed bugs, and will educate the person on what makes it clear that it’s a bed bug infestation.
Once you have a suspicion or a confirmed infestation, do not spread things outside of the bedroom. Don’t take linens off the bed and go to sleep somewhere else—that will just move the infestation to other rooms. Ultimately pest control operators will tell you to put everything you can through the washer and dryer, since bed bugs cannot withstand high temperatures. I don’t think bed bugs would be able to survive solvent-based dry cleaning, but I don’t have any first-hand knowledge that that’s true. Unfortunately, dry cleaners and Laundromats can be places where people pick up bed bugs. I think it’s a low probability, but it only takes one adult female bed bug that has been mated to get an infestation going.
The safest and most effective approach to getting rid of bed bugs is heat treatment, in which a trained professional heats the home’s rooms one by one to a temperature of 50 degrees Celsius and sustains the heat for four hours. Heat does not penetrate well into wall voids, though, so desiccant dusts are often applied to those areas. No single technique can eliminate bed bugs—combinations of approaches are essential to getting the job done.
What are the mistakes people make in trying to get rid of bed bugs on their own, without professional help?
DIY approaches come with risk. It’s not uncommon for someone to use a pest-control bomb or fogger that is available over the counter. These don’t work well against bed bugs, according to research from Ohio State University. They can also expose people to toxic chemicals. Neither are over-the-counter aerosol insecticides effective against bed bugs. Most of these products have either pyrethrin or a pyrethroid as a main ingredient and those compounds have the same mode of action as DDT, which bed bugs have become resistant to. If you spray the bug directly you might kill it, but that is not going to get rid of the infestation. The problem is finding all the bed bugs. Some just can’t be reached with insecticide. It’s difficult for nonprofessionals to do anything more than kill what they can see, but that’s just the tip of the iceberg in terms of what’s there.
Some of the dusts that are available to consumers, such as diatomaceous earth, can help in this regard. Pest controllers will put dusts in wall voids and other places where pesticide won’t reach. What happens is the bugs will wander through the dust and pick up particles and be more vulnerable to desiccation after that exposure. But dusts will not solve the problem if deployed incorrectly, and if they are applied at too high a level they can cause breathing difficulties in some people.
The Internet abounds with so-called miracle cures for bed bugs. But bed bugs are hard to get rid of, so anything that advertises an immediate solution is not accurate—it’s snake oil. These "cures" have included (as reported by pest control operators who come in afterward to tackle bed bugs correctly) using bleach, ammonia and even DIY heat treatment, which carries fire risk.
Another solution you hear about is vacuuming. You can vacuum up a lot of insects, but eggs are harder to get, and vacuuming won’t in and of itself kill bed bugs. Indeed, vacuuming can end up spreading bed bugs to other rooms—when emptying the canister, for example. Pest control operators who use vacuums take measures to prevent bed bugs from escaping when the vacuum is emptied.
Encasing mattresses is one of many good parts of a solution, but it doesn’t get rid of the infestation. There are going to be other bugs away from the mattress, hiding nearby. What mattress covers are good at is entombing the sometimes large number of bed bugs that can live on a mattress. And because the covers tend to be uniform in color and don’t have a lot of seams that the bugs can hide in, it’s easier to see the insects.
Given that you work with bed bugs, how do you avoid bringing them home?
I have four risk factors. I work with bed bugs in a lab situation, so we have to take extreme precautions to prevent escapes there. I visit infested apartments sometimes. I travel a fair amount, so I may be exposed to bed bugs in hotels. And I’ve had college-age kids, who can bring bed bugs home from dorms.
In the lab we handle all the bed bugs in a specific room that we steam clean once a week, and we have double-stick tape barriers that they can’t walk through (as long as the adhesive remains dust-free). And the bed bugs themselves are enclosed in containers that they can’t get out of. We actually feed them inside those containers—we lay a blood reservoir against the cloth "lid" and the bed bugs have to push their mouthparts through the cloth into the reservoir to eat.
If I go to an infested apartment, then when I leave I check my shoes very carefully for bugs that may have crawled onto them. I also keep a change of clothes in my garage and put them on before entering my house. Once inside, I immediately put the clothes I wore to the infested apartment in the dryer, which is located in a room just off the garage.
When staying in a hotel, I check the bed before I bring the suitcase into the sleeping part of the room so that if I have to ask the manager for another room, then I haven’t exposed my suitcase to the bugs. When settling in, I put my suitcase up on the suitcase stand or the desktop so that any bugs are less likely to crawl into it. An extreme measure would be putting the suitcase in the tub. If it’s a porcelain tub, bed bugs would have a hard time crawling up it. It’s also unlikely that they would randomly crawl up a tub, because it’s not near the bed. But if I don’t see bed bugs in the room when I inspect it, I just put my suitcase on the stand because I know the probability is really low that a bug is going to crawl up the stand and into my suitcase. I keep my clothes in the suitcase or hang them in the closet—I don’t leave them on the floor because wandering bed bugs might crawl into them.
I actually haven’t found bed bugs in my hotel rooms, but I’ve seen them in other peoples’ rooms. Enough of my students and postdocs have found them that I’m surprised I haven’t seen them yet in a room where I’m staying.
How should one check a hotel room for bed bugs?
Bring a little flashlight—hotel room lighting is always pretty poor and the dimmer the lighting, the harder it is to see small bed bugs or their fecal spots. I would pull back the bed covers and look all around the head of the bed. Pull back the sheets, too, and look at mattress seams and edges that are exposed. bed bugs love to hide under mattress tags. Look all around the box springs, too. If there’s a dust ruffle, pull it up and look under it as much as possible. Look for moving bugs and stationary, hiding bugs.
The space behind the headboard is prime bed bug territory. Most headboards are hanging on the wall. If my wife is with me, we’ll remove it and look behind it. This exposes a lot of possible bed bug territory. Even if you don’t remove headboard, look around it. Or if you move the bed out from wall, look at the wall under the headboard.
Bed bugs could also be at the foot of the bed, but they’re more likely to reside at the head of the bed. The foot of the bed, if the sheets are tucked in, doesn’t allow bed bugs easy access to a sleeping host. The bugs would have to come up to the head of the bed to get you, and they typically minimize the distance to the host.
All of the stages of bed bugs are visible, at least if you don’t need reading glasses and you have a sufficient amount of light. So if you’re looking closely enough, you can even see bugs in the nymphal first instar stage. A fecal spot, for its part, can be as large as a bed bug itself in terms of the area it covers. The spots are basically digested blood, so most are dark in color. On a white mattress, they stand out pretty well.
Are there tactics that professional exterminators use that don’t work?
No one tactic alone will be effective. A good pest control operator will develop a strategy to deal with the bed bugs that takes the particulars of the setting into account, and will return several times to check on progress. Dry ice sprays that freeze bed bugs have limited potential to reach hidden bugs. Steam has somewhat better penetrating ability. The downside of steam is that it leaves moisture behind. Dry ice doesn’t leave any residue at all. Vacuuming has a role, but it has limitations, too. Some insecticides leave behind deposits that are slow to act but are effective in the long-term. Other insecticides kill on contact, but only reach insects that are in view. Insecticide resistance makes the choice of tactics more difficult.
An important thing to remember is that good professional pest controllers do get rid of bed bugs. The fine line that bed bug experts have to walk in talking to the public is the line where the anxiety and depression and so forth that can result from thinking about bed bugs too much can cause more problems than the bugs themselves would.
How to Detect Bed Bugs
Detecting bed bugs can be difficult, as they are small in size and able to hide in tiny cracks and crevices. However, evidence of a bed bug infestation may be found in bedding and on mattresses. Live bed bugs leave clusters of dark brown or black spots of dried excrement on infested surfaces. Bed bugs also exude a subtle, sweet, musty odor.
Bed Bug Cluster
Where to Check for Bed Bugs
Bed bugs usually are found close to where people spend much of their time, and since bed bugs have flattened bodies, they like to get into small cracks and crevice near where people sleep. Examples include mattresses, box springs, headboards, footboards, bed frames and other furniture that is within 5-8 feet of the bed. Other common locations are cracks and gaps behind wall outlets, floor molding, window and door molding and where carpet edges meet the wall. Bed bugs have been known to occur in many different locations if their population is large and they have dispersed from their more common areas to areas where they are normally less likely to be found.
Bed bugs are easily transported into previously non-infested dwellings.
If you have detected a bed bug infestation within your home, contact a pest control professional to discuss treatment options.
Bed Bug Control
Cimex lectularius L.
Learn what bed bugs look like, and how to detect if you have a bed bug Infestation.
Find out how bed bugs infiltrate your home and where they are attracted to.
Learn about bed bug bites. their feces and how they can impact your health.
Learn how Orkin handles bed bugs, homeopathic cures and the cost of bed bug extermination services.
In this Article
In this Article
In this Article
Bedbugs are small, oval, brownish insects that live on the blood of animals or humans. Adult bedbugs have flat bodies about the size of an apple seed. After feeding, however, their bodies swell and are a reddish color.
Bedbugs do not fly, but they can move quickly over floors, walls, and ceilings. Female bedbugs may lay hundreds of eggs, each of which is about the size of a speck of dust, over a lifetime.
Immature bedbugs, called nymphs, shed their skins five times before reaching maturity and require a meal of blood before each shedding. Under favorable conditions the bugs can develop fully in as little as a month and produce three or more generations per year.
Although they are a nuisance, they are not thought to transmit diseases.
Where Bed Bugs Hide
Bedbugs may enter your home undetected through luggage, clothing, used beds and couches, and other items. Their flattened bodies make it possible for them to fit into tiny spaces, about the width of a credit card. Bedbugs do not have nests like ants or bees, but tend to live in groups in hiding places. Their initial hiding places are typically in mattresses, box springs, bed frames, and headboards where they have easy access to people to bite in the night.
Over time, however, they may scatter through the bedroom, moving into any crevice or protected location. They may also spread to nearby rooms or apartments.
Because bedbugs live solely on blood, having them in your home is not a sign of dirtiness. You are as likely to find them in immaculate homes and hotel rooms as in filthy ones.
When Bedbugs Bite
Bedbugs are active mainly at night and usually bite people while they are sleeping. They feed by piercing the skin and withdrawing blood through an elongated beak. The bugs feed from three to 10 minutes to become engorged and then crawl away unnoticed.
Most bedbug bites are painless at first, but later turn into itchy welts. Unlike flea bites that are mainly around the ankles, bedbug bites are on any area of skin exposed while sleeping. Also, the bites do not have a red spot in the center like flea bites do.
People who don’t realize they have a bedbug infestation may attribute the itching and welts to other causes, such as mosquitoes. To confirm bedbug bites, you must find and identify the bugs themselves.
Signs of Infestation
If you wake up with itchy areas you didn’t have when you went to sleep, you may have bedbugs, particularly if you got a used bed or other used furniture around the time the bites started. Other signs that you have bedbugs include:
- Blood stains on your sheets or pillowcases
- Dark or rusty spots of bedbug excrement on sheets and mattresses, bed clothes, and walls
- Bedbug fecal spots, egg shells, or shed skins in areas where bedbugs hide
- An offensive, musty odor from the bugs’ scent glands
If you suspect an infestation, remove all bedding and check it carefully for signs of the bugs or their excrement. Remove the dust cover over the bottom of the box springs and examine the seams in the wood framing. Peel back the fabric where it is stapled to the wood frame.
Also, check the area around the bed, including inside books, telephones or radios, the edge of the carpet, and even in electrical outlets. Check your closet, because bedbugs can attach to clothing. If you are uncertain about signs of bedbugs, call an exterminator, who will know what to look for.
If you find signs of infestation, begin steps to get rid of the bugs and prevent their return.
Getting rid of bedbugs begins with cleaning up the places where bedbugs live. This should include the following:
- Clean bedding, linens, curtains, and clothing in hot water and dry them on the highest dryer setting. Place stuffed animals, shoes, and other items that can’t be washed in the dryer and run on high for 30 minutes.
- Use a stiff brush to scrub mattress seams to remove bedbugs and their eggs before vacuuming.
- Vacuum your bed and surrounding area frequently. After vacuuming, immediately place the vacuum cleaner bag in a plastic bag and place in garbage can outdoors.
- Encase mattress and box springs with a tightly woven, zippered cover to keep bedbugs from entering or escaping. Bedbugs may live up to a year without feeding, so keep the cover on your mattress for at least a year to make sure all bugs in the mattress are dead.
- Repair cracks in plaster and glue down peeling wallpaper to get rid of places bedbugs can hide.
- Get rid of clutter around the bed.
If your mattress is infested, you may want to get rid of it and get a new one, but take care to rid the rest of your home of bedbugs or they will infest your new mattress.
While cleaning up infested areas will be helpful in controlling bedbugs, getting rid of them usually requires chemical treatments. Because treating your bed and bedroom with insecticides can be harmful, it is important to use products that can be used safely in bedrooms. Do not treat mattresses and bedding unless the label specifically says you can use them on bedding.
Generally it is safest and most effective to hire an experienced pest control professional for bedbug extermination.
University of Kentucky College of Agriculture: "Bed Bugs."
Ohio State University Extension Fact Sheet: "Bed Bugs."
The New York City Department of Heath and Mental Hygiene: "Stop Bed Bugs Safely."
University of Nebraska–Lincoln Extension Lancaster County: "Managing Bed Bugs."
9 SYMPTOMS AND SIGNS OF BED BUGS
Bed bugs are a nasty and uncomfortable problem. Signs and symptoms of bed bugs can be hard to detect at first, and even trickier to treat. To the untrained eye, bed bug bites can be confused with those of other biting insects.
Here are nine easy signs help you know if you have a bed bug problem.
RED, ITCHY BITES
People don’t often consider bed bugs until they’ve left their mark. The appearance of flat, red welts in zigzag lines or small clusters is a key sign of bed bugs on humans. Bed bugs can also leave their bites in straight rows and, while they don’t spread diseases to humans, their bites are quite irritating and scratching them can lead to bleeding and infection.
Bed bugs are most often found in the bed, where humans spend most of their nights. It makes logical sense for bed bugs to be most active at night while humans are in bed with them. Should you find yourself developing those itchy welts while laying in bed sleeping (or trying to sleep), it’s likely bed bugs are the problem.
MARKED ARMS AND SHOULDERS
Bed bugs tend to feed on exposed skin such as that on your arms and shoulders, which you may tend to leave uncovered while sleeping. This is different from, say, fleas and chiggers, which tend to bite around the ankles.
A BUGGY BED
The first sign of a bed bug problem is obvious: the bed. After bed bugs feed on humans, they’ll leave behind blood stains resembling small rust spots. These will usually be found near the corners and edges of the bed. Bed bugs also shed their skin, or molt, several times as they mature, so you may find their oval brown exoskeletons during your search.
THE NOSE HAS IT
A strong, unpleasant, musty odor like that of a wet towel is another common bed bug symptom. Bed bugs release pheromones, and when in large numbers, the smell can be quite strong. Should you find your bedroom smelling like a dirty locker room, you may want to perform an inspection.
Remember, bed bugs aren’t confined to your home. They can be found wherever you sleep, including hotel rooms.
Here are some quick inspection tips to help you avoid a serious problem, whether on the road or at home:
INSPECT THE BED
Strip the mattress and box spring and thoroughly inspect the corners and seams. Use a magnifying glass and a flashlight. You’re looking for rust-colored, reddish-brown blood stains and/or small brown ovals (molted bed bug skin).
INSPECT THE ROOM
After searching the bed, it’s time to move to the rest of the room. Check anything upholstered, including chairs, couches, curtains and the edges of the carpet. Look in and behind dressers, underneath the bed and if possible, behind the headboard. Always be on the lookout for the signature reddish-brown spots.
OPEN THE CLOSET
Bed bugs can also cling to clothing, which is how they can travel and spread so adeptly. Be sure to look in your closets and check your clothing thoroughly. Bed bugs on clothes means bed bugs on humans.
USE YOUR NOSE
As stated above, one way detect bed bugs is their smell. The scent of their pheromones can be quite strong. It’s often described as a musty odor.
Since it’s possible for people to go for long periods without being aware they have a bed bug infestation, knowing the key bed bug symptoms and how to find these pests will go a long way in combating them.