How Does Bed Bug Bites Work
When Treatments Don’t Work
If the goal is to eliminate bed bugs, the job has to be done correctly. Bed bugs are so small that they can live in a crack the width of a credit card, increasing the control challenge.
Pesticides often are an important part of a control strategy but they must be used properly for the treatment to work. There can be many reasons for failure of a pesticide treatment to completely control the bed bugs, including:
- Not finding all the bed bugs.
- Inadequately preparing area (failure to remove clutter, seal cracks and crevices, etc.).
- Overlooking treatment of any of the known resting areas (bed bugs may rest or hide in hampers, bed frames, even furniture).
- Failing to treat nearby areas where bed bugs may have migrated (adjacent rooms or other apartments in multi-dwelling housing).
- Disregarding recommended label rates (applying pesticides at too low a rate may not kill bugs and may speed up development of resistance to that chemical).
- Not following up on treatment in an appropriate timeframe (many pesticides will not kill eggs, so treatment must be repeated after the eggs hatch, or the infestation will not be controlled).
- Not allowing enough time for a pesticide to work (some pesticides, such as drying agents or growth regulators, may be effective but take some time to kill the population).
- Bed bugs becoming resistant to a specific type of pesticide.
- As insects, such as bed bugs, are exposed to a pesticide over time, the most susceptible ones are killed first, leaving only the less susceptible ones to breed. This can result in a rapid decline in relative effectiveness of the pesticide.
Pesticide Resistance as a Cause of Treatment Failure
While there is evidence of resistance in some populations to certain types of pesticides, pesticide resistance can only be verified in laboratory tests. Researchers are currently trying to determine the scope of the resistance problem, which will vary from community to community. This research will support the development and use of effective control strategies.
Because of the potential for resistance, homeowners and others trying to control bed bug infestations must always use pesticides appropriately and according to the label. It is also important to:
- be vigilant in surveillance, identification, and monitoring efforts;
- hire trained, experienced, and reputable pest management professionals; and
- use a comprehensive approach.
For example, you may wish to:
- choose different types of pesticides from the list of currently labeled ones for sequential treatments; or
- use pesticides for which insect resistance has not yet been reported, such as diatomaceous earth, in combination with other control techniques.
Remember, as illustrated in the list above, resistance is only one of many possible causes of a treatment failure. All possibilities must be explored in any situation.
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Bedbugs are small insects that often live on furniture or bedding. Their bites can be itchy, but do not usually cause other health problems.
Check if it’s bedbugs
Jeff March / Alamy Stock Photo
Bedbugs can hide in many places, including on bed frames, mattresses, clothing, furniture, behind pictures and under loose wallpaper.
Signs of bedbugs include:
- bites – often on areas exposed while sleeping, like the face, neck and arms
- spots of blood on your bedding – from the bites or from squashing a bedbug
- small brown spots on bedding or furniture (bedbug poo)
Bedbug bites can be red and itchy. They’re often in a line or cluster.
Otto Pleska / Alamy Stock Photo
Some people have a reaction to the bites. They can be very itchy and there may be painful swelling.
How you can treat bedbug bites
Bedbug bites usually clear up on their own in a week or so.
Things you can do include:
- putting something cool, like a clean, damp cloth, on the affected area to help with the itching and any swelling
- keeping the affected area clean
- not scratching the bites to avoid getting an infection
You can ask a pharmacist about:
- using a mild steroid cream like hydrocortisone cream to ease bedbug bites (children under 10 and pregnant women should get advice from a doctor before using hydrocortisone cream)
- antihistamines – these may help if the bites are very itchy and you’re unable to sleep
Non-urgent advice: See a GP if:
- the bites are still very painful, swollen or itchy after trying treatments from a pharmacist
- the redness around the bites is spreading
You may have an infection and need treatment with antibiotics.
Coronavirus update: how to contact a GP
It’s still important to get help from a GP if you need it. To contact your GP surgery:
- visit their website
- use the NHS App
- call them
How to get rid of bedbugs
contact your local council or pest control service – it’s unlikely you’ll be able to get rid of bedbugs yourself because they can be resistant to some insecticides
wash affected bedding and clothing – use a hot wash (60C) or tumble dry on a hot setting for at least 30 minutes
put affected clothing and bedding in a plastic bag and put it in the freezer (-16C) for 4 days (alternative to hot washing)
clean and vacuum regularly – bedbugs are found in both clean and dirty places, but regular cleaning will help you spot them early
do not keep clutter around your bed
do not bring secondhand furniture indoors without carefully checking it first
do not take luggage or clothing indoors without checking it carefully if you have come from somewhere where you know there were bedbugs
Page last reviewed: 21 January 2019
Next review due: 21 January 2022
Bed Bugs FAQs
What are bed bugs?
Bed bugs (Cimex lectularius) are small, flat, parasitic insects that feed solely on the blood of people and animals while they sleep. Bed bugs are reddish-brown in color, wingless, range from 1mm to 7mm (roughly the size of Lincoln’s head on a penny), and can live several months without a blood meal.
Where are bed bugs found?
Bed bugs are found across the globe from North and South America, to Africa, Asia and Europe. Although the presence of bed bugs has traditionally been seen as a problem in developing countries, it has recently been spreading rapidly in parts of the United States, Canada, the United Kingdom, and other parts of Europe. Bed bugs have been found in five-star hotels and resorts and their presence is not determined by the cleanliness of the living conditions where they are found.
Bed bug infestations usually occur around or near the areas where people sleep. These areas include apartments, shelters, rooming houses, hotels, cruise ships, buses, trains, and dorm rooms. They hide during the day in places such as seams of mattresses, box springs, bed frames, headboards, dresser tables, inside cracks or crevices, behind wallpaper, or any other clutter or objects around a bed. Bed bugs have been shown to be able to travel over 100 feet in a night but tend to live within 8 feet of where people sleep.
Do bed bugs spread disease?
Bed bugs are not known to spread disease. Bed bugs can be an annoyance because their presence may cause itching and loss of sleep. Sometimes the itching can lead to excessive scratching that can sometimes increase the chance of a secondary skin infection.
What health risks do bed bugs pose?
A bed bug bite affects each person differently. Bite responses can range from an absence of any physical signs of the bite, to a small bite mark, to a serious allergic reaction. Bed bugs are not considered to be dangerous; however, an allergic reaction to several bites may need medical attention.
What are the signs and symptoms of a bed bug infestation?
One of the easiest ways to identify a bed bug infestation is by the tell-tale bite marks on the face, neck, arms, hands, or any other body parts while sleeping. However, these bite marks may take as long as 14 days to develop in some people so it is important to look for other clues when determining if bed bugs have infested an area. These signs include:
- the bed bugs’ exoskeletons after molting,
- bed bugs in the fold of mattresses and sheets,
- rusty–colored blood spots due to their blood-filled fecal material that they excrete on the mattress or nearby furniture, and
- a sweet musty odor.
How do I know if I’ve been bitten by a bed bug?
It is hard to tell if you’ve been bitten by a bed bug unless you find bed bugs or signs of infestation. When bed bugs bite, they inject an anesthetic and an anticoagulant that prevents a person from realizing they are being bitten. Most people do not realize they have been bitten until bite marks appear anywhere from one to several days after the initial bite. The bite marks are similar to that of a mosquito or a flea — a slightly swollen and red area that may itch and be irritating. The bite marks may be random or appear in a straight line. Other symptoms of bed bug bites include insomnia, anxiety, and skin problems that arise from profuse scratching of the bites.
Because bed bug bites affect everyone differently, some people may have no reaction and will not develop bite marks or any other visible signs of being bitten. Other people may be allergic to the bed bugs and can react adversely to the bites. These allergic symptoms can include enlarged bite marks, painful swellings at the bite site, and, on rare occasions, anaphylaxis.
How did I get bed bugs?
Bed bugs are experts at hiding. Their slim flat bodies allow them to fit into the smallest of spaces and stay there for long periods of time, even without a blood meal. Bed bugs are usually transported from place to place as people travel. The bed bugs travel in the seams and folds of luggage, overnight bags, folded clothes, bedding, furniture, and anywhere else where they can hide. Most people do not realize they are transporting stow-away bed bugs as they travel from location to location, infecting areas as they travel.
Who is at risk for getting bed bugs?
Everyone is at risk for getting bed bugs when visiting an infected area. However, anyone who travels frequently and shares living and sleeping quarters where other people have previously slept has a higher risk of being bitten and or spreading a bed bug infestation.
How are bed bugs treated and prevented?
Bed bug bites usually do not pose a serious medical threat. The best way to treat a bite is to avoid scratching the area and apply antiseptic creams or lotions and take an antihistamine. Bed bug infestations are commonly treated by insecticide spraying. If you suspect that you have an infestation, contact your landlord or professional pest control company that is experienced with treating bed bugs. The best way to prevent bed bugs is regular inspection for the signs of an infestation.
This information is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the parasites described above or think that you may have a parasitic infection, consult a health care provider.
Bedbug Treatments: Facts and Myths
What works and what doesn’t to get rid of a bedbug infestation?
- B.A., Political Science, Rutgers University
Bedbugs aren’t easy to get rid of, and in desperation, you might be tempted to try the first remedy you read about online. Unfortunately, many of these methods are ineffective—and some can even be dangerous. If you ever find yourself in a battle with these pesky varmints, make sure to separate fact from fiction before you fight back. Knowing what works and what doesn’t will save you time, money, and aggravation.
Fact: You’ll Need to Call Pest Control
The most effective means of getting rid of bedbugs is to call in a trained professional and have them apply a pesticide. Many pros also recommend giving your home a thorough cleaning because bedbugs can hide anywhere and pesticides can’t be applied to everything you own. You’ll need to get rid of clutter and launder anything washable in hot water. You may also need to steam-clean your carpets and furniture.
Fact: Pesticides Don’t Always Work
Bugs can develop resistance to pesticides over time, especially if they’re overapplied. Chemicals, such as deltamethrin, that were once commonly used to combat certain pests are no longer effective. According to research from 2017, bedbugs may be developing resistance to pyrethrums, the most common chemical used to combat them.
Fact: You May Not Have to Toss Your Furniture
If the infestation is caught early, a professional pest control application and diligent cleaning should remove these critters from your furniture. More severe infestations are another matter. If your mattress is torn or separated at the seams, bedbugs have likely moved inside, making treatment near impossible. In such circumstances, replacement may be your only option.
Fact: Mattress Covers Work
A number of companies make bedbug resistant mattress covers that form an impenetrable barrier around the exterior of your mattress. If you’ve had your home treated for a bedbug infestation, using a mattress cover can prevent any remaining bugs in your mattress from getting out and biting you.
Myth: You Can Kill Bedbugs With Bug Bombs
Bug bombs, or total room foggers, release a pesticide into the air in your home. Most bug bombs contain pyrethrin, one of the chemicals used to combat bedbugs, so you might think this product is an effective way to eliminate an infestation. Not so.
First of all, bedbugs (and other crawling insects) typically flee when pesticide is released, heading for cover in the deepest, most inaccessible crevices of your home. Second, effective treatment requires directed applications in all the places where bedbugs hide: behind moldings and casements, inside electrical boxes, or inside mattresses, for example. Chemicals released by a bomb simply can’t reach such places adequately to kill all the bedbugs in your home.
Myth: Bedbug Sniffing Dogs are Highly Effective
While companies that use bug-sniffing dogs may claim a success rate of over 90%, the truth is, there hasn’t been a lot of testing to see if these claims are true. (And at between $500 and $1,000 for their services, that’s an expensive "maybe it works and maybe it doesn’t.") In 2011, two researchers at Rutgers University did put some bedbug-sniffing dogs through their paces in real apartment buildings, and the results were nowhere near as effective as advertised. The accuracy of the dogs’ detecting abilities averaged just 43%.
Myth: You Can Kill Bedbugs by Turning Up The Heat
Heat treatments do kill bed bugs effectively, but simply turning up your thermostat isnota heat treatment. To roast bedbugs in your home, you’d have to heat the entire house evenly to over 120° F for at least an hour (including the voids between interior and exterior walls and the insides of your furniture). No home heating system is designed to do that. Professional heat treatments usually involve sealing your home and using multiple heat sources throughout the house to raise the temperature.
Myth: You Can Kill Bedbugs by Turing Off The Heat
Temperatures below 32° F can and do kill bed bugs outside of the home—if temperatures remain below freezing for a prolonged period of time. but who wants to live in a freezing house? Moving out for the two to three months that it would take to starve bed bugs of their source of food (you) is equally impractical.
What Good Is a Bed Bug Mattress Cover?
Eve Mattress/Wikimedia Commons/CC BY 4.0
- B.A., Political Science, Rutgers University
Bed bugs are a pervasive pest that can find their way into any home by unwitting hosts. They can do this simply by hitching a ride in suitcases if you visit a hotel with an infestation, transferring onto your clothes from a movie theater seat, or traveling on visitors who come into your home. These bugs are erroneously associated with pests that only live in filthy living conditions. In fact, they can live and breed anywhere, including inside clean, uncluttered homes.
To protect your mattress from an infestation or to curb a mattress infestation that may have occurred, you can purchase a bed bug mattress encasement to trap the bugs inside the encasement or discourage bugs from making a permanent home in your bed. While mattress covers can provide some protection, however, you need to do much more to guarantee a bed-bug-free environment.
What Is a Bed Bug?
The common parasitic bed bug, from the cimicid family, feeds on human blood usually during the nighttime hours when humans are sleeping. Bed bugs can be seen with the naked eye and are roughly the size of a lentil. They have round brown or red bodies and are easy to spot on white surfaces. They prefer to live close to their human food source and make their homes in beds. Between 85 and 90 percent of the bed bugs in an infested home are typically found on or within 15 feet of the bed.
Bed bugs do bite; they actually saw into their host’s body and feed off their blood. While bed bugs don’t carry disease, their bites can cause blisters and itching, particularly for people with allergies. Bed bugs are very hard to control. Once they’ve infested a home, getting rid of them can be a challenge.
The Benefits of Mattress Covers
Most people are familiar with mattress covers. They are usually designed like a bottom sheet and provide protection for the top of a mattress. Ordinary mattress covers do little or nothing to stop bed bugs. Mattress encasements, however, can help minimize an infestation.
A mattress encasement is a tightly-woven fabric case that surrounds your mattress and box spring. Once it is installed, bed bugs already in the mattress cannot escape or breed, and will eventually die inside the encasement. Any bed bugs left outside the encasement will be easy to spot and remove. They will find no creases or hiding places where they can breed.
Mattress encasements not only repel and stifle bed bugs, but they can also provide a variety of other benefits. For example:
- A good mattress encasement can protect against dust mites and other pests as well as bed bugs.
- Most mattress encasements are waterproof, meaning that they will protect your mattress and box spring from spills and leaks.
- Mattress encasements can eliminate the risk of infestation if used with a new mattress and box spring.
Buying Mattress Encasements
Bed bug mattress encasements can be purchased for as little as $20, though you may wish to explore the more expensive options, as they are more likely to be reliable, sturdy, and bug-proof. It’s possible to purchase a pesticide-treated encasement, but the potential health hazards outweigh the slight increase in protection from insects.
Many pest control supply companies sell mattress encasements online. If you plan to purchase a bed bug mattress protector, make sure you choose one that is specifically designed for bed bugs. There are special features, such as bugproof zippers, different materials, and chemically-treated covers, that you can consider at the time of purchase. Do check the reviews to be sure you’re purchasing a product that is reliable and well-made. Another consideration is noise, as some encasements are made of fabric that crinkles as you move in bed. This could interfere with your sleep.
Even after you install your encasement, remember that adult bed bugs can live for well over a year without a blood meal. Leave the encasement on for at least that long or for the life of your mattress to be sure all resident bed bugs are dead and there are no new infestations of your mattress occur. Meanwhile, if your home is infested, you need to hire a pest management company to completely eradicate the bed bugs.