Melody is a volunteer for the Center for Disease and Control Prevention. She enjoys sharing her personal experience with others.
Differentiating Bug Bites
Bed Bug vs. Mosquito Bites
The difference between bed bug bites and mosquito bites is not always clear. What you need to know is that mosquito bites are commonly mistaken for bed bug bites, especially if the bites happen in bed at night.
Both creatures bites can induce allergic reactions. They appear immediately after exposure or later, as body chemistry affects the timing of the reaction. The comparison between the two might surprise you.
What also might surprise you is that mosquito bites are far more dangerous than bed bug bites. More people are spending times outdoors after a long Covid-19 caused pandemic. With this comes exposure to biting pets and plants. Both which cause rashes.
Mosquito bites appear in isolation, grow quickly, and resolve themselves. It's less likely to be bed bugs when there are only a few red areas. Resist the urge to scratch to prevent misdiagnosis of your rash.
The diameter of the bite depends on the person, the size of the mosquito, and length of time the mosquitos labium (mouth tubule) pierces the skin. However, the bites can get quite large. Unlike bed bug bites, irritation almost always begins at the time of the bite.
According to the Mayo Clinic, the symptoms of a mosquito bite are:
- Pale bump that appears lighter than the surrounding skin.
- The area around the bite may appear red.
- Initially, a soft bump that turns hard when scratched.
- The bump may turn red.
Other questions related to mosquito bites vs bed bug bites:
- Have you been outdoors a lot? (If so, it's more likely a mosquito.)
- Did you wear DEET bug spray? (works on mosquitos, gnats, and spiders but not on bed bugs.)
- Have you seen black, red, or brown smudges on bed sheets? (These may be bloody signs of bed bug bites.)
Bed Bug Bites
There are lots of pictures on the web to show you what bed bug bites look like. This rash can be clustered, red and unraised. Bed bug bites develop more slowly than that of mosquitoes, spiders, or fleas. If the bites linger for weeks or return quickly, AND you see strange bugs in bed at night, you might have bed bugs.
Bites almost always appear in clusters. Sometimes, they don't look like bites or a rash at all. Instead, they may look like welts. The odd thing about bed bugs is that some people never develop a rash.
These bloodsuckers split each feeding session into courses. One of these tiny vampires causes three red dots during its night meal. Attuned to exhaled carbon dioxide, the location of the bites may be consistent with bed bugs. Bed bugs are usually found near the head of the bed and spread from there.
Inspect the entire bed using your rash as a clue. For example, if you sleep on your back, on the left side of the bed, then check the mattress edges in that location.
Be cautious about self-diagnosing bed bug bites. Look for live specimens, clusters of bed bugs, dead bugs, discarded exoskeletons, or bug feces (rusty-looking stains). Check your bed, furniture, and car.
Read More From Youmemindbody
Bite Comparison Table: Spiders, Mosquitos and Bed Bugs
|Spider Bite||Mosquito Bite||Bed Bug Bite|
What you feel at time of bite
Bite feels like a sting, or is not felt.
Bite starts to itch immediately.
Not felt until hours or days later.
When you'll notice something
Immediate skin discoloration after bite.
Inset bite that turns red right away.
Does not turn red until anticoagulant wears off.
Number of bites that occur at once
Bites are usually singular, or dual.
Bites may be close by coincidence only.
Bites come in groups of three, unless bugs were interrupted while feeding.
Appearance over time
Usually has redness and is accompanied by puncture wounds from fangs.
Raised welt or rash that grows quickly.
After a few hours, each bite turns into a red circle, or dot.
What it looks like at the center
Center is red, with two small holes (bite itself).
Center is white at onset.
Center is red, and uniform with rest of rash. They are never white.
Who experiences a reaction?
Rash caused by venom.
Almost everyone bit by mosquitoes has a reaction.
Only some people get a rash. Some have no symptoms.
Common bite location
No specific body part is preferred.
Bites happen anywhere on uncovered skin, with mosquitoes preferring the upper torso.
Bed bugs are attracted to carbon dioxide (we breath this out), so most bites are near the head (but can be anywhere).
How long reaction takes to develop
Can take minutes to hours to develop symptoms.
Reaction happens in minutes.
The reaction may take as long as 14 days to develop in some people, and appears instantly on others.
Level of danger
Some venemous spider bites can be life-threatening.
Mosquito bites are an annoyance to all, but can be serious to those who are allergic.
Bed bug bites may rarely spread disease, and are not life-threatening.
Cause of bite
Bite caused by a pair of fangs.
Bite caused by needle-like tube called a labium.
Bite caused by two tubular mouthpieces.
Substance that is injected
Contains anticoagulant and enzymes.
Bite introduces anticoagulant, and brief skin numbing agent.
Bite contains a longer lasting pain killer, skin numbing agent and anti-coagulants.
What kind of creature
Not an insect an arachnid.
Is considered to be an insect bite.
Bite comes from an insect.
Many spider bites can be treated on your own at home. However, venomous spider bites can be painful and even deadly, and can require medical treatment.
Mosquito bites can be treated with home remedies, and almost never need medical treatment.
Bed bug bites are almost never treated by a doctor, and can be treated at home.
Time of year most common
Can happen any time of year, even in winter. Spiders find homes in houses and garages.
Bites only appear in spring, fall and summer. Where it gets cold, mosquitoes are not a problem in winter.
Happens year round. However, bed bugs are less active in extreme cold; few bites happen during winter.
Mosquitoes, Bed bugs , and Covid-19
Don't fall for any scams. Neither the CDC or researches truly know whether or not mosquitoes and bed bugs can transmit covid-19. The good news is that they do not believe that this is a method of transmission that we should worry about. well that is good news, the truth is there just hasn't been enough time or research to really understand whether or not blood-sucking bugs can give you covid-19.
Questions to Ask About Bug Bites
You may feel worried about your bite, but don't panic. First, do a self-check and determine if you are having a serious reaction. If yes, then call your doctor right away. Otherwise, become an investigator. Were you bit by a spider? A circular bug? Do you live in an area with dangerous bugs and spiders?
Hopefully you can rule out poisonous plants, or venomous animals. Some bugs are not as dangerous as perceived, For example, bud bugs don't spread diseases, but can cause severe allergic reaction in some people.
On the other hand, fleas and mosquitos do cause disease. It makes you wish there was a definitive way tell which insect or arachnid bit you. We sometimes have to be detectives so we can gather all the clues to answer the question once and for all.
Questions That Help Identify Bug Bites:
- What location on the body is the bite? Is it localized to one area?
- What part of my body is the bite limited to?
- Is the bite raised or flat?
- Are the bites in clusters?
- What season is it? It's unlikely for mosquitoes to bite in winter.
- Where did exposure happen?
- How long has the rash lasted?
- Does it come and go?
- Have I been outside or spending time at others' homes?
- Does my home show signs of infestation?
- Do you have previous skin conditions?
- Are there local public health warnings about a certain pest?
- Does your pet have fleas?
- How big is the rash?
- Does it itch, burn, or is it painful?
Answering these questions may help you discover the culprit and might be information your doctor needs.
Were You Bit by a Bed Bug?
It is not easy to tell the difference between mosquito, bud bug, spider, flea, and other kinds of bug bites—not to mention fungal rashes, allergic reactions, and poison oak and ivy. Mystery bites are alarming because of their similarities, and make a person worry.
Don't worry, there are characteristic differences that the average joe can spot, so you can rule out (or in) bed bugs. With thousands of rashes existing worldwide, you may even need a doctor to help identify your rash. With the current, 2019, outbreak of Mumps and measles, you need to ask your doctor about any suspicious rash, as well as check on your immunities (even if you are older).
Unfortunately, your doctor can't always tell what bit you by looking at the bite. But it's important to rule out a contagious disease quickly. When you show up to your doctors office with a rash, they will want to gather as much information as they can. If you can present them with a picture the bug that bit you, then you are likely to get a positive identification.
They may prescribe hydrocortisone cream for irritation. Chronic hives and allergic bug rashes may require more powerful treatment such as injectable anti-inflammatories such as Xolair or Colchicine. If you have a rash, and don't know what it is, then be very proactive.
Bed Bug Bites Do Itch, Worse for Some Than Others
Not All Bed Bug Bites Look The Same From Person to Person
Differences Between Bed Bug vs. Mosquito vs. Spider Bites
|Mosquito Bite||Bed Bug Bite||Spider Bite|
Raised welts that appears randomly on the body
Flat, red dots that may or may not be in groups of three.
Singular bite that can be red and itchy; sometimes has puncture marks from fangs
Bites qickly turn into itchy red welts
Bed bug bites do not start itching until later for hours or days
Spider bites' anticoagulant wears off slower, causing itchy red bumps or a rash to appear later
Bed Bug Bites on Thigh
What Does the CDC Say About Bug Bites?
Mosquito bites are far more dangerous than that of a bed bug because they transmit diseases such as malaria, West Nile Virus and Zika. Plus, they occasionally cause severe reactions in some people, so severe they need medical treatment. Resurgence of Mumps and Measles makes 2019 a scary time to have a rash that you can't identify.
You can call your local CDC to find out if these diseases are an issue where you live, and to find out how to check on your current immunities.
Bed bugs are not known to spread disease. Scientists thoroughly monitor bed bug epidemiology, and if they learn anything different, they will tell us. There was misinformation about the spread of Chagas. While scientists were researching it, some reporters jumped the gun. Bed bugs are very, very unlikely to make you sick (unless you have a severe allergic reaction.
There always seem to be rumors that bed bugs can spread the disease. But those claims often cite incomplete information, making the data inconsistent. More recently, the U.S. and Peru finished a joint study, and reported that bed bugs can not spread Chagas, or other illness.
If you were bit by a mosquito, and not a bed bug, the antigen uses during the bite is not nearly as long-lasting as that of bed bugs. That means that a mosquito bite will not continue to bother you the way a bed bug bite will. Bed bug bites start off numb, then itch, where a mosquito bites is likely to itch right away.
People with mosquito allergies have severe reactions to bites compared to those who are considered to be mosquito sensitive.
While bed bugs don't spread disease, they can cause financial disaster. Even though they are less dangerous, you must still discover everything you need to know to solve your problem.
Bug Bite Prevention
Due to the covid-19 virus many people are less inclined to travel. Travel is when you pick up bed bugs, as opposed to just being outside exposes you to mosquitoes. Theoretically you would be less likely to bring home bed bugs, but if you go outside you'd be just as likely to get bit by a mosquito.
Lots of people want to know if mosquitoes or bed bugs can carry covid-19.
Preventing bug bites is better than getting them. If you suspect you have a bed bug infestation, take action immediately. The longer you wait, the harder (and more expensive) getting rid of them becomes. If not then it may be time to look into alternatives.
It isn't uncommon for people to pick up bed bugs, spiders and roaches at hotels or while staying in other peoples' homes. To keep unwanted travelers from returning home with you, then inspect the bed and mattress where you plan to sleep.
If bitten by what you think is a bed bug while traveling, unpack your suitcase outside of your home. Carefully run laundry through a wash and hot dry cycle. Take steps to dis-infest your suitcase, too.
If you are staying in a hotel or vacation rental you should always check the room for bugs before you settle in.
But maybe you're not traveling, and you are seeing hives, bites or rashes. You are in need of other biting pest prevention methods.
The following are ways to prevent being bitten by flying and crawling insects and spiders:
- Use a good insect repellent that contains DEET on skin. Some good products are OFF!, Total Home Insect Repellent CVS brand, Avon Skin So Soft, Cutter and for little kids California Baby insect repellent.
- For clothes, tents, and other outdoor structures use a pesticide with permethrin in it.
- Clear spider webs, weeds, ant mounds, and standing water from outdoor areas.
- Try wearing light colors.
- When traveling or outdoors try wearing tightly woven underclothes to prevent bugs from getting tot he skin.
Poison Oak or Poison Ivy Rash vs. Bed Bugs
Bed bug and mosquito bites have very little in common with poison oak/ivy. Mosquito bites do not resemble poison oak or ivy. MedicineNet has some great pictures of the beginning of poison ivy and oak rashes.
All three types of rashes have the same reddish coloring and appear as a cluster of raised welts. However, bed bug and mosquito bites do not usually cause puss filled blisters the way that poisonous plants do.
A normal bed bug bite reaction will not have puss blisters or seep liquid, but a serious bed bug bite reaction that has been scratched might cause an open wound that looks like poison ivy.
Poison oak and ivy are creeping rashes that appear over time. If you rinse the affected area immediately after expose, then you may never get a rash.
Poison Oak vs. Bed Bugs Symptom Comparisons
|Poison Ivy/Oak Rash||Bed Bug Bites|
Comes in clustered groups
No, unless scratched and infected
Itchest at onset
No, unless infected
Is Poison Ivy and Oak Worse Than Bed Bugs?
An oozing bed bug rash is a sign of a serious allergic reaction that should be treated by a medical professional. Poison Oak and Poison Ivy cause fluid filled blisters on the norm.
Poison Ivy and Oak can spread from person to person, object to person, and other ways of contact, When a poison plant rash is oozing, it is still contagious. Even people with minor reactions will be in a serious state if it is spread to the eyes or respiratory tract. Bed Bugs bite people, but the rash caused by a bite isn't contagious.
Poison Plants leave a residue on skin and clothing. If you think you have poison oak, ivy, or sumac, then carefully wash all clothing items that may have come in contact with the surface, and don't touch your face.
Poison Ivy Rash
Mysterious Skin Condition. Not Bed Bug Bites.
Poison Oak Rash
Which Is Worse?
The answer depends on the type of spider. As noted, most spider bites are relatively harmless and will heal within a week or so, but if you notice any of the symptoms listed above, you'll want to see a doctor immediately.
Research With Caution: Take Extra Care With Children
The number of rashes in the world is endless. For example, the above picture is of an unknown dermatological condition that even the doctor couldn't decerne. That's why the more information you can gather, the more likely you will find the cause of the rash.
This rash almost looks like bed bug bites, but they were ruled out. This rash lasted for a very long time, and bed bugs bite would have vanished by then.
If you have an unidentified rash, especially one which returns, consider seeing a doctor. Children must always see a doctor for a mysterious rash or mysterious symptoms. They are more likely to get one of the five major rash diseases, which can be dangerous. They are also more susceptible to the flu, and the recent polio-like virus which the CDC confirmed in 22 states in 2018.
Identifying Spider Bites
Spiders are often referred to as poisonous when in reality they are venomous. Identifying spider bites is important if you live in an area with a venomous spider such as the Black Widow or Brown recluse.
Most people won't be bitten by the dangerous kind considering that there are more than 20,000 different types of spiders in the U.S. alone, and because each kind of spider bite looks different and causes a different reaction, it's hard to make sweeping generalizations about spider bites as a whole.
But still, it's important to recognize a spider bite when you see it. If a spider bites you, it usually won't cause a serious problem. You may see a visible reaction, it may hurt or itch, and you may even develop a blister, but that's the extent of it, and it usually disappears within a week or so.
Of course, it's much easier to diagnose and treat a spider bite if you saw the spider that bit you, but sometimes you may not even notice the bite until hours later. Look for things like pain, itching, burning, inflammation, redness, and skin damage. Sometimes you can see two puncture marks on the skin at the center of the reaction.
Look for the following spider bite symptoms:
- Skin damage or puncture marks
- Bump or group of bumps
If you have the following symptoms you may have been bitten by a venomous spider and should call your doctor:
- Severe headache
- Raised BP
- Inflamed lymph nodes
- Rapid Heart Beat
- Difficulty breathing
Spider bites take longer to heal than those of mosquitos and bed bugs. Spider bites may affect skin tissues in a more destructive manner. It's important to keep the bite clean to reduce the risk of infection. Unlike bed bugs, spiders are solitary creatures and usually only bite once, so if you see a cluster of bites, it was probably not a spider.
Mild spider bites are treated with over the counter creams. Venomous bites are treated with antivenins such as Anascorp, Anavip and Crofab.
A Spider Bite Looking a Little Like a Bed Bug Bite
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
Questions & Answers
Question: What are the signs of bed bug bites? What do I need to do to stop the itch?
Answer: Bed bug bites are clustered bites, usually in groups of three. The bites do not fill with pus under normal circumstances, only if there is some type of infection. They are small bites that start to itch as soon as the enzyme the bugs use to numb your skin wears off.
To stop the itch wash the bite, then use an anti-itch cream, oatmeal rub, baking soda paste, or aloe on the bite until itching subsides. The bites do not spread on their own. If new rashes show up, it means you have been bitten again.
Question: What do chiggers bites look like?
Answer: Chigggers are a type of grassland mite, but they are large enough to be seen by the human eye. They do not burrough under the skin. Instead, these tiny red bugs, do something similar to bed bugs.
Chiggars use a tubule to inject enzymes into the skin. Bed bugs do this to numb the area. Chiggars do it for a different reason, their saliva breaks down the skin cells so the little red pests can eat them. Yes, chiggars eat our skin.
Chiggar bites look like tiny red pimples, so small you almost can't see the injection mark left behind from the tubules. As you can imagine, as the enzyme decomposes a small area of your skin, it becomes very itchy, sometimes painful, and very red.
Question: If I think I’m allergic to bed bug bites what do I do first?
Answer: According to the American Academy of Dermatology serious symptoms of a bed bite allergy are: irregular heartbeat, breathing problems, fever, sickness, infection and anemia (rare). If you experience any serious symptoms of a bed bug bite, seek medical attention ASAP.
If you have less severe symptoms call your doctor and set up a consultation. While waiting for your appointment wash your bites with soap and water and use over the counter creams to treat the itching.
Question: Do oak mite bites spread?
Answer: Oak mite bites don't spread. Each clutser of rashes represents mites feeding on your skin. The thing about oak mites is that their bites are reported to appear anywhere from ten to sixteen hours after the bite.
Since you wouldn't know you were bitten for half a day, you may have more bites than you thought. This might make it seem like it's spreading.
Oak mites are too small to see, but they don't burrow beneath the skin. They only feed on skin. They don't plan to live on you long-term.
The problem with oak mite bites is that they are insanely itchy. Scratching them may lead to bacterial infection.
Question: What are these bites? They itch terribly. We were camping and fishing this weekend. Are they mosquito bites or bed bugs?
Answer: It is far more likely that itchy bug bites from a camping trip are from mosquitoes, spiders, and other bugs. If you stayed in a cabin, or someone else's RV there is a small chance you were exposed to bed bugs, but bed bugs like to live in civilization where the people with the blood are. I can't rule out bed bugs, but they are unlikely to be the cause.
Question: Why can't I donate plasma when I have bed bug bites?
Answer: The reason that you can't donate plasma when you have bed bug bites is because they are bug bites. While bed bugs are not known to spread diseases, there are lots of bugs that do. Technically other types of bites might also mean you can not donate plasma. The strictness of this rule depends on the plasma center.
There are many diseases caused by insects that can be transmitted through bug bites. Mosquitoes, ticks, and the kissing bug are all culprits of illnesses that can be spread through plasma. The medical professionals who work at plasma centers have no way to know what bites caused your marks, or whether or not they are infected.
When you donate plasma they do run tests to try to determine if you have any of the diseases bugs cause. If you have tested positive for any of them, you would be deferred. However, if you have many bug bites most plasma centers will defer you before you get that far.
Another factor is where you live. If the local CDC has information that there are positive test results for some types of insect cause sickness in your area, they may be more cautious when it comes to all bug bites, including bed bug.
Question: What kind of bite is 3 small bite marks that looks like a triangle?
Answer: I can't say for sure, but I can tell you that bed bug bites often come in groups of three. Bed bugs regularly make three bites during a single meal.
© 2012 Melody Collins
Macy Jackson on July 16, 2018:
Hello! Recently i've been getting these mosquito like bites on my arms and hands, they itch a lot and i seem to be getting them at night. But i know for a fact that they are not bed bugs because i've had them before and their bites are smaller than these. I have two on my forearm and they are quite large but arent red anymore because i got them a while ago, maybe three days ago. the recent ones are on my hands next to my wrist. its a medium sized red bump that also itches. And just to inform you before I wrote this post, I found a bug on my arm and it was a brown color and it was small and skinny and had a hard covering on it.I caught it and had it inbetween my fingers and it didnt really feel like a bug at all, just like a tiny little twig, but when i let it go it kind bounced? Im not sure how to explain it at all.
Rosemay James on June 05, 2018:
I think I have oak mite bites. I went for a walk on a walking trail. There were alot of trees and wild green bushes on both sides of the path. I woke up with both arms red with small bumps all over both arms. Not itchy. However I must have mosquito bites too, in my pelvic region. I have used everything from hydrocortizone, Caladryl, triamcinalone, and taking Benadryl orally. The redness is subsiding, butthere are still smal raised areas. I have not seen any evidence of bedbugs in my bedroom. How can I tell what I have?
Lyssa on May 30, 2018:
So, over the past few days some weird stuff has happened. It started a few days ago when I woke up with 20-30 bites on the back of my left thigh/lower butt. Itched like crazy, but we wrote them off as mosquito bites since it is summer and we live in the south. Then today, I was lying on my stomach in bed when I noticed the same thing on my other thigh. Lots of bites all on my thigh and lower butt. I have no sign of bites anywhere else. There's no sign of bed bugs in the house, and we do have fleas on our cats, however these bites don't look like flea bites and the flea problem is not too bad. Any idea of what these could be? They occur in one seems to be one large cluster on my thigh and go away after a day or so.
lana on January 27, 2018:
one day my friend texted me and said that she had bedbugs.i freaked out and looked all over my body for bites, then i finally found two on my arm, and then i remembered i stole a pillow from her older brothers room because i slept over two days ago.and so then i vacuumed and washed all my sheets blankets etc.so five days later (i went on a trip to San Diego) i come back all tired and fall asleep in my bed, the next morning i get TWO more bites on my other arm so i spend hours googling all this stuff about spiders,bed bugs,mosquito bites etc, so then i sleep on my couch for the last weak and a half and then i finally sleep in my bed after 15 bites ive had on my arms back hand EVERYWHERE so i sleep on my bed the next morning im good!!! i spent the whole day happy because i didnt get eaten alive, so last night i go to bed i wake up itching on my hand and im honestly shook about whats happening like how does this happen