Home Bed Bugs Flea Bites vs Bed Bug Bites + Differences & Pictures

Flea Bites vs Bed Bug Bites + Differences & Pictures

Telling the difference between a bed bug bite and a flea bite may be quite a challenge especially if you’ve little or zero experience on these insects. Knowing which bite is from what bug is key if you want to find the appropriate treatment. Read on to learn the differences and similarities in terms of symptoms, size, pictures and cures

An overview of Fleas & Bed Bugs

Fleas are a common name given to Ctenocephalides fellis (Cat flea), Pulex irritans (Human flea) and Xenopsylla cheopis (Rat flea) and are parasites that feed on blood.
Picture of a flea
Flea photo
They normally prefer human beings as their host but are also dominant in household pets such as cats, dogs, rodents and opossums. Predominance is observed in cats in which they are known as cat fleas. It is the cat flea that infests both cats and dogs then eventually humans. Bed bugs are of the genus Cimex and three species implicated in the infestation of houses; Cimex lecturalis, Cimex adjuctus and Cimex hemipterus.
photo of a bed bug
Bed bug
Bed bugs  do not live on bodies of their hosts and are only there momentarily to feast on a blood meal. Like fleas, they can also be found in clothing such as shoes and bedding but bed bugs can also be found in hinges, walls and furniture. Both of these insects do not fly and while this is true for both, fleas seem to try to do so. They have been known to jump from one place to another to as high as 8” vertically. This is typically 150 times their height. Bed bugs have to crawl to get to their destinations. One interesting fact is that one flea is able to lay number of eggs in a week commensurate to those that can be laid by a bed bug in its life time i.e. about 200 eggs. While it is not entirely known whether bed bugs can act as vectors of pathogens and cause disease in its hosts, fleas are known carriers of the bubonic plague, cat-scratch fever and murine typhus through infecting rodents such as rats (Gary R. Mullen; Lance A. Durden., 2017). All these are well discussed in the following sections.

Flea bites vs bed bug bites -How to tell the Difference


The appearance of either bites may be somewhat similar but there sure is some difference between them. The characteristics that follow the bite of a flea are as follows:
  1. If you have seen a mosquito bite, then that’s how a flea bite looks like. These bites are inflamed and have a raised center.
  2. The bite is more of a simple dot that is marked with a darker red at the center.
  3. When fleas bite, they do so in a random fashion on the body. This means that there is no particular pattern associated with how the bits are organized. Just like mosquito bites, flea bites may also appear in clusters which again do not define any pattern.
Bed bug bites bear the following characteristics in appearance:
  1. Bites that are rather flat with not characteristic center to it. The area is inflamed and therefore red in color. However, the bites may just bear the skin color of the individual and are rarely commonly red especially in dark complexioned skins. Welts can be closely associated with how a bed bug bite looks like.
  2. There is a pattern to its bites. It appears as if the bed bug crawls while biting in its path. The bites appear as small inflammations in a straight line. Most commonly about 4-6 bites in a line.
  3. The appearance is relatively gradual as compared to flea bites.


The size of bed bug bites are about 4-5 mm long and 1.5-3 mm wide while those of fleas are about 1.5-3.3 mm long.

Disease Transmission

Bed bugs have not been associated with any disease of pathogen transmission as has in the case with fleas. The three types of fleas have potential for different disease transmission and therefore pose a risk to humans in a variety of ways. However, this is not to say that every flea bite will transmit a disease to humans. Discomfort is an avoidable effect of a flea bite but you may get down with a fever after such bites. This is the best time to go see a physician. According to CDC (Center for Diease Control) Known diseases that are associated with fleas include :

Murine typhus/endemic typhus

This is one of the group of typhus conditions associated with a fever, headache and a rash. These symptoms are known to start of one or two weeks after you have been exposed to the bacterium responsible. Fleas among its counterparts such as lice and chiggers are responsible for the three typhus conditions. The flea responsible is the Xenopsylla cheopis usually found on rats and other rodents. Do not confuse this with epidemic typhus that is spread by lice. If you have been infected with Rickettsia typhi and Rickettsia felis from fleas, you will realize symptoms such as a fever, muscle and joint pain and nausea and vomiting. However, it is hard to realize that the connection would be to a bite about one or two weeks ago.

Cat-scratch fever

When fleas carry a bacterium known as Bartonella henselae, you can get this diseae. Mostly affects children when they are bitten or scratched by a cat that is infected by the bacterium. It also presents with lymphademopathy about one or three weeks after being bitten.

Bubonic plague

This disease is caused by a bacterium known as Yersinia pestis that is at times borne in its vector, the flea, Xenopsylla cheopis. This type of flea is found in rodents such as rats as its host. It is from the rats that the fleas acquire the bacterium which eventually is passed to humans during a blood meal. he proboscis of the flea injects the saliva with its content, Y. pestis which then travels to the lymphatic ducts. Bubonic plague is just one of a series of diseases that are associated with the bacterium as depending on its mode and level of spread, may complicated into septicemic or pneumonic plague. To identify bubonic plague, swellings known as buboes appear in areas where there are lymph nodes such as the armpits, groin, upper femoral (thigh) and the neck region and is followed by a gangrene and necrosis of the nose, mouth, fingers and toes. You will get chills, muscle pains, elevated body temperature and general body weakness (Bennett’s Principles and Practice of Infectious Diseases E-Book).


You will definitely react in the same way when you are bitten by a flea or a bed bug. Both of the bites are itchy and inflamed. However, there are degrees to which the two reactions occur with the two bites. For instance, flea bites are known to be very itchy. Extensive itch and scratching as a reflex reaction to it is therefore common and at times wounds follow. The itch by a bed bug bite may be less itchy and when you have rubbed the area gently, the inflammations fade away in minutes. This may not be the case with flea bites. When flea bites are scratched, there is a potential for wounding and therefore infections. This is rare with bed bug bites and when they have to complicate, then they will turn into blisters.


You can be able to identify a bed bug or flea bite based on the appearance and if you are lucky, site the breaching insect. In order to do a differential diagnosis do the following:
  1. Observe the pattern of the bites
  2. Observe for any dark spots on the bites
  3. Check for any other locations on your body
  4. If you have a pet, then you can raise your eyebrows for the possibility of a flea.
  5. To calm the itch, rub gently and observe for any changes
  6. According to the characteristics given in the previous sections, if not a bed bug, then monitor yourself for any symptoms.
If you have made a thorough observation of the bumps and are still not able to tell, the ask yourself the following questions:
  1. If you have been out lately and a lot.
  2. If you have seen your pets outdoor much and signs of discomfort such as scratching
  3. If you can see some smudges on your sheets.

What and where they bite

Bed bug bite you when you are asleep or seated on your bed or other household furniture. Fleas are mostly on your pets, either a cat or a dog. While bed bugs normally bite anywhere on your body, fleas are rampant in biting lower extremities such as the legs and ankles.

Getting rid

In order to get rid of the bed bug or flea bites, check out the following section on treatment and prevention.


Bed bug bites are commonly self-limiting and you can easily reduce the inflammation by rubbing hard on the streaked areas without scratching. Scratching worsens the inflammations. If the itch is getting worse and unbearable, then you can get an over-the-counter anti-pruritic and anti-histamine. Some of the options that you can look at include a corticosteroid cream such as hydrocortisone or betamethasone. Remember, that you can also run some cold water or apply some ice-pack over the area. Just make sure that you avoid host water as this may exacerbate the itchiness. Other oral over-the-counter medications include Chlopheniramine or cetirizine which are anti-histamines. All these interventions can be used to relieve the itch and inflammation associated with both a flea and bed bug bite. Other home remedies that can be used include the use of peppermint, lavender oils, by applying on the area to relieve the itch.


You can prevent being bitten by a flea or a bed bug in the following ways: Flea bites
  1. Cleanliness and hygiene can never be over-estimated. Vacuum you carpets and pets regularly. The carpets and pets could harbor the fleas.
  2. Make sure that you clear your lawn of bushes if you have pets that spend time outside.
  3. Wash your cats and dogs with soap and water. Brush them often.
  4. Take your pets to the veterinary often for an examination.
Bed bugs
  1. If you have bed bugs, then contact the professional pest service to treat your house.
  2. Use interceptors on the feet of your bed so that you can monitor any presence of bed bugs.
  3. Infested items such as mattresses should be wrapped and disposed of.

Flea bites vs bed bug bites on humans Pictures

Below are pictures of bed bugs and flea bites on leg and hand of humans
flea bite picture
Flea bite
Bed bug bite picture hand
Bed bug bite


Flea and bed bug bites are both itchy, cause inflammations, may turn red and can be treated with the same treatment approaches. This material has already debunked most of the previously perceived similarities to inform you on the differences between the two. Further Reading