How to Test for Fleas – Identifying the Pest and What to Do With it

Fleas can infest any home, regardless of how clean it is. Still, the chances of an infestation increase if you have furry pets. And since fleas love their thick coats and warm bodies, the infestation can grow in large proportions if not identified right away. For this post, we will discuss how to test for fleas, what you can do about it, and how you can prevent future re-infestations.

Characteristics of fleas

Fleas can be difficult to determine from ticks and other insects. Since both ticks and fleas infest dogs, it can be challenging to distinguish which is which.

➡️Life cycle

Fleas undergo four stages within their lifespan: egg, larvae, pupae, and adulthood.

how to test for fleas

*Egg. Flea eggs are small and have a whitish color. Once the fleas have laid eggs on your pet or any surface, it will fall off anywhere in your home. This will fuel the spread of the infestation.

*Larvae. Within 2 to 10 days, the flea egg will hatch and become larvae. These larvae will feed on the feces of adult fleas as well as dead larvae.

These tiny and vulnerable larvae will hide within the crevices of your home, including your carpet, furniture, headboards, and more. This phase will last for up to 15 days or until the larvae reach the pupae stage.

*Pupae. In this stage, the larvae will become cocoons to reach adulthood. Flea larvae are so sneaky that they can hide in the most hard-to-reach areas of your home. It’s the reason why flea pupae can survive DIY extermination methods.

*Adult. After 1 to 3 weeks, the pupae will hatch and give birth to adult fleas. Usually, the adult fleas will come out of the cocoon during the most favorable condition. They will feed on the nearest host and lay eggs. The process goes on and on until the flea population becomes massive.

From then on, the adult flea will feed on its host for more or less 100 days.


Fleas are usually 3 mm long. It has a reddish or brownish color as well as a flat body that becomes inflated upon feeding on dogs, cats, or humans.

In the naked eye, fleas are elongated insects. Sometimes, it would be mistaken with ticks. However, the latter has a rounded body and can grow for up to 1 cm. They look like tiny spiders, but unlike fleas, they jump.


Fleas feed on the blood of humans and furry animals and they will do so every 5 minutes to sustain their diet. Usually, their population and feeding habits peak during the fall and summer seasons due to the hotter temperatures.

Overall, fleas will suck blood equivalent to 15 times of their body size. This blood-sucking activity will last for up to 3 months.

This diet is necessary for them to sustain their reproduction. An adult female flea will lay up to 50 eggs a day. It’s the same reason why a flea infestation spreads fast in just a matter of weeks.


Fleas crawl or jump to reach a host. They can jump horizontally for up to 13 inches and 7 inches vertically.

This pest harbor on hairy animals – the same reason why most species can’t survive on human skin.

Aside from dogs and cats, fleas also harbor in possums, mice, rats, and other wild animals. Take note that there’s a flea species, Pulex irritans, which harbor on the human body.

In this webinar, Dr. Nancy Hinkle from the University of Georgia tells us more about fleas, various species, and how it affects your household and pets.

Types of fleas

There are six most common flea species out of the 2,000 ever recorded:

➡️Human fleas (Pulex irritans)

Human fleas or Pulex irritans can grow between 2 mm to 3.5 mm. This species has a small body and a long abdomen. Also, they have three pairs of legs and five antennae segments.

Although called as human fleas, this species can also feed on animals. Also, this species thrive in hot areas and seasons.

You should also know that human fleas will become widespread if you have pets.

➡️Dog fleas (Ctenocephalides canis)

Dog fleas are the most common species found in homes, mostly because its main hosts are canines.  Take note that dog fleas have stronger teeth than human fleas. This is because they are equipped to dig deep into the skin of the host to suck blood.

Like human fleas, dog fleas grow between 2 mm to 3.5 mm. Also, they have eight pairs of teeth on each of their six legs.

When it infests dogs, it will usually bite on the tail, head, and neck area. Dogs infested with this species will itch and scratch incessantly. Again, it can bite humans and infest other pets.

➡️Cat fleas (Ctenocephalides felis)

Cat fleas infest cats, but they can also transfer to dogs or even bite humans. These species are the strongest when it comes to jumping. They also have three pairs of legs with 8 to 10 teeth on each pair.

Take note that cat fleas will die within hours if deprived of a host. Still, some may last for days, depending on the environment.

➡️Bird fleas (Ceratophyllus gallinae)

This species is known to attack birds, poultry, and even humans. Bird fleas also have strong teeth that can pierce the skin.

Take note that bird fleas like to stay within the nest of their hosts. If they can’t find a bird host, they will transfer to humans in order to survive.

➡️Sand flea (Tunga penetrans)

Sand fleas are quite different than the other species mentioned above. They are also known as chigoe and can be seen in warm and near-water areas. They are also seen on beach areas, thus their name.

Aside from that, sand fleas are also the smallest species since it only grows to a maximum of 1 mm. When placed under the microscope, this species looks like a little shrimp or crab.

If you went to the beach and felt an itchy feeling that lingers for days, it’s best to seek the opinion of a dermatologist. Sand fleas can lay eggs beneath your skin, making you the host of the infestation.

➡️Sticktight fleas (Echidnophaga gallinacean)

The last of the six most common species is Sticktight fleas. These fleas will stick to birds, but it can also feed on horses, humans, and more hosts.

The reason why it’s called sticktight is due to the fact that it sticks well on the surface of the hosts’ skin. They attach their heads beneath the skin, making it difficult to remove by combing alone.

Take note that sticktight fleas can lead to complications like anemia if not treated right away.

Risk of fleas

The dangers of fleas manifest primarily on household pets. Since the fleas can harbor on their fur, the biting would be constant, which can lead to complications and dermatological problems.

If the fleas happen to contain tapeworm, it could also infect the pet when the fleas are ingested during grooming.

Pets will experience hair loss, skin infection, and irritation. In the worst cases, small pets will develop anemia and life-threatening conditions.

The challenge here, especially with cats, is that they groom too efficiently. This will lead the fleas to move fast. With this, spotting the infestation becomes more difficult.

You should also be careful since most flea species feed on humans. Aside from the itchy welts it may bring, fleas are also hosts of communicable diseases.

Take note that sand fleas or chigoes are the worst. There was a recorded case when the chigoe bites resulted in secondary infections like gangrene and even amputation of the fingers or toes.

Also, fleas can impact your mental health. The avoidance of family and friends due to the infestation will add up to the burden of the fleas.

Common signs of flea presence

If you suspect that your home is harboring fleas, you can confirm it by looking for the following signs:

➡️Flea dirt

Flea dirt or feces are dark in color. Usually, you’ll find it on the fur of your pet, characterized as coarse black specks. Sometimes, fresh flea dirt will have a reddish color on it.

You can try wiping your floor with a clean, white towel to see if you’ll catch this dirt.

➡️Flea eggs

Flea eggs are very tiny and have an off-white color. It actually looks like a white speck that you can barely see if it gets stuck on the carpet, sheets, or couch.

Most of the flea eggs will be 2.5 mm long. If you see dark specks mixed with white specks on your pets’ fur, it could be a sign that the fleas are reproducing.

However, you should avoid mistaking flea eggs from dandruff. Flea eggs aren’t sticky and have rounded edges. Meanwhile, dandruff is irregularly shaped and comes in thin, paper-like consistency.

➡️Flea bites

If you see bites on your ankles or your pet has red scabs, you should check for flea infestation right away. These are tell-tale signs and just the tip of the iceberg. The fact that the fleas are already feeding on humans is a symptom of a widespread infestation.

How to test for fleas at home

When checking for fleas at home, you can use the ‘Sock Test’. You just have to wear a clean pair of white socks long enough to reach your calves. After that, walk around your home, ensuring that you spend some time on carpets and rugs.

You can rub your feet together to produce heat since fleas are attracted to it. After a few minutes, check your socks for brown and black specks. Also, there would be some fleas that would hitchhike to feed on your blood.

Some of the must-checks on how to test for fleas are your pets’ bedding, your carpets and rugs, and your upholstered furniture.

How to test for fleas on pets

Next, you should inspect your pets if you have any. Most of the time, your furry friends are the main hosts of the insects. Dogs and cats that scratch too much and shake their heads are probably infested with fleas. You can confirm this by combing your pet and spotting the fleas as they feed.

Check from head to tail. Also, look on the common hideouts of fleas on your pet, including its tail, neck area, groin, and skin folds. Breeds like Shar-Pei, Pugs, and Bulldogs should be examined well since their skinfolds can harbor a large population of fleas.

If your pets happen to have fleas, you can use the treatments that Dr. Courtney Campbell discusses in this video:

How to test for fleas on your yard

You should know that fleas thrive in your yard. Your pets will likely pick up the insects outdoors.

Fleas love staying on shady and moist areas outdoors. These could be the pile of wet leaves, under the bushes, pool decks, and around trees. Also, it will help to check where your pet loves to stay outdoors.

Again, you can try the Sock Test here. Rub your feet and let it stay on a specific spot. Using a flashlight, check for any crawling fleas.

How to prevent future infestations

Future infestations could only be avoided if you target the root cause of the problem. Also, it will make a big difference if you groom your pets regularly and check their fur.

Experts recommend that you perform flea treatments all year round. It’s a proactive approach to keep the fleas at bay from your home, your pets, and your skin.

You can also perform the following preventive measures:

*Vacuum your home regularly. Vacuuming is an excellent way to suck out flea eggs on carpets, rugs, and tiny crevices. Take more time on the areas where your pets love to stay.

*Wash pet bedding periodically. Washing your dog or cat’s bedding in the hottest temperature possible is a guaranteed way to kill any fleas. Also, you should wash your pillowcases, sheets, and other linens regularly.

*Aerate your carpets and rugs. At least once every two weeks, hung your rugs and carpets under direct sunlight. This will help remove the fleas and kill the eggs.

Final words

Knowing how to test for fleas and identify the pest is the first step to fix an infestation. Once you confirmed the presence of the insects, you can call a flea expert to perform the extermination.