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Whether or not you have pets in your home, fleas can be a big concern. One of the biggest problems with fleas is that they are often misidentified. The insect you’re seeing may actually be a flea, but it also might be a bed bug, a tick, or something else.
Flea season is typically at its highest during the summer. A good sign that your pet may have fleas is if they start to scratch themselves more incessantly and consistently in the same spot. However, a trip to the vet is recommended. Though sometimes difficult to spot, fleas are visible to the human eye in your pet's fur and will usually cause some redness on your pet’s skin.
In order to properly treat a flea problem, you need pest control experts to be able to identify the pest for you. Recognizing signs of fleas - such as small, dark specks (flea dirt), itchy bites, or seeing the fleas themselves - can help you determine if you have an infestation. If you think you have a flea infestation, contact Ehrlich today. One of our flea control specialists will come to your property and help put your mind at ease.
How to identify fleas
Fleas are small, blood-sucking parasites that live on animals and can infest your living spaces. Understanding what fleas look like can help you determine if these wingless insects are causing you or your pet discomfort.
Size and shape
Adult fleas are small, wingless insects with very narrow, flattened bodies, measuring about 2.5 mm (around 1/16”) in length—similar to the size of a sesame seed or the tip of a pen. They have six legs, and this flattened shape helps them move easily through fur or feathers, making it difficult to catch them with a flea comb or during grooming. Interestingly, fleas are at their largest during the larval stage, reaching up to 3/16” in length.
Color, hair, and facial features
Fleas are typically dark red to brownish-black. Their color can vary depending on whether they have recently fed—fleas may appear darker, closer to black, after a blood meal, while those without a recent meal are more reddish-brown. Their exoskeleton is hard and covered with backward-pointing hairs that help them navigate under a host's fur or hair and stay securely attached. Fleas primarily rely on their antennae and sense of smell for navigation, so their eyes, if present, are usually small and simple. As parasitic insects, fleas have extended mouthparts designed to pierce the skin and feed on their host’s blood.
Characteristics
Fleas are wingless insects, so they rely on crawling and jumping to move. Of their six legs, the four in front are shorter than the two long back legs, which enable them to jump as high as 7 inches—about 80 times their height—and up to 200 times their body length. Adult fleas are quick and can easily hide in your pet’s fur, but they are visible to the human eye when still. A single female flea can lay up to 40 eggs per day, contributing quickly to an infestation. While there are over 2,500 species and subspecies of fleas worldwide, the cat flea is one of the most common species encountered.
Cat fleas vs. Dog fleas
Although they are named cat fleas, these pests are not limited to felines. Cat fleas commonly infest a wide variety of mammals, including dogs, foxes, rabbits, and sometimes these fleas even bite humans. They are brownish-black to black, but after feeding on a blood meal, they swell and turn reddish-brown. With long hind legs, cat fleas can jump up to six inches in height, easily moving from one host to another.
Many dog owners may assume their pet has dog fleas, but in reality, most cases involve cat fleas. While both types of fleas are similar in appearance, the differences between them are best observed under a microscope. Under magnification, the heads of cat and dog fleas have distinct shapes: the head of a cat flea is about twice as long as it is wide, giving it a more elongated appearance. In contrast, dog fleas have a more rounded head with a shorter length-to-width ratio. Additionally, the bristles (or setae) on the legs and body are arranged differently, providing further distinction under close examination.
Understanding the difference between cat and dog fleas is important for effective flea treatment. Cat fleas are more common in the United States and have slightly different resistance profiles to certain treatments compared to dog fleas. Knowing which flea species is present can guide veterinarians and flea exterminators in choosing the most effective control methods, ensuring that treatments are better tailored to target the specific flea population on your pet or in your home.
While both types of fleas can transmit diseases and cause intense itching and discomfort, treating cat fleas may require a stronger or more frequent approach, given their resilience and prevalence in various environments.
What do flea eggs look like?
Flea eggs are very small, less than .019”. They are round or oval in shape and white in color. Flea eggs are unlike any other parasites’ eggs in that they are not sticky. Therefore, once they are laid, often directly on the host, they usually fall to the ground, contaminating the environment.
In fur, flea eggs can get confused with dandruff. The major difference between these two is that dandruff is flat, unsymmetrical, and will stick to your pet's fur, whereas flea eggs are that round, oval shape and will likely move around since they are not sticky.
Flea eggs hatch into larvae that look much more like a worm than a flea. In this stage, fleas have no legs or eyes. Flea larva is white but translucent. As it progresses through three molts to the pupal stage, it will gradually get darker in color.
The flea life cycle and how their appearance changes
Fleas have four life cycles: egg, larva, pupa, and adult. Each stage looks quite different, and understanding this cycle can help control an infestation effectively.
1. Egg stage
The flea life cycle begins with the egg. Female fleas lay up to 40 eggs per day after a blood meal, usually on the host. These eggs fall off into the environment, allowing them to spread around your home, particularly in areas your pet frequently visits. Flea eggs are tiny and white, making them difficult to see.
2. Larval stage
After hatching, flea larvae emerge. They are about 2-5 mm long, worm-like, and white, though they can appear slightly translucent. Unlike adult fleas, larvae do not suck blood; instead, they feed on organic debris, including flea dirt (flea feces). Flea larvae are usually found in dark, damp areas where your pet rests, such as carpets, upholstery, or bedding.
3. Pupal stage
In the pupal stage, flea larvae spin a cocoon, becoming a pupa. This provides a protective covering, allowing them to survive for long periods in adverse conditions. Fleas can remain in the pupal stage for days, weeks, or even months until environmental conditions are ideal for emergence.
4. Adult stage
The adult flea is the final stage, emerging from its cocoon when it senses vibrations, heat, or carbon dioxide. Adult fleas seek a blood meal soon after emergence. Wingless and small, they rely on their powerful jumping ability to move between hosts. Once on a host, they feed and mate, with female fleas beginning the egg-laying process shortly after their first blood meal, thus continuing the flea life cycle.
Other bugs that look like fleas
Often mistaken for fleas are those pesky pests biting you at the beach. Despite what you may have been told, sand fleas are actually not fleas. In fact, they aren’t even insects. Are there different kinds of fleas? Yes, but sand fleas are not one of them. The term “sand flea” is often incorrectly used to describe various insects such as regular fleas, gnats, midges, and flies. This misidentification generally occurs because all of these pests can leave behind an itchy bite.
These tiny crustaceans are usually tan or grey with long front antennae. Like fleas, their exoskeletons are hard, but they can grow up to 1½” inches in length and have visible eyes. They are most commonly found at the beach and typically come out at night to find food.
Ehrlich can identify fleas
Fleas are an obnoxious pest for humans and pets alike, so don’t let them stick around. No matter the type of flea that is giving you trouble, Ehrlich can help. Your specialist will consider the areas where your pets spend the most time and will treat the areas where larvae may be found and where fleas like to hide. Contact us today for a flea inspection or call 800-837-5520.
Frequently asked questions
What can be mistaken for fleas?
Several tiny insects can be mistaken for fleas, including bed bugs, ticks, carpet beetles, and even certain species of mites. Bed bugs and carpet beetles, in particular, are often confused with fleas due to their similar size and shape. However, fleas are typically smaller, wingless, and have long, powerful hind legs for jumping. Ticks are also commonly mistaken for fleas, but ticks are usually rounder and don’t jump like fleas do.
What do indoor fleas look like?
Indoor fleas look very similar to outdoor fleas—small, dark brown, or black, with flattened bodies that are about 2.5 mm long (the size of a sesame seed). Their bodies are also covered in tiny hairs that help them move through fur and feathers. After feeding, fleas may appear plumper and reddish-brown. You may find fleas around your pet’s bedding, carpeting, or upholstery, especially if an infestation has started inside.
Are fleas visible to the human eye?
Yes, adult fleas are visible to the human eye, though they are very small. At around 2.5 mm, fleas can be seen crawling or jumping in your pet’s fur, floors, or even skin if they come into contact with you.
How can I tell if I have fleas?
Signs of a flea infestation include noticing small, dark specks (flea dirt) on your pet or in areas where your pet spends time, seeing fleas jumping, or observing your pet scratching or biting themselves more frequently than usual. You can also use a flea comb on your pet to help detect fleas and flea dirt. If you’re unsure, consult a pest control professional who can help confirm their presence and get rid of fleas using a suitable flea treatment plan.
Can you feel fleas crawling on you?
While fleas are very small, some people do report feeling them move or bite, especially on sensitive areas of the skin. Fleas move quickly and may jump onto exposed skin, where they can cause a tickling or itchy sensation. Flea bites are usually noticeable, as they cause small, red, itchy spots. However, because they are so tiny, fleas may sometimes crawl unnoticed, especially if they are in pet bedding or carpets.