We don’t know you. But we know that if you’re asking what do fleas look like, it’s not for curiosity’s sake. Because nobody looks at pictures of fleas for fun.
The chances are that you’ve found a small, biting pest in your home that is slowly robbing you of your sleep and sanity.
So let’s nip that in the bud. Fleas may be small but they aren’t difficult to identify, especially if you know what to look for. By the end of this article, you’ll be an expert at identifying fleas as well as the tell tale signs of a flea infestation.
And if that isn’t a great party trick, we don’t know what is
What Do Fleas Look Like?
If you grew up in the 90s – and don’t have much first-hand experience with real life fleas – the first mental picture that comes to mind may be of a little cartoon flea. Such as the lovable A. Flea from the Looney Tunes, with his funny songs and chipper attitude.
This article is going to demolish that mental imagery of fleas.
And that is a good thing. Because to fight the battle against fleas – and win! – you’ll first need to see them up close in all their disgusting glory.
Why, you ask? Fleas are revolting up close, you protest.
Well, you’ll have to know exactly what they look like and how they operate in order to better fight this bloodsucking pest.
And not just full-grown adult fleas. It’s actually fleas in the other stages of the life cycle that make them such a difficult pest to get rid of.
So strap in and steady your stomach because it’s going to be a deep dive.
Flea Life Cycle Pictures
Most pictures of fleas you’ll find online are of the full-grown, adult flea. That’s because it is when they are adults that fleas become the annoying, blood-sucking nuisance they are.
But despite the fact that adult fleas get the most attention, they are actually the least important in a flea infestation. In fact, any pest control expert worth your time will insist that if you don’t kill the flea babies, you’ll never be rid of fleas.
So let’s learn more about the stages of development fleas must go through before they reach maturity.
There are four stages to a flea’s lifecycle:
- Eggs. Fleas begin their lives as eggs that female fleas lay prolifically, mostly on their hosts’ bodies. The eggs aren’t sticky, though, so they tend to get scattered around the home.
- Larvae. After a short period of time – just 1 to 10 days, the eggs become flea larvae. They don’t bite or feed on blood at this time. Instead, their main diet is adult flea feces and dead flea larvae.
- Pupae. The next stage in a flea’s life cycle is when the larvae creates a pupa, from which it can mature into an adult flea.
- Adults. The final stage in a flea’s life cycle is when it emerges from its pupa as a young, blood-sucking adult flea.
It is really important that you understand what fleas look like and do before they become full-fledged, blood-sucking adult fleas precisely because it is then that you have the best opportunity to nip the vicious flea cycle in the bud.
To do so, you’ll first need to know what they look like.
What Do Flea Eggs Look Like?
Adult fleas are tiny. So that gives you an idea of how big flea eggs can be.
The best way to think of a flea egg is visualize a grain of salt. Yup, that’s how small these eggs are – microscopic, at just 0.5 millimeters long and about 0.25 millimeters wide.
Flea eggs are notoriously difficult to see because they are smaller than a single grain of sand. And yet, flea eggs are of major importance for three reasons.
First. There are a lot of them.
Female fleas lay anywhere between 20 to 50 eggs per day.
That may not sound like much but it adds up – a female flea can lay over 2,000 eggs within the course of her lifetime.
Second. Eggs aren’t sticky. Female fleas prefer to lay their eggs on their hosts’ bodies but because the eggs don’t stick, they’ll easily roll right off Fido and onto your couch, bed, or carpets – pretty much anywhere your pets may roam.
Third. Many pesticides and devices that kill adult fleas don’t work for the eggs.
This is precisely why getting rid of fleas permanently requires a multi-pronged solution.
Flea babies are resistant to the pesticides that work to kill adult fleas so you’ll have to use varied methods to get rid of fleas in all life stages.
Flea babies, you say? Let’s move on to the next stage in the lifecycle of fleas.
What Do Flea Larvae Look Like?
Fleas don’t remain eggs for long. Flea eggs hatch in just one to ten days, depending on the temperature and humidity of their environment.
Below, you can see a very close-up picture of a flea larva hatching from its egg.
If your home is optimal for fleas, say, between 70-85°F with around 70 percent humidity, fleas will hatch from their eggs in just a few days and enter their next stage in development.
This next stage after fleas hatch from their eggs but before fleas mature into the full-grown, blood-sucking pests we all know and hate is the larvae stage and it marks the second phase in the flea life cycle.
Flea larvae are able to move about but in this stage, they are mostly hapless little babes that are content to lie about and feed on adult flea excrement rather than you or your pets’ blood.
What was that, you ask? Flea excrement? Yup. As abominable as it is, you can’t put anything past these fleas. Flea larvae need the blood content that’s in adult flea feces in order to grow and mature.
Of course, flea feces isn’t all that they eat. They’ll also happily much on shed skin cells from people and animals as well as dead flea larvae.
And if you thought that flea eggs were near impossible to spot, you’ll have an even trickier time coming across flea larvae. You see, flea larvae don’t like the light and will crawl away to avoid it, seeking dark and warm places like deep into carpets and under skirting boards.
And there they stay until they’re ready for the next stage in their development.
After molting twice in their flea larvae stage and spinning their protective pupal cocoon, flea larvae fold themselves in half and become flea pupae.
Above is a picture of flea larvae molts, amongst eggs and flea feces. We warned you this article wasn’t going to be pretty.
What Does Flea Pupae Look Like?
Flea pupae are tricky to describe. In short, flea pupae are about the same size and appearance as adult fleas. But – and this is a big but – you won’t really be able to recognize them as such.
That’s because flea pupae start off as a creamish-white, then transition into a yellowish color and finally darken into the brownish color that characterizes adult fleas. But those color changes only happen to the developing flea within the cocoon. The cocoon itself remains colorless.
To add to the trickiness, flea pupae are also extremely sticky, which means that the dust and debris in the surroundings, like hair and carpet fibers, will stick to the cocoon, creating a sort of camouflage and helping them further evade detection.
Now for the truly bad news. Not only are flea pupae very difficult to spot, they are also very difficult to kill. While they are hidden inside the impenetrable protection of the pupal cocoon, flea pupae cannot be killed by any insecticides you throw at them.
Oh wait, it gets worse. When weather conditions are optimal, flea pupae catch hatch after just a couple days but if conditions are bad, fleas can survive in their pupal stage for well over a hundred days.
So if you happen to miss some flea pupae during your flea treatment, you may just be surprised with another flea infestation further down the road.
And this is why we highly recommend the humble vacuum as one of the best flea fighters you have access to.
Not only will the vacuum allow you to quickly get rid of adult fleas, flea eggs, and the flea feces that flea larvae feed on, but the vibration from the vacuum can stimulate the flea pupae to hatch.
Once the pupae have hatched into adult fleas, you can finally kill them.
And that brings us to the final stage in the fleas’ life cycle: the adult flea.
What Do Fleas Look Like to the Human Eye?
Let’s start with the basic question: what do fleas look like?
The simplest answer is that adult fleas are small, dark, and wingless parasites with hard shells and six legs that are thin and oval-shaped. But you won’t see them that way unless you have a microscope because to the human eye, fleas are very, very small.
Fleas are visible to the human eye, even without a microscope. The thing is, though, they are just barely visible.
By that, we mean that you can see them but you most likely won’t be able to make out all their individual features and parts. Like so…
And that’s because even when they’re fully grown, fleas only measure around 1 to 3 millimeters in size. That means you can line up 8 fleas side by side on a ruler and they’d barely take up an inch! That’s some serious smallness.
Below, you can see how an adult flea looks on a man’s thumbnail. Visible, yes, but very tiny.
Below is another picture that shows how small a flea is – it’s a little dead flea on a 10¢ Canadian coin.
What also doesn’t help is that when viewed from the top, fleas have rather thin bodies, like the below picture of an adult cat flea.
So to the naked human eye, fleas will look like little black dots moving around.
And oh, do they move. In fact, fleas have been seen to jump as far as 13 inches, which is about 200 times their own body length!
That ability to jump is important because it can help you confirm if it is, in fact, fleas you’re dealing with.
But none of those other pests can jump like fleas can. So if you have a tiny, biting insect that jumps like an Olympian, it’s most likely fleas.
Being able to identify flea behaviors is important because as you already know, fleas are small and can be difficult to identify on looks alone. Which is why you’ll want to be on the lookout for other clues that you have fleas. Bugs that jump is one clue. Another? Flea dirt.
What Does Flea Dirt Look Like?
If you have fleas, you’ve probably seen flea dirt before without even knowing it. You may have found what looks like specks of dirt in your pet’s hair, like below.
We’ve got some bad news for you. Flea dirt may look like little specks of dirt but it is actually the feces of adult fleas.
If you look closely, you’ll find that it’s more reddish-black than pure black because it contains the not-fully-digested blood meal that is the adult fleas’ main diet.
Of course, you won’t just find flea dirt in your pet’s fur. You’re likely to come across it scattered around your home, mostly in places where your pets like to roam around and spend their time.
Want to make sure it is indeed flea dirt you’re looking at and not just specks of dirt you or your pet dragged in? Wet it with a spray or dab some onto a wet paper towel. It is “bleeds” – you know that it’s got some blood in it. It’s flea dirt.
Flea dirt, as awful as it is, can be useful to clue you in to the fact that fleas are present in your home. The sooner you know, the sooner you can begin the war, right?
Another clue? You guessed it. Flea bites. Let’s find out what those look like on humans and animals.
What Do Flea Bites Look Like on Humans?
A bite is a bite, right? Not quite. Many people get confused about the difference between, say, a bed bug bite vs a flea bite. But while differentiating pest bites isn’t an exact science, there are some ways to tell the difference.
For starters, bed bugs are super sneaky. So sneaky that they’ll wait until the darkest hours of the night, the time you’re most likely to be in deep sleep, to feed on you. They even inject you with a mild anesthetic so that you won’t even feel their little bed bug bite until long after they’ve absconded with their blood meal.
Fleas, on the other hand, are neither sneaky nor subtle.
When they’re hungry, they’ll jump up and take the blood. And they won’t wait until you’re sleeping, either. So flea bites can and will show up anytime, anywhere.
With flea bites, it’s likely that you’ll feel the bites right away and they’ll be very itchy.
Another simple way to distinguish between bed bug bites vs flea bites is that bed bugs tend to bite in clusters, typically in areas of exposed skin. Fleas, on the other hand, are more haphazard and will simply take the blood from wherever they can.
Usually, they’ll have to jump up to bite you so a tell-tale clue is if you have bites mostly focused around your feet, ankles and lower legs.
Looks wise, flea bites are usually small, discolored bumps. They may have a dark red center where the fleas sucked the blood and a discolored ring – aka halo – around the bite.
But determining whether you have fleas from bites alone is not an exact science since flea bites can look different from person to person, depending on both severity of the bites and your body’s reaction to them.
As you can see above, flea bites on humans can even blister or swell. So don’t rely too much on the appearance of bites as a confirmation of fleas. Look for the other signs we’ve depicted above as well – aka flea dirt – as well as how your pet behaves and looks.
What Do Flea Bites Look Like on Dogs and Cats?
Because our furry friends tend to be covered in fur, you may not see the flea bites on their little bodies until you start to go looking.
But you will most definitely notice other signs of fleas, such as excessive scratching and restlessness.
And when you do, you’ll want to go looking. But what do flea bites look like on dogs or cats? Here are some pictures.
Above, you can see some subtle flea bites on a dog’s belly. Below, you can see that flea bites on dogs can also be a lot more pronounced and hard to miss.
If you also have flea bites, you know exactly how itchy and miserable they can be. So when you find that your pets have indeed been a victim to fleas, help them out with some anti-itch relief.
Not only does that provide some immediate relief for your poor pooch but it’ll also prevent further irritation. The flea bite is bad enough in and of itself but when your pet continues to scratch at the bite, it can cause irritation and broken skin, which can lead to skin infection and even more pain.
Flea bites on dogs and cats can also cause further reactions. For example, both dogs and cats can have an allergic reaction to the flea saliva that is injected when they bite.
This condition is known as Flea Allergy Dermatitis (FAD) and it’s actually a leading cause of allergic reaction in dogs.
This allergic reaction goes far beyond the itchy nuisance of flea bites – it can cause severe itching as well as very inflamed skin and even hair loss, as you can see in the below picture of flea bites on a dog.
This allergy to flea bites is just as likely to occur in cats as well, so look out for missing patches of fur, like found in the cat in the picture below.
Flea Allergy Dermatitis (FAD) in cats can also result in dry skin and self-inflicted trauma.
Just one or two flea bites may cause a little skin irritation in the average cat but for a cat with FAD, just one flea bite can result in severe itchiness, irritation and aggravation.
Left untreated, the allergic reaction could become quite severe and in the worst cases, cause severe infection, like in the poor cat below.
Overall, flea bites on humans are no walk in the park but on your precious pets, they can cause a world of misery. So let’s get busy killing the fleas on your pets and making sure they never come back.
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And because we want to end this article on a positive note, here is a final picture of a dead flea.
Because the only good flea is a dead flea. Now go forth and kill some fleas.