Are Dog and Cat Fleas the Same? All You Should Know

Are Dog and Cat Fleas the Same? Photo of a dog and a cat with fleas.

Fleas are just fleas, right? Or are they? Here’s everything you need to know about if are dog and cat fleas the same, and the crucial things that differentiate them!

Technically, dog fleas and cat fleas are different. Dog fleas prefer dogs, and cat fleas prefer cats. However, they can cross over with no problem. The most popular fleas around North America are technically considered cat fleas, but they infect cats and dogs.

How does this all work, and why do you need to know about it? Read on below!

Are cat fleas different from dog fleas?

As briefly mentioned above, yes. Cat fleas, Ctenocephalides felis, are distinctively different from dog fleas, Ctenocephalides canis. You can visually look at a flea and see their differences. Those differences are seen through a microscope and laboratory testing. 

However insignificant those differences seem to us, there are differences between the types of fleas, and professionals in the industry, such as vets and pest control, understand that differentiating them is essential for treatment. We’ll get into that a bit more later!

Will dog fleas go on cats?

You’d think not, right? After all, dog fleas will prefer dogs as opposed to cats. However, dogs fleas will willingly go on cats, and cat fleas will willingly go on dogs. Both will also go on humans, so make sure you remember this when dealing with flea infestations in your household!

As far as a flea is concerned, a host is a host. While dog fleas would technically prefer dogs instead of cats or humans, if they had the choice, they will jump from one host to the next purely to survive. 

Why are there two different types of fleas?

So, if fleas aren’t picky in their host, why are there two different types of fleas?! Why can’t the same flea just be shared?! You’re actually very close to the mark; it turns out! The reason for dog fleas and cat fleas is purely your geographic location!

For example, dog fleas are much more prevalent in European countries. Both dogs and cats have them, but they are considered dog fleas because, when they were named, they were discovered on a dog. Cat fleas, then, are most common in North America and, when discovered, were found on a cat. 

However, you can have dog fleas in North America and cat fleas in Europe. This further complicated things for the average pet parent.

How to find out what kind of fleas my pet has

If you’re feeling confused and frustrated, it’s okay. You certainly aren’t alone. The good news is, this is something you don’t have to worry about! Your vet will be the one to determine what kind of fleas your dog or cat has by running tests.

This is part of why proper vet care is essential when you notice an infestation in your pet’s fur. Determining that it’s the wrong kind of flea will impact the treatment! More on that in a bit, though.

With flea recognition, the thing to remember is that you aren’t expected to know the type of flea. You just have to differentiate fleas from ticks and other pests and get your vet to tell you firmly what it is.

Can my cat have fleas but not my dog?

Many believe cat fleas can’t infect dogs, and vice versa, because cats can have fleas but not dogs (or vice versa). So what’s up with that? In many cases, it could be that your dog (or cat) has fleas first, but you spot and treat the fleas before they spread. 

Your flea-infested animal would have picked them up somewhere that your other pet doesn’t go, and that means that they’ll be infested before the other pet. Hypothetically, both pets would end up with fleas if you left them without treatment long enough. Obviously, this is not a thing you want to try, realistically!

The other reason dogs have fleas but not cats, or vice versa, is because one is vaccinated, whereas the other is not. For example, some vets won’t vaccinate cats if they don’t have a dog in the household. They’ll get flea treatments after so many years instead of every year. So, if they were to come into contact with fleas, they’d be infested much faster and easier than one that was vaccinated regularly.

In another example, perhaps consider that you are buying or adopting a dog or a cat from a rescue. Many don’t vaccinate their rescues since it’ll be the owner’s responsibility to do that later. So, if they were to be infested before they were vaccinated, they would be, whereas your other pet wouldn’t.

Do cats or dogs get more fleas?

Fleas will make a large colony in no time, anywhere they can. Cats and dogs get fleas evenly across the board. The determining factor is immunity/protection.

A pet with up-to-date vaccinations won’t have as severe an infestation as a pet that doesn’t since the vaccinations are intentionally designed to deter and kill fleas. After all, fleas won’t settle where they’re not wanted and safe. Yet another reason to keep your pet’s vaccinations up to date!

Can you use the same flea treatment on cats and dogs?

As introduced above, flea treatments are given after diagnosing the flea problem. There are a few reasons for this:

  • Pest identification
  • Accuracy of flea type
  • Cat skin vs. dog skin

Pest identification

When you think you have a flea problem, you have to take your pet to the vet to make sure. This is because fleas are treated differently from ticks, lice, and other pests.

A proper understanding of the problem is essential, from the approach taken to the actual medication used! Don’t try to diagnose a flea infestation yourself since it can make things harder for you and your pet.

Accuracy of flea type

As we now know, cat fleas are different from dog fleas. While it’s assumed that the flea will be one type or the other, vets will confirm with diagnostic testing to make sure.

The medications prescribed will be different, and one will not work on the other in most cases. This is because the fleas are geographically diagnosed, so vets won’t need to have a lot of the “other” type of medication on hand since it’s rare.

Still, it does happen, and it’s a core reason why vets will wait for diagnostic results before making a prescription!

Cat skin vs. dog skin

There is also a difference between cats and dogs regarding their skin. Flea medication for dogs will be stronger since dogs have stronger skin. The medication can do more without putting their health at risk.

Cats, on the other hand, have sensitive skin. In comparison, their products will be made weaker to be safe for their much weaker skin. Using a dog vaccination for fleas can have disastrous effects on the health and wellbeing of your cat, even if your cat technically has dog fleas.

When your vet prescribes a medicated product for your dog, do not give it to your cat if they have fleas, too. Get a cat-specific product instead from your vet.

In general

There are cat fleas and dog fleas, but the differentiation is actually related to location instead of what infects dogs or cats, respectively. Both cats and dogs can catch each other’s fleas, as can humans.

It’s important to know what type your animal has to offer targeted and effective treatment. Never give a flea product to your pet without a confirmed diagnosis and prescription recommendation from your vet!

There’s a whole lot more to the world of fleas than you thought, right? Know someone who’s going to find this interesting? Or, just want to share the know-how? Go for it!

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Dog Advisory Council

A team whose main goal is to serve knowledge about the canine world. Together since 2012, we thrive to transform and inform, so each dog can live a happy and fulfilling life. Read more about us.