How Do Cats Get Fleas?

And how to treat a flea infestation.

Indoor cat with fleas

Hollywood may have taught us that cats’ number one enemy is mice — but that’s not actually true. Fleas are enemy number one, and sadly all cats can get fleas if they’re not on a reliable preventative, even if they’re strictly indoor pets.

But how is that even possible?

The Dodo reached out to Dr. Jennifer Coates, a veterinarian and advisor for Pet News Daily, and Dr. Megan Conrad, a veterinarian and advisor at Hello Ralphie, to find out how cats get fleas, even if they never go outside.

How do outdoor cats get fleas?

If your cat’s allowed outdoors, he can get fleas from tons of different places outside — especially moist and shady areas, like a leaf pile or those shrubs in the corner of your lawn.

Cats can also get fleas by coming into contact with other animals who have fleas. “Many different types of animals can have fleas on them, including dogs, cats, squirrels and raccoons,” Dr. Coates told The Dodo.

“Adult fleas prefer to stay on a warm host, but the eggs they lay are designed to fall off into the environment, where they hatch into larvae, then pupae and eventually into new adults that are eager to hop aboard the first animal, like your cat, that comes by,” Dr. Coates said.

How do indoor cats get fleas?

“Indoor cats can get [fleas] as well,” Dr. Conrad told The Dodo — and there are actually a few different ways this can happen.

  • They get a ride in on your dog. “Cats who live with dogs (even if the cats don’t interact much with them) can easily get one flea on them, which can lead to thousands more,” Dr. Conrad said.
  • They jump through an open window. Indoor cats can even get fleas by merely sitting near an open window — even if that window is screened in.
  • They hitch a ride on you! Fleas can even latch onto your clothing or hair for a free ride inside. So in some cases, your cat could be getting the fleas from you. It’s gross, but it’s true!

And all it takes is one flea to cause an infestation on your cat or in your home. “Fleas are prolific breeders,” Dr. Coates said. “One adult female can lay up to 50 eggs per day and 2,000 fleas over her lifetime.”

What to do if you find fleas on your cat

Because fleas are so problematic, it’s important to get a flea situation under control sooner rather than later. Here’s how to nip an infestation in the bud.

Treat your cat for fleas

First, you need to get your cat flea-free and set her up with a prevention plan.

According to Dr. Coates, if you see fleas on your cat, the best thing to do is to use a product that kills off existing fleas and prevents them from coming back.

“Cats with fleas should be treated with a safe and effective flea control product containing active ingredients that kill adult fleas and that sterilize flea eggs and prevent immature fleas from maturing into adults,” Dr. Coates said.

Try Bravecto Topical Solution for Cats from Chewy for $53.49

Check out this list of vet-recommended flea treatments and consult your vet about which one may be best for your cat. Your vet can help you pick the best product based on your cat’s age, health and lifestyle.

And before applying a treatment, you can give your cat a bath using a flea shampoo to give your cat instant relief. “Flea shampoo can be a good starting point for treating a bad infestation,” Dr. Conrad said. But keep in mind that it only kills the adult fleas living in your cat’s coat. Therefore, a bath needs to be followed up with a heavier duty treatment.

“Only use flea shampoo that is labeled for cats,” Dr. Conrad added. “It is very easy for cats to absorb too much of the chemical that kills fleas from the shampoo,” so definitely don’t use a shampoo that is specifically labeled to be used on dogs or other animals.

Treat other pets for fleas

And you can’t just treat your cat if there are other animals in the house. Every dog or cat in the home will need to be treated as well, since it’s likely that they, too, have fleas.

Again, using a topical or oral treatment to treat your pets is a safe and easy way to keep the flea count down and prevent more fleas from hatching. Consult your vet to figure out which preventative treatments are best for all your animals.

Treat your home for fleas

You’ll also have to de-flea your home, too. “This may include washing all bedding in hot water, using flea killing chemicals (either store bought or with an exterminator [in severe infestation cases]), and treating your yard,” Dr. Conrad said.

Dr. Coates recommended thoroughly vacuuming your carpets, floors and upholstery, too, to remove immature fleas.

“Once you start the process, it could take up [to] two months to get it fully under control,” Dr. Conrad said. And she said it’s especially important to keep your pets’ flea prevention plans up to date throughout the entire process — though you should use prevention medications regularly throughout your pets’ life.

Dealing with fleas isn’t fun for anyone, so that’s why it’s important to use the right prevention plan and check your cat for fleas often (even if she doesn’t go outside) to make sure these itchy, scratchy critters don’t ruin your cat’s good time.

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