Where Do Fleas Come From?

Here’s where you can find fleas outside and inside your home 🦟

You know all about fleas — and maybe your pet even had some once upon a time.

But have you ever wondered where these little bugs live when they aren’t living with you? They seem to just appear without warning — so where do fleas come from?

The Dodo reached out to Dr. Jamie Richardson, medical chief of staff at Small Door Veterinary in New York City, Dr. Robin K. Moore, a veterinarian and owner of East BayAnimal Hospital in Largo, Florida, and Dr. Linda Simon, a veterinary surgeon and consultant for Five Barks, to find out.

Where do fleas live?

Fleas live on their animal hosts — and they don’t discriminate when it comes to which animals they choose (as long as their host has enough fur or hair to keep them warm and happy). So while we mostly hear about fleas living on dogs and cats, fleas can also be found on wild animals, like deer, raccoons or possums.

And while fleas don’t live on people, they can bite them.

But fleas don’t live on animals their whole lives. A flea’s life cycle goes through four stages — egg, larvae, pupa and adult. Adult fleas need to live on their animal hosts to survive off their blood, but flea eggs, larvae and pupae can live pretty much anywhere.

So if there are adult fleas living on your pet, there are likely going to be fleas living somewhere in your home, too. Fleas survive best in areas like carpet fibers, cracks between hardwood floorboards and unfinished concrete floors in damp basements. “They can also be found in bedding, rugs, blankets and plush toys,” Dr. Richardson told The Dodo.

Where do fleas live outside?

When fleas aren’t living in an animal’s fur, you can typically find them in grassy or other shady areas — especially in the warmer months.

But keep in mind that dogs can get fleas during any time of the year in any location.

“Fleas are present all over the world on most animals,” Dr. Simon told The Dodo. “They are most prevalent in warmer climates, but the use of central heating has meant that they are present all year round in most countries.” (These parasites prefer higher temperatures, though, so they’ll be even more active in hotter climates and warmer months.)

It’s also important to know that fleas who live outside aren’t planning on being there for long, and once they’re big enough to jump, they’ll leap right onto an animal who passes by and looks like a sufficient host.

How do pets get fleas?

According to Dr. Richardson, your pet can pick up fleas both inside and outside of your home.

One way your pet can get fleas while inside is from another pet with a flea infestation. For example, if you have a cat who strictly stays inside, but your dog picks up fleas on a walk, fleas can catch a ride on your pup and jump over to bite your cat.

“They may also be brought indoors by mice, humans or on secondhand items,” Dr. Richardson said. “Both fleas and flea eggs can stick to shoes or clothing from outdoors and drop onto the floors of your home.”

Dr. Richardson recommends thoroughly checking secondhand items for fleas before bringing them into your home and immediately washing them in hot water.

If you think your pet picked up fleas somewhere outside of your house, Dr. Richardson said it can happen at a pet day care, boarding facilities or the groomer’s, and on walks.

“Check your dog after he’s been to places like the dog park, a backyard or out for a long walk, especially in grassy or wooded areas,” Dr. Richardson said.

How to prevent fleas in pets

All pets in your home should be on a flea preventative (even your indoor-only cat!).

“A monthly preventative product is a MUST,” Dr. Moore told The Dodo. “Your veterinarian can make a product recommendation that is best for you and your pet.”

Like topical product Bravecto Topical Solution for Dogs from Chewy for $53.99

Or an oral product like Bravecto Soft Chews for Dogs from Chewy for $63.99

For cats, try the oral medication Credelio from Chewy for $16.47

And be sure to check your pets often for any signs of fleas.

“Practice routine brushing and bathing to keep their coat and skin healthy and allow you to monitor if there is any evidence of flea infestation,” Dr. Moore said.

And if you’re already dealing with a flea infestation, you’re going to have to treat both your pet and your home to get rid of them and prevent new infestations from popping up.

To treat your dog or your cat, a flea preventative should do the trick. To treat your home, you should vacuum everything you can, clean all soft surfaces — like pet bedding, cushions and blankets — and possibly call an exterminator if you want to be extra sure that the fleas are gone.

While fleas are definitely a nuisance, they aren’t the absolute end of the world. As long as you make sure you’re consistent with prevention, you should live happily flea-less.We independently pick all the products we recommend because we love them and think you will too. If you buy a product from a link on our site, we may earn a commission.