Where Do Fleas Even Come From?


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 even come from to begin with? They seem to just appear without warning — so where do they live when they aren’t living with you?

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

What are fleas?

Fleas are tiny wingless insects that feed on the blood of animals in order to survive.

The funny thing about fleas is you typically don't even know they’re around until you start scratching and itching from flea bites.

Where do fleas live?

Fleas love living 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 primarily know of fleas living on dogs and cats, fleas can also be found on wild animals, like deer, raccoons or possums.

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.

It’s 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 does a dog get fleas?

According to Dr. Richardson, there are two main places your pet can pick up fleas: inside or outside of your home.

Inside the home

One way your pet can get fleas while inside is by picking them up from another pet in your home who may have an infestation. For example, if you have a cat who strictly stays inside, but your dog picks up fleas on a walk, fleas could ride in 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 told The Dodo. “Both fleas and flea eggs can stick to shoes or clothing from outdoors and drop onto the floors of your home.”

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, so if you receive any of these secondhand, thoroughly check them for fleas before bringing them into your home, and immediately wash them in hot water,” Dr. Richardson recommended.

Outside the home

If you think your pet picked up fleas somewhere outside of your house, Dr. Richardson said it could happen at a pet daycare, boarding facilities or even the groomer.

But since they also live outdoors (and on wild animals), your dog could also have picked them up on a walk. “Fleas can survive outdoors for a long period of time, especially during warm, humid weather,” Dr. Richardson said. “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.”

How to prevent fleas in dogs

If your pet goes outside or lives indoors only, you should use a preventative method to stop fleas from even trying to infest him to begin with.

“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 a topical product like Revolution from Chewy for $128.19

Or an oral product like Bravecto Soft Chews for Dogs from Chewy for $59.99

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.

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.
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