How Do Dogs Get Fleas?

If you come home from the dog park or an evening walk and notice your dog seems especially itchy, there’s a chance fleas could be the culprit.

Fleas are small, dark-colored parasites that survive by feeding on animals, including your precious pup. Once a flea has found a host, they bite and drink the animal’s blood, leaving behind itchy red bumps.

If you think your dog has fleas, don’t panic. You can get rid of these pesky parasites and prevent them in the future with some simple—though diligent—care.

Unfortunately, it’s extremely common for dogs to get fleas. And they can contract fleas in more than one way, says Michael Kearley, DVM, a veterinarian in Tampa, Florida. “Long story short, they get fleas from the environment, like in the grass and wooded areas,” he says.

Dogs can also get fleas from:

• Your yard: You might not think of your backyard as the “great outdoors,” but there are still plenty of opportunities for a flea to jump on your doggo directly from your grass. Flea eggs often drop into your yard from other animals. After the eggs hatch and mature into larvae and adult fleas, the fleas are waiting in the grass, ready to jump on your dog.
• Wild or stray animals: If your dog has a brush with local wildlife (such as raccoons, rabbits, or squirrels,) or stray cats or dogs, they might catch live fleas that hop onto them directly from that animal.
• Other dogs: Ditto for other dogs—it’s easy for your pup to be exposed to fleas when playing with (or just being in close contact with) another canine pal.
• You: Sorry to say but yes, you can give fleas to your fur baby, too. If you’re outside and a flea jumps on you, your clothing, or your shoes and then you come inside to greet your dog, the flea can then jump onto them to feed.

In most areas, fleas are more prevalent during spring and summer, when the weather is warm (at least 70 F). But your dog can get fleas at any point of the year because these parasites can survive colder temperatures—especially when indoors in a cozy home.

Signs that your dog has fleas include:

• Black dots known as “flea dirt” (digested blood that the flea poops out) where your dog has been sitting or lying down
• Flea dirt in your dog’s fur
• Itching, biting, and scratching at the skin
• Hair loss
• Hot spots
• Red skin with bumps

If you see any of these symptoms, take a closer look at your dog’s fur and skin.

“A common place for fleas to hang out is on the thinly haired belly, as well as at the base of the tail,” says Sandra Mitchell, DVM, DABVP, at All Creatures Veterinary Services based in Eddington, Maine. “A careful look in these areas may reveal the insect moving about, or a salt and pepper look that indicates flea eggs and debris.”

You can find this debris, or flea dirt, on your dog’s skin, but it can also be found on your pup’s bedding, your carpet, or wherever your furry friend may have been lying down.

The flea eggs are harder to spot because they’re microscopic—about the size of a grain of sand. But if you see a white, oval shape on the surface of your dog’s bed, that’s likely an egg and it’ll hatch a few days later into flea larva.

Fleas aren’t just gross—they can also be harmful to your pet because they can carry diseases and even cause anemia. Dogs can also develop an allergy to flea bites. This means it’s super important that you act quickly if you suspect your dog has fleas.

If your pooch is itchier than usual or if you’ve seen evidence of fleas, visit your veterinarian as soon as you can get an appointment. Your vet will give you advice on what to do next and may prescribe medication to treat your dog’s current infestation.

Depending on your dog’s lifestyle (including if they swim or are bathed more than once a month) and medical conditions, your vet may prescribe a chewable like Simparica®, NexGard®, or Comfortis™ or, a spot-on (topical) preventative like Bravecto®.

Follow your veterinarian’s instructions to get rid of the fleas. This can include treating your dog with a fast-acting flea killer like Capstar® or grooming with a flea comb and dog-friendly shampoo.

When your dog has fleas, chances are the parasites have jumped to other areas of your house. To get rid of fleas that may be lingering in your home:

• Wash all toys and bedding (both yours and your pets’) in hot, soapy water and dry them on the hottest heat setting
• Vacuum your carpet, rugs, and anywhere your pup lies down (you may need to vacuum regularly for several days if the infestation is intense)
• Break out a bottle of flea spray and apply as the instructions say

Fleas from your dog can find their way onto your other pets, too. Think of your dog as a saltshaker, dropping flea eggs wherever they walk or sit down. These flea eggs hatch and mature into adult fleas in 90 days, waiting to jump back onto your pooch or onto other animals in your home, continuing the infestation.

“It’s critical that every pet in the house be treated, including animals such as rabbits and ferrets, or treatment is unlikely to be successful,” Dr. Mitchell says. “The process is sped up dramatically if the environment is also treated.”

“Fleas are way easier to prevent than treat,” Dr. Kearley says. So to stop the parasites from returning to bite your pup, begin a flea prevention regimen—and stick to it.

There are many different types of products that can kill and prevent fleas on your dog, including topical medications like Bravecto®, tasty chews like Nexgard®, and collars like Seresto®.

Remember: Fleas can be a nuisance year-round, so it’s important to provide your furry best friend with the necessary protection.

Expert input provided by Michael Kearley, DVM, and Sandra Mitchell, DVM, DABVP. This content was medically reviewed by Chewy vets.