Debunking Five Myths About Fleas on Dogs and Cats

Tuesday, July 19, 2016 | Dog HealthHealthPet HealthPet Tips


Many pet parents feel horrified, even mortified, when they find fleas on their four-legged furry friends. And some owners are puzzled by the finding, especially if the cat is an “indoor-only” pet or the dog is treated with a monthly flea-control product. Knowing the facts about fleas can help you better understand how pets can get these hardy, annoying blood-drinkers and why your veterinarian may recommend year-round flea control.


A few fleas are no big deal.

Maybe. But it’s much more likely that you’re seeing only the tip of the iceberg. Whether you should worry depends on several factors:

  • How many fleas you’re finding on your dog or cat
  • Whether your pet has been treated previously with a flea-control product
  • And if your cat or dog has been treated, which product was used and when was it last applied or given.

If your pet was treated with a product that provides month-long adult flea control (and hopefully an ingredient that stops insect growth) and you’re finding five or fewer adult fleas, then you may be seeing “hitchhiker” fleas. These are fleas that your dog or cat picks up outdoors from locations frequented by other pets, stray or feral animals, or wildlife such as opossums and raccoons. Fleas also can hitch a ride into your home on you and your clothing, visitors whose pets may have fleas and even visiting pets.

If your pet is not already being treated with a flea-control product and you find fleas, you could have a problem, and the time to take action is now. The fleas we see on pets are adults — what we don’t see are the immature stages (eggs, larvae and pupae) that are developing in the environment.


The only pets in the home that need to be treated are those with fleas.

Not true! Especially if you want to avoid a flea infestation. (A flea infestation means adult fleas are reproducing on your pet and all of the immature flea stages are present in the environment that your pet frequents.) All pets in the home must be treated to control fleas, and you’ll want to treat the home environment as well.

Although the fleas that infest cats and dogs do not jump from one pet to another, any untreated pet can become the new home for fleas if immature fleas are present in the environment. And it’s possible that an untreated pet is the actual source of fleas. Because some pets are more sensitive to fleas than others, a pet could have fleas but not give any signs of itchiness.


Homes without carpeting cannot become infested with fleas.

Wrong. Fleas are opportunistic and their eggs, larvae and pupae are capable of hiding just about anywhere. It’s not uncommon to find immature flea life stages in the cracks between hardwood, laminate or tile floor coverings and along baseboards. They’ll also hide in your pet’s (and your!) bedding, even within or under upholstered furniture where your pet rests.


If you treat your pet with a flea control product, you won’t see fleas on him.

False! With topically applied products, most adult fleas are killed within hours, not several seconds or minutes as some people might expect. In addition, flea-infested environments will act as a constant source of new fleas. These recently acquired fleas may be the “live” fleas you’re seeing on your treated cat or dog. The good news is that they should be dead within 24 hours or less.


Once fleas are removed from your pet, the flea problem is solved.

If only it were that simple! Your dog or cat may not have fleas after treatment, but the adult fleas found on pets are only 5 percent of the flea population in your pet’s environment. The other 95 percent are hiding as immature stages — eggs, larvae and pupae — in the environment and still pose a risk to your pet. That’s why veterinarians recommend treating your home environment, as well as treating all pets in the home for more than one month. And depending on the severity of the problem, you may need to call an exterminator or use over-the-counter insecticides to treat your home. Ask your veterinarian for a flea-control product that kills adult fleas and keeps flea eggs and larvae from developing into adults.


RELATED: Debunking Common Myths About Ticks and Pets

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