• Adult fleas are only part of the problem. Immature fleas (eggs and larvae) contribute to flea infestation, too.
  • Your pet does not have to go outside to get fleas.
  • Your veterinarian is a reliable source of information on safe and effective flea control products for your pet and home.

What Are Fleas?

Fleas are blood-feeding parasites that can infest many species of birds and mammals. Although fleas on dogs and cats don’t infest people, fleas may bite people if an area is heavily infested. Flea infestation is one of the most common medical problems veterinarians see, and pets suffer greatly from this condition. Flea bites can trigger severe allergic reactions in some pets. The intense itching caused by flea infestation causes pets to scratch and bite themselves. This can lead to skin wounds, skin infections, and general misery for your pet. Even if your pet is not allergic to flea bites, fleas can transmit serious diseases, such as bartonellosis (the bacteria that causes “cat scratch disease” in people), and other parasites, like tapeworms.

How Do Animals Become Infested With Fleas?

Fleas are very successful parasites. Temperature and humidity extremes can kill them, but they can survive for long periods of time under a surprising range of conditions. Developing fleas can even become dormant for many months if there are no hosts available.

If your pet spends time outside, in kennels, or around other animals, the risk of picking up fleas increases. However, even a completely indoor pet can become infested with fleas. Because the temperature and humidity conditions inside your home are fairly stable, fleas can live there with relative ease. In this way, fleas can live in colder regions of the country, surviving climate conditions that would otherwise be intolerable. Once they have entered a house, fleas can multiply very well under favorable year-round conditions, adding to the challenge of controlling them in a home environment.

You can bring fleas into your home on your clothing, and any people or animals that come into your home can also bring fleas with them. Once fleas find a host, they begin to feed almost immediately. They lay large numbers of eggs, which eventually mature into new fleas that continue the infestation. Adult fleas may remain on an animal, but the eggs and larvae fall off the animal and remain in the environment. Flea larvae are mobile, and they can hide in places such as carpeting, bedding, furniture, and baseboards. Once they mature, they take the first opportunity to jump onto an animal or person and begin to feed, continuing their life cycle.

How Can I Tell If My Pet Has Fleas?

Fleas may not be easily visible on your pet. If an infestation is heavy, you may see fleas on the animal’s skin, or you may find them by combing your pet with a flea comb. Adult fleas are the easiest stage of the parasite to find, but they account for less than 5% of an infestation. The other stages (eggs, larvae, and pupae), which make up the other 95%, are smaller and more difficult to find.

You may also find small black/brown specks on your pet’s skin or bedding. These specks look like tiny coffee grounds and are commonly called “flea dirt.” Flea dirt is the feces of adult fleas and is actually the digested blood of the host. When the dark particles get wet, the red color returns, which may help with identification.

Some pets are allergic to fleas and can become intensely itchy from a single flea bite, whereas other pets may experience mild itching or none at all. Just because your pet isn’t scratching doesn’t mean there are no fleas. When in doubt, check it out!

How Can I Treat the Problem?

Because flea infestations involve multiple life stages, an effective treatment strategy targets as many stages as possible. If you believe your pet is infested with fleas, begin with a trip to your veterinarian. Your pet may have a skin infection or other problem that needs attention. Once your pet has been examined, your veterinarian can recommend a safe and effective product that you can use to kill the fleas. Some products specifically target adult fleas, while others also target the immature stages, like eggs and larvae. Regardless of what product is used, multiple treatments are generally required to completely eliminate an infestation. If you have multiple pets in your home, each animal should be treated with an appropriate product. In some cases, the house may also need to be treated to exterminate fleas. Products are also available for treating the yard and outdoors. Care must be taken, however, as these products may seep into the soil over time and affect groundwater. A “greener” strategy may be to focus on targeting fleas on your pets and in the home.

Although fleas have been around for a long time, many products are available today that can safely and effectively eliminate them. Ask your veterinarian about the best way to control fleas, and keep them from endangering your pets!

This article was reviewed by a Veterinarian.