About the Cat Flea

By PetMD Editorial on Jun. 7, 2016

Cat Flea - Ctenocephalides felis

Cat fleas are by far the most common, abundant, and widespread flea species on the planet. Cat fleas aren’t the only species of flea that can be found on domestic cats (and dogs too), but they are definitely the most annoying and hard to get rid of.

The number one source of cat fleas is newly hatched adult fleas that come from your house or yard, where they lie in wait until your pet walks by.

Watch Out for These Diseases

Cat fleas carry a number of diseases that can be harmful to both cats and humans. One disease is cat flea rickettsiosis, which has symptoms similar to murine typhus. Cat flea rickettsiosis can also infect humans. It includes symptoms like headaches, chills, fever, vomiting, and rash.

Specifically Rickettsia typhi causes these clinical signs and is often asymptomatic in cats.

Another dangerous infection that cat fleas can carry is tapeworm. Cat fleas act as a host of both dog and cat tapeworms and can transmit them to both pets and humans.

Lifecycle of the Cat Flea

Under optimal conditions, a cat flea can complete its entire lifecycle in just two weeks. In adverse conditions, the lifecycle of the cat flea can take upwards of one year. Cat fleas like warm, humid environments, so if they make it into your nice, warm home they can be hard to banish.

Cat fleas have four distinct stages in their lifecycle: eggs, larvae, pupae, and adult. Adult fleas spend their entire lives on your pet eating, living, and mating before the female produces eggs that eventually fall off into the environment, where they hatch into larvae. Female cat fleas can lay 20 to 50 eggs per day, which hatch in 2 to 5 days. You can see what a problem just a few cat fleas can quickly turn into.

Flea larvae will eat organic debris until eventually building cocoons and transforming into pupae. This transformation requires a restricted, protected place with at least 75% humidity. The flea pupae can lie dormant for weeks or months, waiting for just the right environmental conditions to hatch into adults. Once adult fleas have hatched, they will sniff out a host (your cat, dog, or another pet) and start the entire process over.

Problem areas in the home where fleas can congregate include pet beds, pet furniture, floor mats, and other areas where your pet spends most of its time. Even if you look for fleas in your home, they are so tiny that you probably will not be able to see them. So how can you identify if your cat has fleas?

Identification and Removal of Cat Fleas

Cat fleas love the warm, moist, safe haven that’s provided in a cat’s furry coat. Two of the main ways to tell if fleas are making a meal out of your cat or pet is to take note of whether they are scratching or biting their skin and fur.

Fleas regurgitate digestive juices onto the skin of a bite site while they suck blood from their prey, and sometimes cats and dogs can have serious allergies to this juice. This allergy is called fleabite allergic dermatitis and can be developed over the course of a dog, cat, or human’s lifetime.

Cats that are allergic to flea bites (flea allergy dermatitis) will exhibit excessive grooming and scratching from just a single bite. It’s also characterized by intense itching, hair loss, reddening of the skin, and secondary infections. The reaction and itching can persist for up to five days.

If you suspect your cat has fleas, check the skin around the base of its tail or under the armpits for tiny, moving black dots. If you find them, you’ll need to treat your pet and your home. For your pets, you can choose from oral flea tablets or topically (externally) applied flea products. Consult your veterinarian for the latest and greatest cat flea control options.

You can also use a flea comb to comb your animal and look for flea “dirt” (the feces of fleas) which can alert you to an infestation even without seeing live fleas.

Preventing Cat Fleas and Treating Your Home

The best way to keep cat fleas from taking over your home or pet is by not giving them a chance in the first place. In your home and yard you can prevent a cat flea infestation by regularly cleaning out the areas where your pet rests. There are also traditional chemical and pesticide sprays, shampoos, and dusts you can use in addition to some of the safer, modern, chemical-free products.

You should be monitoring your pet for scratching and biting on a regular basis. If you notice your cat scratching or grooming itself more than usual, buy a flea comb and check by combing through your cat’s fur. The fleas will get caught at the base of the comb’s teeth. If you find fleas, call your vet and explore your flea removal options immediately. Be aware that cat fleas can pose a special danger to kittens and old or infirm cats.

A Special Danger: Kittens and Cat Fleas

In addition to the nasty diseases that fleas can carry and transmit to your cat, they pose a danger to kittens in two ways: anemia and toxic reactions to flea dips.

According to William Miller Jr., VMD and professor of dermatology at Cornell University’s College of Veterinary Medicine, fleas don’t actually bite. They stick their proboscis (a long, tubular, sucking mouthpart) into a kitten’s skin and suck their blood. If a kitten, an old cat, or a debilitated cat is carrying a large amount of fleas, the fleas can cause anemia and even death.

On the other hand, if you’ve got a litter of kittens that you want to treat for fleas, you’ve got to be careful to use a vet-approved medication made specifically for kittens.

Flea medications for kittens are determined by the kitten’s age and weight, and if the guidelines aren’t adhered to they can be deadly. Do not use natural, homeopathic, essential oil-based treatments on your kitten either, as these can be just as harmful.

Kittens over four weeks old (some medications list eight weeks old as the minimum) may be treated with medications like Capstar if they meet the minimum weight requirement. Regardless of the treatment, you’ll need to treat the mother cat as well as your home and yard.

Always check with your veterinarian before beginning any type of flea treatment regimen. Your cat may have a health condition that can be worsened by the toxic effects of some flea medications.

Image: K. Walker, Museum Victoria (Creative Commons Attribution 3.0 Australia License

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