Even if your pet lives indoors, fleas and flea eggs can still make their way into your pet’s everyday environment. They can come into the house on your clothing, your pet's fur, other family pets or any other visitor who enters your home. Once inside, fleas can hide behind baseboards, in your pet’s bedding or blankets, in flooring or carpeting and other areas in your home. They can often be found in your yard as well.

While a flea infestation is a problem on its own, fleas can also cause diseases that threaten your pet’s health and happiness. Here are the main four conditions you need to know about:

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Tapeworms are parasitic worms passed to your pet from unknowingly ingesting infected fleas. Cats contract tapeworms when they ingest an infected flea. This most commonly happens while grooming themselves or other animals.

Once in the digestive system, tapeworms attach themselves to the intestinal lining with sharp, beak-like mouthparts to steal nutrients from your pet. Most pets won’t show obvious symptoms, but you may notice them scratching their rear or scooting around or find rice-like worm segments in their stool or around their tail. They may also experience malnutrition and weight loss.

Flea Allergy Dermatitis (FAD)

Flea allergy dermatitis is one of the most common reasons people take their pets to the veterinarian.

Substances in flea saliva can trigger an immune response in your pet’s skin. This can cause intense irritation and itchiness beyond the bite itself — you may see or feel small scab-like bumps on your pet’s skin. Miserable symptoms like hair loss and skin infections will continue until the fleas are controlled.

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Fleas can pass along bartonellosis, an infection caused by Bartonella bacteria, most commonly Bartonella henslea. Cats contract this disease through close contact with fleas and their feces. Dogs can be infected with Bartonella potentially linked to fleas as well.

Infected fleas shed the bacteria in their feces and drop waste right on your pet’s skin, which eventually infects the pet, especially cats.

Several conditions have been linked to Bartonella infections, including mouth and gum disease, eye inflammation and heart disease. A main concern is that cats can carry the bacteria in their system without showing obvious clinical signs right away for more than a year, potentially passing it to other fleas and, in turn, other pets.


Because of their rapid reproductive rate, one flea can quickly turn into hundreds. If a large number of fleas bite and draw blood, your pet can develop anemia. This serious condition must be promptly addressed and may require extended vet care, especially in puppies and kittens. Often, treatment includes killing the fleas and giving the pet time to recover.

Symptoms of anemia include weakness, lethargy, rapid breathing and potentially death. With severe infestations, treat the home and surrounding outdoor areas as well as your pet to address the infestation and help prevent fleas from reinfesting.

Because fleas can be found almost anywhere and have the ability to stay active year round — especially in a warm home — it’s difficult to avoid them completely. To help protect your pet from fleas, use a monthly flea prevention product all year long. Consider keeping your pets on a monthly flea prevention program with products that kill through contact, so fleas do not have to bite your pet for the treatment to work.

To learn more about solutions for fleas, check out the Advantage Fleaction Plan.

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