Indoor Cats Have Fleas Too. Where Do They Come From?


Fleas are a common external parasite that live on the blood of cats, dogs, and other mammals. They have a complete four-stage lifecycle consisting of egg, larva, pupa, and adult. Fleas can survive for months without a host in their pupal stage. Once they emerge as adults, fleas jump onto hosts to feed on blood. A flea can lay up to 50 eggs per day, allowing populations to rapidly increase.

Even indoor cats can get fleas, contrary to popular belief. Fleas can come into the home on the cat, other pets, clothes, and shoes. They can also be brought inside by rodents and wildlife. Once inside, flea eggs can fall off the pet and accumulate in carpets and bedding areas. Without preventive treatment, these eggs can hatch into larvae and develop into biting adult fleas in as little as two weeks.

Fleas Can Come From Outside

One of the most common ways indoor cats can get fleas is by the fleas hitchhiking inside on other pets or people coming from outside. Fleas living outdoors, especially in areas like tall grass, bushes, and under brush, can easily jump onto pets and people walking by. The fleas can then be carried inside and transferred to indoor cats.

For example, if you have a dog that goes outside, fleas may hop onto the dog while it’s out in the yard or on a walk. When the dog comes back inside, those fleas can then spread to your indoor cats. This is why it’s important to treat outdoor pets with flea prevention medications regularly (source).

Fleas may also come indoors through open doors, windows, or other openings. If these access points are not well sealed or screened, fleas can crawl or jump inside seeking a host. Keeping doors and windows closed as much as possible can help prevent this.

Flea Eggs Can Be in Your Home

Even if your indoor cat never goes outside, flea eggs from a prior infestation can survive in your home and hatch later. Flea eggs are tiny and can fall into cracks in floors and furniture. They are resilient and can remain dormant for months waiting to hatch.

Regular and thorough vacuuming is crucial for getting rid of flea eggs. Vacuum all floors, carpets, furniture, and pet bedding frequently. Be sure to empty the vacuum or replace bags after each use. Steam cleaning carpets and washing bedding on a hot setting can also kill lingering flea eggs.

In addition to vacuuming, wash any pet beds, pillows, blankets or soft toys your cat uses. Hard surfaces like floors and furniture can be cleaned with soap and water. Getting rid of flea eggs is key to preventing future infestations and keeping fleas off your indoor cat.

Some Flea Treatments Don’t Work

Many flea collars and shampoos don’t effectively kill all life stages of fleas. According to a 2016 review, some over-the-counter flea treatments like collars and shampoos often don’t provide sufficient protection against flea infestations ( This is because they may not penetrate deep enough into the cat’s fur to reach the skin where fleas feed. Additionally, these products may only kill adult fleas but not eggs or larvae.

Veterinarian-prescribed oral and topical flea treatments have been found to be much more effective. A 2020 study showed that a new oral flea treatment provided 100% prevention of flea reproduction for over a month after a single dose ( Topical treatments like those containing afoxolaner were also found highly effective, providing nearly 100% kill of adult fleas within 48 hours (

For the best protection against fleas, pet owners should use oral or topical flea control products prescribed by their veterinarian. Over-the-counter flea collars and shampoos often will not provide adequate flea control.

Fleas Can Come From Rodents

Mice or other rodents can unknowingly carry fleas inside your home. Mice and rats often have fleas living on them that can jump off and infest your house. According to, many rodents naturally carry fleas with them as they move from place to place.

If a mouse gets into your home, the fleas can quickly spread throughout your house and start biting your pets. These fleas can lay eggs that will continue the infestation even after the rodent is gone, according to

To prevent fleas from entering with rodents, be sure to seal any possible entry points into your home. Check for small cracks or holes inside and outside that mice can squeeze through and plug them up. Install weatherstripping around doors and windows as well. Traps or other rodent control measures can also help keep them out of your house.

Check All Pets in the Home

Even if your cat is indoors, other pets can bring in fleas. Fleas move quickly from one host to another, infesting any warm-blooded animal. If you have both indoor and outdoor pets, or multiple indoor pets, it’s important to treat them all for fleas.

According to Tri County Pest Control, you should treat all pets in the household with vet-recommended prevention on the same day you treat your home. Fleas can survive without a host for many months, so you need to treat every pet in your home even if they don’t appear to have fleas currently. Any untreated pet can allow the flea lifecycle to continue.

By using veterinarian-recommended flea control products on every dog, cat, and other furry pets in your home, you stop fleas from being able to jump from one host to another. This is a key part of protecting indoor cats from getting fleas even if they never go outside.

Inspect and Treat Your Home

Thoroughly cleaning your home is an important part of getting rid of a flea infestation. Be sure to focus on the following areas:

Vacuum all carpets, rugs, and furniture thoroughly, including underneath cushions and in crevices. The strong suction will help remove eggs and larvae. Remember to immediately dispose of the vacuum bag afterwards.

Wash all pet bedding, blankets, cushions, and other washable fabrics in hot, soapy water. The heat will kill fleas, larvae, and eggs.

Consider having your home professionally treated by a pest control company. They can spray pesticides and insect growth regulators that kill fleas and prevent future infestations. As noted by Zero Tolerance Pest Control, “Martin was professional and friendly from the first phone call to book him. He was highly recommended to treat our home for fleas and got rid of them for good.” [1]

Continue monitoring your home and repeating treatments as needed until all signs of fleas are gone.

Maintain Flea Prevention

One of the most important things you can do to prevent fleas on your indoor cat is maintain year-round flea prevention medication and treatment. Work closely with your veterinarian to keep your cat on an effective flea prevention medication at all times.

Many pet owners make the mistake of stopping flea medication during the winter months or when their cat lives exclusively indoors. However, even indoor cats are still at risk for fleas. Eggs and larvae can survive for months in your home waiting to hatch, and your cat can pick up fleas from another household pet or rodents that get inside.

By maintaining diligent flea prevention medication prescribed by your vet, you can help ensure your indoor cat stays protected against fleas year-round. Your veterinarian can recommend the best monthly spot-on treatments, pills, or collars for your cat that rapidly kill adult fleas and prevent development of flea eggs and larvae. This helps break the flea life cycle and prevents flea infestations before they start.

Don’t wait until you see fleas on your indoor cat to take action. Consistent and proactive flea prevention medication for indoor cats is essential to keeping your home flea-free.

Monitor for Signs of Fleas

It’s important to regularly check your cat’s skin and coat for any signs of fleas. Use a fine-toothed comb to brush through your cat’s fur and look for any fleas or flea dirt (flea feces that look like black pepper). Pay close attention around the neck, base of the tail, and belly where fleas often congregate.

Catching an infestation early allows you to treat it quickly before it spreads and causes misery for your cat. Signs to look for include:

  • Small dark specks in your cat’s fur that could be flea dirt
  • Seeing live fleas crawling through the fur
  • Intense scratching or skin irritation
  • Balding patches or scabs from scratching
  • Flea allergy dermatitis with red, inflamed skin

If you spot any of these signs, treat your cat and home right away. The earlier treatment begins, the faster you can eliminate fleas and prevent misery for your cat.


In summary, indoor cats can still get fleas, even though they do not go outside. Fleas can hitch a ride into your home on people, other pets, or rodents. They can also come from flea eggs that are dormant in your home. It’s important to regularly check your cat and home for signs of fleas. Using effective flea prevention medication on all pets in the household is key, as is thoroughly cleaning and treating your home. With vigilance and proper prevention, you can help protect your indoor cats from dealing with irritating flea infestations.

Indoor cats can still get fleas but consistent prevention both on your cat and in your home is the best way to avoid an infestation. Keep an eye out for signs of fleas and be proactive with treatments to keep your indoor cat flea-free.

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