Despite being tiny, fleas are one of the most common and frustrating external parasites affecting cats. A single flea can lay up to 50 eggs per day, and the flea life cycle means that by the time you see adult fleas on your cat, there may be thousands of eggs, larvae, and pupae throughout your home.
The Flea Life Cycle
Understanding the flea life cycle is key to effective treatment. Adult fleas live on the cat and feed on blood, mate, and lay eggs. These eggs fall off the cat and into the environment. Larvae hatch from eggs and feed on organic debris in carpets, bedding, and cracks in flooring. After about a week, larvae spin cocoons and become pupae. Pupae can remain dormant for months in the right conditions. Adult fleas emerge from cocoons when they detect vibration, heat, and carbon dioxide from a potential host.
Year-Round Prevention
Modern flea preventives — available as topical spot treatments, oral medications, and collars — are remarkably safe and effective when used as directed. Most veterinarians recommend year-round prevention even in cold climates, because heated homes create ideal conditions for fleas year-round, and even brief gaps in coverage can allow a new infestation to establish.
If You Find Fleas
If you find fleas on your cat, treatment needs to address both the cat and the environment. Bathe your cat with a gentle cat shampoo to remove adult fleas. Use a veterinarian-recommended flea preventive to kill remaining fleas and prevent reinfestation. Vacuum the entire home thoroughly and discard the vacuum bag outside. Wash all bedding in hot water. In severe infestations, environmental flea spray or professional pest treatment may be necessary.