Ringworm in Cats: Signs, Treatment & Spread
Start here
Ringworm is a common, contagious fungal skin infection in cats — despite the name, it has nothing to do with worms. It causes circular patches of hair loss, scaly or crusty skin, and sometimes redness or itching, often on the face, ears and paws. It's treatable but stubborn, and importantly it's zoonotic — it spreads to people and other pets, so prompt treatment and cleaning matter.
It spreads to people and pets
Ringworm is contagious to humans and other animals. Children, elderly people, and anyone with a weakened immune system are more susceptible. If you handle an infected cat, wash your hands well, and see your own doctor if you develop a red, ring-shaped, itchy patch of skin. Keep an infected cat separated from other pets and from vulnerable family members while it's being treated.
The good news: in otherwise healthy people and pets, ringworm is usually mild and very treatable. But because it spreads through direct contact and contaminated environments — bedding, brushes, furniture — controlling it means treating the cat and cleaning the home together.
What ringworm actually is
Ringworm is caused by microscopic fungi called dermatophytes that feed on keratin in skin, hair and nails. In cats the most common species is Microsporum canis. The fungus spreads through direct contact with an infected animal or through spores shed into the environment, which can survive for many months on surfaces and in dust.
Kittens, long-haired cats, and cats that are young, elderly, stressed or immunocompromised are more prone to infection. Some cats — especially long-haired ones — can even carry and spread the fungus while showing few or no visible signs.
Signs to watch for
The classic patch is round, but ringworm can look like many other skin problems:
- Circular patches of hair loss, often with a scaly or crusty center
- Broken, stubbly hairs around the lesion
- Flaky, red, or crusty skin, commonly on the face, ear tips and paws
- Brittle or deformed claws if nails are involved
- Mild or no itching in many cats (though some do scratch)
Because these signs overlap with allergies, mites and other infections, ringworm can't be diagnosed by appearance alone — testing is needed.
Diagnosis and treatment
Your vet may use several methods, since no single test is perfect:
| Test | What it does |
|---|---|
| Ultraviolet (Wood's) lamp | Some strains glow; a useful screen but not definitive |
| Fungal culture or PCR | The reliable way to confirm and identify the fungus |
| Microscopic exam of hairs | Can show fungal spores on the hair shaft |
Treatment usually combines oral antifungal medication, topical antifungal creams or dips/rinses, and thorough environmental cleaning. It's a marathon, not a sprint — treatment often runs for several weeks and should continue until follow-up cultures confirm the cat is clear, because stopping early lets it come back.
Cleaning the environment and tracking recovery
Because spores linger in the home, decontamination is half the battle: wash bedding, vacuum thoroughly and often (discarding the bag or emptying the canister outside), disinfect hard surfaces, and limit the cat to easy-to-clean areas during treatment. Recovery is judged by repeat cultures rather than by how the skin looks, since lesions can heal while the cat is still contagious. Tracking the treatment timeline — medication doses, when lesions appear or heal, and recheck results — helps you stay consistent through a long course and confirm the infection is truly gone before you relax the cleaning routine.
Stay on top of a long treatment course
Tavi lets you log medications, skin changes and recheck results over time, so you can keep a stubborn ringworm treatment on track and confirm it's truly cleared. Free for your first pet.
Frequently asked questions
Is ringworm in cats contagious to humans?
Yes, ringworm is zoonotic, meaning it can spread from cats to people, and also to other pets. Children, elderly people and those with weakened immune systems are more susceptible. Wash your hands after handling an infected cat and see a doctor if you develop a red, ring-shaped, itchy patch.
How long does ringworm last in cats?
With proper treatment it often takes several weeks to clear, and sometimes longer. Treatment should continue until follow-up fungal cultures confirm the cat is free of infection, because skin can look healed while the cat is still contagious. Stopping too early is a common reason it comes back.
What does ringworm look like on a cat?
Classically it causes circular patches of hair loss with scaly or crusty skin, often on the face, ear tips and paws, sometimes with broken stubbly hairs. Itching may be mild or absent. Because it mimics other skin conditions, a vet needs to confirm it with testing rather than appearance alone.
How do you get rid of ringworm in the house?
Decontamination is essential: wash bedding, vacuum thoroughly and frequently, disinfect hard surfaces, and confine the cat to easy-to-clean areas during treatment. Spores can survive for months in the environment, so cleaning must happen alongside treating the cat, or reinfection is likely.
Can a cat have ringworm without symptoms?
Yes. Some cats, particularly long-haired ones, can carry and shed the fungus while showing little or no visible signs. These carriers can still infect other pets and people. That's why cats in multi-pet homes or catteries are sometimes screened even when they look healthy.
Tavi's guides are informational and not a substitute for professional veterinary advice, diagnosis or treatment. When in doubt, call your veterinarian. Sources: Cornell University Feline Health Center; Merck Veterinary Manual; VCA Animal Hospitals; Centers for Disease Control and Prevention (CDC)