Ringworm is a common, contagious skin infection in cats, and one that people can catch too. Despite its name, it has nothing to do with worms: it’s caused by a fungus. Here’s how to recognize ringworm, why it needs a vet’s diagnosis and treatment, and how to protect your family and your home.
What Is Ringworm?
Ringworm (dermatophytosis) is a fungal infection of the skin, hair and sometimes the claws. In cats, it’s most often caused by a fungus called Microsporum canis. The fungus produces tiny spores, which spread easily and can survive in the environment, on bedding, furniture, carpets and grooming tools, for many months.
Cats catch ringworm through direct contact with an infected animal or with contaminated objects. Some cats carry the spores without showing any signs, but can still spread them.
Which Cats Are Most at Risk?
- kittens and young cats;
- senior cats and cats with weakened immune systems or other illnesses;
- long-haired breeds, such as Persians;
- cats from shelters, catteries and multi-cat homes;
- stressed or poorly nourished cats.
Signs of Ringworm
- round or irregular patches of hair loss, often on the head, ears, face or front legs;
- broken hairs and a “moth-eaten” look to the coat;
- dry, scaly or crusty skin;
- redness around the patches;
- sometimes itching, although many cats aren’t itchy;
- brittle or misshapen claws, in some cases.
These signs can look very similar to other skin problems, such as allergies, fleas or mites. That’s why you shouldn’t try to diagnose or treat it yourself.
Diagnosis
Your vet can diagnose ringworm with:
- an examination under a special ultraviolet lamp (a Wood’s lamp), under which some types of ringworm glow green, although not all do;
- a fungal culture, in which hairs or skin scrapings are tested to see if the fungus grows;
- a PCR test or microscopic examination of hairs.
Treatment
Ringworm can clear up on its own in some healthy cats, but this can take months, and the cat will keep spreading spores in the meantime. Treatment speeds up recovery and protects other pets and people. Your vet will decide on the best treatment, which often includes:
- oral antifungal medication, given for several weeks;
- medicated baths, dips or rinses to kill spores on the coat;
- clipping the fur in some long-haired cats, to make treatment more effective;
- repeat tests to confirm the infection has cleared. Treatment usually continues until your cat has had negative tests, not just until the patches look better.
Don’t use home remedies or human antifungal products on your cat without your vet’s advice. Products such as iodine, vinegar, tea tree oil and other essential oils can burn a cat’s skin or be toxic if licked, and they won’t clear the infection.
Cleaning Your Home
Because spores survive for a long time, cleaning your home is an important part of treatment:
- keep your cat in one easy-to-clean room during treatment, if possible;
- vacuum floors and furniture often, and throw away the vacuum bag or empty the canister outside;
- wash bedding, blankets and soft toys on a hot cycle, and throw away items that can’t be washed;
- clean hard surfaces regularly. Ask your vet which disinfectant to use and how, because some products aren’t safe around cats;
- clean or replace grooming tools, carriers and cat trees.
Can People Catch Ringworm from Cats?
Yes. Ringworm is a zoonosis, meaning it can spread from animals to people. In people, it usually looks like a red, itchy, ring-shaped rash on the skin. Children, older people and people with weakened immune systems are more likely to catch it. To reduce the risk:
- wear gloves when handling an infected cat or giving treatment, and wash your hands thoroughly afterward;
- limit cuddling and don’t let an infected cat sleep on your bed until your vet says it’s no longer contagious;
- keep infected cats away from young children and other pets as much as possible;
- see your doctor if you notice a rash. Ringworm in people is usually easy to treat.
Prevention
- check new cats and kittens for skin problems, and keep them separate until a vet has examined them;
- don’t share grooming tools and bedding between cats from different homes;
- keep your cat healthy with a balanced diet, regular vet checkups and parasite control.
If you notice any patches of hair loss or skin changes on your cat, see your vet. Read more about hair loss in cats.
