Ringworm in Cats and Dogs: How It Spreads and Can People Catch It?

Good to know: ringworm is common. In healthy pets and people it is rarely serious, and it is treatable [3][6].

Ringworm is a fungal skin infection that affects both cats and dogs, and it can pass between pets and people [1][3]. A vet for your pet and a doctor for your family are the right people to check it [3][4].

What is ringworm?

• A fungal infection of the skin, hair and claws. Despite the name, there is no worm involved [1][5].
• It is caused by fungi that feed on keratin, the protein in hair, skin and nails [5].
• In both cats and dogs, the large majority of cases come from one fungus, Microsporum canis [3][6][9].
• Cornell's Feline Health Center lists it among the most common skin problems in cats worldwide [5].

Can people catch ringworm from a cat or dog?

Yes. The same fungus can pass from an infected cat or dog to a person, and from a person back to a pet [1][3][6]. So it is best treated as a whole-household matter, not just a pet problem.

A published report from the Aseer region of Saudi Arabia described members of two related families, including children, who developed ringworm after contact with cats [8]. In people it is usually mild and curable [1][6].

How does it spread?

• Direct contact with an infected cat's or dog's fur or skin [3][4][5][6].
• Shared things: bedding, brushes, grooming tools, carriers, furniture and carpets [3][4][6][9].
• The fungus makes hardy spores. In a dry setting they can last up to about a year, depending on conditions and cleaning [6].

Contact does not always lead to infection. Small skin injuries make it easier for spores to take hold, while a pet's own grooming and immune system can often clear a light exposure [3][5].

Which pets are most at risk?

Cats and dogs:

• Young animals under about a year old, and older animals [3][9].
• Pets from shelters, catteries, boarding or breeding settings, or crowded multi-pet homes [3][6].
• Stress, and skin damaged by scratches, flea bites or too much moisture [6][9].

Cats: longhaired cats, because spores get trapped in long fur. Persian cats are described as more prone to severe or long-lasting infection [4].

Dogs: young dogs, dogs that roam or hunt, and dogs in warm environments [3].

Can an indoor cat get ringworm?

It can. Spores travel on bedding, brushes and other objects, and the fungus can pass from people to pets too [1][3][4][6]. New pets from shelters or with an unknown background are more likely to carry it [4][6].

What does ringworm look like on a pet?

• Roughly round patches of hair loss, often on the head, ears, legs or paws [3][4][5][6].
• Broken, stubbly hairs, with scaling, crusting or flaking skin [3][4][5][6].
• Sometimes a reddish ring around a clearer centre [3][4][5][6].
• Brittle claws or claws that look different [5].
• New scratching, over-grooming or dandruff [5].

When should I see a vet?

See a licensed vet promptly if your cat or dog has any of the signs above [1]. Take extra care with a kitten, a puppy, or a pet that has recently met a stray, a shelter animal or another pet with a skin problem [3][6][9].

There is no home remedy that reliably clears ringworm. Your vet confirms whether it is ringworm and decides how to manage it [3][4].

When should a family member see a doctor?

In people, ringworm often looks like an itchy, scaly, ring-shaped patch. It can look red on lighter skin and grey or brown on darker skin [1].

If someone at home, especially a child, has a new or spreading rash while a pet has a skin problem, they should see their own doctor [1][8]. People with a weaker immune system can find it harder to clear, so a doctor's check matters more for them [1][3][7].

How can I protect my pets and family?

• Until a vet has checked a pet with a suspicious patch, limit shared bedding, brushes and close cuddling [1][2][4].
• Everyone, especially children, should wash their hands after touching pets [1][2].
• Wash pet bedding and clean carriers and grooming tools regularly to reduce spores at home [6].
• Book a vet check-up for any newly adopted pet, especially from a shelter or the street [4][6].

FAQ

Is ringworm a worm?

No. It is a fungal infection of the skin, hair and claws [1][5].

Does ringworm pass between cats and dogs in the same house?

Yes, it can. The same fungus is the main cause in both cats and dogs, and it spreads through contact and shared items [3][6][9].

Can a pet spread ringworm without showing signs?

It can happen. Shelters and crowded homes tend to have more animals that carry the fungus, which is why new pets benefit from a vet check [3][4][6][9].

Is ringworm the same as mange?

No. Ringworm is a fungal infection [1][5]. Other skin problems can look similar, so a vet is the right person to check [3].

Will ringworm go away on its own?

Don't wait to find out. There is no reliable home remedy, and the CDC advises taking a pet to the vet right away if ringworm is suspected [1][3][4].