If you’ve been caring for cat colonies, barn cats, or fostering kittens, you’ve probably gotten some experience with ringworm by now. Ringworm and cats are often linked together in very negative ways.
There are many causes of ringworm and cats are only one of them. Cats are often blamed for it in people, horses, and other pets.
Ringworm sounds super scary, but it really isn’t. It is a common issue in outdoor cats, shelters, and especially kittens. So let’s learn what ringworm actually is, the causes of it, symptoms of it in cats, and the treatment options available.
Disclaimer: I am not a veterinarian. This article is for educational purposes only and should not be used to diagnose or treat any illness or disease. Please discuss any health issues regarding your pets or cat colony with your veterinarian.
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What is Ringworm?
Ringworm is a fungal infection of the skin. It is not a worm or parasite. It is called ringworm because it can cause a circular red rash that is shaped like a ring. Not all infections will cause the circular rash, though.
Depending upon where the rash is located, it often has different names. Ringworm of the feet is often called athlete’s foot. Ringworm in the groin is called jock itch. Your fingernails and toenails can contract this fungal infection too and it won’t be called ringworm. But it is the same thing. If you want a full list of various names for these fungal infections, you can find them here.
About 40 different species of fungi can cause ringworm. You heard that right. FORTY DIFFERENT KINDS! The most common class of fungi that cause skin infections are called Dermatophytes. These fungi obtain nutrients from the keratinized material of humans and animals, such as nails, hair, feathers, etc. This is why they infect the outer layer of the skin. But let’s not get too technical.
Depending upon where the infection is located, it could be called ringworm or it could be called athlete’s foot. That said, in cats, it’s just called ringworm no matter where it’s located.
Causes of Ringworm in Cats
Fungi thrive in moist, warm environments and common sources of fungal skin infections include locker rooms, tanning beds, skin folds, swimming pools, exercise machines, and even your garden soil!
Risk factors for contracting ringworm include using public showers, contact sports such as wrestling, excessive sweating, contact with animals, obesity, poor immune function, and poor hygiene. Children (and kittens) as well as those with a depressed immune system are most often infected.
Some species of dermatophytes are species-specific and only infect that species. Some species can infect a wide variety of animals and humans.
In cats, the species that is most often the cause of ringworm is Microsporum canis, which can infect cats and sometimes dogs, horses, and people. In fact, 98% of ringworm cases in cats are caused by this one species, according to the Merck Veterinary Manual. Other types of ringworm, such as the species that live in soil, can also affect cats and people.
Ringworm in cats can often be asymptomatic, which results in a carrier condition. This simply means that a cat can spread ringworm but has no symptoms of an infection. The cause of ringworm in cats is contact with infected animals, objects, or environments.
That said, ringworm might be contagious but it isn’t THAT contagious. It is not uncommon to only have one or two cats or kittens infected, while the rest of the household or colony shows no symptoms at all. That is because most adults (both human and cat) are often resistant to infection. But prolonged exposure increases the risk of infection in healthy adults.
Symptoms of Feline Ringworm
The incubation period between exposure to ringworm and the development of symptoms is 7-21 days. This means if you pet a stray cat yesterday and have ringworm today, then that is not the most likely cause of your infection.
The most common symptom of ringworm in cats is no symptoms at all! But every cat is different and may or may not have one or many of the following signs of ringworm.
- No symptoms
- Hair loss
- Scaly, flaky skin patches.
- Small itchy bumps on the skin
- Broken hairs around the lesions.
- Open sores
- Scaly claws, malformed claws
- Dandruff in the cat’s fur
- Ringlike lesions on your cat’s skin
- Small, thickened patches of skin
Kittens are most often infected as their immune systems aren’t fully developed. Kittens are also more likely to have more severe types of ringworm infections as well. Elderly cats and cats with a weakened immune system are often more likely to get ringworm.
How Do You Diagnose Ringworm in a Cat?
Only a licensed veterinarian can definitively diagnose ringworm in your pet or feral cats. The most reliable way a veterinarian uses to diagnose ringworm is by sending samples to a lab, but that can take a couple of weeks. Faster, less accurate ways exist, such as using a UV lamp to check for glowing strands of hair (this occurs about half of the time in ringworm infections) or by looking at skin scrapings under a microscope.
That said, if you have a lot of experience with cat colonies, kitten fostering, and animal rescue and animal shelters, then you might be able to make an educated guess based on experience.
Treatment for Ringworm in Cats
Here’s some good news: Ringworm SOUNDS scary but it really isn’t! Ringworm is usually mild and self-limiting in adult cats. That means it’s a minor issue and will often resolve on its own. Most adult cats and humans are often resistant to infection so the chances of you catching ringworm from your infected cat is very low, even if you weren’t being careful. And if you or your cat do catch ringworm, it’s super easy to treat. It just takes time.
Sometimes no treatment is necessary. Most mild ringworm infections in cats will heal on their own due to a cat’s immune system. That’s excellent news for us feral cat caretakers! I don’t bring in my barn cats or cat colony for ringworm unless it is making the cat miserable or it is severe or persistent. The trauma of treating an unsocialized cat for ringworm and bringing him into the vet is more harmful than the ringworm infection itself.
That said, treating your pets and yourself can help reduce the length of infection and help stop it from spreading to other animals. And ALWAYS treat kittens who are infected. They do not have strong immune systems.
It is always best to isolate the infected cat from others to help stop the spread of ringworm, if possible. The environment (i.e. the house) must also be treated if you want to completely cure the infection.
The most common way to treat ringworm is to use topical antifungal medications. This may include creams, medicated antifungal shampoos, or a lime sulfur dip. Or a combination of all of these. Always follow your veterinarian’s instructions.
If the cat is a long-haired variety, your vet may suggest clipping the fur to help make treating the cat easier.
For more severe infections, your veterinarian may prescribe an oral antifungal medication as well as those topical options listed above. (I have included examples in the links, but what your vet recommends might be different!)
Common Ringworm Treatments
- Lime Sulfur Dip – which is smelly and not fun, but only needs to be done about once or twice a week.
- Antifungal Shampoo – this may or may not be a specific kind recommended by your vet.
- Topical antifungal treatment – this may or may not be a prescription from your vet.
- Oral antifungal medications – this WILL be a prescription from your vet.
- Environmental cleaning – using a diluted bleach solution or other disinfectants to clean the environment where an infected animal has been.
How to Prevent Ringworm
Despite the fact ringworm is not seriously infectious nor is it usually a huge health issue, it’s always a good idea to do what you can to prevent you and your cats from getting ringworm in the first place. Ringworm might not be scary, but it can take weeks to be rid of it and it can cause uncomfortable itching and unsightly lesions. Another big reason to try to prevent ringworm is so that you don’t spread it to a more vulnerable person or animal who may get more severe symptoms and who may have problems being cured of infection, such as immune-compromised individuals and pets.
So how do you prevent ringworm?
- Good hygiene – keep your skin clean and dry, especially sweaty areas such as the groin, feet, folds of skin, etc.
- Wear shoes that allow your feet to ‘breathe’.
- Wash hands frequently, especially after touching free-roaming cats.
- Wear gloves and long sleeves if you must handle a cat or other pet with ringworm.
- Always wash hands or apply hand sanitizer after petting strange dogs, cats, or other animals.
- Don’t walk barefoot, especially in public shower areas such as at swimming pools and gyms.
- Always disinfect gym equipment before use.
- If you participate in contact sports, shower immediately after a match or practice session, and don’t share equipment.
- Clip your fingernails and toenails short and keep them clean.
- Don’t share personal items such as towels.
- Vacuum the floor regularly to remove dried skin and hair, wash pet bedding regularly, and regular disinfection of pet living quarters.
- Do NOT handle animals with ringworm if you’re immune system is compromised (such as due to HIV/AIDS or are undergoing cancer treatments, for example.)
- Keep your pet cat indoors and don’t let him have contact with strays or feral cats.
Ringworm and Cats: Other Important Info
Ringworm can stay infective in your home and other environments for up to 18 months. That’s a year and a half!
If you have a cat with ringworm, always quarantine them to one room that is easy to disinfect. It’s much harder to keep an entire house clean and disinfected than it is to regularly clean and disinfect one room.
Always see your veterinarian if you have concerns about your cat’s health. Ringworm is NOT the only skin issue that causes hair loss and lesions. Appearance alone is not enough of an indication of ringworm.
Cats are not the only source of ringworm. In fact, they’re only ONE source of ringworm. Poor hygiene actually causes a lot more fungal infections that cats do.
Did you know? Cats that have poor grooming habits are at increased risk for contracting a ringworm infection than one who grooms himself regularly. Poor hygiene issues affect cats too!
Remember, it’s also not a huge deal for most cats or people. It’s a simple, easily treated infection that can be cured with the right treatment.
What’s your experience with this dreaded fungus? Tell me below by leaving a comment!