Ringworm spreads through direct skin contact with an infected person, animal, or contaminated surface, and the fungal spores that cause it can survive in the environment for months to years. Avoiding it comes down to three things: keeping your skin clean and dry, not sharing personal items, and knowing the common sources of exposure so you can reduce contact with them.
How Ringworm Actually Spreads
Despite the name, ringworm has nothing to do with worms. It’s a fungal infection of the skin caused by a group of fungi called dermatophytes. These fungi feed on keratin, the protein in your skin, hair, and nails, and they thrive in warm, moist environments.
The most common route is skin-to-skin contact with an infected person. But you can also pick it up from pets (especially cats and dogs), contaminated objects like hairbrushes or towels, and surfaces like locker room floors or wrestling mats. Fungal spores shed from infected animals can remain infectious in the environment for several years, particularly in humid conditions. After exposure, symptoms typically appear within 4 to 14 days.
Animals you might not suspect can carry the fungus too. Horses, cattle, and even wild animals that wander into yards or neighborhoods are potential sources. Hunting dogs that come into contact with wildlife can pick up the infection and pass it to their owners.
Keep Skin Clean and Dry After Exposure
The fungus needs moisture to establish itself on your skin, so the single most effective daily habit is washing and thoroughly drying your skin after situations where you might have been exposed. That means after workouts, after using shared gym equipment, after playing with animals, and after walking barefoot in communal areas like pool decks or locker rooms.
Wear shower shoes or sandals in shared showers, locker rooms, and pool areas. These surfaces stay warm and damp, which is exactly what the fungus needs to survive between hosts. Change out of sweaty clothes promptly after exercising. Synthetic moisture-wicking fabrics that keep skin drier are a better choice than cotton for workouts, since cotton holds moisture against the skin longer.
Don’t Share Personal Items
The fungus lingers on objects that touch skin and hair. Combs, brushes, hats, towels, razors, and clothing are all potential carriers. An infected electric razor caused at least one documented hospital outbreak. The rule is simple: keep personal grooming items personal.
This applies at home too. If someone in your household has ringworm, give them their own towel set, washcloth, and comb. Don’t share bedding until the infection clears. The same goes for sports gear, helmets, and headbands.
How to Clean Contaminated Laundry
If you’re dealing with potentially contaminated towels, bedding, or clothing, the good news is that you don’t need boiling water or bleach. Research published in the Journal of Feline Medicine and Surgery found that washing contaminated fabric twice in cold water on a long cycle (at least 14 minutes of wash time per cycle) completely eliminated fungal spores from terry cloth towels and denim. The mechanical agitation of the washing machine did the heavy lifting, and adding bleach provided no additional benefit.
The key detail: don’t overload the machine. The spores are removed by the physical tumbling and rinsing action, so the clothes need room to move freely. Two normal-load washes with a standard cycle length will do the job.
Protecting Yourself From Pets
Cats are the most common animal source of ringworm in humans, partly because their intensive grooming habits scatter fungal spores and infected hairs throughout their environment. A cat with ringworm may have patchy hair loss, scaly skin, or broken hairs, but some cats carry the fungus without showing obvious symptoms.
If your pet develops a rash, bald patches, or crusty skin, the CDC recommends these steps:
- Get veterinary treatment immediately. The longer an infected pet goes untreated, the more spores accumulate in your home.
- Have other pets checked. Ringworm spreads between animals in the same household.
- Wear gloves and long sleeves when handling an infected pet.
- Wash your hands with soap and running water after any contact.
- Vacuum frequently, especially areas where the pet spends time, to remove shed hairs and spores.
- Disinfect hard surfaces and wash pet bedding using the two-wash method described above.
People who work closely with animals face higher risk. Veterinarians, stable workers, riders, and farmers who handle cattle are all more frequently exposed. If you work with animals regularly, wearing long sleeves and washing exposed skin after handling them significantly reduces your chances of infection.
Prevention for Athletes and Contact Sports
Ringworm outbreaks are notoriously common in wrestling, jiu-jitsu, and other sports involving prolonged skin-to-skin contact. A study on collegiate wrestlers found that implementing a comprehensive prevention protocol, including daily skin checks, dropped ringworm cases from 10 per season to just 1.
If you participate in contact sports, shower immediately after practice or competition. Inspect your skin regularly for any new red, scaly, or ring-shaped patches, and report them before they spread to teammates. Training mats and shared equipment should be disinfected between sessions. Many wrestling programs now require pre-competition skin checks for exactly this reason.
Wearing clean practice gear for every session matters more than most athletes realize. Reusing a sweaty rashguard or singlet from the day before gives any fungal spores picked up during training a warm, moist environment to multiply in before your next skin-to-skin contact.
What to Do if You’ve Been Exposed
If you know you’ve had contact with a person, animal, or surface that’s infected, wash the area with soap and water as soon as possible. There’s a window of 4 to 14 days before symptoms appear, so you won’t know right away whether the fungus took hold. During that time, watch for a red, itchy, slightly raised patch of skin that may develop into the classic ring shape with clearer skin in the center.
Catching it early makes a real difference. Small, localized ringworm infections on the body typically respond well to over-the-counter antifungal creams applied consistently for two to four weeks. Scalp ringworm is harder to treat and usually requires oral medication, which is one more reason to avoid sharing hair tools and hats.