Ringworm fungus can survive on clothing and other fabrics for months. Under ideal conditions, the spore form of the fungus (tiny dormant particles shed from infected skin) can remain viable for much longer. Research on Trichophyton species, the most common group behind ringworm infections, has found that their spores can stay stable in the environment for up to five years. That doesn’t mean every contaminated shirt is dangerous for years, but it does mean tossing worn clothes in a hamper and forgetting about them won’t solve the problem.
Why the Fungus Lasts So Long
Ringworm isn’t actually a worm. It’s a type of fungus called a dermatophyte that feeds on keratin, the protein found in skin, hair, and nails. When the fungus reproduces, it breaks apart into tiny fragments called arthroconidia. These spores are built to survive. They’re lightweight, resistant to drying out, and can cling to fabric fibers, waiting for contact with warm, moist skin to start growing again.
The survival timeline depends heavily on conditions. A damp towel left balled up in a gym bag creates a warm, humid microenvironment where spores not only survive but can potentially multiply. Dry, well-ventilated conditions are less hospitable, but even then the spores don’t die quickly. Storing dirty laundry in a hamper or humid environment encourages the growth of fungi and bacteria alike, extending the window of risk.
How Ringworm Spreads Through Clothing
Any fabric that touched an active ringworm infection can carry spores: shirts, socks, underwear, towels, bed sheets, hats, and even upholstered furniture. The fungus sheds onto these surfaces during normal wear and use, and anyone who handles or wears the contaminated item can pick up the infection. Shared towels and shared laundry baskets are especially common routes of household transmission.
You don’t need prolonged contact. Simply pulling on a contaminated shirt or drying off with an infected towel gives spores access to your skin. If that skin is warm and slightly damp (after a shower, during exercise, or in skin folds), conditions are ideal for the fungus to take hold. People with minor skin breaks, weakened immune systems, or those who sweat heavily are at higher risk.
Washing Contaminated Clothes
A normal cold or warm wash cycle is not enough to kill ringworm. Research has shown that Trichophyton rubrum, one of the most common ringworm species, can survive a 30°C (86°F) wash. That’s the typical “cold” or “warm” setting on most machines. Washing at 60°C (140°F), however, eliminated the fungus completely in the same study. If your machine has a “hot” or “sanitize” setting, use it for any laundry that may be contaminated.
Not all fabrics tolerate hot water, though. For delicates or items that can’t handle 60°C, adding a disinfecting laundry additive can help. Chlorine bleach is effective against dermatophytes on white or bleach-safe fabrics. For colors, look for a laundry sanitizer product designed to work at lower temperatures.
Drying Matters Too
Heat from the dryer adds a second line of defense. Dry contaminated laundry separately from clean clothes, using the highest heat setting the fabric allows. Clean the lint filter after every load, since fungal spores can collect there and potentially transfer to the next batch of laundry. If you’re air-drying, direct sunlight helps, but it’s less reliable than sustained dryer heat.
Preventing Reinfection at Home
Killing the fungus on one load of laundry doesn’t help much if spores are still circulating through the household. A few practical steps reduce that risk significantly.
- Separate contaminated laundry immediately. Don’t let it sit in a shared hamper. Use a dedicated bag or bin, and wash it as soon as possible.
- Wash bedding and towels frequently. During an active infection, change sheets and towels daily if you can, and wash them on hot.
- Don’t share personal items. Towels, clothing, hairbrushes, and hats should stay with one person until the infection clears.
- Wipe down the washing machine. Run an empty hot cycle or wipe the drum after laundering contaminated items, especially if your next load will be washed at a lower temperature.
- Clean the lint trap. Spores trapped in dryer lint can recontaminate clean laundry in subsequent loads.
How Long Clothes Stay Contagious
A contaminated garment remains contagious for as long as viable spores are present on it, which can be months under normal household conditions. There’s no point at which clothes “air out” and become safe on their own. The only reliable way to eliminate the risk is heat: a hot wash, a hot dryer cycle, or both. Until that happens, treat any clothing or fabric that contacted an active infection as potentially contagious, even if weeks have passed since it was last worn.