Ringworm (tinea, dermatophytosis)
What are ringworm and other fungal skin infections?
Ringworm (dermatophytosis) is a common fungal infection of hair, skin, or nails. Ringworm is caused by fungi (not a worm). Examples of ringworm infections include:
- Infections of the skin or most parts of the body (tinea corporis),
- Infections of the feet (tenia pedis, or athlete’s foot),
- Infections of the groin (tenia cruris, or jock itch),
- Infections of the scalp (tenia capitis),
- Infections of the nails (onychomycosis).
These types of infections are very common and can affect anyone. People with weakened immune systems may be at higher risk of infection and may have problems figthing off a ringworm infection. These infections typically have no long-term health consequences and can be effectively treated. Ringworm sometimes causes outbreaks in schools and child care centers.
Signs and symptoms
- On the skin, ringworm usually causes an itchy, red, ring-shaped rash. There may be a clear scaly area inside the ring, scattered bumps inside the ring, or overlapping rings.
- Ringworm of the feet causes red, swollen, peeling, itchy skin between the toes.
- Ringworm of the groin causes itchy, scaly, red spots on the inner thigh.
- Ringworm of the hair causes a scaly, itchy, circular, red bald spot and hair loss.
- Nail infections (onychomycosis) may cause nails to change colors, become thick, and break easily. Infections of the toenails are more common than infections of the fingernails. People with diabetes are at increased risk of fungal nail infections and secondary bacterial infections of the skin.
Incubation period
Between four and 14 days.
Contagious period and spread
Ringworm is very common and can be spread by:
- Skin-to-skin contact with people or animals with the infection,
- Shared objects (e.g., towels, bed sheets),
- Shared surfaces (e.g., locker room floors).
Risk factors include:
- Use of public showers or locker rooms without protective footwear,
- Participating in contact sports like wrestling,
- Wearing tight shoes adn socks,
- Excessive sweating,
- Close contact with animals.
The infection can be spread to others as long as the rash is present on the skin.
Public health reporting requirements
Individual cases are not reportable.
Suspected outbreaks of all types (including fungal infections/ringworm) are reportable to state or local public health.
Control of spread
- Ensure all people and pets with infection are treated.
- Encourage good hygiene and handwashing.
- The child/student should not share personal items, such as clothing, hairbrushes, and hats, with other people.
- The spores of this fungus on surfaces can be killed with common disinfectants like diluted chlorine bleach (¼ cup per gallon of water), benzalkonium chloride, or strong detergents. See Disease Prevention: The Facility Environment for sanitizing and disinfecting guidelines.
- Skin checks for close school and household contacts and pets. during weigh-in for wrestlers
Treatment
Fungal infections, including ringworm, can be treated with antifungal medicine that can be taken in tablet or liquid form by mouth, or as a topical cream applied directly to the affected area. The particular medication used and duration of treatment is based on the severity and location of the infection. Some treatments require a prescription by a health care provider, and some topical creams can be purchased over-the-counter.
A more severe type of ringworm has been spreading in parts of the world. There have been some cases in the U.S.. These infections cannot always be treated by antifungal usually used for ringworm. A child should see their doctor if the ringworm infection is severe, widespread, or does not go away with treatment.
Avoid creams containing steroids.
Prevention
- Keep skin clean and dry.
- Wear shoes that allow air to circulate freely around the feet.
- Wear protective footwear in areas like public showers or locker rooms.
- Wash hands after touching pets.
- Do not share clothing, towels, sheets, or other personal items.
- Change socks and underwear every day.
- Keep fingernails and toenails short and clean.
Athletes can help prevent ringworm by:
- Taking a shower right after practice, matches or games
- Keeping sports gear clean
- Not sharing sports gear (helmets, etc.) with other players
- Wearing shoes or sandals in locker rooms and public showers
Exclusion
Ringworm: Exclude children/students or staff with ringworm infection from the end of the program or school day until after treatment has started. Until the end of the program or school day, avoid any activity involving skin contact.
Children/students with infections of exposed skin may require exclusion from some athletic activities while under treatment until the infection is controlled (e.g., swimming, wrestling).
Role of teachers, caregivers, and family
- Report the infection to the staff member designated by the child care program or school for decision-making and action related to care of ill children. That person, in turn, alerts possibly exposed family and staff members to watch for symptoms.
- Complete medication as prescribed by your health care professional.