Ringworm is a highly contagious rash caused by exposure to the live spores of certain types of fungi. These fungi tend to live in hot and humid climates, and their spores thrive on humans in areas that replicate that environment, such as the groin, the feet, or the scalp. It is sometimes given other names depending on the affected area. Ringworm affecting the foot is referred to as “athlete’s foot”. If it is affecting the groin area, it might be called “jock itch”.
The medical diagnosis for ringworm includes tinea capitis (the scalp), tinea pedis (the foot), tinea cruris (the groin) or tinea corporis (the body). When the patient develops the ringworm rash, it usually forms in patches that are red and scaly. These lesions may be raised like, other forms of dermatitis, but then spreads into a rough circle. The interior of the circle may have small red bumps that itch. Patients may develop several big rings around the affected area.
The condition is called ringworm because of the pattern that the rash takes on the body, starting with a centrally infected area and spreading outward in rings. The fungi involved in ringworm attach to keratin in the skin, nails or scalp and spread from there. The rash may run and manufacture pus, causing a crusty surface on the affected skin.
Ringworm may be spread through several different methods. These include:
Ringworm is not especially dangerous but can be itchy and inconvenient. Left untreated, it can take months to go away. Typically it responds well to over the counter anti-fungal medications in cream or ointment form. If the ringworm is persistent or does not respond to topical medications, a doctor may prescribe oral anti-fungal medication. Ringworm can be more serious when the patient has a compromised immune system, particularly in the case of HIV/AIDS. These patients may have difficulty getting rid of ringworm.
Standard treatments for ringworm vary depending on where the rash appears on the body and how much surface area the rash occupies. In general, ringworm on skin responds well to topical anti-fungal cream or lotion applied several times a day for a course of 10 to 14 days. If the rash is particularly widespread, a prescription medication may be required with a higher concentration of medication. As the rash abates, it may dry out and become scaly before the skin begins to clear. For ringworm that occurs in the form of athlete's foot, spray or cream with anti-fungal medicine is usually indicated. For jock itch, best practice indicates the use of anti-fungal spray or powder usually twice a day for two weeks. When ringworm appears in the scalp, the prescription medication griseofulvin is the standard treatment. Prescription medication is also necessary when the ringworm infection occurs in the nails, whether on the hand or the foot. This form of ringworm takes the longest to clear up given how slowly nails grow.
How long is ringworm contagious? This depends on how long the live spores are actually present in the rash. As long as the spores are living, the patient is contagious and may spread the rash to others through skin to skin contact or by depositing those spores on an inert surface such as a towel or clothing. This surface may now cause infection in someone else as long as those spores stay alive. If the inert surface is in a warm, damp environment such as a shower or bathroom, those spores could live for several weeks. The infection may also be spread while the spores are still in the incubation stage, and the rash and symptoms have yet to manifest in the patient. Incubation periods can last anywhere from a few days to two weeks.
Typically within 24 to 48 hours after a patient begins treatment with anti-fungal medication, he or she is no longer contagious because the live spores are destroyed. However, in some cases, the patient may remain contagious. This is particularly true in patients who suffer from other conditions that affect their immune system, such as AIDS, or autoimmune disorders like lupus. Normal courses of treatment may not destroy the live spores, meaning the patient continues to suffer both symptoms and spread of the infection but also remain infectious.
Prevention of ringworm is difficult. Some best practices center around personal hygiene. When using public pools, showers or bathrooms, never go barefoot. Cotton underwear is a better choice than synthetic materials that do not breathe as well. Patients should avoid sharing items that may carry the spores. This would include things like towels or clothing. Clean bedding can also prevent the spread of ringworm. Thorough drying after bathing is important also. Another key prevention is avoiding anyone with an active ringworm infection. Also, wearing loose-fitting clothing can help prevent the incubation of the fungus that causes ringworm.