Dermatophytosis

Overview

Ringworm is poorly named as it is not a worm at all. Rather it is known in medical circles as dermathophytosis, a skin and scalp infection caused by several different kinds of fungi known collectively as tinea. Examples of tinea are on your body (tinea corporis), scalp (tinea capitis), groin (tinea cruris, or jock itch), feet (tinea pedis, or athlete's foot) and nails (tinea unguium).

An estimated 20 percent of us will develop ringworm at some time in our lives. It is especially common among children as it can quickly spread in a classroom or daycare setting.

Causes

From its name, you'd think ringworm was caused by a worm infestation. Hundreds of years ago, that was the belief but we now know that it is actually a fungal infection. This particular fungus makes a breeding ground of dead cells in the outer layer of your skin which is rich in keratin, a tough, insoluble protein that it feeds on. When our bodies try to fight off the infection, the area becomes inflamed.

Ringworm is contagious and can be passed from one person to another by direct skin-to-skin contact or by contact with contaminated items such as combs, unwashed clothing, and shower or pool surfaces. You can also catch it from pets, especially cats.

Some people are more at risk than others, including:

  • children in daycare
  • swimmers and other athletes
  • people who are obese
  • anyone with weakened immune systems
  • people who work with animals

Symptoms 

While similar in many respects, symptoms of ringworm vary, depending on the site of the infection:

  • Tinea corporis or ringworm of the body causes red, scaly round patches with a raised border (like a ring). The skin is itchy.
  • Tinea cruris, or jock itch, causes similar patches but they appear near the groin. They sometimes burn as well as itch.
  • If you have tinea pedis, or athlete's foot, in addition to red scales, you will also likely have cracked skin and your feet may smell as well as itch and burn.
  • Tinea capitis, or ringworm of the scalp may at first appear to be just dandruff. However, it will leave your hair brittle and as the damaged hair falls out, you'll notice scaly bald patches.
  • With tinea unguium, or ringworm of the nails, the affected nails become discoloured and brittle.

Treatment

Ringworm can be cleared up over the course of 3 to 4 weeks with medication. Over-the-counter powders, ointments and creams can be spread on the infected area. If the infection is severe or persists, your doctor may prescribe an anti-fungal drug that you swallow.

Prevention

Ringworm can be prevented by taking some simple precautions including:
  • Always keep your skin and feet clean and dry; wear something on your feet in locker rooms and around pools.
  • Never share personal care items such as towels or combs.
  • Do not touch a dog or cat that appears to have bald spots.