Ringworm of the Scalp or Beard - Cause
Ringworm infection is caused by a
fungus. Fungi that cause
ringworm live and multiply on the upper layer of the
skin and on the hair. Ringworm is not caused by a worm
or other parasite.
The medical term for fungal infections is
tinea, followed by a word that describes the location of infection. For
example, tinea capitis is ringworm of the scalp, and tinea barbae is ringworm
of the beard.
Ringworm of the scalp is most commonly caused by
the fungus Trichophyton tonsurans, which is spread from
one person to another. This fungus causes more than 90 out of 100 cases of
ringworm of the scalp in North and Central America.1
In the past, the fungus Microsporum canis was the most
common cause, but it is a less frequent cause now. Microsporum canis is spread by cats and dogs.
Ringworm of the beard is
caused by Trichophyton verrucosum and is spread by
cattle, horses, or dogs.
You can catch ringworm by sharing
contaminated hats, combs, brushes, towels, telephones, clothing, sports
equipment, or even theater seats, and by direct contact with an infected
Children are more susceptible to the fungus and more
likely to get an infection than adults. Adults often do not get an
infection even after exposure to ringworm-causing fungi. Adults, and less
commonly children, can be carriers for ringworm. Carriers do not have symptoms of ringworm but can pass the infection on
Ringworm-causing fungi can live on people, objects (such as hats or
brushes), or animals for several months.