Ringworm is a topical fungal infection of the skin, hair and nails. It is not, as the name infers, caused by a worm. In the medical community the infections are described as “tinea” infections so you may come across references to “tinea pedis”, “tinea corporis” and similar, describing the part of the body that is affected. Ringworm is highly contagious and can be spread in multiple ways via direct or indirect contact.
The incubation period is thought to be between 1 to 3 weeks depending on the part of the body that is affected. It is extremely common in adults with up to 20% of the population affected at any time. Animals are also susceptible including cats, dogs and domestic livestock. Here’s more information on how you get ringworm.
Ringworm of the body
The picture on the right shows a ringworm infection of the body (tinea corporis). It usually starts of a round reddish colored lesion with a dry, scaly edge. As the rash expands in a centrifugal pattern it develops a well defined “ring” surrounding a lighter area of skin.
The outer edge of the ring is typically well defined and may be raised and scaly in texture. If several lesions occur close to each other they can merge, forming a multi-lobed shape.
Ringworm infections are generally itchy and can also develop small pus filled bumps. Click for more skin fungus pictures.
Ringworm of the scalp
If the ringworm fungus affects the scalp in a condition also known as tinea captis, crusty round patches of skin will develop. The hair will fall out/break off in these areas leaving black dots on the scalp.
Ringworm on the scalp is generally more serious than other forms of ringworm and should be treated under close medical supervision. It is harder to treat topically as the fungus quickly becomes embedded within the hair follicle and harder to reach.
The condition is most common in children.
Ringworm of the nails
If the nails are infected (tinea unguium or onychomycosis) they become increasing yellow, brittle and crumbly in texture. As the infection progresses they can become distorted and detach from the nail base. As the fungus is less exposed than in skin infections, ringworm of the nails is harder to reach and nail fungus treatment can take take many months. Specialized topical nail lacquers such as Funginix or Zetaclear will be needed, offering special formulations designed to penetrate deeply into the nails.
It has been estimated that close to 40 million people in the US have an active nail fungus infection. It is more common in toenails than fingernails and the big toenail is the nail that is most often affected.
Cross infections between ringworm of the nails and ringworm of the foot (see below) are common.
Ringworm of the foot
Ringworm of the foot, also known as Athletes foot, toe fungus, foot fungus and tinea pedis, normally presents in the webbed area between the toes (especially if this is moist), but the sole of the foot and the sides can also be affected. Scaling, peeling and cracking of the skin is characteristic of the condition. The skin can also blister and rupture exposing raw tissue. See more foot fungus pictures.
There are also several other less common ringworm infection including tinea cruris or jock itch that affects the groin area, tinea mannum which affects the hands, tinea faciei where the face is affected, tine barbae which affects the facial hair.
Images for ringworm lesion, ringworm of the foot and scalp ringworm sourced from the CDC Public Image Health Library.
For most infections applying an antifungal cream or powder to the affected area is normally effective. The duration of most treatment courses is two weeks, but this may vary between products. In severe cases of ringworm and for scalp ringworm, medical advice is strongly recommended. See more on ringworm cures.