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Ringworm: Treatment, Pictures, Causes, and Symptoms

What Is Ringworm?

A magnification of the skin disorder ringworm (tinea)

Ringworm is a common skin disorder otherwise known as “tinea” or “dermatophytosis.” It is caused by a fungus that can live on skin, surfaces like locker room floors, and household items like towels, bedding, and clothes. While there are multiple forms of ringworm, the most common forms affect:

  • the skin on the body (tinea corporis),
  • the scalp (tinea capitis),
  • the feet (tinea pedis, or "athlete's foot"), or
  • the groin (tinea cruris, or "jock itch").

Ringworm attacks dead tissues in places like the hair, nails, and leftover dandruff. But our bodies’ immune reactions and local bacterial infections enable ringworm to turn healthy, living skin red and itchy.

Does Ringworm Mean I Have Worms?

Ringworm is not caused by worms, as the name implies.

Despite its name, ringworm is not caused by a worm. The ancient Greeks called ringworm “herpes,” meaning “ring,” while the ancient Romans called it “tinea,” referring to the larval stage of a clothes moth. Characterized by round skin lesions (rings) and early belief that the infection was caused by a parasite (worm), the English word “ringworm” was born sometime in the early 15th century. While the condition is actually the result of a fungal infection by an organism called a dermatophyte, the name ringworm has stuck.

Ringworm Is a Fungus

It wasn’t until 1841 that anyone realized fungus could be responsible for ringworm. In that year, Hungarian physician David Gruby demonstrated that favus, a ringworm of the scalp, was caused by fungal infection. Unfortunately his research was largely ignored. In 1934 Chester Emmons published a careful study of several species of dermatophytes, which helped pave the way for our modern understanding of the disease.

Ringworm During WWII

When American servicemen started contracting ringworm in the humid Pacific Theater during WWII, the U.S. government launched an intensive study of fungal diseases. Before that study, scattered studies of dermatophytes conducted in isolation had led researchers to give about 1,000 different names to about 350 species of related fungus. That study made great progress in clearing up much of the confusion.

How Do You Get Ringworm?

Ringworm fungi are known as dermatophytes.

Although the world is full of yeasts, molds, and fungi, only a few cause skin problems. Ringworm fungi are known as dermatophytes -- microscopic organisms that feed on the dead tissues of your skin, hair, and nails, much like a mushroom can grow on the bark of a tree. Dermatophytes cause superficial infections—so-called because they occur on the surface of the skin.

What Causes Ringworm?

Ringworm is more common in unsanitary and crowded places. That’s because it can live on both skin and surfaces like shower floors, and can be transferred by sharing clothes, sheets, and towels. Even other mammals, including cats and dogs, can easily transfer ringworm to humans.

What Are the Types of Ringworm?

Multiple forms of ringworm affect different parts of the body.

There are several types of ringworm (tinea), and they tend to specialize. Different ringworm fungi target different body parts, including:

  • the face,
  • the scalp,
  • the hands,
  • the beard,
  • the groin,
  • the foot, and
  • the nails.

Keep in mind that the various types of ringworm don’t refer to specific fungal species—more than one species of fungus can cause many of the different forms of ringworm. Instead, the names of different ringworm types refer to where they occur on the body.

Ringworm of the Body (Tinea Corporis)

Ringworm of the body (tinea corporis)

Tinea corporis refers to ringworm of the trunk, legs, or arms. Different fungi cause tinea corporis in different parts of the world. It’s common for this infection to originate in the feet or nails, then spread to other body parts. It may spread to the:

  • feet,
  • scalp,
  • groin, or
  • nails.

When fungus affects the skin of the body, it often produces the round spots of classic ringworm, which is characterized by a red ring of scaly skin that grows outward as the infection spreads. Though children are especially susceptible to catching ringworm, it can affect adults as well.

Acute and Chronic Ringworm of the Body

Tinea corporis can be acute or chronic. When acute, the fungus causes suddenly appearing, itchy, red patches that may fill with pus and spread rapidly. When chronic, tinea corporis spreads by slightly inflamed rashes more slowly, and tends to appear in body folds. Widespread chronic tinea corporis is harder to treat and is more likely to reappear.

How Fast Can Ringworm Be Treated?

With treatment, tinea corporis usually goes away within four weeks. Avoid scratching, as this may lead to skin infection.

Ringworm of the Body (Tinea Corporis): Circular Rash

It is important to distinguish ringworm of the body (tinea corporis) from similar common rashes.

One of the most distinctive signs of tinea corporis (ringworm) is the appearance of an itchy, red, circular rash in the shape of a ring. This rash may resemble a target or a bullseye, and it usually has raised edges. Finding one of these is a helpful way to distinguish this rash from other even more common rashes such as eczema. Eczema and other rashes may appear similar to ringworm, but they require very different treatment.

Ringworm vs. Lyme Disease

One note of caution, though—another skin disease can also cause bullseye rashes. Lyme disease is a serious condition that can cause nerve pain, facial drooping, and brain inflammation, and its characteristic rash is also in the shape of a bullseye. One way to tell the difference is the raised lines that usually accompany ringworm rashes. While ringworm is caused by a fungus, Lyme disease is bacterial, so again, treatment for the two skin conditions is very different. Because of the serious consequences of Lyme disease, anyone in doubt should seek medical attention immediately.

Ringworm of the Hand (Tinea Manuum)

Ringworm of the hand (tinea manus)

Tinea manuum finds its way onto human hands through either soil, animals, or human contact. This form of ringworm is fairly uncommon and frequently confused with other skin conditions. Symptoms of tinea manuum may include:

  • an inflamed rash, often with raised borders,
  • peeling on the palm,
  • dryness on the palm,
  • mild itching on the palm, and
  • a blistered rash with sticky, clear fluid on the edges of the palm or fingers.

Often these symptoms are also present on both feet. The people most likely to:

  • contract tinea manuum are those who
  • sweat intensely,
  • frequently engage in manual labor, or
  • already have hand dermatitis.

Ringworm of the Nails (Tinea Unguium)

Ringworm of the nails (tinea unguium)

Tinea unguium is usually caused by one of two fungi: Trichophyton rubrum or T. interdigitale. Although tinea unguium can refer to fungal infection of the fingernails or toenails, toenails are much more likely to contract this disease. Those especially prone to ringworm of the nails include men, older adults, diabetics, people with peripheral vascular disease, or anyone with a compromised immune system.

Some of the symptoms of tinea unguium include:

  • yellow, brown, or otherwise discolored nails,
  • hard nails,
  • brittle nails,
  • thick nails, and
  • nails that have an irregular shape.

Without proper treatment, a nail infected with this fungal infection is at risk of falling off.

Ringworm of the Face (Tinea Faciei)

Ringworm of the face (tinea faciei)

Tinea faciei refers to ringworm infections on the face. This is an uncommon infection, and it can arise from contact with several sources, including:

  • cats,
  • dogs,
  • cattle,
  • ringworm of the nail (tinea unguium), and
  • ringworm of the feet (tinea pedis).

Some of the common features of tinea faciei include patches that are:

  • red, scaly, and round or oval,
  • often healed or less scaly and red in the middle, and
  • easily aggravated by sunlight.
  • Perhaps because it is uncommon, tinea faciei is often misdiagnosed as psoriasis, rosacea, contact allergic dermatitis, or many other non-fungal skin conditions.

Ringworm of the Scalp (Tinea Capitis)

Ringworm of the scalp (tinea capitis)

Tinea capitis is most common in children between the ages of 3 and 7, and is less often found in adults. The hair itself can be infected by various ringworm fungi, which may be spread from cattle, horses, pigs, dogs, and cats (especially kittens). One common culprit in the United States is T. tonsurans, which is spread from person to person, often has no symptoms, and is common in adults.

Some of the symptoms of ringworm on scalp include:

  • dry scaling similar to dandruff that is accompanied with hair loss,
  • yellow crusts and matted hair,
  • black dots of hair broken off at the scalp, with a scaly surface,
  • swollen lymph glands on the neck
  • a smooth spot where the hair has fallen off, and
  • an intensely inflamed mass similar to an abscess.

Ringworm of the Foot (Tinea Pedis, Athlete’s Foot)

Ringworm of the foot (tinea pedis)

If you have tinea pedis, the good news is you’re not alone. This is the most common form of ringworm in humans. The bad news? It’s also the most difficult to treat.

The bane of locker rooms and dormitory showers, tinea pedis can be an itchy, painful problem. Tinea pedis is most often found on the feet of young adult men. Ringworm on the foot can appear with several different types of symptoms, including:

  • dry scaling on the soles of feet that is patchy and fine,
  • clusters of blisters on the sides of the feet,
  • round, dry patches on the top of the feet,
  • dry soles that are not inflamed, and
  • moist, peeling skin between toes (athlete’s foot).

How Does Ringworm Spread?

Anytime you walk around barefoot in a communal shower, bathroom, changing room, or swimming pool, you risk being infected with tinea pedis. Even if the facility hasn’t been used for months, the spores of the fungus may still be active on the surface.

What Does Athlete’s Foot Look Like?

Athlete’s foot is one common form of tinea pedis. If you find the skin between your toes moist, soft and easily pulled away, athlete’s foot is a likely cause. Athlete’s foot can cause a painful split in the skin, and it may give off an unpleasant smell. The symptoms of aAthlete’s foot may not be caused by ringworm at all. They It can also be caused by:

  • bacterial infections,
  • mold infections,
  • skin conditions like psoriasis and eczema,
  • injury, and
  • a buildup of thick corns due to toes pressing into each other.

Athletes are more likely to get athlete’s foot because they fall into many categories at risk for this infection, including:

  • wearing shoes with poor ventilation,
  • sweating intensely,
  • keeping feet wet for long periods, and
  • walking through common areas like locker rooms and showers.

What Is Jock Itch? (Ringworm of the Groin, Tinea Cruris)

Ringworm of the groin (tinea cruris)

Another itchy problem is tinea cruris, more commonly known as jock itch. Most common among adult men, tinea cruris causes a scaly, reddish-brown rash with raised borders to form down the inner thighs. Sometimes ring-like rashes form on the buttocks as well. This infection is unlikely to form on the penis or vulva, or around the anus.

Although jock itch is common, it is sometimes confused with other common conditions, such as:

  • yeast infection,
  • psoriasis, and
  • intetrigo, a chafing rash which results from skin rubbing against skin.

Ringworm of the Beard (Tinea Barbae, Barber’s Itch)

Ringworm of the beard (tinea barbae)

Like certain forms of ringworm of the scalp, tinea barbae infects the hair itself on a man’s face. Beards and moustaches make fertile feeding grounds for the fungi responsible for tinea barbae. In the days when men frequently stopped by the barber shop for a shave, this disease was once commonly spread by barbers with unsanitary practices. Today, tinea barbae is most common among farmers. Two of the fungi most commonly responsible for the condition, T. verrucosum and T. mentagrophytes, are carried by cattle and horses, respectively.

Common symptoms of tinea barbae include:

  • swelling and marked crusting,
  • red, lumpy areas around the face,
  • itching,
  • hairs that are easily pulled out, and
  • facial hair that breaks off.

Tinea barbae can appear on the face or neck.

Is Ringworm Contagious?

Ringworm is highly contagious and can be spread multiple ways.

Ringworm is highly contagious. The many fungi that cause ringworm thrive in warm, moist areas, making locker rooms, public restrooms, showers, public pools, saunas, and similar areas especially likely places to contract the disease. There are three ways ringworm can be contracted, based on the three groups of fungi that cause infections:

  1. Zoophilic: “Animal-loving” fungi that live on cats, dogs, horses, cows, poultry, and other mammals.
  2. Anthropophilic: “man-loving” fungi that are transmitted from person to person.
  3. Geophilic: “earth-loving” fungi that occur naturally in the soil.

The most common source of ringworm for humans comes from the fungus Microsporum canis, which is usually found on cats and dogs (particularly cats). Sometimes the pets who carry ringworm show no symptoms themselves.

Ringworm Causes

To become infected, a person must come in contact with either an infected skin or hair fragment or a fungal spore. Spores can live for years in blankets, clothing, bedding, combs and other places. To make matters worse, botanists believe these spores are airborne, meaning you don’t actually have to touch a person, animal, or surface that is already infected—merely being near ringworm spores may be enough to become infected.

Ringworm in Dogs and Cats

Pets can develop ringworm and spread it to people.

When a person contracts ringworm, dogs and cats are the most common culprits. Cats are particularly susceptible to ringworm. One study showed that when a cat has ringworm, there is a 30 to 70 percent chance someone in the household will contract the disease, too.

How Long Does Ringworm Last in Cats?

Ringworm on a cat usually goes away without treatment, but it takes nine months to a year. During that time the cat’s hair will continue to fall out, putting it at greater risk of wounds and infections. Plus the cat remains contagious to anyone in the home. Symptoms of ringworm in cats include:

  • Broken or stubbly hair
  • Crusty, scaling skin
  • Changes in hair or skin color
  • Inflamed skin
  • Circular spots where hair has fallen out
  • Excessive grooming
  • Infected claws
  • Dandruff

With treatment, a cat can be cleared of ringworm in as little as six weeks, though curing a cat’s ringworm can take much longer.

Ringworm in Dogs

For dogs, ringworm infection usually comes from the fungal species Microsporum canis, Microsporum gypseum and Trichophyton mentagrophytes. Unlike cats, dogs often (but not always) show symptoms of ringworm. The main symptom dogs with ringworm show are hairless, circular lesions on the head, ears, paws, and forelimbs. These lesions expand, and when they do, they become more irregular in shape and may become scabby. Puppies, malnourished or stressed dogs, and dogs that have been in a kennel or shelter are especially prone to ringworm.

Ringworm Treatment for Dogs

A veterinarian will determine the severity of a ringworm infection before recommending treatment for an infected dog. There are various treatments for treating dogs with ringworm, including shampoos, ointments, dips, oral treatments and simply clipping back fur.

The lesions caused by ringworm should begin to clear up in about one to three weeks. But keep treating your dog for as long as the veterinarian recommends. Just because a lesion heals does not necessarily mean the infection has been cured.

Ringworm and Other Animals

Cats and dogs aren’t the only mammals susceptible to ringworm. Ringworm can be transmitted from horses, pigs, cattle, rodents, and hedgehogs. These are only some of the animals that might pick up this potentially itchy, burning disease.

How Ringworm is Diagnosed

A physician can diagnose or rule out ringworm by taking a skin sample for culture.

Some forms of ringworm are easier to spot than others. The telltale signs of red, raised rings can alert medical professionals to the infection, which makes diagnosis simple.

At other times, however, ringworm can be difficult to diagnose. Certain types of ringworm are particularly resistant to diagnosis, such as ringworm of the face and hands. In these cases, the fungus can cause infections that resemble many other common skin diseases. If a dermatologist has trouble diagnosing ringworm, a small scraping of the skin is usually taken. That scraping can then be cultured in a laboratory or studied under a microscope to confirm what has caused the infection in the first place.

Ringworm Treatment

Ringworm is usually treated with topical antifungal creams.

Fungal diseases like ringworm are more difficult to treat than bacterial infection. That’s because fungus have more complicated cells which are more similar to our own. This makes it difficult to develop antifungal drugs that will kill the fungus, but do no harm to humans.

As a result, long-term topical and oral treatments are necessary, and they may not be 100 percent effective. Even after the infection appears to have disappeared, once ringworm appears once it is more likely to reoccur.

How to Get Rid of Ringworm

Ringworm can be treated topically with antifungal creams containing:

  • clotrimazole (Cruex, Desenex, Lotrimin),
  • miconazole (Monistat-Derm),
  • ketoconazole (Nizoral), and
  • terbinafine (Lamisil).

In severe or resistant infections on the scalp or nails, oral medications are necessary, such as:

  • terbinafine,
  • itraconazole (Sporanox), and
  • fluconazole (Diflucan).

Can You Prevent Ringworm?

Simple guidelines can help reduce the risk of ringworm.

Ringworm is a very common infection, and anyone can contract it. There are some people who are especially prone to infection, though. Anyone with a compromised immune system is both at a higher risk of being infected by ringworm and will have a harder time fighting off an infection. People who use public locker rooms, showers, swimming pools, and similar communal areas that are hot and humid are also at greater risk.

Athletes risk infection because they tend to sweat, and their athletic equipment sometimes traps moisture close to the skin. Athletes who make a lot of skin-to-skin contact, such as wrestlers and MMA fighters, are particularly prone to skin infections like ringworm. People who spend a lot of time with animals—farmers, veterinarians, and dog groomers, for example—are also at greater risk of making contact with the fungi that cause ringworm.

It’s not easy to prevent ringworm completely. However, by taking a few simple steps, your risk of developing ringworm will be less. The next several slides provide some helpful prevention tips in minimizing the chance of developing ringworm.

Ringworm Prevention: Don’t Share

Ringworm prevention tip #1: Don't share clothing, sports gear, towels, or sheets.

To keep ringworm off your feet, don’t walk around barefoot in locker rooms, public pools, or public showers. Instead, put on a pair of sandals or slippers to give your skin a barrier of protection from the ringworm fungi.

Ringworm Prevention: Slip on Sandals and Slippers

Ringworm prevention tip #2: Wear slippers or sandals in locker rooms and public pool and bathing areas.

To keep ringworm off your feet, don’t walk around barefoot in locker rooms, public pools, or public showers. Instead, put on a pair of sandals or slippers to give your skin a barrier of protection from the ringworm fungi.

Ringworm Prevention: Get Soapy

Ringworm prevention tip #3: Shower and shampoo well after any sport that includes skin-to-skin contact.

If you play a contact sport, shower and shampoo carefully after every practice or game. The same rule applies after petting a dog or cat; tTo avoid transmission of the ringworm virus from your pets, be sure to wash your hands with soap and water after playing with any mammal.

Ringworm Prevention: Change Is Good

Ringworm prevention tip #4: Wear loose-fitting cotton clothing. Change your socks and underwear at least once a day.

To avoid trapping moisture close to your skin, wear loose-fitting clothing made of natural fibers. Change your socks and underwear at least once a day to ward off athlete’s foot and jock itch.

Ringworm Prevention: Stay Dry

Ringworm prevention tip #5: Keep your skin clean and dry. Always dry yourself completely after showers or baths.

Ringworm fungi love humidity. One of the best ways to keep them away is to stay dry. For instance, completely dry yourself off after showers and baths.

Ringworm Prevention: Socks on First

Ringworm prevention tip #6: If you have athlete's foot, put your socks on before your underwear so that fungi do not spread from your feet to your groin.

Stay stocking-footed to prevent the spread of any foot fungus to other parts of your body. Before you slide on your underwear, make sure your socks are on tight. This may prevent a case of athlete’s foot from turning into an uncomfortable case of jock itch.

Ringworm Prevention: Watch for Patchy Pets

Ringworm prevention tip #7: Take your pet to the vet if it has patches of missing hair, which could be a sign of a fungal infection.

If your pets have patches of missing hair, take them to the vet. That’s one sign of a ringworm fungal infection. Also keep an eye out for a lesion with a scaly center that looks red and irritated around the edges. Sometimes pets will show circular patches of missing hair, and at other times they will display crusty scales. If you have a cat, keep an eye out for excessive grooming, which may be your cat’s way of signaling something is irritating its skin.

Ringworm: Treatment, Pictures, Causes, and Symptoms

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