Although molluscum contagiosum is a common skin rash in kids, many parents have never heard of it. The most important thing to know about it is that, for most children, the rash is no big deal and goes away on its own over time.

About Molluscum Contagiosum

Molluscum contagiosum is a viral infection that causes a mild skin rash. The rash looks like one or more small growths or wart-like bumps (called mollusca) that are usually pink, white, or skin-colored. The bumps are usually soft and smooth and may have an indented center.

Infection is most common among kids between 1 and 12 years old, but also occurs in:

• teens and adults
• some athletes, such as wrestlers, swimmers, and gymnasts
• people whose immune systems have been weakened by HIV, cancer treatment, or long-term steroid use

As you might guess by its name, this skin disorder is contagious, and can be passed from one person to another. It is unknown how long the rash and virus may be contagious.

Causes

Molluscum contagiosum is caused by the molluscum contagiosum virus (MCV), a member of the poxvirus family. This virus thrives in warm, humid climates and in areas where people live very close together.

Infection with MCV occurs when the virus enters a small break in the skin's surface. Many people who come in contact with the virus have immunity against it, and do not develop any growths. For those not resistant to it, growths usually appear 2 to 8 weeks after infection.

Kids can get molluscum contagiosum in a few different ways. It spreads easily, and most commonly, through direct skin-to-skin contact, but kids can get it by touching objects that have the virus on them, such as toys, clothing, towels, and bedding. It can also spread in water.

Once someone has molluscum contagiosum, it can be spread from one part of the body to another by scratching or rubbing the bumps and then touching another part of the body.

Molluscum contagiosum also can be spread between sexual partners.

Signs and Symptoms

Because it is a skin infection, the only real sign or symptom of molluscum contagiosum are the small round pink, white, or skin-colored mollusca on the skin. These bumps are filled with a white, waxy pus core that contains the virus, and might have a shiny or "pearly" look.

Each molluscum starts out as a very small spot about the size of a pinhead and grows over several weeks into a larger bump that might become as large as a pea or pencil eraser. A tiny dimple (indentation) often develops on the top of each molluscum.

The mollusca can appear alone as a single bump or in groups, clusters, or rows. They can show up almost anywhere on the skin, but in kids are most commonly found on the chest, stomach, arms (including the armpits), legs, groin, genital area, and face.

In sexually active teens and adults, the bumps are usually located in the genital area or the inner thighs. Rarely, the bumps can occur around the eyes or around the mouth.

Most people develop between 1 and 20 mollusca. They're usually painless, but can become itchy, red, swollen, sore, and infected, especially if scratched.

Diagnosis

A doctor is likely to recognize molluscum contagiosum just by looking at the rash. The doctor might refer you to a dermatologist, a doctor who specializes in skin diseases.

In rare cases, the doctor or dermatologist will take a sample of the bump (either through a biopsy or by scraping an area of infected skin) to look at the cells under a microscope and confirm that the growths are mollusca.

Treatment

In many cases, molluscum contagiosum is left to go away on its own without treatment. Each individual molluscum typically disappears in about 2-3 months. However, new growths generally appear as old ones are going away, so it usually takes 6-18 months (and can take as long as 4 years) for molluscum contagiosum to go away completely.

Sometimes, doctors use treatments to remove the growths or help them go away more quickly, such as:

• removing the contagious center by squeezing the bumps with a scalpel or tweezers
• removing growths by freezing them (cryotherapy) or scraping them off with a sharp instrument (curettage)
• applying a chemical agent or cream, such as salicylic acid, tretinoin, cantharidin, benzoyl peroxide, or other wart medicine
• administering an oral drug called cimetidine

Although these treatments can sometimes help the disease resolve more quickly, most doctors do not use them on kids because they can be painful and burn, blister, discolor, or scar the skin. The use of treatment sometimes depends on the location and number of lesions. Some people request it if the rash is embarrassing or causes other problems, such as itching or other discomfort.

Treatment works best when started early because there are usually only a few growths. Your doctor will talk with you about the advantages and disadvantages of treatment and help you decide whether treatment is necessary. Be sure to talk with your doctor before trying any at-home remedies, including removing the bumps yourself.

Complications

Molluscum contagiosum generally causes no long-term problems, and the growths usually leave no marks. However, treatments might scar the skin, and some people develop a secondary infection, which can be treated with antibiotics.

People with weakened immune systems can sometimes get a more serious form of molluscum contagiosum. They typically have more mollusca, especially on the face. The growths are larger, look different, and usually are more difficult to treat. In these cases, doctors might prescribe medications that help strengthen the immune system.

Preventing the Spread of Molluscum Contagiosum

Because molluscum contagiosum is contagious and can spread to other parts of the body, someone who's infected should follow these precautions:

• Do not touch, scratch, or rub growths.
• Wash hands often with soap and water.
• Keep areas with growths clean.
• Try to cover each growth with clothing or a watertight bandage, especially before participating in activities in which equipment is shared or skin contact can occur, like swimming and wrestling.
• Change each bandage daily or when it becomes dirty.
• Do not shave over areas that have bumps.
• Moisturize the skin if dry.

As long as they follow these precautions until all of the bumps are gone, kids with molluscum contagiosum can still go to school or daycare, participate in sports, and play with other children.

A person can get molluscum contagiosum again through contact with someone who's infected, but this is rare.

To avoid infection, have your kids follow these tips:

• Wash hands often with soap and water.
• Do not share towels, clothing, and other personal items.
• Do not share kickboards and other water toys at swimming facilities.
• Do not touch or scratch bumps or blisters on your skin or other people's skin.

Reviewed by: Patrice Hyde, MD
Date reviewed: April 2013