What Is Molluscum Contagiosum?
Molluscum contagiosum is a skin infection that is caused by a virus. The virus, called the molluscum virus, produces benign raised lesions, or bumps, on the upper layers of your skin.
The small bumps usually are painless. They disappear on their own and rarely leave scars when left untreated. The length of time the virus lasts varies for each person, but the bumps can last from two months up to four years.
Molluscum contagiosum is spread by direct contact with the lesion of an infected person or by contact with a contaminated object such as towels or piece of clothing.
Medication and surgical treatments are available, but in most cases, treatment is not necessary. The virus can be more difficult to treat if you have a weakened immune system.
Causes of Molluscum Contagiosum
You can contract molluscum contagiosum by touching the lesions on the skin of an infected person. Children can contract the virus during normal play with other children.
Teens and adults are more likely to become infected through sexual contact. You can also become infected during contact sports—such as wrestling or football—that involve bare skin interactions.
The molluscum virus can survive on surfaces that have been touched by the skin of an infected person. Therefore, it’s possible to contract the virus by handling towels, clothing, toys, or other items that have been contaminated.
Molluscum contagiosum also can be transferred by shared sports equipment where an athlete’s bare skin comes in contact with the object. The virus can be left and passed to the next person on items such as baseball gloves, wrestling mats, and football helmets.
If you have this condition, you can spread the infection throughout your body. You can transfer the virus from one part of your body to another by touching, scratching, or shaving a bump and then touching another part of your body.
Risk Factors for Molluscum Contagiosum
While no one is entirely risk-free molluscum contagiosum, certain groups are more likely to become infected than others. They are:
- children between the ages of 1 and 10
- residents of tropical climates
- individuals with weakened immune systems caused by factors such as HIV, organ transplants, or cancer treatments
- patients who have atopic dermatitis, a common form of eczema that causes scaly and itchy rashes
- athletes who participate in contact sports such as wrestling or football, in which bare skin-to-skin contact is common
Symptoms of Molluscum Contagiosum
If you or your child comes in contact with the molluscum virus, you may not see symptoms of infection for up to six months. The average incubation period is between two and seven weeks.
You may notice the appearance of a small group of painless lesions. These bumps may appear alone or in a patch of as many as 20. They usually are:
- very small, shiny, and smooth in appearance
- flesh-colored, white, or pink
- firm and dome-shaped with a dent or dimple in the middle
- filled with a central core of waxy material
- between 2 millimeters (the size of the head of a pin) and 5 millimeters (the size of an eraser on the top of a pencil) in diameter
- found anywhere except on the palms of your hands or the soles of your feet
- usually present on the face, abdomen, torso, arms, and legs
- located on the inner thigh, genitals, or abdomen in adults
However, if you have a weakened immune system, you may have symptoms that are more significant. Lesions may be as large as 15 millimeters in diameter, which is about the size of a dime. The bumps appear more often on your face and are typically resistant to treatment.
Complications of Molluscum Contagiosum
Most complications of molluscum contagiosum are secondary skin infections. These infections are caused by bacteria and may cause pain, soreness, or inflammation.
Removing the bumps by scratching, or having them removed by a physician using cryotherapy (freezing) or curettage (scraping) techniques can result in pain, irritation, or permanent scarring.
Diagnosis of Molluscum Contagiosum
Because the skin bumps caused by molluscum contagiosum have a distinct appearance, your physician often can diagnose the infection by merely looking at the affected area. A skin scraping or biopsy can confirm the diagnosis.
While it is usually unnecessary to treat molluscum contagiosum, always have your physician examine any skin lesions that last longer than a few days. Confirm the diagnosis of molluscum contagiosum to rule out other causes for the lesions, such as skin cancer, chickenpox, or warts.
Treatment of Molluscum Contagiosum
In most cases, if you have a normal immune system, it will not be necessary to treat the lesions caused by molluscum contagiosum. The bumps will fade away without intervention.
However, some circumstances may justify the need for treatment. If your lesions are large and located on your face and neck, if you have an existing skin disease such as atopic dermatitis, or if you have serious concerns about spreading the virus, you might be a candidate for treatment.
The most effective treatments for molluscum contagiosum are performed by a healthcare provider and include:
- cryotherapy—liquid nitrogen is used to freeze each bump
- curettage—a small tool is used to pierce the bump and scrape it off the skin
- laser therapy—a laser is used to destroy each bump
- topical therapy—creams containing acids or chemicals are applied to the bumps to induce peeling of the top layers of the skin
In some cases, these techniques can be painful and cause scarring. Anesthesia may also be necessary.
Since these methods involve treating each bump, a procedure may require more than one session. If you have many large bumps, re-treatment may be necessary every three to six weeks until the bumps disappear. New bumps may appear as the existing ones are treated.
In some cases, your physician may prescribe the following medications:
- trichloroacetic acid,
- topical podophyllotoxin cream (such as Condylox), which is derived from plant resins
- cantharidin (Cantharone, obtained from the blister beetle), applied by the doctor,
- imiquimod (Aldara), a topical cream that works by boosting the immune system (Although this drug is currently approved only for treatment of genital warts, it has been found to be effective against MC and can be applied at home.)
- cimetidine (Tagamet), the antiulcer and antiheartburn medication (This drug has been reported to be useful in the treatment of MC. However, the FDA for the treatment of MC has not officially approved it.)
- cidofovir (Vistide), used through IV for eye infections in people with AIDS (This drug has been shown to be effective when applied topically to severe MC lesions. However, it has not officially been approved by the FDA for the treatment of MC.)
If you are pregnant or are planning to become pregnant, or if you are breastfeeding, let your physician know about your condition before taking these or any other medications.
If you have an immune system that is weakened by diseases such as HIV or by drugs such as those used for treating cancer, it may be necessary to treat molluscum contagiosum. Successful treatment is more difficult for people with weakened immune systems than it is for those with normal immune systems.
Antiretroviral (anti-HIV) medications are the most effective treatment for HIV patients infected with molluscum contagiosum because these medications can work to strengthen the immune system to fight the virus.
The Centers for Disease Control and Prevention (CDC) warns against self-treatment of molluscum contagiosum without the advice of a healthcare provider. According to the CDC, treatments available from online sources may not work. They can even harm, rather than help, your condition (CDC).
Long-Term Outlook for Molluscum Contagiosum
A molluscum contagiosum infection will usually go away on its own if your immune system is healthy. Typically, this happens gradually—within six to 12 months—and without scarring. However, for some, it may take from a few months up to a few years for your bumps to disappear. The infection can be more persistent and last even longer for people with immune system problems.
Once the lesions fade, the molluscum virus is no longer present in your body. When this happens, you can’t spread the virus to others or to other parts of your body. You will see more bumps only if you become infected again. Unlike with chickenpox, if you have had molluscum contagiosum once, you are not protected against being reinfected.
How to Prevent the Spread of Molluscum Contagiosum
The best way to avoid getting molluscum contagiosum is to avoid touching the skin of another person who has the infection. In addition, these suggestions can help you prevent the spread of the infection:
- Practice effective hand washing with warm water and soap.
- Instruct children in proper hand-washing techniques since they are more likely to use touch in play and interaction with others.
- Avoid sharing personal items such as towels, clothing, hair brushes, or bar soaps.
- Avoid using shared sports gear that may have come in direct contact with an athlete’s bare skin.
- Avoid picking at or touching areas of your own skin where the bumps exist.
- Keep the bumps clean and covered to prevent yourself or others from touching them and spreading the virus.
- Avoid shaving or using electrolysis where the bumps are located.
- Avoid sexual contact if you have bumps in the genital area.