Molluscum contagiosum (mo-LUS-kum kun-tay-jee-OH-sum) is a fairly common skin infection caused by a virus. It causes round, firm, painless bumps ranging in size from a pinhead to a pencil eraser. If the bumps are scratched or injured, the infection can spread to nearby skin. Molluscum contagiosum also spreads through person-to-person contact and contact with infected objects.
Though most common in children, molluscum contagiosum can affect adults as well — particularly those with weakened immune systems. Adults with a healthy immune system can develop molluscum contagiosum from sexual activity with an infected partner.
Left untreated, the bumps usually disappear in 6 months to 2 years.
Molluscum contagiosum signs and symptoms include:
- Raised, round, skin-colored bumps
- Small bumps — typically under about 1/4 inch (smaller than 6 millimeters) in diameter
- Bumps with a small dent or dot at the top near the center
- Itchy, pink bumps
- Bumps on the face, trunk, arms or legs of children
- Bumps on the genitals, lower abdomen or inner thighs of adults if the infection was sexually transmitted
When to see a doctor
If you suspect you or your child has molluscum contagiosum, contact your health care provider.
The virus that causes molluscum contagiosum spreads easily through:
- Skin-to-skin contact
- Contact with infected objects, such as towels, kickboards and wrestling mats
- Swimming in pools or hot tubs contaminated with the virus
- Sexual contact with an affected partner
- Scratching or rubbing the bumps, which spreads the virus to nearby skin
The bumps and the skin around them may become inflamed. This is thought to be an immune system response to the infection. If scratched, these bumps can become infected and heal with scarring. If sores appear on the eyelids, pink eye (conjunctivitis) can develop.
To help prevent the spread of the virus:
- Wash your hands. Keeping your hands clean can help prevent spreading the virus.
- Avoid touching the bumps. Shaving over the infected areas also can spread the virus.
- Don't share or borrow personal items. These include clothing, towels, hairbrushes and other personal items.
- Avoid sexual contact. If you have molluscum contagiosum on or near your genitals, don't have sex until the bumps are treated and gone.
- Cover the bumps. Cover the bumps with clothing when around others, to prevent direct contact. Leave the affected area open to the air when not around others, as this promotes healthy skin. When swimming, cover the bumps with a watertight bandage.
Health care providers usually can diagnose molluscum contagiosum just by looking at it. If there's any doubt, they may take skin scrapings from the infected area and view them under a microscope.
Molluscum contagiosum usually gets better without treatment in 6 months to 2 years. Once the bumps are gone, you're no longer contagious. After healing, it's possible to become reinfected with the virus.
For severe or widespread disease, your health care provider might refer you to a specialist in skin conditions (dermatologist) to discuss options for removing the bumps.
Treatment might involve one or a combination of the following:
- A medicine that irritates the sores, such as retinoic acid or benzoyl peroxide
- A medicine that causes blisters (cantharidin), which lifts off the bumps
- Freezing (cryotherapy)
- Laser therapy, which might be an option for people with a weakened immune system
Some procedures can be painful, so your health care provider may numb your skin first. Possible side effects of treatment are infection and scarring.
Preparing for your appointment
You'll likely start by visiting your or your child's health care provider. Or you may be referred to a doctor who specializes in treating skin conditions (dermatologist).
Here's some information to help you get ready for your appointment, and know what to expect from your health care provider.
What you can do
Before your appointment, write a list that answers the following questions:
- What symptoms are you or your child experiencing?
- What, if anything, seems to improve the symptoms?
- What, if anything, appears to worsen the symptoms?
- What medications and supplements do you or your child take on a regular basis?
What to expect from your doctor
Your health care provider may ask:
- When did the symptoms begin?
- Do the symptoms come and go or are they nonstop?
- Have you or your child had similar bumps in the past?
- Has anyone close to you or your child had similar bumps?