By Mayo Clinic Staff
Molluscum contagiosum (mo-LUS-kum kun-tay-jee-OH-sum) is a relatively common viral infection of the skin that results in 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 surrounding skin.
Though most common in children, molluscum contagiosum can affect adults as well — particularly those with weakened immune systems. In adults with an otherwise normal immune system, molluscum contagiosum involving the genitals is considered a sexually transmitted infection.
Molluscum contagiosum spreads through direct person-to-person contact and through contact with contaminated objects. The bumps associated with molluscum contagiosum usually disappear within a year without treatment but doctor-assisted removal is also an option.
Signs and symptoms of molluscum contagiosum include bumps on the skin that:
- Are raised, round and flesh colored
- Are small — typically under about 1/4 inch (smaller than 6 millimeters) in diameter
- Characteristically have a small indentation (umbilication) or dot at the top near the center
- Can become red and inflamed
- May be itchy
- Can be easily removed by scratching or rubbing, which can spread the virus to adjacent skin
- Usually appear on the face, neck, armpits, arms and tops of the hands in children
- May be seen on the genitals, lower abdomen and inner upper thighs in adults if the infection was sexually transmitted
When to see a doctor
If you suspect you or your child has molluscum contagiosum, consult your primary care doctor.
The virus that causes molluscum contagiosum spreads easily through:
- Direct skin-to-skin contact
- Contact with contaminated objects, such as toys, towels and faucet handles
- Sexual contact with an affected partner
Scratching or rubbing the bumps spreads the virus to nearby skin.
More widespread molluscum contagiosis infections may occur in people with weakened immune systems and in children who have atopic dermatitis.
The bumps and the skin around them may become red and inflamed. This is thought to be an immune response to the infection. If scratched, these bumps can become infected. If lesions appear on the eyelids, pinkeye (conjunctivitis) can develop.
You'll likely start by visiting your or your child's primary care practitioner. However, in some cases when you call to set up an appointment, you may be referred immediately to a doctor who specializes in treating skin conditions (dermatologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well-prepared for your appointment. Here's some information to help you get ready for your appointment, and know what to expect from your doctor.
What you can do
Before your appointment, write a list that answers the following questions:
- What symptoms are you experiencing?
- What, if anything, seems to improve your symptoms?
- What, if anything, appears to worsen your symptoms?
- What medications and supplements do you take on a regular basis?
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:
- When did you first begin experiencing symptoms?
- Have your symptoms been continuous or occasional?
- Have you had similar lesions in the past?
- Has anyone close to you had similar lesions?
Your doctor usually can diagnose molluscum contagiosum just by looking at it. If there's any doubt, he or she may take skin scrapings from the infected area and view them under a microscope.
Molluscum contagiosum usually gets better without treatment in six to 12 months. However, it's possible to continue developing bumps for up to five years. Once all of your bumps are gone, you're no longer contagious.
Doctors may recommend that the lesions be removed before they disappear on their own, particularly in adults, because they are so contagious. Treatments for molluscum contagiosum can be painful, so an anesthetic might be administered beforehand to lessen discomfort. Sometimes a combination of treatments may be used.
In some cases, prescription or over-the-counter medications applied directly to the lesions may be helpful. Examples include:
- Irritating products. These preparations often contain ingredients such as salicylic acid or potassium hydroxide that help dissolve the lesion over time. Others may cause a blister to form under the bump, lifting it off your skin.
- Topical creams. Prescription creams and gels containing retinoids — such as tretinoin (Atralin, Retin-A, others), adapalene (Differin) and tazarotene (Avage, Tazorac) — have been used to treat molluscum contagiosum. These medications cannot be used during pregnancy.
Surgical and other procedures
The methods doctors use to remove molluscum contagiosum bumps include:
- Freezing (cryotherapy)
- Laser therapy
Molluscum contagiosun doesn't stay in the body once the infection has cleared up, but you can be reinfected with this virus if you come in contact with someone who has an active infection.
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 personal items. This includes clothing, towels, hairbrushes or other personal items. Refrain from borrowing these items from others as well.
- Avoid sexual contact. If you have molluscum contagiosum on or near your genitals, don't have sex until the bumps are treated and have completely disappeared.
- Cover the bumps. Use a watertight bandage to cover your bumps if there's a possibility that another person may come in contact with infected skin. To keep your skin healthy, uncover it when you won't come in contact with other people.
Swimming pool precautions
It's not clear if the molluscum contagiosum virus can spread in the chlorinated water found in swimming pools. Experts suspect that it's more likely that swimmers transmit the virus through shared use of towels; equipment, such as kickboards; or direct skin contact. To help prevent the spread of molluscum contagiosum, cover the bumps with watertight bandages before swimming and don't share towels, water toys or kickboards.
March 21, 2015
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