What is molluscum contagiosum?
Molluscum contagiosum is a skin condition that causes raised, round, smooth-surfaced bumps on the skin. They look like thick-walled pimples. The bumps, called mollusca, are usually found on just one area of the body.
- have a waxy or skin-colored surface
- may have a dimple (indent) in center
- are firm (there is a white material rather than pus in cores of the bumps)
- are many different sizes, from pinhead to 1/4 inch across
- are occasionally itchy, but not painful.
This diagnosis usually requires that the child be examined by a healthcare provider.
What is the cause?
Molluscum contagiosum is caused by a poxvirus. It is transmitted by skin-to-skin contact (close contact) with an infected person. Children 2 to 12 years old are most likely to be infected by this virus. Mollusca can spread to other parts of the body if a child picks at a bump and then scratches elsewhere.
How long does it last?
Most mollusca disappear without treatment in 6 to 18 months. Mollusca can spread rapidly and last longer in children who also have eczema (sensitive, dry skin). If repeatedly picked at, mollusca can become infected with bacteria and change into crusty sores (impetigo). Most children develop only 5 to 10 mollusca, but some acquire more. Regardless of the number, they are a temporary condition.
How is it treated?
- To treat or not to treat?
Because mollusca are harmless, painless, and have a natural tendency to heal and disappear, some providers recommend not treating them. The treatment itself may be painful and frightening, especially to younger children. In addition, treatment may be unsuccessful or need to be repeated.
Treatment of mollusca will be considered if your child picks at them, the mollusca are in areas of friction (for example, the armpit), you feel they are a cosmetic problem, or they appear to be spreading rapidly.
- Removal techniques
The following techniques must be performed in a doctor's office. The mollusca can be destroyed with freezing (cryotherapy) or burning with a mild acid. Another type of treatment involves piercing the center of the mollusca with a needle or scalpel and scraping out the core. Newer techniques may become available.
- Duct tape technique: Covering 3 of the molluscum with duct tape sometimes irritates them and makes all of them go away in a few weeks. It’s worth a try.
- Preventing the spread of mollusca to other areas of your child's body
Every time your child picks at a molluscum and then scratches another area of skin with the same finger, a new site of mollusca can form. To prevent this spread, discourage your child from picking at the molluscum. Chewing or sucking on a molluscum can lead to similar bumps on the lips or face. If your child is doing this, cover the molluscum with a Band-Aid. Keep your child's fingernails cut short and wash your child's hands more frequently.
Mollusca are only mildly contagious to other people. (The incubation period is 4 to 8 weeks.) However, they are easily spread in warm water. Avoid having your child in a bath or hot tub with other children. Your child can attend child care, preschool, and school without undue concern about spread.
When should I call my child's healthcare provider?
Call during office hours if:
- A molluscum becomes open and looks infected.
- Your child continues to pick at the molluscum.
- The mollusca are spreading rapidly.
- You have other questions or concerns.
Written by B.D. Schmitt, MD, author of "Your Child's Health," Bantam Books.
Published by RelayHealth.
Last modified: 2009-06-19
Last reviewed: 2010-06-02
This content is reviewed periodically and is subject to change as new health information becomes
available. The information is intended to inform and educate and is not a replacement for medical
evaluation, advice, diagnosis or treatment by a health care professional.