Molluscum contagiosum is a common condition where small warty bumps (mollusca) appear on the skin. It is caused by a virus that can be passed on by skin contact or from contaminated towels, flannels, etc. It is not serious and usually clears within 12-18 months without any treatment. Treatment may be considered if the mollusca are unsightly. If the first mollusca to appear are on the lower abdomen or around the penis or vagina then it may have been caught from sexual contact. If this occurs then you should consider being checked out for sexually transmitted diseases.
What does molluscum contagiosum look like?
The skin develops small lumps which are pearly-white or slightly pink. Each lump (molluscum) looks like a small wart and is round, firm, and about 1-5 mm across. A tiny dimple often develops on the top of each molluscum. If you squeeze a molluscum, a white cheesy fluid comes out. In most cases fewer than 20 mollusca develop. Sometimes many mollusca develop over various parts of the skin. They tend to occur in groups or clusters. Any part of the body can be affected but it is rare on the palms and soles.
For a list of websites that contain pictures of skin conditions, including molluscum contagiosum, see www.patient.co.uk/showdoc/1097/
What causes molluscum contagiosum?
It is caused by a virus which can be passed on by skin-to-skin contact. You can also be infected by touching things that have been contaminated by the virus. For example, by sharing towels or flannels that have been used by someone who has molluscum contagiosum.
Once one area of skin is affected, the mollusca can spread to other areas of your skin. However, most people are resistant (immune) to this virus. Therefore, most people who come into contact with affected people do not develop molluscum contagiosum.
Molluscum contagiosum most commonly affects young children, but it can affect anyone of any age.
Molluscum contagiosum is not classed as a sexually transmitted disease as such. However, sometimes the virus is passed on during the close skin-to-skin contact of having sex. About 2 in 10 men and 1 in 10 women who have mollusca also have a sexually transmitted disease. If it is passed on whilst having sex then the first mollusca to appear tend to be on the skin of the lower abdomen and around the penis, vagina or anus. If this occurs then you should consider being checked out for sexually transmitted diseases.
How does molluscum contagiosum develop?
The mollusca (the warty skin bumps) develop 2-8 weeks after you become infected with the virus. Typically, each molluscum lasts about 6-12 weeks, crusts over, and then goes. However, new ones tend to appear as old ones are going as the virus spreads to other areas of skin. Therefore, crops of mollusca may appear to come and go for several months. It commonly takes 12-18 months before the last of the mollusca goes completely. Occasionally, the condition lasts longer than two years - sometimes as long as five years.
For some people, the main concern is that the mollusca can look unsightly. However, most people are not too bothered by it.
Is molluscum contagiosum serious?
Mollusca are not usually itchy, painful, or serious. A scar is not usually left when they go, but sometimes a tiny pitting (indented) scar remains. In a few people the skin looks a little lighter where each molluscum had been. Occasionally, the skin next to a molluscum becomes infected with bacteria. This can be treated with antibiotics. Rarely, a molluscum on an eyelid causes eye inflammation. (See a doctor if you develop any eye symptoms related to a molluscum.) After an episode of molluscum contagiosum has cleared away, you will normally be immune to the virus and further episodes only occur rarely.
If you develop a very large number of mollusca (hundreds) or the mollusca are larger than normal, it could be a marker of an underlying immune deficiency. For example, as a consequence of chemotherapy or HIV infection. This may need specialist assessment.
Can infection with molluscum contagiosum be prevented?
The chance of passing on the molluscum contagiosum virus to others is small, and it is not serious anyway. Therefore, there is no need to keep away from other people.
To reduce the chance of passing it on to others, it is sensible not to share towels, clothes or bath water. Also, try to avoid skin-to-skin contact with other people. For example, by covering affected areas with clothing. Also, try not to scratch the mollusca as this may increase the risk of spreading the rash to other areas of your skin. Molluscum contagiosum is contagious until the last molluscum has gone.
If you have, or your partner has, mollusca, a condom should be used during sex. This will not completely stop skin-to-skin spread but will reduce the chance of passing it on considerably.
What is the treatment for molluscum contagiosum?
It is usually best not to treat because:
- The mollusca will usually go away without treatment within 12-18 months. Having mollusca does not limit your activities such as going to work, sports, swimming, etc.
- Many of the treatments can be painful (such as liquid nitrogen).
- Some treatments have a risk of burning the surrounding skin.
- All treatments have a small risk of scarring the skin. But, scarring rarely occurs if the mollusca are left to go away on their own.
Some people request treatment if the rash is unsightly
The most common treatment is to squeeze each molluscum between fingernails, or with forceps or tweezers. The aim is to squeeze out the central plug of each molluscum. This can be done by a doctor or nurse. However, you may prefer to do this yourself. There is a good chance that a molluscum will go within 2-4 weeks after being firmly squeezed.
If you do try squeezing treatment at home:
- If you squeeze by using fingernails, ideally, do it whist wearing rubber or latex gloves to avoid spread of the virus. Wash your hands before and after squeezing.
- It is best to squeeze mollusca after a bath, when they are softer.
- Limit to a few mollusca at any one time.
- Wipe up carefully and throw away the white curd-like material that comes from the centre of each molluscum, as it contains infective virus.
- If you use forceps or tweezers then sterilise them afterwards by putting them in boiling water or antiseptic.
In some cases, other treatment options that may be considered by a GP, nurse or hospital specialist (not to be tried at home!) include:
- Freezing treatment with liquid nitrogen. Freezing can destroy the mollusca.
- A hot metal stick (diathermy) to burn off mollusca.
- Scraping the mollusca off with a special instrument called a curette.
- Touching the mollusca with various chemicals such as phenol (a strong acid). This aims to chemically burn and destroy the mollusca.
- Blasting the mollusca with laser beams.
These treatments can be painful, although local anaesthetic may be used before some types of treatment.
Further reading & references
|Original Author: Dr Tim Kenny||Current Version: Dr Laurence Knott|
|Last Checked: 25/11/2010||Document ID: 8704 Version: 2||© EMIS|
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