Molluscum Contagiosum: Symptoms, Causes, Prevention & Treatment

Highly contagious viral infection of the skin caused by a virus of poxvirus family called “molluscum contagiosum.” It is also sometimes called water warts. This virus causes typical small bumps or lesions on the upper layer of the skin.

These bumps are painless though in some cases they may be itchy. There may be one such lesion or few lesions. Genital areas, arms, legs, abdomen, neck, or face are most commonly affected.

Although in most cases there would be only a few localized lesions, however, in immune-compromised individuals, lesions may be widespread. In most cases, these lesions would disappear by themselves within a year without any treatment or leaving a scar.

It is a highly contagious virus that spreads due to either direct contact with someone having this infection or because of sharing contaminated objects. Thus, it may spread through a shared towel or other clothing. In adults, it may also spread due to sexual contact.

This infection commonly affects kids aged 1-12 years old (1). The disease is less common among adults as many of them have developed immunity against it. Nonetheless, in some adults, it may spread aggressively, especially in those with weakened immunity due to HIV or cancer treatment.

Figure 1: Typical lesion caused by molluscum contagiosum
source: openwiki.kr

Symptoms of Molluscum Contagiosum

It may not always be possible to verify the time of contacting the infection due to the very long incubation period. There is very little known about it, but symptoms of molluscum contagiosum may occur anywhere after 2 weeks to 6 months after first contact (2).

Apart from immunocompromised people, those living with atopic dermatitis are also at higher risk of the disease due to breakage of the upper layer of the skin (3).

In most cases, you would see small, painless, bumps on the skin. There may be either a single bump or multiple bumps. However, a number of bumps would rarely be more than 10-20, unless the person has a week immunity.

These bumps will be smooth and shiny with some of them having a dimple in the middle. The color of bumps may be pale, flesh-colored, or white, or pink. Bumps will be anywhere between 2-5 mm. Larger bumps are only present in people with very low immunity.

Causes of Molluscum Contagiosum

As already mentioned, it is a viral infection caused by a virus called molluscum contagiosum. There are two ways to get this infection either my coming in direct contact with someone carrying an infection, or sharing contaminated objects.

The risk is higher in those with weak immunity, skin diseases. Some people are genetically more prone to get infected with this virus due to certain immune defects (like those with DOCK8 deficiency) (4).

Generally, infection with molluscum contagiosum is limited to one site in most individuals. However, one should not break bumps with nails or in other ways at home. It is also important to tell children not to touch these bumps.

These bumps are like colonies of the virus, if they break, they release lots of viruses and infection may spread to other parts of the body.

Diagnosis of molluscum contagiosum is mainly based on physical examination. A dermatologist would not have any problem in identifying the lesions. There is no specific blood test for it, although in rare cases a biopsy may be needed to determine the cause of these bumps.

Preventing the infection

Since virus spreads through contact, good hygiene is vital in preventing its spread. The virus can only grow inside the upper layer of the skin; it means that once the lesions are gone, so has the virus. It means that a person without lesions cannot spread the infection.

Simple hygienic measures like washing hands may help prevent the spread of the virus. The virus needs time to penetrate the skin; timely washing may help remove it from the surface.

If someone is infected with it at home, then make sure not to share objects with that person. Similarly, siblings should be discouraged from bathing together.

If you or your child have contracted an infection, and you can see the lesions than make sure not to touch those lesions. Touching or pricking the lesions may only spread the germs. The best thing that anyone can do at home is to cover the lesion with a bandage or special plaster, this way risk of spreading the virus will be minimized.

Treating molluscum contagiosum

Although you may feel like breaking or pricking these bumps, it must be avoided, as in that way you will only make things worse and spread the infection. Treatment is better done in consultation with a specialist who may either remove or destroy these lesions or try to treat them with some medications.

Some of the treatments for molluscum contagiosum are (4):

• Physical removal of lesions – the technique of doing so may vary from clinic to clinic. Some specialist may scrape away with a curette; others may use cryotherapy (destroying with the help of liquid nitrogen). Laser, electron beam, photodynamic therapy are some other ways of deactivating the lesion.
• Chemical destruction of lesion – is another way to get rid of it. A specialist may either use phenol 10% or Trichloroacetic acid 100% to burn these lesions.
• Non-destructive topical agents – are not corrosive chemicals, they will not burn the lesion and will take more time to destroy the virus. One may apply solutions or creams based on cantharidin, podophyllotoxin, salicylic acid, retinoic acid, and so on.
• Immune modulators– help the immune system to destroy the virus aggressively, such medication may be either taken orally (like cimetidine) or applied to the lesion (imiquimod, candida antigen, diphencyprone).
• Antiviral drugs– are reserved for difficult to treat conditions or for recurrent infections. The doctor may either prescribe Cidofovir cream or in severe cases may recommend Cidofovir intravenously.

Such a treatment will be done for at least 2 weeks and may be repeated if necessary.

When it comes to treatment, physical removal or chemical destructions would be methods of choice in most cases, and they will work. Other ways are reserved for more specific situations.

References

1. Brown J, Janniger CK, Schwartz RA, Silverberg NB. Childhood molluscum contagiosum. Int J Dermatol. 2006;45(2):93–9.
2. Clinical Information | Molluscum Contagiosum | Pox viruses | CDC [Internet]. 2018 [cited 2019 Jan 11]. Available from: https://www.cdc.gov/poxvirus/molluscum-contagiosum/clinical_information.html
3. Osio A, Deslandes E, Saada V, Morel P, Guibal F. Clinical Characteristics of Molluscum Contagiosum in Children in a Private Dermatology Practice in the Greater Paris Area, France: A Prospective Study in 661 Patients. Dermatology. 2011;222(4):314–20.
4. Chen X, Anstey AV, Bugert JJ. Molluscum contagiosum virus infection. Lancet Infect Dis. 2013 Oct 1;13(10):877–88.