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FACT SHEET: Molluscum Contagiosum (also known as “water warts” and “MC”; caused by the molluscum contagiosum pox virus, which infects only humans)

Date of Publication: May 19, 2015
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Is the initiation of non-invasive dental hygiene procedures* contra-indicated?

  • No, unless there are active oral lesions. 

Is medical consult advised?  

  • Yes, if the diagnosis is uncertain and/or the patient/client is not already under medical care. While MC is self-limited in healthy persons (often requiring no treatment), underlying atopic disease, lesion visibility, and the desire to prevent transmission may prompt medical intervention (e.g., cryosurgery, curettage, laser therapy, topical therapy, or oral cimetidine).

Is the initiation of invasive dental hygiene procedures contra-indicated?**

  • No, unless there are active oral lesions.

Is medical consult advised? 

  • See above. 

Is medical clearance required? 

  • No.

Is antibiotic prophylaxis required?  

  • No.

Is postponing treatment advised?

  • Not usually, unless there are oral (unusual) or perioral lesions;  in such cases, treatment should be postponed until the MC lesions have resolved. Covering MC bumps with clothing or bandages can minimize viral transmission from lesions elsewhere on the patient/client’s body. Avoid touching molluscum lesions. 

Oral management implications

  • Mode of transmission is usually through direct contact. Transmission can be nonsexual (skin-to-skin contact with a person who has an MC papule, and via fomites, such as virus-laden towels, clothes, and toys) or sexual (via oral, anal, vaginal, or skin-to-skin contact). Autoinoculation can also occur. Lesions may appear 7 days to 6 months after exposure (typically 2 to 6 weeks). The period of communicability is likely as long as lesions persist; without treatment1, the papules usually disappear spontaneously within 6 to 12 months, but may take as long as 4 years to resolve. Any one lesion typically has a lifespan of 2 to 3 months.
  • There is no Canadian licensed molluscum contagiosum vaccine. Preventive measures consist of avoiding contact with papules on affected persons, as well as their fomites (i.e., contaminated objects such as towels, sponges, toys, etc.).
  • Once MC bumps have resolved, there is no risk of virus transmission. However, persons can be re-infected; i.e., life-long immunity is not conferred by prior infection. 
  • Lesions that are covered by clothing (e.g., on the trunk or limbs) pose little risk of transmission to others. However, dental hygienists are at risk of acquiring MC from facial, perioral, and intraoral lesions of affected patients/clients.
  • Dental hygienists with MC lesions on their hands should avoid patient/client contact.

Oral manifestations

  • Primarily a skin infection, molluscum contagiosum lesions can also occur on mucous membranes, although involvement of the oral soft tissues is uncommon.
  • Oral lesions occur most frequently on the lips, tongue, and buccal mucosa. Their appearance is similar to lesions on the skin (see below).
  • Facial and perioral MC is seen with increased frequency in human immunodeficiency virus infection, particularly in HIV-infected homosexual men. Low CD4 counts have been linked to widespread facial mollusca, which therefore have become a marker for severe HIV disease.

Related signs and symptoms

  • Most cases of molluscum contagiosum occur in children over 1 year of age.  Although often seen in Canada, MC is particularly common in developing countries.
  • MC is a generally benign, superficial skin disease, characterized by small, skin-coloured to white, pearly papules with a central dimple. The lesions average 2 to 5 mm in size, and a white cheesy material may sometimes be expressed from the core. The bumps can occur anywhere on the skin, except for the palms and soles.
  • MC lesions are generally painless, but they may itch or become irritated. Picking or scratching the bumps may lead to further MC infection (autoinoculation), scarring, or secondary bacterial infection. In about 10% of cases, eczema develops around the lesions. 
  • MC lesions are classified in one of three ways: the commonly seen skin papules found primarily on the face, trunks, and upper limbs of children; the sexually transmitted lesions found on the lower abdomen, inner thighs, buttocks, and genitals of sexually active adults; and the diffuse, very large (≥15 mm in diameter), treatment-resistant eruptions of patients/clients with AIDS or other immunosuppressive disorders.
  • Atopic dermatitis (with barrier breaks and skin immune cell dysfunction) may be a risk factor for contracting MC.

References and sources of more detailed information


Date: December 28, 2014
Revised: March 31, 2020


FOOTNOTES

1 Treatment may be indicated in immunocompromised persons and/or to reduce risk of transmission. Therapies fall into 3 main categories: ablative (cryotherapy, curettage, laser therapy, salicylic acid, trichloroacetic acid, cantharidin, and podophyllotoxin); immunomodulatory (imiquimod, cimetidine); and virucidal (topical cidofovir).


* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.