An Update on the Clinical Management of Cutaneous Molluscum Contagiosum

Harrison P. Nguyen, BA; Stephen K. Tyring, MD, PhD, MBA


Skin Therapy Letter. 2014;19(2) 

In This Article


Molluscum contagiosum is a cutaneous viral infection that is commonly observed in both healthy and immunocompromised children. The infection is caused by a member of the Poxviridae family, the molluscum contagiosum virus (MCV). Molluscum contagiosum presents as single or multiple small white or flesh-colored papules that typically have a central umbilication. The central umbilication may be difficult to observe in young children and, instead, may bear an appearance similar to an acneiform eruption. The lesions vary in size (from 1 mm to 1 cm in diameter) and are painless, although a subset of patients report pruritus in the area of infection.[1] On average, 11–20 papules appear on the body during the course of infection and generally remains a self-limiting disease. However, in immunosuppressed patients, molluscum contagiosum can be a severe infection with hundreds of lesions developing on the body. Extensive eruption is indicative of an advanced immunodeficiency state.

Eruption of molluscum contagiosum usually begins in a localized area of the skin, though the infection can be transmitted to other regions of the body – such as genital, perineal, pubic, and surrounding skin – through autoinoculation. Since MCV can be sexually transmitted, child abuse should be considered when the genital or perineal areas are infected, but autoinoculation is usually the most common source of genital infection.[2] Most cases of sexually transmitted molluscum manifest as papules localized exclusively to the genital area. A 2010 Spanish study reported that sexually transmitted molluscum contagiosum had increased three-fold in its regional hospital from 1987 to 2007.[3] Rarely, molluscum contagiosum can also spread to the oral region – potentially from the genitalia during oral sex – as well as to the conjunctiva and cornea.[4,5] The latter scenario may result in chronic conjunctivitis or superficial punctate keratitis, which complicates the treatment of lesions in the orbital region. In atopic patients, eczema can develop around the papules approximately a month after onset. The eczema, which has also been observed in non-atopic children, occurs in upwards of 30% of patients and, importantly, increases the risk of autoinoculation since patients are more likely to scratch the eczematous region, spreading the viral particles to other areas of the body.[6] The chronic conjunctivitis and eczema associated with molluscum contagiosum subside spontaneously when the lesions are eradicated. Pre-existing eczema may also predispose children to the infection; 62% of children with molluscum contagiosum in Australia reported a history of eczema.[7]

MCV is transmitted through close physical contact with an infected individual or with a fomite.[8] There were an estimated 280,000 patient visits per year for molluscum contagiosum in the United States alone during the 1990s.[9] While the data is limited, several studies have estimated the worldwide prevalence to be between 5% and 7.5% of children, but the number increases to 5%-18% within the human immunodeficiency virus (HIV) positive population and even reaches 30% among acquired immunodeficiency syndrome (AIDS) patients with a CD4+ count under 100/mL.[10–12] The infection is also observed at a higher frequency in certain geographic areas with tropical climates– such as Congo, Fiji, and Papua New Guinea – where the incidence can approach 20% in all children.[13] It is not known whether this increased prevalence is due to a founder effect-associated genetic susceptibility of these populations to MCV infection or whether MCV becomes more virulent in tropical conditions.

Infection in immunocompetent patients is generally self-limiting and resolves on its own within 6 to 9 months. One study reported spontaneous resolution in 94.5% of patients within 6.5 months after initial infection; moreover, the same study reported that 23% of study participants were cured within one month after the first consultation with a dermatologist.[14] It must be emphasized that spontaneous resolution primarily occurs in immunocompetent patients. In contrast, individuals with suppressed immune systems often suffer an increasing degree of recalcitrant molluscum contagiosum that is directly correlated with the level of immunodeficiency.