Molluscum Contagiosum: Symptoms, Causes & Treatment

What Is Molluscum Contagiosum?

Molluscum contagiosum is a viral skin infection caused by the molluscum contagiosum virus (MCV), a member of the poxvirus family. It produces characteristic small, round, flesh-colored bumps on the skin that are painless but may itch. The infection is benign and self-limiting, meaning it resolves on its own without treatment in most cases.

Molluscum contagiosum is one of the most common viral skin infections in children worldwide, affecting an estimated 5-10% of children at some point during childhood. The infection is caused by the molluscum contagiosum virus (MCV), which belongs to the poxvirus family. This virus only infects the top layers of the skin and does not spread to other parts of the body or cause systemic illness.

The name "molluscum" comes from the Latin word meaning "soft," which describes the appearance of the lesions. While the bumps are sometimes called "water warts," they are not actually warts and are caused by a different type of virus than common warts (which are caused by human papillomavirus, or HPV).

Although molluscum contagiosum is most commonly seen in young children between the ages of 1 and 10 years, it can affect people of any age. In adults, the infection is often transmitted through sexual contact and tends to appear in the genital area, though it is not classified as a sexually transmitted infection (STI). People with weakened immune systems, such as those with HIV/AIDS or those taking immunosuppressive medications, may experience more severe or widespread infections.

Why do children get molluscum contagiosum?

Children are particularly susceptible to molluscum contagiosum for several reasons. Their immune systems are still developing and may not mount as effective a response to the virus as adult immune systems. Children also tend to have more frequent close physical contact with other children during play, sports, and other activities, which facilitates transmission. Additionally, children with atopic dermatitis (eczema) have a higher risk of developing molluscum contagiosum because their skin barrier is compromised, making it easier for the virus to establish infection.

The virus can remain dormant in the skin for weeks to months before visible bumps appear, which is why outbreaks sometimes seem to occur without any obvious source of infection. Once the immune system learns to recognize and fight the virus, the infection typically clears completely, and most people develop some degree of immunity to prevent future infections.

What Are the Symptoms of Molluscum Contagiosum?

The main symptom of molluscum contagiosum is the appearance of small, round, dome-shaped bumps on the skin. These bumps are typically 2-5 millimeters in diameter, have a central dimple or pit (called umbilication), and are flesh-colored or slightly pink. They are usually painless but may itch, especially in children with eczema.

Molluscum contagiosum presents with distinctive skin lesions that are usually easy to recognize once you know what to look for. The bumps typically appear anywhere from 2 weeks to 6 months after exposure to the virus, though the incubation period can vary widely. Understanding the characteristic features of these lesions helps parents identify the condition and know what to expect.

The lesions of molluscum contagiosum have several distinctive features. They are small, round, and dome-shaped, typically measuring 2-5 millimeters in diameter, though they can occasionally grow larger (up to 10-15 mm) in some cases. Each bump has a characteristic central indentation or dimple, known as umbilication, which is the most distinguishing feature of molluscum lesions. This dimple may contain a small white or waxy core, which is a collection of virus particles mixed with skin cells.

The color of the bumps varies depending on the individual's skin tone. On lighter skin, they typically appear flesh-colored, white, or slightly pink. On darker skin tones, the lesions may appear lighter than the surrounding skin or have a more grayish appearance. The surface of the bumps is usually smooth and shiny, almost pearlescent in quality.

Common locations for molluscum lesions

In children, molluscum contagiosum most commonly appears on the torso (chest, abdomen, and back), arms, face, and neck. The armpits and inner elbow creases are also frequently affected areas. Children can develop anywhere from a few bumps to hundreds of lesions, though most have between 10-30 bumps. The lesions tend to occur in clusters and may appear in a linear pattern if they have spread through scratching.

In sexually active adults, molluscum lesions often appear on the lower abdomen, thighs, groin area, and genitals. The location of lesions can help healthcare providers understand how the infection was likely acquired.

Associated symptoms

While the bumps themselves are typically painless, they may cause some itching in certain individuals. This itching is particularly common in children who also have atopic dermatitis (eczema). It is important to discourage scratching, as this can spread the virus to other areas of the body and increase the risk of secondary bacterial infection.

Some children develop eczema specifically around their molluscum lesions, a condition called molluscum dermatitis. This manifests as redness, dryness, and itching in the skin immediately surrounding the bumps. Molluscum dermatitis is a sign that the immune system is beginning to recognize and respond to the virus, and it often precedes the natural clearing of the lesions.

How Does Molluscum Contagiosum Spread?

Molluscum contagiosum spreads primarily through direct skin-to-skin contact with an infected person. It can also spread indirectly through contact with contaminated objects like towels, clothing, or toys. Additionally, a person can spread the virus to other parts of their own body by touching or scratching the lesions (autoinoculation).

Understanding how molluscum contagiosum spreads is essential for preventing transmission to others and limiting the spread of lesions on an affected individual's body. The molluscum contagiosum virus is exclusively a human pathogen and cannot be transmitted to or from animals.

The primary mode of transmission is direct skin-to-skin contact with an infected person. This can occur during play, sports activities, wrestling, or other close physical contact. The virus is released from the central core of the lesions and can easily transfer to another person's skin during contact. The virus requires some form of skin abrasion or minor break in the skin to establish infection, which is why areas of skin that experience friction or minor trauma are often affected.

Indirect transmission can also occur through contact with contaminated objects, known as fomites. Towels, washcloths, clothing, bath sponges, and toys that have come into contact with molluscum lesions can harbor the virus and transmit it to others. Sharing these items should be avoided to prevent spread. The virus can survive on surfaces for some time, though it is susceptible to standard cleaning and disinfection methods.

Autoinoculation

One of the most important routes of spread is autoinoculation, where an infected person spreads the virus to other parts of their own body by touching or scratching the lesions and then touching uninfected skin. This is why molluscum lesions often appear in clusters or in a linear pattern along scratch lines. Discouraging scratching and keeping fingernails short and clean can help prevent this type of spread.

Children are particularly prone to autoinoculation because they often have difficulty resisting the urge to pick at or scratch itchy lesions. Additionally, activities like bathing can help spread the virus if the infected skin is rubbed or scrubbed vigorously.

Risk factors for transmission

Several factors can increase the risk of acquiring or spreading molluscum contagiosum. Children with atopic dermatitis (eczema) have a significantly higher risk because their compromised skin barrier makes it easier for the virus to establish infection. The virus also tends to spread more easily in warm, humid environments and during activities involving close physical contact.

Swimming pools themselves do not spread molluscum contagiosum (the chlorine kills the virus), but sharing towels, floatation devices, or engaging in close physical contact around pools can facilitate transmission. Similarly, while the water in baths does not spread the virus, sharing bathwater or bath toys can lead to transmission between siblings.

The infection remains contagious as long as the bumps are present. Once all lesions have completely healed, the person is no longer contagious. Having had molluscum contagiosum once provides some degree of immunity, and reinfection is uncommon, though it can occur.

How Is Molluscum Contagiosum Treated?

In most cases, molluscum contagiosum does not require treatment and will resolve on its own within 6-18 months. Treatment may be considered for cosmetic reasons, to prevent spread to others, or if lesions are causing symptoms. Treatment options include topical medications, cryotherapy (freezing), and curettage (scraping), though these can be painful and may cause scarring.

The primary approach to managing molluscum contagiosum in healthy children is watchful waiting, also called expectant management. This means allowing the infection to run its natural course without active intervention. The rationale for this approach is that the infection is harmless, self-limiting, and treatment options often cause more discomfort and potential complications (such as scarring) than the disease itself.

The bumps typically last anywhere from a few months to a year or more before resolving completely. Individual lesions may persist for 2-3 months before the immune system clears them. However, because new lesions can continue to appear while others are healing, the total duration of infection can extend to 18 months or even longer in some cases. Children with eczema or weakened immune systems may have a more prolonged course.

When to consider treatment

While most cases do not require treatment, there are situations where intervention may be considered. These include lesions in cosmetically sensitive areas like the face, lesions that are causing significant itching or discomfort, lesions in the genital area of sexually active individuals, lesions that are becoming secondarily infected, or if there is a strong desire to prevent transmission to others (such as in competitive sports or childcare settings).

Topical treatments

Several topical (applied to the skin) treatments can help speed the resolution of molluscum lesions. Over-the-counter products containing potassium hydroxide (KOH) can be applied directly to the lesions twice daily. These products work by breaking down the protein structure of the lesions. They may cause some skin irritation and should be used according to package directions or as advised by a healthcare provider.

Prescription topical treatments may include tretinoin cream, imiquimod cream, or cantharidin (applied in a medical office). These medications can be effective but may cause skin irritation, blistering, or other side effects. They are generally used for older children and adults rather than young children.

Physical treatments

Cryotherapy involves freezing the lesions with liquid nitrogen, which destroys the infected tissue. This is done in a medical office and may require multiple sessions. Cryotherapy can be painful and may leave temporary or permanent lightening of the skin (hypopigmentation) or scarring.

Curettage involves scraping the lesions with a small, sharp instrument. This can be done under local anesthesia and is effective at removing individual lesions. However, it can be painful, may cause bleeding, and can potentially leave scars.

Treating associated eczema

If eczema develops around molluscum lesions (molluscum dermatitis) or if the child has pre-existing atopic dermatitis, treating the eczema is important. This typically involves regular use of emollients (moisturizers) and may require mild topical corticosteroids (such as hydrocortisone cream, available over the counter) for more significant inflammation. Better-controlled eczema can help reduce itching, prevent scratching, and limit the spread of molluscum to other areas of the skin.

Consult a healthcare provider before using hydrocortisone on children under 2 years of age or if the eczema is widespread or severe.

When Should You See a Doctor?

Most cases of molluscum contagiosum do not require medical attention. You should see a doctor if the lesions become red, swollen, or painful (signs of bacterial infection), if there is extensive eczema around the lesions, if the bumps are on the eyelids and affecting vision, if you are unsure of the diagnosis, or if you want to discuss treatment options.

The vast majority of children with molluscum contagiosum do not need to see a doctor, and the condition can be managed at home with watchful waiting. However, there are certain situations where medical evaluation is warranted.

Secondary bacterial infection is the most common complication of molluscum contagiosum. Signs that a lesion has become infected with bacteria include increased redness around the bump, pus or drainage from the lesion, increased pain or tenderness, warmth in the surrounding skin, and fever. If you notice these signs, the child should be evaluated by a healthcare provider, as antibiotic treatment may be necessary.

If the child has widespread or severe eczema developing around the molluscum lesions, a healthcare provider can recommend appropriate treatments to manage the eczema and reduce discomfort. This is especially important if over-the-counter hydrocortisone is not providing adequate relief.

Molluscum lesions on the eyelids or around the eyes warrant medical attention, as they can potentially affect the eye or eyelashes. An ophthalmologist or dermatologist may need to be involved in the management of periocular lesions.

Seeking care for diagnosis

If you are unsure whether your child's skin bumps are molluscum contagiosum, it is reasonable to seek medical evaluation for a proper diagnosis. While molluscum has a characteristic appearance, other conditions can sometimes look similar, including warts, skin-colored moles, and other viral or bacterial infections. A healthcare provider can usually diagnose molluscum contagiosum by visual examination alone.

If you are interested in discussing treatment options to speed the resolution of the infection, a healthcare provider can explain the available options, their potential benefits, and their risks. This conversation can help you make an informed decision about whether active treatment is right for your child's situation.

How Can You Prevent Molluscum Contagiosum from Spreading?

To prevent molluscum from spreading, avoid scratching or picking at the bumps, do not share towels or personal items, cover lesions with clothing or bandages during activities with close contact, keep fingernails short and clean, wash hands frequently, and treat any associated eczema to reduce itching.

While it is not always possible to prevent molluscum contagiosum entirely, there are several measures that can reduce the risk of spreading the infection to others or to other parts of the body.

Avoiding scratching or picking at the lesions is one of the most important preventive measures. Scratching releases viral particles that can spread to other areas of the skin (autoinoculation) and can also introduce bacteria that cause secondary infections. Keeping fingernails short and clean can help reduce the damage done if scratching does occur.

Personal items that come into contact with the lesions should not be shared with others. This includes towels, washcloths, razors, bar soap, clothing, and bath sponges. Each family member should have their own set of these items when someone in the household has molluscum contagiosum.

During activities

Covering molluscum lesions with clothing or waterproof bandages during activities that involve close physical contact or shared equipment can help reduce transmission risk. This is particularly relevant for sports like wrestling, gymnastics, or swimming where skin contact with others or shared surfaces is common.

Regular handwashing, especially after touching the affected areas of skin, helps prevent spreading the virus to other parts of the body and to other people. Teaching children proper hand hygiene is an important part of managing the infection.

Managing eczema

If your child has atopic dermatitis (eczema), keeping it well-controlled is important for reducing the spread of molluscum. Eczema causes itching that leads to scratching, and the compromised skin barrier makes it easier for the virus to spread. Regular use of emollients, avoiding triggers that worsen eczema, and using appropriate anti-inflammatory treatments as needed can all help.

Can Children with Molluscum Attend School and Activities?

Yes, children with molluscum contagiosum can and should continue to attend school, daycare, and participate in all normal activities including sports and swimming. The infection is harmless, and exclusion is not warranted. Covering visible lesions with clothing or bandages during close-contact activities is a reasonable precaution.

One of the most common concerns parents have when their child is diagnosed with molluscum contagiosum is whether they need to keep them home from school or restrict their activities. The good news is that molluscum contagiosum is not considered a significant public health concern, and children do not need to be excluded from normal activities.

Public health organizations and dermatology associations consistently recommend that children with molluscum contagiosum continue to attend school, daycare, and participate in extracurricular activities. The condition is benign and self-limiting, and the disruption to a child's education and social development caused by exclusion would far outweigh any minimal benefit in terms of reducing transmission.

While it is true that molluscum can spread to other children, this is not a dangerous infection, and all children who acquire it will eventually clear the virus on their own. Attempting to prevent all transmission would be impractical and unnecessary.

Swimming and water activities

Children with molluscum contagiosum can participate in swimming and other water activities. The chlorine in pools kills the virus, so swimming pool water does not transmit the infection. However, transmission can occur through sharing towels, floatation devices, or close physical contact around the pool. Having the child use their own towel and avoiding sharing pool toys is a reasonable precaution.

Sports and physical activities

Participation in sports and physical activities should generally continue. For sports involving significant skin-to-skin contact, such as wrestling or martial arts, covering visible lesions with clothing, tape, or bandages when practical can reduce transmission risk. Some sports organizations may have specific guidelines about skin infections that should be followed.

The key message for parents is that molluscum contagiosum should not significantly limit a child's life or activities. The condition is temporary and harmless, and maintaining normal routines supports the child's overall wellbeing and development.

Can Adults Get Molluscum Contagiosum?

Yes, adults can get molluscum contagiosum, though it is less common than in children. In adults, the infection is often sexually transmitted and tends to appear on the lower abdomen, thighs, and genital area. Adults with weakened immune systems may experience more severe or widespread infections.

While molluscum contagiosum is most commonly seen in young children, adults can also develop the infection. The clinical presentation and course of the disease in adults may differ somewhat from that seen in children.

In sexually active adults, molluscum contagiosum is often transmitted through sexual contact. In these cases, the lesions typically appear on the lower abdomen, inner thighs, genital area, and surrounding skin. It is important to note that while molluscum can be sexually transmitted, it is not classified as a sexually transmitted infection (STI) in the traditional sense, and there are no public health reporting requirements associated with it.

Adults who acquire molluscum through non-sexual routes (such as from contact with infected children) may develop lesions in typical locations similar to those seen in children, such as the arms, torso, and face.

Molluscum in immunocompromised individuals

Adults with weakened immune systems are at particular risk for more severe molluscum contagiosum infections. This includes people living with HIV/AIDS, organ transplant recipients on immunosuppressive medications, and those receiving chemotherapy or other immunosuppressive treatments. In these individuals, molluscum lesions may be more numerous, larger, and more resistant to treatment. The infection may persist for much longer than in healthy individuals and can sometimes be a marker of immune system decline.

For adults with unexplained, extensive, or persistent molluscum contagiosum, evaluation for underlying immune system problems may be warranted.