Контагіозний молюск (МКХ-10: B08) ⚠️

Molluscum Contagiosum: A Common Viral Skin Condition

Overview

Molluscum contagiosum (MC) is a harmless viral skin infection caused by the molluscum contagiosum virus (MCV), which belongs to the Poxviridae family. It shows up as small, raised, dome-shaped spots that often have a tiny dimple or indentation in the centre. While it’s usually not dangerous, MC is contagious and can spread through direct skin contact or by touching contaminated items. This makes it a concern in places like schools, gyms, and swimming pools.

MC mostly affects children and teenagers, but adults can get it too—especially those with weakened immune systems or ongoing skin conditions. The spots are generally painless and clear up on their own, but they can cause cosmetic worries, itching, and social discomfort, which often leads people to seek treatment.

In healthy individuals, the infection usually resolves by itself within 6 to 12 months. However, treatment is often advised to reduce the chance of spreading the virus, passing it to others, and dealing with persistent or recurring spots.

What Causes It and How It Spreads

Molluscum contagiosum spreads when the virus gets directly into the skin. It can be passed on through skin-to-skin contact or by touching objects like towels, clothes, or shared bathwater that have the virus on them. Common ways it spreads include:

Contact in childhood: Sharing toys, towels, gym mats, or being in swimming pools;
Sexual transmission: In adults, MC can spread during close or sexual contact, with spots usually appearing around the genitals or pubic area;
Self-spread: Scratching or rubbing the spots can move the virus to other parts of the body.

Some factors that make catching molluscum contagiosum more likely are:

Weakened immune system: Conditions like HIV/AIDS, cancer, or taking medications that suppress immunity;
Poor hygiene or living in crowded places;
Chronic skin issues: Conditions like eczema or atopic dermatitis can let the virus enter through damaged skin;
Regular exposure to shared spaces such as public pools, changing rooms, or daycare centres.

In children, spots usually appear on the face and limbs, while in adults, they’re more common around the genitals and lower tummy, reflecting how the virus is passed on.

How Molluscum Contagiosum Is Diagnosed

Doctors usually diagnose MC by looking at the spots during a physical exam. The lesions are quite distinctive—small, firm, pink or skin-coloured bumps with a typical central dimple. In most cases, diagnosis is straightforward.

Sometimes, especially in unusual cases or if the person has a weak immune system, further tests might be needed to rule out other conditions. These can include:

Dermatoscopy: A close-up look at the spots showing round or oval whitish areas with a central keratin plug and brain-like patterns;
Biopsy and lab analysis: Taking a small skin sample if cancer is suspected or if spots don’t respond to treatment. Under the microscope, large pink inclusion bodies (called molluscum bodies) are seen inside skin cells;
PCR testing or viral culture: Rarely done because MC is harmless, but may be used in research or severe cases.

Symptoms: What Molluscum Contagiosum Looks Like

Molluscum contagiosum shows up as one or more round, dome-shaped bumps about 2–5 mm across. Each bump has a little dip in the middle and may contain a waxy, white core. If you gently squeeze a spot, it might release a soft, cheese-like substance made up of virus particles and skin debris.

Key features include:

Colour: Skin-toned, pink, or pearly white;
Surface: Smooth and shiny, without flakes or crusts;
Central dimple: Often filled with a whitish keratin plug;
Itching or irritation: Sometimes present, especially while healing or in sensitive skin;
Location: In children—face, body, arms, and legs; in adults—lower tummy, groin, genitals, and thighs;
Number of spots: Can be just a few or several dozen; if untreated, they may cluster together.

Usually, the spots don’t cause pain but can lead to emotional distress because they’re visible and contagious. Sometimes, scratching or injury can cause a secondary bacterial infection.

What Dermatoscopy Shows in Molluscum Contagiosum

Dermatoscopy is a tool that gives a detailed view of MC spots, which helps when the diagnosis isn’t clear.

Typical findings include:

Milky-white round or oval shapes with clear edges;
A central blurry area that’s the keratin plug (a yellow-white core made of many small globules);
Brain-like or lobed patterns inside the spot;
Radial lines around the edges that look dotted or wavy, forming a crown-like pattern.

These features help tell MC apart from warts, moles, and skin tumours, guiding treatment when the diagnosis is uncertain.

Other Conditions That Can Look Like Molluscum Contagiosum

Some harmless and serious skin conditions can look similar to MC, so it’s important to rule these out:

Viral warts: Usually don’t have a central dimple and have a rough, thickened surface;
Papillomatous nevus: More pigmented and textured than MC;
Nevus sebaceous: Often appears in babies or young children, usually on the scalp;
Dermatofibroma: Firm, pigmented bumps with a dimple when pinched, but no central core;
Keratoacanthoma: Fast-growing dome-shaped lumps with a central keratin plug, mostly in older adults;
Basal cell carcinoma (nodular type): Pearly lumps with visible small blood vessels and sometimes ulcers;
Amelanotic melanoma: Non-pigmented, irregular lumps that grow quickly and need a biopsy to confirm.

Risks and Why It Matters

From a cancer perspective, molluscum contagiosum is not cancerous and doesn’t increase cancer risk. The virus stays in the top layer of skin and doesn’t spread deeper or to internal organs.

Still, there are some concerns:

Highly contagious: Easily spreads through skin contact or contaminated surfaces;
Cosmetic impact: Especially if spots are numerous or on the face or genitals;
Self-spread risk: Scratching can spread the virus to other areas;
Secondary infections: Bacterial infections can develop if spots are scratched or damaged;
Immune system links: Widespread or long-lasting MC might indicate an underlying immune problem.

If spots suddenly grow quickly, change texture, or cause pain, a biopsy might be needed to rule out cancer or other skin diseases.

When to See a Doctor

Treatment is usually recommended to stop the virus spreading, avoid complications, and ease cosmetic worries. You should see a dermatologist if:

Spots are increasing in number or size;
There’s bleeding, injury, or signs of infection around the spots;
Spots are on sensitive areas like the face, genitals, or eyelids;
You have a weakened immune system or chronic skin problems.

If you decide not to have treatment right away, regular check-ups with photos and skin mapping can help track any changes.

Treating Molluscum Contagiosum

There are several ways to treat MC, depending on your age, immune health, where the spots are, and your preferences. Common treatments include:

Laser therapy: CO₂ laser removes spots precisely and reduces scarring;
Cryotherapy: Freezing spots with liquid nitrogen to destroy them;
Electrocoagulation or curettage: Physically removing spots under local anaesthetic, often used in adults;
Radiofrequency ablation: Good for multiple clustered spots with minimal skin damage;
Topical treatments: Such as cantharidin, imiquimod, retinoids, or potassium hydroxide, used under medical supervision.

In rare cases, surgery and lab analysis are needed if spots look unusual, don’t clear up, or cause diagnostic uncertainty.

Removing spots yourself is not advised because it can spread the virus, cause scarring, bleeding, and infections. Treatment is considered successful when all visible spots have gone, but new ones can still appear, so follow-up is important.

Preventing Molluscum Contagiosum

Prevention focuses on avoiding skin damage, keeping good hygiene, and stopping the virus spreading in shared spaces.

Key tips include:

Avoid skin contact with infected people and don’t share personal items like towels;
Limit sun exposure and use sunscreen to protect your skin;
Prevent skin damage by avoiding harsh scrubbing or strong exfoliants;
Use protection during intimate contact if spots are on the genitals;
Treat other infections promptly to keep your immune system strong;
Have regular skin checks if you have chronic skin conditions or a weakened immune system.

With early diagnosis, proper treatment, and good advice, molluscum contagiosum can be managed well, reducing the chance of spreading or coming back.