Warts:
Skin growths caused by viral infections

Warts are benign skin growths that can occur in various forms and on different parts of the body. In most cases, the growths in the uppermost layer of skin are caused by an infection with human papillomaviruses (HPV). Warts are rarely dangerous, but they can cause very unpleasant symptoms and severe pain. There is also a high risk of infection.

Warzen behandeln

Viral warts.
Causes and risk factors.

Most warts are caused by human papillomaviruses (HPV). There are around one hundred HPV subtypes that can cause different warts. If the pathogen gets onto the skin, it can penetrate skin cells through tiny cracks and injuries and multiply there undisturbed.

However, not everyone who has been infected with the virus subsequently develops these troublesome growths in the uppermost layer of skin. Children and adolescents are at increased risk because their immune system is not yet fully developed and therefore cannot fend off the virus. Estimates suggest that this affects one in three children between the ages of four and 12.

In addition, other factors promote the occurrence of warts in children and adults:

  • Increased sweating (hyperhidrosis) and heavy foot perspiration
  • Atopic conditions such as atopic dermatitis (eczema)
  • Diabetes
  • Weakened immune system after serious illnesses
  • Emotional conflicts and stress
  • Smoking

People who often use communal showers at the gym or swimming pool, or who work in meat processing, are also particularly likely to become infected.

Different types of warts.
Different symptoms.

Depending on which virus type causes the infection and which region of the body it settles in, different types of warts develop on the skin.

Common warts.
Verrucae vulgares.

So-called common warts, also known as spiny warts, are the most common form of viral warts. These pinhead- to pea-sized growths are usually scaly and rough. Over time, they take on a dirty yellow colour. Those affected are therefore often reminded of cauliflower. Warts can form anywhere on the body, but they most commonly occur in larger numbers on the hands and feet, as well as on the finger under the nail plate. Common warts generally cause neither itching nor pain. Although they are unsightly, they heal on their own and do not necessarily need to be treated.

Filiform warts.
Verrucae filiformes.

Filiform warts are a special form of common warts, characterised by a long, brush-like stalk. They usually occur in older people on the neck or nose, lips and eyelids. Filiform warts are occasionally accompanied by itching. However, they are primarily perceived as visually bothersome and are therefore removed by a doctor.

Plantar warts.
Verrucae plantares.

Plantar warts do not form raised growths; instead, they grow inward. They generally occur on the sole of the foot. Body weight presses the warts into the subcutaneous tissue when standing and walking, which can be very painful. Most people become infected with plantar warts when walking barefoot in swimming pools, gyms or communal showers.

Verrucae plantares also include mosaic warts. Unlike plantar warts, they cause little or no discomfort. The pinhead-sized growths are located under the toes or on the ball of the foot, and they often also occur over a large area across the entire sole.

Flat warts.
Verrucae planae juveniles.

Flat warts are only slightly raised and sometimes slightly brownish. They occur mainly on the forehead and cheeks, and sometimes on the hands and forearms. Flat warts are also called juveniles because children and adolescents are particularly often affected. If they scratch the warts open, the viruses are spread by the fingernails and new flat warts form. The growths are harmless and disappear on their own.

Molluscum contagiosum.
Mollusca contagiosa.

Molluscum contagiosum is not triggered by human papillomaviruses, but by the molluscum contagiosum virus. The skin nodules are harmless and either affect one or two areas of skin in groups or spread loosely over the entire body. In adults, molluscum contagiosum usually occurs in the genital area; in children, it also occurs on the face and neck or under the armpits.

Molluscum contagiosum can be recognised by its smooth, shiny surface. The papules are white or transparent and contain an infectious secretion. If you come into contact with it, you can easily become infected. Especially when the skin is softened—for example when visiting a swimming pool or sauna—the viruses can penetrate easily. This also applies to fungal skin infections or open wounds.

Preventing warts.
Avoid infection.

Warts are viral skin infections and highly contagious. To prevent other people from becoming infected with the virus, the following measures are recommended:

  • Do not share towels, washcloths, shoes, socks or other textiles and personal care items with others.
  • Machine-wash textiles that come into contact with the warts at at least 60°C.
  • Do not walk barefoot in swimming pools, saunas, changing rooms or communal showers.
  • When swimming, cover warts with a waterproof plaster.
  • Do not touch warts.

To prevent the growths from spreading further on your own skin, do not scratch them and wash your hands thoroughly after each contact with the wart. If you have warts on your feet, it is advisable to change your socks at least daily and keep your feet as dry as possible.

What helps?
Treating warts.

¹In most cases, warts can be treated by using special solutions, creams and plasters, or by freezing.

Common and flat warts, as well as individual plantar warts, can be treated with medicines based on salicylic acid or lactic acid. The solution or cream is applied to the wart several times a day over a period of several weeks to gradually dissolve the horny layer; a suitable plaster remains on the skin for several days. These products are usually available over the counter at pharmacies; before first use, you should read the package leaflet carefully.

For the care and protection of wart-prone skin, creams containing the microalgae active ingredient Spiralin® have also proven effective. Extracted and processed in a complex procedure from microalgae of the genus Spirulina platensis, this ingredient in suitable formulations has a pronounced inhibitory effect against skin-damaging viruses.¹ Creams containing the microalgae active ingredient Spiralin® can be combined with conventional methods of wart treatment.

1 Prof. Dr. Kristian Reich: Cosmetic Medicine, Volume 32, 2011, Issue 2.11

Freezing, in which liquid nitrogen is applied, is generally performed by a doctor. Evaporation creates extreme cold that destroys the cells in the uppermost layer of skin. Cryotherapy is repeated several times, with at least one week between treatments.

Over-the-counter freezing pens for self-treatment are now also available in pharmacies. However, their effectiveness has not yet been scientifically proven. In addition, freezing is not suitable for everyone and should not be done without consulting a doctor.

You ask.
Experts answer.

Warts

Treatment with special medicines containing salicylic acid to soften the hardened layers of skin is considered an effective therapy for removing various types of warts; however, viruses may remain and warts may therefore form again. You can discuss with your dermatologist which treatment method is suitable in your individual case.

Treatment with liquid nitrogen may cause a brief stinging pain. Subsequently, the skin may become red or a blister may form. In individual cases, a small scar may develop, which, however, is usually barely visible after some time.

Vaccination can protect against infection with certain HPV types. Depending on the vaccine, this not only reduces the risk of cervical cancer and other cancers in the genital area, but also prevents genital warts. However, the vaccination does not prevent other types of warts such as common warts, plane warts, or plantar warts on the soles of the feet, which are caused by human papillomaviruses.

These may be seborrheic keratoses, also known as age warts or senile warts. This type of wart is not caused by viruses and is not contagious. These skin nodules get their name because they primarily occur in older age. To rule out any serious skin conditions, you should consult your dermatologist as soon as possible to have the skin changes examined.