Warts are small, rough growths on the skin caused by a virus. They are extremely common in children and represent a benign infection of the skin’s top layer. Warts most frequently appear on the hands and feet. They are noncancerous and often resolve on their own, but they can be a source of discomfort or embarrassment.
The Cause and Contagion
Warts are caused by the Human Papillomavirus (HPV), a family of over 100 different viruses. The specific strains causing common skin warts are typically different from those linked to genital warts or cancers. The virus enters the skin through tiny cuts or scrapes, causing an overgrowth of cells that results in the characteristic bumpy appearance.
Warts are contagious and spread easily through both direct and indirect contact. Direct transmission occurs through skin-to-skin contact with an infected person or by touching an existing wart. Indirect transmission happens when the virus is picked up from contaminated surfaces, such as shared towels or public areas like pool decks.
Children are more susceptible to the virus than adults due to frequent minor skin injuries and developing immune systems. The virus needs a break in the skin barrier to establish an infection, which is why warts often cluster around areas like the knees and hands. The incubation period can be long, sometimes taking months or years for a wart to become visible.
Common Types and Locations on Children
The appearance of a wart depends on the specific HPV strain and its location. Common warts (verruca vulgaris) are the most frequent type, often appearing on the fingers, hands, elbows, and knees. These are rough, dome-shaped growths that may be grayish-yellow or brown, sometimes resembling a tiny cauliflower. They may feature small black dots, which are clotted blood vessels.
Plantar warts develop on the soles of the feet. Pressure from walking causes them to grow inward, making them flatter than common warts. They can be painful, often feeling like walking on a small stone, and may appear as a cluster called mosaic warts. Flat warts (verruca plana) are smaller, smoother, and only slightly raised, often presenting in large groups on children’s faces, arms, or legs.
Treatment Options and When to Seek Medical Help
Many warts eventually disappear without intervention, a process that can take months or years as the child’s immune system fights the virus. Treatment is recommended if the wart is painful, interferes with daily activities, is rapidly spreading, or causes significant self-consciousness.
The most common over-the-counter (OTC) treatment uses salicylic acid, which slowly peels away the infected skin layers. These treatments are available as patches, gels, or liquids and require consistent use for several weeks or months. Apply the product only to the wart itself to avoid irritating the surrounding healthy skin.
If OTC treatments fail, a pediatrician or dermatologist can offer professional options. Cryotherapy, which involves freezing the wart with liquid nitrogen, is a common procedure that causes the tissue to blister and fall off. Other professional methods include prescription topical treatments, such as cantharidin, which forms a blister beneath the wart, or stronger acid preparations.
Parents should contact a doctor if the wart is painful, bleeds easily, shows signs of infection (like redness or pus), or is rapidly growing or spreading. Medical attention is also necessary for warts located on the face or genitals, or if the child has a compromised immune system or diabetes. Proper identification and management can prevent spreading and minimize discomfort.