There are several types of wart and verruca, which may require treatment or can disappear on their own.
Warts and verrucas are small, non-cancerous growths within the skin caused by the human papilloma virus.
Warts may occur on their own or in clusters. There are many different types including:
Common warts. These raised growths, which have a hard, uneven surface, are the most familiar type of wart and usually appear on the hands and feet.
Plantar warts, known as verrucas. These are warts on the soles of the feet that have been pushed into the skin surface by the weight of the body.
Plane warts. These are smaller and flatter, and mostly occur on the hands or face.
They're caused by a viral infection in the skin cells. The virus is called the human papilloma virus (HPV) - there are more than 100 types of HPV.
Warts are common and all children are vulnerable, but children with immune system problems may have an increased risk. The virus is present throughout the environment and is infectious, but the risk of catching them from public places is now debatable.
Each wart forms a small lump, but sometimes multiple warts fuse together to form a mosaic. Common warts are rarely painful, but plane warts may be itchy.
Verrucas form round areas in the skin, often with a central dark spot. They may be painful when pressure is applied.
Diagnosis and treatment Most warts disappear without treatment after a few months or years - 20 per cent of growths disappear within three months. Their duration is influenced by changes in the body's resistance to the HPV virus.
Warts and verrucas only need treatment if they're painful or are a cosmetic problem. A number of treatments can be applied at home, including a combination of salicylic acid paint and rubbing with a pumice stone or foot scraper. Stronger treatments can be obtained from a chiropodist or doctor.