Warts are sharply defined, benign skin growths of various shapes that have a rough, scaly surface. The trigger for warts is a contagious virus (human papilloma virus, HPV), whereby over 100 different subtypes of this virus are known, all of which can cause warts on the skin and mucous membranes. Some subtypes are also thought to be involved in the development of cervical cancer.
Warts can be divided into groups according to their appearance and place of origin. They occur on different areas of the skin, depending on which subtype of the virus they are caused by. The most common type of wart is the common wart (verrucae vulgares), which occurs mainly in children and adolescents (rarely in adults) on the hands and feet. This type of wart is a nuisance, but it is not usually dangerous.
Another type of wart is the genital wart (genital wart), which is transmitted during sexual intercourse and is much more contagious.
The so-called dell wart (Mollusca contagiosa) does not belong to the group of warts, as it is triggered by a different group of viruses. Their appearance also differs from the classic warts: their size is one to five millimetres. They are bright red in color and have a pearl-like appearance. Their name is derived from the central dent that the larger nodules have. Hence the name dell warts (mollusks).