Health and Medicine

Diseases, Disorders, and Other Health Problems

How are warts caused?

A wart is a lump on the skin produced when one of the 30 types of papillomavirus invades skin cells and causes them to multiply rapidly. There are several different types of warts: common warts, usually on injury sites; flat warts on hands, accompanied by itching; digitate warts having fingerlike projections; filiform warts on eyelids, armpits, and necks; plantar warts on the soles of the feet; and genital warts, pink cauliflower-like areas that, if occurring in a woman’s cervix, could predispose her to cervical cancer. Each is produced by a specific virus, and most are usually symptomless. Wart viruses are spread by touch or by contact with the skin shed from a wart.


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