Wart, Flat (HPV)

Warts are growths of the skin and mucous membranes (the mouth or genitals) that are caused by over 100 types of the human papillomavirus (HPV). The virus causes thickening of the top skin layer. Flat warts tend to stay small in size but can be numerous in quantity. They are usually painless and go away on their own, sometimes taking a few months to resolve (but can take up to 2 years).