Flat warts are caused by direct contact with the HPV virus and are highly contagious. The virus that causes warts can be transmitted from person to person, or HPV can be spread from a flat wart on the hand to other parts of the body.

Warts are a skin disease caused by the human papillomavirus (HPV). There are many types of warts and they can appear anywhere on the body. Some warts fall off on their own without treatment, but this can take a long time and can spread.