Warts are caused by human papillomavirus (HPV). Commonly, these viruses cause squamous epithelial cell proliferation and are found in the upper epidermis. At least 70 types of HPV exist but some types tend to be more common in certain body areas. Warts around fingernails are usually associated with nail-biting or picking and flat warts are seen on the face and back of the hands at times. Filiform (thread-like) and digitate (finger-like) warts are also not uncommon over the face. Genital warts usually occur as a result of the transmission of the virus from contact with a person carrying the virus. Effective treatments that are available for warts include electrocautery or laser ablation.
