There are several different subtypes of warts, which are associated with infection with different variants of HPV.[1] Wart subtypes are generally classified based on appearance and the the area of the body affected.[2]
Common warts can appear anywhere on the body, but are often found on the hands.[2]
Genital warts are typically sexually transmitted and can appear on the genitals or in the space between the thighs. They can also form inside the vagina or anal canal. Although it has been estimated that 10-20% of the population may have genital HPV infections, only an estimated 1% develop genital warts.[3]
Plantar warts appear on the soles of feet, and are often painful, affecting walking or running. Plantar warts also tend to shed the HPV virus, which can spread to other regions of the skin or contaminate surfaces, potentially infecting other people.[4]
Mucosal papillomas are warts that appear on mucous membranes. They are white in appearance, and commonly affect the mouth, the vagina, or the conjunctival mucosa (the thin mucous membrane lining the inside of the eyelids).[5]
Subungual and periungual warts form under (subungual) or around (periungual) fingernails and toenails.
Flat warts are small (1-7 mm) fleshy growths that may be present in multiple numbers (up to hundreds). They tend to appear around the face and forehead. Flat warts are common in children but rare in adults.[1]