Introduction to human papillomavirus

Human papillomavirus (HPV) infects epithelial cells, causing warty papules or plaques on the skin. The appearance of warts varies according to the anatomical site and HPV subtype.

Common warts usually occur on the hands, feet and extensor surfaces, and are mainly caused by HPV types 1, 2, 4, 27 and 57. See here for a photo of common warts on the knee. Plantar warts (warts occurring on the bottom of the feet), subungual warts (warts occurring under the nail) and periungual warts (warts occurring around the nail or on the cuticle) are treated as for common warts.

Plane (or flat) warts appear as multiple, small flat lesions on the face and distal limbs. Plane warts are caused by HPV types 3 and 10. See here for a photo of plane warts on the chin.

See also Genital warts (caused by HPV types 6 and 11), and HPV–related oral lesions.