human papillomavirus (HPV), any of a family of more than 60 viruses that cause various growths, including plantar warts and genital warts, a sexually transmitted disease. Detectable warts can be or removed, usually by chemicals, freezing, or laser, but often recur. Intralesional alpha interferon has been effective in the treatment of genital warts. Genital warts, sometimes called condylomata acuminata, are soft and often occur in clusters. They can occur internally or externally, but even in the absence of warts the virus may be present and transmittable. Problems can result from untreated warts, which can grow quite large, or, in rare cases, from infection of an infant during delivery. In addition, certain strains of HPV are associated with cancer of the cervix, vulva, vagina, penis, and anus, and HPV 16 has been shown to be associated with some forms of Kaposi's sarcoma (see AIDS) and throat cancer. A vaccine approved by the Food and Drug Administration in 2006 can protect a woman against those strains that cause most cases of cervical cancer and genital warts, and a study has shown it may also protect against related throat cancers; HPV vaccination is now recommended for both girls and boys beginning at 11 to 12 years of age.