Human papillomavirus
Human papillomavirus infection (HPV infection) is an infection caused by human papillomavirus (HPV), a DNA virus from the "Papillomaviridae" family. Many HPV infections cause no symptoms and 90% resolve spontaneously within two years. However, in some cases, an HPV infection persists and results in either warts or precancerous lesions. These lesions, depending on the site affected, increase the risk of cancer of the cervix, vulva, vagina, penis, anus, mouth, tonsils, or throat. Nearly all cervical cancer is due to HPV; two strains, HPV16 and HPV18, account for 70% of cases. HPV16 is responsible for almost 90% of HPV-positive oropharyngeal cancers. Between 60% and 90% of the other cancers listed above are also linked to HPV. HPV6 and HPV11 are common causes of genital warts and laryngeal papillomatosis.