PATHOGENS

• The most common viral sexually transmitted infection.
• All anogenital warts are caused by human papillomavirus (HPV) infection.
• Most (>90%) anogenital warts are benign, caused by HPV subtypes 6 and 11, which are "low-risk" (for malignancy) HPV subtypes.
  • HPV subtypes 16 and 18, the most common "high-risk" subtypes, cause ~70% of cervical cancers but usually do not cause warts.
  • These other "intermediate risk" HPV subtypes, including 16, 18, 31, 33, and 35, are associated with high-grade squamous intraepithelial neoplasia (HG-SIL) and are occasionally found in warts, particularly in persons with concurrent HIV infection.
• For additional non-genital wart information, see the HPV module.