HPV is the most common sexually transmitted infection in the United States. In the United States, an estimated 79 million persons are infected, and an estimated 14 million new HPV infections occur every year among persons age 15 through 59 years. Approximately half of new infections occur among persons age 15 through 24 years and the first HPV infection typically occurs within a few months to years of becoming sexually active.
Ask the Experts: HPV (Human Papillomavirus): Disease Issues
Most HPV infections are asymptomatic and go away completely on their own within 2 years (usually in the first 6 months) after infection without causing clinical disease. Some infections are persistent and can lead to precancerous lesions or cancer. HPV infections caused by certain HPV types cause almost all cases of anogenital warts in women and men and recurrent respiratory papillomatosis.
According to CDC surveillance data from 2015 to 2019, every year in the United States, about 47,199 new cases of cancer (26,177 among women and 21,022 among men) are found in parts of the body where human papillomavirus (HPV) is often found (referred to as HPV-associated cancers). About 79% of these cancers are probably caused by HPV (referred to as HPV-attributable cancers).
Each year, between 2015 and 2019, an average of 12,293 cases of cervical cancer, the most widely known HPV-associated cancer, occurred in the United States. HPV is also associated with vulvar, and vaginal cancer in females, penile cancer in males, and anal and oropharyngeal cancer in both females and males. Between 2015 and 2019, oropharyngeal cancers were the most commonly occurring HPV-associated cancers, with an average of 20,839 reported cases each year (17,238 among men and 3664 among women). See www.cdc.gov/cancer/hpv/statistics/cases.htm and www.cdc.gov/cancer/uscs/about/data-briefs/no31-hpv-assoc-cancers-UnitedStates-2015-2019.htm for more information on trends in HPV-associated cancer.
In the United States, approximately 64% of HPV-related cancers are attributable to HPV 16 or 18, two types included in all HPV vaccines. Approximately 10% are attributable to HPV types 31, 33, 45, 52, and 58, which are included in the 9-valent HPV vaccine.
HPV types 6 or 11 cause 90% of anogenital warts (condylomata) and most cases of recurrent respiratory papillomatosis.
There is no treatment for HPV infection. Only HPV-associated lesions including genital warts, recurrent respiratory papillomatosis, precancers, and cancers are treated. Recommended treatments vary depending on the diagnosis, size, and location of the lesion. Local treatment of lesions might not eradicate all HPV containing cells fully; whether available therapies for HPV-associated lesions reduce infectiousness is unclear.
Occupational infection with HPV is possible. Some HPV-associated conditions (including anogenital and oral warts, anogenital intraepithelial neoplasias, and recurrent respiratory papillomatosis) are treated with laser or electrosurgical procedures that could produce airborne particles. These procedures should be performed in an appropriately ventilated room using standard precautions and local exhaust ventilation. Workers in HPV research laboratories who handle wild-type viruses or “quasi virions” might be at risk of acquiring HPV from occupational exposures. In the laboratory setting, proper infection control should be instituted including, at minimum, biosafety level 2. Whether HPV vaccination would be of benefit in these settings is unclear because no data exist on transmission risk or vaccine efficacy in this situation.
Nonsexual HPV transmission is theoretically possible but has not been definitely demonstrated. This is mainly because HPV can’t be cultured and DNA detection from the environment is difficult and likely prone to false negative results.
- If a person is infected with an HPV strain that does not clear (that is, the person becomes persistently infected) the person cannot be reinfected because they are continuously infected.
- If a person is infected with an HPV strain that clears, some but not all people will have a lower chance of reinfection with the same strain. Data suggest that females are more likely than males to develop immunity after clearance of natural infection.
- Prior infection with an HPV strain does not lessen the chance of infection with a different HPV strain.