What is the HPV Vaccine?

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HPV vaccines are given as a series of three shots over 6 months to protect against HPV infection and the health problems that HPV infection can cause. There are three HPV vaccines (Cervarix, Gardasil, and Gardasil 9).  Girls and young women should get any of these HPV vaccines to prevent cervical cancer.

Two of the HPV vaccines (Gardasil and Gardasil 9) also protect against genital warts and anal cancer in both females and males. Boys should get one of these HPV vaccines to prevent anal cancer and genital warts. Girls can get either of these vaccines to prevent cervical cancer, vulvar cancer, vaginal cancer, anal cancer and genital warts.

HPV vaccines offer the best protection to girls and boys who receive all three vaccine doses and have time to develop an immune response before being sexually active with another person. That’s why HPV vaccination is recommended for preteen girls and boys at age 11 or 12 years.

Who else should get the HPV vaccine?

All kids who are 11 or 12 years old should get the three-dose series of HPV vaccine to protect against HPV. Teen boys and girls who did not start or finish the HPV vaccine series when they were younger should get it now. Young women can get HPV vaccine through age 26, and young men can get vaccinated through age 21. The vaccine is also recommended for any man who has sex with men through age 26, and for men with compromised immune systems (including HIV) through age 26, if they did not get HPV vaccine when they were younger.

Human Papillomavirus (HPV) Vaccine

Approximately 79 million Americans are infected with human papillomavirus (HPV), and approximately 14 million people will become newly infected each year. Some HPV types can cause cervical, vaginal, and vulvar cancer among women, penile cancer among men, and anal and some oropharyngeal cancers among both men and women. Other HPV types can cause genital warts among both sexes. Each year in the United States an estimated 26,000 new cancers attributable to HPV occur, 18,000 among females (of which 11,500 are cervical cancer) and 8,000 among males (of which 5,900 are oropharyngeal cancers).

There are, however, two HPV vaccines available (Gardasil® and Cervarix®) which protect against the types of HPV infection that cause most cervical cancers (HPV types 16 and 18). Both vaccines should be given as a three-shot series. Clinical trials and post-licensure monitoring data show that both vaccines are safe.

CDC recommends HPV vaccination Adobe PDF file [PDF – 225 KB] for the prevention of HPV infections responsible for most types of cervical cancer. As with all approved vaccines, CDC and the Food and Drug Administration (FDA) closely monitor the safety of HPV vaccines following licensure. Any problems detected with these vaccines will be reported to health officials, health care providers, and the public. Needed action will be taken to ensure the public’s health and safety.

Read more: HPV vaccination recommendations Adobe PDF file [PDF – 225 KB] , Cervarix® , Gardasil®, Vaccine Information Statements

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How CDC Monitors HPV Vaccine Safety

Vaccines continue to be monitored for safety after they are licensed. Additionally, vaccine safety monitoring is of growing importance due to the development and use of new vaccines, expanded vaccine recommendations, and new global immunization initiatives. Following licensure, CDC and FDA primarily use three systems to monitor and evaluate the safety of vaccines, including HPV. These systems can detect rare adverse events that were not identified during pre-licensure clinical trials. The three systems are:

Vaccine safety surveillance and other vaccine safety activities help ensure that U.S. vaccines are held to very high standards of safety.

A Closer Look at the HPV Vaccine Safety Data

Vaccine Adverse Event Reporting System (VAERS)
In the United States, post-licensure vaccine safety monitoring and evaluation are conducted independently by federal agencies and vaccine manufacturers.  From June 2006-March 2013, approximately 57 million doses of HPV vaccines were distributed  and VAERS received approximately 22,000 adverse event reports occurring in girls and women who received HPV vaccines; 92% were classified as “non-serious.” Reports received by VAERS peaked in 2008 and decreased each year after that; the proportion of female HPV reports classified as “serious” (reports are classified as “serious” if they contain information that the event resulted in hospitalization, prolongation of an existing hospitalization, permanent disability, life-threatening illness, or death) peaked in 2009 at 12.8% and decreased after that to 7.4% in 2013 (for more information, see Morbidity and Mortality Weekly Report (MMWR):
Human Papillomavirus Vaccination Coverage Among Adolescent Girls, 2007-2012 and Postlicensure Vaccine Safety Monitoring, 2006-2013 — United States

Among non-serious adverse events, the most commonly reported generalized symptoms are:

  • syncope (fainting)
  • dizziness
  • nausea
  • headache
  • fever
  • urticaria (hives)

and the most commonly reported local symptoms are:

  • injection-site pain
  • redness
  • swelling

Among the VAERS reports coded as “serious,” headache, nausea, vomiting, fatigue, dizziness, syncope, and generalized weakness are the most frequently reported symptoms.

To date, adverse events reported to VAERS  are consistent with those identified during the vaccine’s pre-licensure clinical trials, and reporting patterns have remained unchanged, with no new concerns, since a summary of VAERS reports was published in 2009.

VAERS data continue to be routinely monitored and analyzed by CDC and FDA, with a detailed review of every serious VAERS report.

Vaccine Safety Datalink (VSD)
In 2011, the VSD studied the occurrence of specific adverse events following more than 600,000 doses of Gardasil.  Adverse events in the HPV vaccinated population were compared to another appropriate population (such as adolescents vaccinated with vaccines other than HPV) and included Guillain–Barré syndrome (GBS), stroke, venous thromboembolism (VTE), appendicitis, seizures, syncope (fainting), allergic reactions, and a potentially life-threatening allergic reaction called anaphylaxis. None of these adverse events were found to be any more common after HPV vaccination than among the comparison groups.

Institute of Medicine
In 2011, the Institute of Medicine (IOM) produced a report, Adverse Effects of Vaccines: Evidence and Causality.  In this report, they concluded that some people who receive injected vaccines, including HPV vaccine, experience syncope.  This report also affirmed that anaphylaxis can occur in susceptible people after they receive of a variety of vaccines, including HPV vaccines.  People with severe allergic reactions to any component of a vaccine should not receive that vaccine.

Post-licensure safety monitoring from June 2006 through March 2013 continues to show:

  • No new or unusual patterns of adverse events to suggest a HPV vaccine safety concern.
  • Syncope (fainting) can occur among adolescents who receive vaccines, including HPV vaccine.  To decrease the risk of falls and other injuries that might follow syncope, CDC’s Advisory Committee on Immunization Practices (ACIP) recommends that clinicians consider observing patients for 15 minutes after vaccination.


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Related Scientific Articles

Klein NP, Hansen J, Chao C et al. Safety of quadrivalent human papillomavirus vaccine administered routinely to females. Arch Pediatr Adolesc Med 2012;166:1140-1148.

Chao C, Klein NP, Velicer CM et al. Surveillance of autoimmune conditions following routine use of quadrivalent human papillomavirus vaccine. J Intern Med 2012;271:193-203.

Gee J, Naleway A, Shui I, Baggs J, Yinc R, Lic R, Kulldorff, M, Lewis E, Fireman B, Daley, MF, Klein NP, Weintraub ES. Monitoring the safety of quadrivalent human papillomavirus vaccine: Findings from the Vaccine Safety Datalink, Vaccine 2011 Oct 26;Vol 29, Issue 46: 8279-8284.

Slade BA, Leidel L, Vellozzi C, Woo EJ, Hua J, Sutherland A, Izurieta HS, Ball R, Miller N, Braun MM, Markowitz LE, Iskander J. Postlicensure safety surveillance for quadrivalent human papillomavirus recombinant vaccine. JAMA 2009 Aug 10;302(7):750-7.

Centers for Disease Control and Prevention (CDC) and ACIP. Quadrivalent human papillomavirus vaccine. [PDF – 444 KB] MMWR 2007 Mar 23; 56(RR-2).

MMWR – FDA Licensure of Bivalent Human Papillomavirus Vaccine (HPV2, Cervarix) for Use in Females and Updated HPV Vaccination Recommendations from ACIP.

MMWR – FDA Licensure of Quadrivalent Human Papillomavirus Vaccine (HPV4, Gardasil) for Use in Males and Guidance from ACIP.