HPV Vaccine: Frequently Asked Questions
Kathryn S. Brigham, MD
What is HPV?
HPV stands for Human Papillomavirus. There are more than 100 different strains, or types, of this virus. Some strains cause warts on hands and feet, some strains cause genital warts, and other strains can cause cancer, including cancers of the cervix, vagina, vulva, anus, mouth, and throat.
How is HPV spread?
It is spread through skin-to-skin contact. Genital HPV is the most common sexually transmitted infection in the United States. It has been estimated that 75 to 80% of sexually active adults will have a genital HPV infection by the age of 50.
What do the HPV vaccines protect against?
There are currently two HPV vaccines available in the United States: Gardasil® and Cervarix®. Gardasil protects against the HPV strains 6, 11, 16 and 18. HPV strains 6 and 11 cause about 90% of all genital warts, while HPV strains 16 and 18 cause about 70% of all cervical cancers. Cervarix only protects against the HPV strains 16 and 18. Both vaccine series involve three shots spread out over six months.
How common is cervical cancer?
Worldwide, cervical cancer is the third-most-common type of cancer in women. It is less common in the U.S., due to the use of Pap tests to screen for the early signs of cervical cancer. However, 12,000 women in the U.S. still get cervical cancer each year, and in 2007, more than 4,000 women in the U.S. died from cervical cancer.
Do the vaccines protect against any other cancers?
Yes. Gardasil has also been shown to protect against cancers of the vulva, vagina and anus.
Should my daughter be vaccinated against HPV?
Both the and recommend that girls routinely receive this vaccine at ages 11-12 years. While this may seem like a young age to vaccinate against a virus spread through sexual contact, it is crucial that this vaccine be given before the onset of sexual activity, in order to prevent young women from acquiring this potentially cancer-causing virus. The vaccines do not treat HPV-related diseases after HPV has been acquired. The vaccine should not be given to people who have a history of a severe allergic reaction to components of the vaccine.
Should my son be vaccinated against HPV?
The Centers for Disease Control and Prevention Advisory Committee on Immunization Practices recently recommended that Gardasil should be given routinely to boys ages 11-12 years. In addition, it recommended that Gardasil should be given to males 13-21 years who have not yet received this vaccine. This vaccine will prevent genital warts and anal cancer in males, as well as prevent transmission of cervical cancer-causing strains to female partners. As with young women, it is important to give this vaccine before the onset of sexual activity. Cervarix is not recommended for males.
Are the HPV vaccines safe?
The vaccines have been given to millions of people worldwide. As of June, 2011, more than 35 million doses of the HPV vaccine had been distributed in the U.S. Studies have shown no serious safety concerns and both vaccines are very safe.
Do the vaccines contain thimerosal or mercury?
No, there is no thimerosal or mercury in either vaccine.
What are the most common side effects of the vaccines?
The most common side effects include pain where the shot was given, fever, dizziness and nausea. In addition, some adolescents have fainted after receiving the vaccination, so the adolescent should consider sitting down for 15 minutes after receiving the vaccine. It does not cause or any serious neurological conditions.
Will women who have been vaccinated still need to have Pap tests?
Yes. While these vaccines protect against strains of HPV that cause 70% of cervical cancers, there are still other strains of HPV not included in the vaccine that cause the remaining 30% of cervical cancers. For this reason, women still need to have Pap tests starting at age 21.
Learn more about the Division of Adolescent and Young Adult Medicine.