Human Papilloma Virus (HPV) Vaccine

Gardasil® is the newly recommended Human Papilloma Virus (HPV) vaccine. The Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention recommends Gardasil for girls and women 9-26 years of age. The majority of sexually active individuals have been infected with HPV at some point in their lives, and most are not aware of the infection. In many cases, the immune system is able to clear the infection within 1-2 years. However, certain strains of HPV may linger on the cervix for many years, and persistence of the virus is considered a risk factor for the development of cervical cancer.

In the United States, approximately 4,000 women die from cervical cancer each year; worldwide deaths from cervical cancer number approximately 270,000 (i.e., rates are higher in areas where Pap smear screening and early treatment are not readily available). Gardasil protects against HPV Types 16 and 18, which are responsible for about 70% of all cervical cancer and most vaginal and vulvar cancers. It also protects against HPV Types 6 and 11, which cause about 90% of genital warts. Gardasil is a promising step toward significantly reducing HPV related infection and disease.

Gardasil Overview:


  • There are approximately 40 different HPV types associated with vulvar, vaginal or cervical infection and disease. Gardasil protects against 4 important HPV types.
  • Gardasil does not protect against the HPV types responsible for 30% of cervical cancer.
  • Girls/women who have not yet been exposed to HPV will benefit most from the vaccine.
    Vaccine trials: In the unexposed group, the vaccine was 98.8% effective in preventing significant HPV related disease and 93.4% effective in preventing genital warts. In the general population, which included girls/women already exposed to one or more of viruses covered by Gardasil, the vaccine was approximately 40% effective in preventing significant cervical disease and 68.5% effective in reducing genital warts. Girls/women who may have been infected with one or more of the viruses covered by Gardasil will develop immunity against the HPV types they have not yet acquired. It is rare that an individual will be infected with all four of the viruses covered by Gardasil.

Pap Smears

  • The Pap smear remains a very important screening test for cervical cancer detection and early treatment. Women who receive Gardasil should continue to have regular Pap smears. Remember that 30% of cancer-causing HPV strains are not covered by the vaccine. Also, women who do not receive all three doses of the vaccine, or who were not vaccinated on the correct schedule, will not receive the vaccine's full benefits.
  • As with any vaccine, the vaccine may not result in protection in all vaccine recipients.


  • Gardasil is given in a series of 3 injections, over a 6 month period. Maximum protection is obtained one month after the third dose.
  • The length of vaccine protection (immunity) is unknown; so far, vaccinated persons are protected for five years. Research is ongoing to determine the length of immunity and if a booster dose will be needed.
  • It is not yet known how much protection would be obtained after receiving only one or 2 doses of the vaccine. For this reason, it is very important that girls/women get all 3 doses as recommended.

HPV testing prior to immunization

  • HPV testing is presently FDA approved for use with a Pap smear result of "Atypical Squamous Cells of Undetermined Significance" (ASCUS) and as an adjunct to Pap smears in women over 30.
  • HPV testing prior to immunization is not necessary or recommended.


  • Gardasil has been tested in over 11,000 females in many countries around the world; these studies have shown no serious side effects. Of patients who have side effects, 90% noted soreness at the injection site and 50% noted headaches.
  • The vaccine is not recommended in pregnancy.

Consistent condom use is an important component in the prevention of HPV and other sexually transmitted infections. A recent study demonstrated a 70% reduction in HPV infection among participants who used condoms consistently.

The 3-dose vaccine will be available through the Tang Center at the Allergy, Travel and Immunization clinic. To make an appointment, call (510) 643-7177. For the current price, please call the Tang Center cashier at 642-8448.

Additional information on the HPV vaccine is available at Centers for Disease Control or the California Department of Health Services.

Disclaimer: The information provided here is not intended to diagnose, treat or provide a second opinion on any health problem or disease. It is meant to support, not replace, the relationship that exists between an individual and his/her clinician.

Last revised: August, 2006

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