Questions & Answers

Click here for a fully formatted PDF version of these Qs & As.

When did HPV vaccine become available?
On June 8, 2006, the Food and Drug Administration (FDA) licensed the first vaccine developed to prevent cervical cancer and other diseases in females caused by certain types of genital human papillomavirus (HPV). The vaccine, Gardasil (by Merck), protects against four HPV types which are responsible for 70% of cervical cancers and 90% of genital warts.

What kind of vaccine is it?
HPV vaccine is an inactivated (not live) vaccine.

How is this vaccine given?
This vaccine is given as a shot in the muscle.

Who should get this vaccine?
The HPV vaccine is recommended for girls age 11-12 years, but can be administered to girls as young as age 9 years. The vaccine also is recommended for females age 13-26 years who have not yet received or completed the vaccine series.

The vaccine should be given as a series of three injections over a six-month period. The second and third doses should be given two and six months after the first dose. The vaccine can be administered at the same visit as other needed vaccines.

It is best if the vaccine is given before onset of sexual activity. However, females who are sexually active also may benefit from vaccination. Females who have not been infected with any vaccine HPV type would receive the full benefit of vaccination and those who already have been infected with one or more HPV type would still get protection from the vaccine types they have not acquired. Few young women are infected with all four HPV types in the vaccine.

HPV vaccine can be given to females who have an abnormal Pap test or genital warts. However, the vaccine will not have any helpful effect on existing Pap test abnormalities, HPV infection, or genital warts.

Why is the HPV vaccine recommended for such young girls?
This is because the vaccine is most effective in girls/women who have not yet acquired any of the four HPV types covered by the vaccine. Girls/women who have not been infected with any of those four HPV types will get the full benefits of the vaccine.

Why is the HPV vaccine only recommended for girls/women age 9–26 years?
The vaccine has been widely tested in females age 9-to-26 years. Research on the vaccine’s safety and efficacy has only recently begun with older women. The FDA will consider licensing the vaccine for these women when there is research to show that it is safe and effective for them.

What about vaccinating males?
Studies are now being done to find out if the vaccine works to prevent HPV infection and disease in males. When more information is available, this vaccine may be licensed and recommended for them as well. HPV vaccine could protect men directly by preventing penis and anus cancer and also women indirectly, by preventing HPV infection being passed along to them during sexual contact.

Should individuals be screened before getting vaccinated?
No. Girls/women do not need to get an HPV test or Pap test to find out if they should get the vaccine. An HPV test or a Pap test can tell that a woman may have HPV, but these tests cannot tell the specific HPV type(s) that a woman has. Even individuals with one HPV type could get protection from the other vaccine HPV types they have not yet acquired.

How effective is this vaccine?
Four studies, one in the United States and three multinational, were conducted to show how well Gardasil worked in women between ages 16-26 years. A total of 21,000 women were given either the vaccine or a placebo. The results showed that in women who had not already been infected, the vaccine was nearly 100% effective in preventing precancerous cervical lesions, precancerous vaginal and vulvar lesions, and genital warts caused by infection with the HPV types against which the vaccine is directed.

Two studies measured the immune response to the vaccine among younger females age 9-15 years. Their immune response was as good as that found in 16-26 year olds, indicating that the vaccine should have similar effectiveness when used in this younger age group.

How long does vaccine protection last? Will a booster shot be needed?
The length of immunity is usually not known when a vaccine is first introduced. So far, studies have shown women to still be protected after five years. More research is being done to find out how long protection will last, and if a booster dose will eventually be needed.

Who recommends this vaccine?
The Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP) all recommend this vaccine. The vaccine is also recommended by the American Cancer Society.

How safe is this vaccine?
The HPV vaccine has been tested in over 11,000 females (age 9-26 years) in many countries around the world, including the United States. These studies found that the HPV vaccine was safe and caused no serious side effects. A post-licensure safety monitoring plan is in place.

What side effects have been reported with this vaccine?
Mild problems may occur with HPV vaccine, including pain at the injection site (8 people in 10), redness or swelling at injection site (1 person in 4), mild fever (1 person in 10), itching at the injection site (1 person in 30), moderate fever (102°F) (1 person in 65). These symptoms do not last long and go away on their own.

Like all vaccines, HPV vaccine will be monitored for more serious or unusual side effects.

Do women still need to get a Pap test if they’ve been vaccinated against HPV?
Yes! Women should continue to receive regular cervical cancer screening for three reasons. First, the vaccine does not provide protection against all types of HPV that cause cervical cancer. Second, women may not receive the full benefits of the vaccine if they do not complete the vaccine series. Third, women may not receive the full benefits of the vaccine if they receive the vaccine after they have already acquired HPV infection from one of the four types for which the vaccine is preventive.

In addition, vaccinated women should continue to practice protective sexual behaviors since the vaccine will not prevent all cases of genital warts or other sexually transmitted infections.

Does the vaccine protect against all types of HPV?
No, although there are more than 100 types of human papillomaviruses, only four are covered in the vaccine. These four viruses, however, are responsible for 70% of cervical cancers and 90% of genital warts. Because there will be 30% of cervical cancers not prevented by the vaccine, it is important for women to continue getting regular Pap tests.

What if a person doesn’t get all of the recommended three doses?
It is not yet known how much protection girls/women would get from receiving only one or two doses of the vaccine. For this reason, it is very important that individuals get all three doses of the vaccine. If there is a gap in the schedule longer than the recommended time, the series should just be continued from where it left off—there is no need to start the series over.

Who should NOT receive HPV vaccine?
Anyone who has ever had a life-threatening allergic reaction to yeast, any other component of HPV vaccine, or to a previous dose of HPV vaccine, should not get the vaccine.

Pregnant women should not get the vaccine. Although the vaccine appears to be safe for both the mother and developing baby, this issue is still being studied. Inadvertently receiving HPV vaccine during pregnancy is not a reason to consider terminating the pregnancy. Any woman who learns she was pregnant when she got the HPV vaccine is encouraged to call the HPV Vaccine in Pregnancy Registry at (800) 986-8999. Information gathered from this registry will help experts learn how pregnant women respond to the vaccine.

Breast feeding women can safely get the vaccine.

Persons who are moderately or severely ill should wait until their condition improves to be vaccinated.

Will the vaccine be covered by insurance plans?
Most insurance plans and managed care plans cover recommended vaccines for children. However, there may be a lag time after a vaccine is recommended before it is available and covered by health plans.

The Vaccines for Children program provides free vaccines to children and adolescents younger than 19 years of age, who are either Medicaid-eligible, American Indian, or Alaska Native, uninsured, or receiving care in a Federally Qualified Health Clinic or Rural Health Center.

Can the vaccine cause HPV?
No. The vaccine is inactivated so it cannot cause disease-like symptoms or HPV disease.

Questions and answers about HPV disease

Technically reviewed by the Centers for Disease Control and Prevention, May 2007