HPV stands for human papillomavirus. You can get HPV by having sex with someone who has the virus. Infection with HPV is common, especially among young people. Half of all sexually active people in the United States will get HPV.¹ But most people never know they have the virus, because it may not cause any symptoms.

There are more than 100 types of human papillomavirus. But only some types of HPV lead to cervical cancer or genital warts.

• Cervical cancer happens when HPV causes abnormal cells in the cervix to grow out of control. HPV can stay in your body for a long time. It can take 10 years or more for a woman to get cancer from an HPV infection. Cervical cancer in the United States is not as common as it used to be. But 10,000 women get it each year, and 3,700 die from the disease.²
• Genital warts (skin growths) may or may not cause symptoms. Even if you treat visible warts, or if the warts go away without treatment, the HPV infection can stay in the body's cells. It's possible to spread genital warts to a sex partner even if you can't see the warts.

The HPV vaccines can help protect people from being infected with some of the most common types of the virus. The HPV vaccines Cervarix and Gardasil protect girls and young women against the two most common types of HPV that cause cervical cancer. Gardasil also protects against the two most common types of HPV that cause genital warts.

The HPV vaccine is a series of three shots given over 6 months. For the vaccine to work best, all three shots must be given. The second shot is given 2 months after the first shot. The last shot is given 4 months after the second shot.

The vaccine doesn't treat an HPV infection. But it may protect a person against types of the HPV virus other than the one causing the infection.

Health insurance may cover all or part of the cost of the vaccine. But if you don't have health insurance, check with your local health department, clinic, or hospital. Girls and boys 18 or younger can get the HPV vaccine for a low cost or even for free through the Vaccines for Children program.

Females may use either Cervarix or Gardasil. Males may use Gardasil.

It is recommended for children age 11 or 12, but can be given as early as age 9. For girls who have not already gotten the vaccine, it is recommended up to age 26. For boys who have not already gotten the shot, the vaccine is recommended up to age 21.

The best time for your child to get the vaccine is before he or she becomes sexually active. This is because the vaccine works best before there is any chance of infection with HPV. When the vaccine is given at this time, it can prevent almost all infection by the types of HPV the vaccine guards against.²

The HPV vaccine can help protect your child from getting the most common types of the virus. This will help prevent him or her from getting genital warts. And it protects women from cervical cancer.

The HPV vaccines were tested in thousands of people before being approved by the U.S. Food and Drug Administration (FDA), and there were no serious side effects. You can't get HPV from the vaccine, and it doesn't contain mercury.

The vaccine series protects against the two or four types of HPV for at least 5 years. Studies are under way to see how long the vaccine will last and if a booster shot is needed. A booster shot is another dose of the vaccine that is given after the first series of shots.

Some people may have mild side effects such as a low-grade fever and soreness in the arm where the shot was given. But neither lasts long. The doctor may have you stay in the office for up to 15 minutes after the shot is given, to watch for any reactions.

Some parents may worry about talking to their young child about the HPV vaccine, because they think it means they have to have the "sex talk." But you don't have to talk to your child about sex if you're not ready. Your child may get other vaccines when he or she is 11 and 12, such as a meningitis shot or a tetanus booster shot. You may want to start the HPV vaccine series when he or she receives these other shots. You can tell your child that these vaccines can help keep him or her healthy and prevent cancer and other illnesses later in life.

If you do decide to talk to your child about HPV and the vaccine, it doesn't mean you're giving your child permission to have sex. It's a chance to teach your child about safe sex and sexually transmitted infections (STIs). This information will be important for when he or she is older and making choices about sex.

Even though the HPV vaccine protects against most cervical cancers, your daughter will need to get regular Pap tests to check for cervical cancer. This is because there are some types of HPV that the vaccine doesn't prevent. Pap tests look for cells that may be, or can lead to, cervical cancer. If these cells are found early and treated, you may prevent cervical cancer.