What Is HPV and Why Is It a Problem?

Human papillomavirus (HPV) is a virus that can cause different types of cancer (such as cancer of the vagina, cervix, vulva, penis, anus, and throat) as well as genital warts. Research suggests that HPV may be linked to heart disease in women.

People can get HPV from sexual contact (including vaginal, oral, and anal sex) and from some types of skin-to skin-contact. Most people infected with HPV don't know they have it because they don't notice any signs or problems. People do not always get genital warts, but the virus is still in their system and could cause damage. This means that people with HPV can pass the infection to others without knowing it.

The vaccine is an important and effective step in preventing infection and protecting against the spread of HPV.

When Do People Get the HPV Vaccine?

Doctors recommend the vaccine for girls and boys 11–12 years old (though kids as young as 9 also can get it) and for older kids who aren't yet vaccinated.

The vaccine is given as a series of shots:

• Kids and teens ages 9–14 get the HPV vaccine in 2 shots over a 6- to 12-month period.
• Teens and young adults (ages 15–26) get it in 3 shots over a 6-month period. People with weak immune systems also get 3 shots, including those 9–14 years old.

Teens or young adults who didn't start or complete the series of shots can get it up to age 45.

How Does the HPV Vaccine Work?

The HPV vaccine contains a small piece of the virus that teaches the immune system to make antibodies against HPV. It doesn't contain live virus, so it can't cause HPV infection.

It works best when people get all their shots on time. If you're under age 26 and you've missed a shot, you can still catch up. Just ask your doctor about the best way to do that.

The vaccine does not protect people against strains of HPV that might have infected them before getting the vaccine. The most effective way to prevent HPV infection is to get vaccinated before having sex for the first time. But even if you have had sex, it's still the best way to protect against strains of the virus that you may not have come in contact with.

The vaccine doesn't protect against all types of HPV. Anyone having sex should get routine checkups at a doctor's office or health clinic. It's important to get Pap smears when a doctor recommends it — for most girls, that's usually around age 21 unless there are signs of a problem before that.

The HPV vaccine is not a replacement for using condoms to protect against other strains of HPV — and other STDs — when having sex.

What Are the Side Effects of the HPV Vaccine?

Side effects that people get from the HPV vaccine usually are minor. They may include swelling or pain at the injection site, or feeling faint after getting the vaccine. As with other vaccines, there is a rare chance of an allergic reaction.

A few people have reported health problems after getting the shot. The FDA is monitoring the vaccine closely to make sure these are not caused by the vaccine itself.

Most people have no trouble with the vaccine. You can make fainting less likely by sitting down for 15 minutes after each shot.

How Can I Protect Myself From HPV?

The most important way to protect against HPV infection is by getting the HPV vaccine.

For people who have sex, condoms offer some protection against HPV. Condoms can't completely prevent infections because hard-to-see warts can be outside the area covered by a condom, and the virus can infect people even when a partner doesn't have warts. Also, condoms can break.

The only way to be completely sure about preventing HPV infections and other STDs is not to have sex (abstinence). Spermicidal foams, creams, and jellies aren't proven to protect against HPV or genital warts.

If you have questions about the vaccine or are worried about STDs, talk to your doctor.