What Is Human Papillomavirus?

Human papillomaviruses (HPV) are a group of more than 100 viruses. Certain types of HPV can cause genital warts, which are growths or bumps that appear:

  • On the vulva
  • In or around the vagina or anus
  • On the cervix
  • On the penis, scrotum, groin, or thigh

Some strains of HPV are associated with cervical cancer, or less commonly, cancers of the vulva, anus, or penis.

HPV is easily spread during oral, genital, or anal sex with an infected partner. About two-thirds of people who have sexual contact with a partner who has genital warts will develop them also. Usually this happens within three months of contact.

Symptoms include:

  • Fleshy, raised growths with a cauliflower shape in or around the vagina or anus; on the cervix; and on the penis, scrotum, groin, or thigh
  • Bleeding
  • Itching
  • Irritation
  • Burning
  • Secondary bacterial infection with redness, tenderness, or pus

Most people will be exposed to a form of HPV at some point in their lives. Not all will become infected or develop symptoms. Warts can appear within several weeks after sexual contact with an infected person, or they can take months to appear.

Risk factors for contracting HPV include:

  • Age: 15-30 years old
  • Multiple sexual partners
  • Having sex without condoms
  • Skin-to-skin contact with an infected partner
  • Previous history of genital warts
  • Pregnancy
  • Smoking
  • Oral contraceptives
  • Having sex at an early age

Treatment for genital warts may include:

  • Topical treatments
  • Cryosurgery (freezing)
  • Electrocautery (burning)
  • Laser to destroy the warts
  • Surgical removal for large warts
  • Anti-viral drug (called alpha-interferon) injected directly into warts that keep recurring

What Is the HPV Vaccine?

The HPV vaccine consists of noninfectious virus-like particles. These particles produce antibodies to prevent HPV from infecting cells. The vaccine is given by injection into the muscle.

The vaccine Gardasil protects against four types of HPV. Two of the HPV types are the main types that cause cervical cancer and the other two are causes of genital warts.

Another vaccine, called Cervarix, protects against the two main HPV types that cause cervical cancer.

Who Should Get Vaccinated and When?

The Centers for Disease Control and Prevention (CDC) recommends vaccination for girls 11-12 years old. The vaccine can be given to girls as young as 9 years old. The CDC indicates that it is important for girls to get the HPV vaccine before their first sexual contact. The vaccine is most effective for these girls. For girls and women aged 13-26 who did not receive the HPV vaccine when they were younger, "catch-up" vaccinations are recommended. Males aged 9-26 years old may be vaccinated to reduce the risk of genital warts.

Gardasil is approved for use in females and males aged 9-26 years old. Cervarix is approved for use in females aged 10-25.

Gardasil is given as a three-dose series. The first dose is given at any time, with a second dose two months after the first, and the third six months after the first. Additional doses are not recommended. Cervarix is also given in three doses. After the first dose is given, the following doses are then given one and six months later.

What Are the Risks Associated With the HPV Vaccine?

Research suggests that the vaccine does not appear to cause any serious side effects. Like any vaccine, though, it has the potential to cause serious problems, such as a severe allergic reaction.

Some problems have been associated with the HPV vaccines, like pain, redness, swelling, or itching at the injection site. Other side effects include:

  • Gardasil
    • Headache
    • Mild to moderate fever
  • Cervarix
    • Fatigue
    • Headache
    • Muscle pain
    • Joint pain
    • Gastrointestinal symptoms

Who Should Not Get Vaccinated?

Do not get the vaccine if you:

  • Had a life-threatening allergic reaction to yeast or any other component of the vaccine
  • Are a pregnant woman (the effects are still being studied)
  • Are moderately or severely ill (wait until you have recovered)

What Other Ways Can HPV Be Prevented Besides Vaccination?

Avoiding physical contact with an infected sexual partner is the only way to completely prevent the spread of an HPV infection. Latex condoms may help reduce the spread of HPV infection and genital warts. However, condoms are not 100% effective because they cannot cover the entire genital area.

Other preventive measures include:

What Happens in the Event of an Outbreak?

According to the CDC, approximately 6.2 million new cases of sexually transmitted HPV infections are reported each year. Twenty million people in the US are already infected. Since HPV vaccines cannot treat infections that already exist, the best way to prevent further spread of the disease is to get the vaccine before becoming infected.