There are more than 100 types of human papillomavirus (HPV), and most people—about 80 percent of the population—will be infected at some point in their life. In most cases, the virus is virtually harmless and is either cleared from the body or suppressed by the immune system. However, about 30 strains of HPV can cause genital warts and cancers in both men and women.
“Two of the high-risk types, HPV 16 and 18, are responsible for about 70 percent of cervical cancer,” says Dr. Sharon Sung, an obstetrician/gynecologist with Associates in Women's Health Care at St. Luke’s Hospital. “Testing for HPV is usually done in combination with Pap smear screening. How HPV is managed depends on many factors, including a person’s age, her Pap smear results, how long she’s had HPV and what type of HPV she has.”
HPV is generally slow to develop, and most women who are exposed and have an abnormal Pap test result are able to fight off the virus and have subsequently normal Pap tests, Sung says. “If the HPV infection and the abnormal Pap persists--or if the HPV virus leads to a precancerous abnormality--then women may need a minor surgical procedure to remove the part of the cervix affected by the HPV,” she notes.
In recent years, the U.S. Food and Drug Administration approved two vaccines that protect against HPV 16 and 18, Gardasil and Cervarix. (Gardasil also protects against HPV types 6 and 11.) “Each vaccine is given in three separate doses, and both vaccines are more effective when you complete all three doses before you have sex for the first time,” says Dr. Sonali Jain, an obstetrician/gynecologist with Mercy Clinic Women's Health Ladue. “It is recommended that it be given to all girls between the ages of 11 years and 12 years, but it can be given to girls as young as 9 years old. The vaccine also is recommended for all girls and young women aged 13 to 26 years who did not get it when they were younger.” Gardasil also may be given to boys between the ages of 9 and 18 to reduce the chance of getting genital warts, she adds.
“Because these vaccines do not protect against all types of the virus, having received the vaccination does not mean you cannot catch other types of the HPV virus,” Jain says. “Therefore, women who are vaccinated should still have regular cervical cancer screening.”
Last month, the American College of Obstetricians and Gynecologists announced that most women need testing for cervical cancer only every three to five years, rather than annually. For women aged 30 and older, a Pap test should be done, along with an HPV test, every five years. If the HPV test is positive, more frequent testing is needed. And if both the HPV and Pap test are positive, the patient may require further testing and treatment.
“It’s important for men and women to understand how common HPV really is,” Sung says. “This can be very reassuring, since some people are embarrassed at the idea of having a ‘sexually transmitted infection’ and shy away from the subject.”
Jain adds that while regular testing is important, millions of people get HPV. "For most, it does not become cancer. It is important to know that someone with HPV infection can lead a normal, healthy life."