Separating fact from fiction: Understanding the HPV vaccine

ANN ARBOR, MI – Many parents are still divided over a new vaccine that can provide protection against human papillomavirus, or HPV, a very common sexually transmitted disease that is linked to cervical cancer and genital warts.

Some parents caution that the vaccine, called Gardasil, will encourage sexual activity. Others wonder how effective the new vaccine is, and if it can protect against all types of HPV. There are many parents, too, who see the vaccine as an opportunity to reduce their child’s risk for cervical cancer.

But sorting through all of the information about HPV, cervical cancer and the HPV vaccine – and deciding what’s right for your child – can be a tedious process, says Amanda F. Dempsey, M.D., Ph.D., MPH, a pediatrician at the University of Michigan C.S. Mott Children’s Hospital.

To help separate HPV fact from fiction, Dempsey, a member of the Child Health Evaluation and Research (CHEAR) Unit in the U-M Division of General Pediatrics, offers parents these five facts about HPV and the HPV vaccine.

5 facts about the HPV vaccine

The vaccine can prevent a very common infection that is not completely controlled by condoms. According to the Centers for Disease Control and Prevention, more than 80 percent of adults by age 50 will be exposed to HPV. Unlike other sexually transmitted diseases that are mostly transmitted by blood or other body fluids, HPV is primarily passed on by skin to skin contact. “That’s why condoms are not 100 percent effective in preventing the spread of HPV,” says Dempsey. “HPV is a virus that lives on the skin, and a condom may not cover all areas of the skin where HPV could be found.”

The vaccine is nearly 100 percent effective. Clinical studies have shown that Gardasil – approved by the FDA for females ages 9 to 26, and recommended by the CDC for girls ages 11 to 12 – is nearly 100 percent effective in providing protection against the four HPV strains it covers. “The four types of HPV covered in the vaccine are responsible for the highest percentage of disease related to HPV,” notes Dempsey. “The vaccine covers types 6 and 11, which are thought to be responsible for more than 95 percent of genital warts cases, and types 16 and 18, which are believed to be responsible for more than 70 percent of cervical cancer cases.”
Gardasil only protects against four types of HPV. There are more than a hundred types of HPV, and it is important to remember that Gardasil only protects against four strains, cautions Dempsey. “Even though the vaccine is 100 percent effective at providing protection against these four types of HPV, it does not protect against all types of HPV or all forms of cervical cancer.”

The vaccine will not encourage sexual activity. “Many people have raised the issue of the HPV vaccine being viewed as a license to have frequent or earlier sex,” says Dempsey. “Scientific evidence, however, does not support the idea that a person’s behavior can be influenced by a vaccine for a sexually transmitted disease.” She says that much like using a seat belt doesn’t promote reckless driving, preventing cancer through a vaccine is not expected to change a person’s sexual behavior.

The incidence of HPV and cervical cancer could be greatly reduced. “Several studies based on mathematical models suggest that during the next several decades the HPV vaccine could reduce the incidence of cervical cancer by 70 percent or more,” says Dempsey.
She also notes that parents’ resistance to the use of the vaccines could, in fact, become a major barrier to the use of this preventive treatment, if their concerns and questions about the HPV vaccines are not adequately addressed.

Dempsey also recently led a study to gauge parents’ acceptance of the new HPV vaccine for their preadolescent children. The study, published in the journal Pediatrics, found that parental beliefs about the benefits of HPV vaccinations, the opinions of peers and doctors, and their personal experiences with STDs or HPV-related illnesses were actually more influential on their decision-making process than general education materials alone. Results from this study also reveal parents to be more enthusiastic about vaccinating female than male children.

Additionally, a recent poll conducted by the C.S. Mott Children’s Hospital National Poll on Children’s Health asked U.S. parents if they would support a school mandate for the HPV vaccine. The report found that the majority of U.S. parents are not in favor of HPV vaccine mandates, with only 44 percent in support of a school mandate.