"Most mothers aren't ready to deal with the possibility of their daughter becoming sexually active, so they tie together the vaccine with more or less an acknowledgement that their daughter is about to become sexually active, whether or not that's true," said Dr. Pichichero.
That's why it's important, he and others said, to emphasize that vaccination is not about sexual readiness, but about preventing cervical cancer. Providing the vaccine has not been shown in any way to increase sexual activity, he and other physicians said. And, Dr. Pichichero added, "studies show, without a doubt, that when you vaccinate at a younger age, you get much higher immunity levels."
Kaiser's Dr. Wibbelsman said he tells parents that at least "10,000 women die each year of cervical cancer and countless others have cervical cancer, and that HPV causes cervical cancer."
Dr. Stan Block, who practices in Bardstown, Ky., with a large adolescent population, said that "numbers give parents something concrete to hang their hats on." He tells many parents that "the lifetime risk of getting cervical, anal, vaginal, or vulvar precancer or cancer goes from about 1 in 20 without vaccination to 1 in 50 with vaccination," and that the risk of venereal warts similarly drops from 1 in 10 without vaccination with Gardasil to about 1 in 100 with vaccination.
"We explain that even precancerous lesions can have serious consequences, like surgery and the inability to have children," said Dr. Block, who estimates that his practice has an 85%-90% HPV vaccination rate in female patients. "You have to test the waters, the comfort level of the child ... but whenever possible, I lay all this out."
When parents refuse the vaccine, he either tells them that he is documenting the refusal in their child's chart or asks them to sign a form to document that they acknowledge the risk of refusing vaccination. "Without a doubt, it's a malpractice risk," he said. Sometimes, he added, such a statement or request results in parents' changing their minds.
• Safety. At least several studies have shown that the vaccine would receive greater acceptance if it was perceived to be safe.
"I tell parents that the vaccine has now been received by literally hundreds of thousands in this country, and that there are no serious adverse events associated with the vaccine," said Dr. Freed. "Then I say that in the same time period, there likely have been at least several thousand young women who have been infected with HPV who will develop precancerous cervical lesions and may go on to develop cervical cancer."
Others said they refer parents to the CDC's Web site for vaccine safety profiles. "This way, it's not me talking, and not the manufacturer, but a body with a lot of credibility," said Dr. Stanley Gall, professor of ob.gyn at the University of Louisville (Ky.) and a member of ACIP's HPV working group.
According to the CDC Web site, approximately 32 million doses of Gardasil were distributed in the United States from the time the vaccine was licensed in 2006 until September 2010. All serious adverse event reports that were made to the Vaccine Adverse Event Reporting System have been fully investigated, with staff finding "no pattern or clustering ... to suggest they were caused by the HPV vaccination," the site says.
Syncope and fainting are common in preteens and teens after injections, the CDC notes, making the recommended 15-minute postvaccination observation period extremely important. Patients should lie down or sit for this period of time.
• Duration of efficacy. Manufacturers have tracked vaccine recipients for up to 8-10 years at this point, with no "breakthrough cases" of HPV infection, sources said.
"We can tell parents that – as with any new vaccine – we can't say how long efficacy will last, but that we do know the vaccine is highly immunogenic, that we're seeing no breakthrough cases in the recipients being followed, and that we know protection will last at least 7.5 years and likely significantly longer," said Dr. Bocchini. If needed in the future, a booster dose will become available.
• Vaccine differences. The most important facts for parents to know, several physicians said, is that both Gardasil and Cervarix protect against the two strains of HPV (types 16 and 18) that are believed to cause 70% of all cervical cancers, and that Gardasil also protects against HPV-6 and -11, the most common cause of genital warts.
Parents and older teens should know the value of protecting against genital warts, they said. "There are about a million new cases of genital warts each year in this country, and the amount of money spent treating them is equivalent to the amount of money spent treating cervical cancer," not to mention the fact that genital warts cause significant anguish, Dr. Gall said.