New research strongly suggests that the HPV vaccine works.

The prevalence of dangerous strains of the human papillomavirus — the most common sexually transmitted infection in the United States and a principal cause of cervical cancer — has dropped by half among teenage girls in the past decade, a striking measure of success for a vaccine that was introduced only in 2006, federal health officials said.

“These are striking results,” Thomas R. Frieden, director of the federal Centers for Disease Control and Prevention, told The New York Times. “They should be a wake-up call that we need to increase vaccination rates. The bottom line is this: It is possible to protect the next generation from cancer, and we need to do it.”

But unless these numbers change a significant number of minds, many parents won’t.

The HPV vaccine is not a popular one in the United States. More than 40 percent of parents say their children are not up to date on the HPV vaccine (three doses are recommended over a six-month period for boys and girls aged 11-12), and that they do not intend to seek out the vaccine for their sons and daughters. Many cite safety concerns. Some parents also felt that the shot wasn’t necessary for teens who weren’t sexually active (in fact, it’s only effective before HPV is contracted, so teens who aren’t yet sexually active are in the best place to benefit from the vaccine).

Particularly given the success of the vaccine, those numbers are disheartening, and the number of young women who may die unnecessarily from a preventable illness is bleak. Dr. Frieden of the CDC says that 50,000 girls alive today will eventually develop fatal cervical cancer. Today, those girls are an abstraction. In 40 years, they will be our daughters and daughters-in-law. Our sons, too, are at risk — the human papillomavirus prevented by the HPV vaccine series causes 70 percent of all throat cancers.

Will such “striking” results lead parents to embrace what Dr. Frieden called an “anti-cancer vaccine?” The CDC suggests that the time has come to “ramp up our efforts” to promote the vaccination, but it’s unclear to me as a parent that researchers have truly grasped the complexities of the parental resistance to HPV vaccination.

“We thought perhaps many parents would think the HPV vaccine would give kids permission to have sex, and therefore not allow their children to get it. But that wasn’t it,” Dr. Paul Darden, lead author of the National Immunization Survey of Teens (which led to the statistics cited above), and professor of pediatrics at the University of Oklahoma College of Medicine, told CNN. “They seemed to be skeptical of its safety, which is odd, because it’s shown to be effective with few side effects. We have a vaccine that protects against cancer. Why not vaccinate your child? I don’t get it.”

As I’ve written before, I do get it. The only one of my children who is at the age for HPV vaccination is, in fact, fully vaccinated — but it wasn’t an easy process. A child may receive the first of his three shots at an annual physical, but the remaining two require additional pediatrician visits for an otherwise healthy preteen.

That same child is likely to question the reason for the shots, and although there’s really no need to get too detailed (most children will see preventing something called “papillomavirus” as no less valid than preventing “polio”), parents who are uncomfortable talking about sex may find these shots difficult to explain to a curious son or daughter.

There are, in other words, other significant barriers to full HPV vaccination. The fact that more girls and boys get a first dose of the vaccine than complete the series supports the idea that those barriers are more important than physicians and researchers may realize. “Safety concerns” sound better than “convenience,” but convenience may have more impact than we’re willing to admit.

What might increase parental acceptance of the HPV vaccination? An education campaign, perhaps. But it may take more — development of a vaccine suited for annual physicals, better support for parents educating teens, convenient clinics or a willingness to administer the shot outside regular working hours, for example — to get parents over hurdles that we haven’t even admitted stand in our way.

THE PEW RESEARCH CENTER, always a font of interesting factoids, conducted a nationally representative survey of 1,197 lesbian, gay, bisexual and transgender adults and found, among other things, that the median age at which respondents said they first felt they “might be something other than heterosexual or straight” was 12.

Sitting in a “move-up ceremony” with several dozen sixth-, seventh- and eighth-graders recently, I couldn’t help but think about that particular statistic.

The sixth-graders, one of whom was my child, were mostly without gender characteristics, other than those they had created themselves with their blue blazers or wobbly high heels. They were similar in height, mostly prepubescent and still plump with childhood. Many of those who had foresworn skirts or particularly long or short hair could easily have been of either sex.

But the graduating eighth-graders — what a different picture. Boys a foot taller than their tallest sixth-grade counterparts, with a little stubble. The girls, too, were changed, and not just by the makeup most wore.

It’s a big few years that lie ahead for my oldest child and his classmates. I knew these years would include more sexual thoughts, dreams and worries. I knew, too, on some level, that this was the time when sexual identity came to the forefront for many pre-teenagers. I just hadn’t really thought hard about what that meant.

If a child, at 12 or thereabouts, begins to sense that he or she may not drop neatly into the sexual norms, what are the odds that that child will share those feelings with a parent?

Probably not very high. Of the respondents to the Pew survey, “just 56 percent say they have told their mother about their sexual orientation or gender identity, and 39 percent have told their father.” Those numbers encompass all generations, but they still support a suspicion that talking to a parent about one’s emerging sexual self isn’t high on a teenager’s list.

Which means it’s up to parents to convey, in as many ways as we can, that however that identity shapes is fine with us.

Contact KJ Dell’Antonia at:

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