Will Parents Still Turn Down an 'Anti-Cancer Vaccine?' 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 last decade, a striking measure of success for a vaccine that was introduced only in 2006, federal health officials said on Wednesday. "These are striking results," Thomas R. Frieden, director of the Centers for Disease Control and Prevention, told The Times's Sabrina Tavernise. 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 C.D.C. 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 C.D.C. 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 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? As I've written before, I do get it. The only one of my children who is of an 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 we haven't even admitted stand in our way.