Anna Giuliano, a cancer researcher at Moffitt Cancer Center in Tampa, Florida, poses a question: "Let's say we have a vaccine to prevent breast or prostate cancer. Do you think we would have any pushback?"
And yet, Giuliano continues, we have a vaccine that prevents an infection that is the leading cause of multiple cancers, and less than 50 percent of the target population gets it.
The human papillomavirus vaccine, commonly known by its commercial names, Gardasil and Cervarix, is best known for protecting against cervical cancer in women. Lesser known is that it also protects against anal, penile and oropharyngeal cancers, the latter of which is one of the fastest growing cancers in the U.S. And the incidence in men is twice that of women.
The HPV vaccine was initially made available for girls in 2006, to protect against the development of cervical cancer later in life. It was only in 2011 that the Centers for Disease Control and Prevention fully recommended the vaccine for both girls and boys between ages 9 and 21. Adolescence is the ideal time for vaccination -- preferably before the onset of sexual activity, since that's how the HPV virus is transmitted.
But because the virus is associated with sex, the uptake of the vaccine has been slower than ideal, says Rodney Willoughby, a member of the American Academy of Pediatrics Committee on Infectious Diseases and a specialist in HPV prevention at Children's Hospital of Wisconsin in Milwaukee.
"It's a sex-associated vaccine," Willoughby says. "That label tainted the vaccine early on. It's a cancer vaccine and should be treated as such."
Need for Bigger Physician Push
About 50 percent of girls in the U.S. are estimated to be vaccinated, says Susan Vadaparampil, a researcher at Moffitt Cancer Center. Vadaparampil and Giuliano recently published a National Institutes of Health-funded study showing that doctors recommended the vaccine to just 15 percent of adolescent boys. In 2011, when the survey was conducted, only 8.3 percent of boys were vaccinated. But by 2012, that had already jumped to 20.8 percent, and by 2012, to 35 percent, Vadaparampil says.
"As a parent, it's very important to advocate for your child," she adds. "It's always OK for parents to bring it up themselves."
At the same time, she recommends having cancer providers come to family medicine physicians to educate them -- and their patients -- about the importance of preventing cancers, even though those diseases aren't likely to strike for decades. "I think there's definitely a kind of time lapse," Vadaparampil says. "People don't see the realness of it."
Another strategy, she says, is to make the HPV vaccine part of a child's routine immunization platform "rather than singling it out." Compliance with the Tdap -- tetanus, diphtheria and pertussis vaccine -- is 80 percent. By not lumping the HPV vaccine in with that, "we're missing clinical opportunities," she adds.
"What is clear is that the main influence on HPV vaccine uptake is the pediatrician/family practitioner," Willoughby says. He adds that the other cancer vaccine -- against hepatitis B, which can cause liver cancer -- is given at birth. "Kids are already little pin cushions, so we wait until they are 11 or 12 [for Tdap and the meningitis vaccine]." That's also the ideal age for the HPV vaccine.
Schools Could Play a Big Role
The real challenge, however, is getting the HPV vaccine endorsed as a requirement for entering school, Giuliano says. "If a vaccine is required for school entry, then you see very high levels of uptake. For those that are not required, it's rare to see uptake beyond 50 percent."
"In my generation we would be lined up in school and vaccinated against measles and polio," she adds. "That message worked."
And in some countries, that message is still working for the HPV vaccine. In 2013, Australia's national health care system adopted a gender neutral HPV vaccine program, purchasing the vaccine for adolescents. As a result, 80 percent of the target male population has been vaccinated, Giuliano says.
In the U.S., programs such as Medicaid and Vaccines for Children have helped cover the cost of the vaccine for underinsured kids. While health disparities normally go the other way -- leaving the less privileged without access to health benefits -- the opposite is true with the HPV vaccine.
"One of the ironies is that coverage is better in the inner city, among non-Caucasians," Willoughby says, adding that minorities are disproportionately more affected by oropharyngeal cancer. "If you are part of this population, and you know your auntie had this, you want to stop it," he adds.
Hispanics also have higher vaccination rates than Caucasians. However, their completion rate (the vaccine is distributed in three doses over a six-month period) is lower than that for whites, Vadaparampil adds.
The population that's largely being missed is the "vaccine hesitancy" group, Willoughby says: more affluent families that may oppose vaccines in principle. Giuliano adds that the hesitancy or outright opposition to the HPV vaccine is an extension of some people's "fundamental distrust of the public health system."
Benefits of the HPV Vaccine
The biological reality is that most sexually active adults will get the HPV virus at some point, and many people will clear it. For others, the virus will morph into cancer many years later. HPV is the leading cause of cervical cancer, and annual Pap smears in women act as a sentinel to full-blown cancer developing by detecting cancer cells early. Men don't have an equivalent test for penile cancer, nor for oropharyngeal cancer, so the HPV vaccine is the best prevention, Vadaparampil says.
Adolescents have been the focus of the vaccine target group because it's better to nip something in the bud before it can begin, so the thought has been to vaccinate kids before they start having sex and can contract (and transmit) the virus. But the vaccine can also be given to adults. "There is some compelling evidence that the vaccine would actually be very useful in an older population," Giuliano says. The Food and Drug Administration set its age limit at 26, but its counterpart in the European Union, the European Medicines Agency, has no such restriction, Giuliano says.
Although most of the trial data is on adolescents and young adults, some trials have shown the efficacy of the vaccine in women up to age 45, specifically in preventing recurrence of the virus, Giuliano adds. "It's an equal opportunity vaccine that affects all of us. Why are we hesitating?"