Diane Harper watched from the sidelines recently as two Republican presidential contenders got tangled up in the provocative politics of HPV vaccinations.
The University of Missouri-Kansas City Medical School professor and OB/GYN was deeply involved in the patient studies that led to FDA approval of the two HPV vaccines, Gardasil and the less-used Cervarix. After her initial euphoria that there finally was a way to prevent many of the viral infections that cause cervical cancer, she has become an outspoken critic of how the vaccines are being used and marketed.
According to Harper, the issues that stymied Rep. Michele Bachmann of Minnesota — her questionable assertion that the vaccines are unsafe — and Texas Gov. Rick Perry — his mandate to vaccinate schoolgirls — obscure the real concerns.
What troubles Harper are the implicit promises being made for HPV vaccination that it doesn’t live up to.
The vaccines do protect against a group of viruses that are commonly spread by sexual contact. But halting sexually transmitted infections hasn’t been their big selling point, Harper says. Instead, marketing has played up their role in cancer prevention:
“Marketing had a huge impact on the way the public perceives the vaccine. ‘Your daughter can be one less cancer victim.’ Fear is what sells.”
The problem with this approach is that regular Pap tests, which detect precancerous cells, are far more effective than the vaccines at preventing cervical cancer, Harper says. Gardasil may prevent abnormal Pap tests, and it does offer protection from genital warts. But adding vaccine to Pap tests doesn’t improve the odds of avoiding cancer.
“The benefits are nice, but they’re add-on benefits. They’re not critical benefits,” Harper says.
HPV vaccination could lower cancer rates in developing countries where Pap tests are scarce, Harper says. But the profitable markets are in countries like the United States.
Harper hopes vaccinated women here won’t complacently forgo Pap tests. If they do, she says, their cancer risks will rise.
But that’s not the only potential problem Harper sees. Gardasil’s protections have been studied only out to five years. Beyond that time, Harper says, evidence suggests many women begin to lose immunity. When girls are vaccinated at the recommended age of 11 or 12, the shots may start wearing off just as they become most sexually active.
Harper suspects that early age was chosen as much to keep pediatricians’ waiting rooms full as it was to catch girls when they were free of HPV and most likely to benefit from vaccination.
“Parents should have an option. They can say no to their pediatrician at 11,” Harper says. “Maybe (vaccination) can be a going-to-college gift or a getting-a-driver’s-license gift.”
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