If there were a vaccine that could prevent cancer, would lawmakers recommend it?

Maybe not, according to research on the human papillomavirus (HPV) vaccine released today in JAMA, the Journal of the American Medical Association.

Princeton researchers Jason L. Schwartz and Laurel A. Easterling found that, eight years after the Centers for Disease Control and Prevention (CDC) first recommended routine HPV vaccination, there are only two jurisdictions that require the immunization.

They are the state of Virginia and Washington, D.C. Rhode Island has passed HPV regulations that will take effect in August.

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Vaccination Requirements Are Somewhat Common

State requirements for vaccinations are not uncommon and are usually quick to follow CDC recommendations.

Hepatitis B is similar to HPV in that it is a virus predominately spread by sexual activity. Eight years after the CDC recommended the hepatitis B vaccine, it was required by 36 states and D.C.

The varicella vaccine, which prevents chicken pox, was required by 38 states and D.C., eight years out.

“These differences contradict the recent, coordinated message by vaccination advocates that HPV vaccines ought not to be treated differently than any other routine vaccine,” Schwartz said in an email to Healthline.

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HPV Vaccine Prevents Cervical Cancer

The HPV vaccine is best known for its role in preventing cervical cancer. Almost all cervical cancers are caused by HPV.

The vaccine was originally recommended only for girls. But recent research has found that the HPV virus causes many other types of cancer as well.

HPV is attributable to more than 90 percent of anal cancers, 75 percent of vaginal cancers, 72 percent of cancers of the throat and neck, 69 percent of vulvar cancers, and 63 percent of cancers of the penis. Some strains of HPV also cause genital warts.

The that all boys and girls aged 11 or 12 receive the three-dose series of the quadrivalent HPV vaccine, which protects against the four types of HPV that cause most genital warts and cancers.

While the reality of exactly what the HPV virus can do to one’s nether regions may not be polite dinner conversation, there’s not much debate surrounding the utility of the vaccine.

“In addition to the large clinical trials showing the safety and effectiveness of both HPV vaccines prior to their approval by the FDA, the vaccines have now been used in over 100 countries for nine years,” Schwartz said. “In the U.S., nearly 70 million doses of HPV vaccines have been distributed without any evidence of serious safety concerns.”

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Vaccination Rate Much Higher in Europe

In Europe, where the precautionary principle drives much public health decision-making, standards on vaccination are often viewed as less profit-driven than those in the United States.

European medical authorities recently announced an investigation into two rare, non-fatal side effects of the vaccine. However, there are no plans to alter recommendations.

European HPV vaccine uptake rates have far outpaced those of the United States. The rate of HPV vaccination in the United Kingdom, for example, is 90 percent.

So, why is the U.S. rate lingering at 38 percent for girls and 14 percent for boys?

“School requirements are a mainstay of U.S. vaccination policy, widely used by states to promote high vaccination rates,” the JAMA article reads. “Attention to their potential value has been largely absent from recent discussions of strategies to improve HPV vaccination rates.”

Politics vs. Science

There’s no easy answer to the question of why HPV vaccination hasn’t caught on in the United States, but a 2007 article by Schwartz published in Clinical Pharmacology & Therapeuticsgives at least some insight into the political climate present when the vaccine was first introduced.

Despite being lauded by the medical community as a cancer prevention tool, the HPV vaccine was essentially thrust into a political cauldron with “an unlikely alliance of civil libertarians and social conservatives, whose opposition to government interference with parental decision-making trumped their general support for the vaccine, and self-described ‘vaccine safety’ groups that are vocal critics of most U.S. vaccine policies,” Schwartz wrote.

The pot boiled over when a state requirement in Texas was resoundingly viewed as a move by then-Governor Rick Perry to grant a favor to pharmaceutical giant Merck.

Although the science surrounding the vaccine is solid, there’s no telling when or how public health educators and healthcare providers will earn the public’s trust.

“The principal challenge for advocates of the vaccine has been effectively framing it as a safe, effective vaccine against a cancer-causing virus,” Schwartz said.

Perhaps the recent approval of Gardasil-9, , will thrust the vaccine back into the spotlight and allow proponents another chance to sing the praises of a product that prevents six kinds of cancer.