Photo: Getty Images; Illustration by Bloomberg View
Photo: Getty Images; Illustration by Bloomberg View

Michael Douglas may have done more for awareness about human papillomavirus than all the education programs health advocates have ever sponsored. The actor revealed this week that his throat cancer was caused by an HPV infection, the result of his having oral sex with an HPV-infected woman.

The HPV problem can certainly use the attention. A dozen or so variants of HPV, the most common sexually transmitted disease, cause cancer. For people who don’t have the virus, vaccines can prevent infection. Yet, the inoculations are underused.

Two vaccines -- Gardasil and Cervarix -- have proved effective against cervical cancer, while Gardasil is known to also protect against anal, vulvar and vaginal cancers. The shots (a series of three) may also prevent cancer of the penis and the oropharynx, the middle part of the throat. Those cancers should decline in any case, to the extent the vaccines make HPV infection less prevalent.

The trouble is, just 35 percent of U.S. teenage girls get all three doses, data from 2011 suggest, though the Centers for Disease Control and Prevention has recommended the vaccinations since 2006. The figure was just 1 percent for boys; the vaccines were available but not recommended for them until 2012.

Slow Introduction

New vaccines often take time to catch on, but HPV is an especially worrying case. A study published online in March in Pediatrics examined two vaccines for adolescents that have been introduced since 2005 -- a tetanus booster and a meningitis inoculation -- as well as the HPV vaccine. The percentage of female teenagers who got the tetanus and meningitis shots was substantially higher than the share who received the HPV inoculation. By 2010, the tetanus shot had reached 81 percent and meningitis, 63 percent.

If anything, the HPV vaccine may be losing ground. In a 2010 government survey, the percentage of parents who said they didn’t intend to have their female adolescents inoculated increased to 44 percent, from 40 percent in 2008.

This trend corresponds with a significant rise in unwarranted concerns about side effects. In the 2008 survey, 4 percent of parents gave safety as their main reason for not vaccinating a child against HPV; in 2010, 16 percent did. And this was before Republican presidential candidate Michele Bachmann said in a 2011 debate that the vaccine can cause mental retardation.

In fact, no serious safety issues have arisen in pre-licensing studies for the HPV vaccines, involving tens of thousands of volunteers, or in the administration of more than 46 million doses of the vaccines since they were approved. Caught up in the politics around adolescent sexuality -- some conservatives fear inoculation against a sexually transmitted disease will spur promiscuity -- the HPV vaccine has been stuck with a bad rap. It’s the responsibility of pediatricians, who administer HPV shots, to dispel the myths and ensure that parents get accurate information.

By drawing attention to the links between sex, HPV infection and cancer, Douglas’s revelation may chip away at the biggest reason parents give for failing to vaccinate their teens: that it isn’t necessary.

Yet another large impediment remains: the inability of many parents to grasp that their children will eventually become sexually active. In the 2010 survey, 11 percent of the parents who refused the vaccine for their daughter did so because she wasn’t sexually active, yet the shots are most useful before sexual debut. After infection, a vaccine does no good, and in the absence of inoculation, more than half of sexually active people become infected with HPV at some point.

States’ Role

To help parents see HPV vaccination as the norm, every state should include HPV on the list of infectious diseases for which children must be inoculated in order to enroll in school. So far, only Virginia and the District of Columbia have done so. It’s true that HPV isn’t spread as easily as chickenpox or whooping cough. But it is communicable.

In addition to medical exclusions, 48 states allow religious exemptions and 20 permit philosophical ones, so parents utterly opposed to the vaccine could still find a way out. The majority, we expect, would come to see the vaccine for what it is: a remarkable advance that will allow future generations to lead healthier lives, something no parent should deny a child.

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