HPV vaccine now recommended for boys. Would you have your son get the shot?

It's official: Doctors with the Centers for Disease Control and Prevention now recommend that 11- and 12-year-old boys also get the controversial HPV vaccine Gardasil, which is supposed to protect against cervical cancer.

HPV, or Human Papilloma Virus, is a group of viruses spread by skin-to-skin and sexual contact. While there are more than 100 strains of HPV out there, only about 15 of them cause genital warts and cancers of the vagina, vulva, anus, penis, and throat as well as cervical cancer. Vaccinating boys before they become sexually active should prevent them from passing HPV along to their future sex partners.

But parents have balked at the idea of vaccinating young kids against a sexually transmitted disease, and medically unconfirmed reports of adverse reactions to Gardasil haven't helped the cause. According to Anne Schuchat of the CDC's National Center for Immunization and Respiratory Diseases, only 44 percent of girls have received one HPV vaccine, and just 27 percent of girls have had all three of the doses needed to fully protect against cervical cancer. Though Gardasil was tested and approved for use in males, only 1.5 perecnt of boys are being vaccinated against HPV; the hope is that the CDC's new recommendation will boost those numbers, Schuchat told USA Today.

Though HPV is most commonly linked to cervical cancer in women-4,000 women in the U.S. die from it each year-a study published earlier this year in the medical journal "The Lancet" shows that as many as 50 percent of men are probably infected with some form of the virus, Reuters reported in March.

The vaccine has been controversial from almost the moment that the CDC first recommended the three-shot series to girls and women age 9 to 26, and encouraged parents to vaccinate their 11- and 12-year-old daughters. Their reasoning? If girls are vaccinated before they become sexually active, then by the time they're actually at risk for developing cervical cancer they'll already be protected by it. The vaccine does not protect people who have already been exposed to HPV.

But not all medical professionals are on board with that idea. Almost all HPV infections are naturally cleared by the immune system, several experts have pointed out, and routine pap smears usually catch precancerous cells early enough for successful treatment. Cervical cancer develops so slowly that the American College of Obstetricians and Gynecologists now recommends that women be screened for it every three years instead of annually. And since the vaccine just came on the market five years ago, no one knows how well it really protects against infections contracted decades down the road. "The relationship between infection at a young age and development of cancer 20 to 40 years later is not known," wrote Dr. Charlotte Haug in a 2009 editorial in "The Journal of the American Medical Association." "The true effect of the vaccine can be determined only through clinical trials and long-term follow-up."

Two years after Gardasil was recommended by the CDC, the lead developer of the vaccine warned that more research is needed. "The rate of serious adverse events [with Gardasil] is greater than the incidence rate of cervical cancer," Dr. Diane Harper, director of the Gynecologic Cancer Prevention Research Group at the University of Missouri, said at a vaccine conference in 2009. (For the record, the CDC disagrees. "We don't believe there is any evidence to suggest any severe, life-threatening outcomes with this vaccine," Schuchat says).

Parents, what do you think: Would you have your son get the shot?

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