TUESDAY, Oct. 25 (HealthDay News) -- U.S. health authorities on Tuesday recommended that young males be vaccinated against human papillomavirus (HPV), a sexually transmitted virus that causes most cervical cancers, as well as anal cancer and some cancers of the throat and mouth.

The U.S. Centers for Disease Control and Prevention announced Tuesday morning that its Advisory Committee on Immunization Practices has approved "recommendations for routine vaccination of males 11 or 12 years old with three doses of HPV4 (vaccine)" to shield against the virus.

At this point the recommendation is limited to Gardasil, made by Merck. Another HPV vaccine, GlaxoSmithKline's Cervarix, is not yet included in the advisory.

"The vaccination could begin as young as age 9, and boys and young men 13 to 21 years of age who hadn't received the vaccine should also be vaccinated," Dr. Anne Schuchat, director of the U.S. National Center for Immunization and Respiratory Diseases at the CDC, said in an afternoon press briefing.

The current level of use of the HPV vaccine among girls is "disappointing," Schuchat noted, and since the virus is passed via sexual conduct, "there is the potential that vaccinating boys will reduce the spread of HPV from males to females and reduce some of the HPV burden women suffer from."

An HPV vaccine has been available since 2006, but until now the CDC had only recommended inoculation for females between the ages of 9 and 26 to limit their risk of cervical cancer.

According to Schuchat, the new recommendations were based on the effectiveness of the vaccine in males. She noted that while the numbers of cervical cancers has been decreasing, head and neck cancer and anal cancers -- which affect both genders -- have been on the rise.

One expert agreed with the CDC panel that vaccinating boys should help prevent cancers in both genders.

"In a perfect world, immunization of all girls might be the most cost-effective way of preventing HPV disease in women," said Dr. Kenneth Bromberg, chairman of pediatrics and director of the Vaccine Research Center at The Brooklyn Hospital Center, New York City. "However, since we do not live in a perfect world, a very strong argument can be made for immunizing boys in order to prevent genital warts in males and the prevalence of HPV-related cancers in both boys and girls. The increasing awareness of the role HPV plays in other diseases, such as head and neck cancers and, possibly, heart disease, would be yet another reason to consider universal immunization."

Vaccination against HPV is pricey, with the three-shot series for the Gardasil vaccine typically costing about $390.

The vaccine has been controversial with some parents who contend it could encourage young women and men to engage in sexual relations at an early age.

HPV is widespread among men. An international study published in March in The Lancet found that half of all adult males in the United States may be infected with the virus.

More than 40 strains of HPV exist, and all are passed along by skin-to-skin contact, usually during sexual relations, according to the CDC.

The most well-known strain of HPV causes genital warts. But other strains show no obvious symptoms and clear up on their own with no medical treatment, Dr. Jean Bonhomme, an assistant professor at the Morehouse School of Medicine in Atlanta, told HealthDay.

"Because it normally causes no symptoms, men and women can get it and pass it on without even knowing they have it," Bonhomme said.

Since the virus spreads through skin contact, normal protections that prevent the spread of disease through body fluids won't work, Bonhomme said.

"Diseases like herpes and HPV cannot be completely prevented by condoms because they are both spread by contact with skin," Bonhomme said. "If the virus comes into contact with the scrotum or thighs, you can still be infected."

Men don't have the screening tools for HPV-related cancers that are available to women. A Pap test can detect cervical cancer in women, Bonhomme said, but there's no comparable test for penile or anal cancer in men. As a result, many men don't realize they have these cancers until they begin showing late-stage symptoms.

The U.S. Food and Drug Administration approved the HPV vaccine Gardasil for use in women in 2006. Three years later, the FDA approved a second HPV vaccine, Cervarix. Vaccination is recommended for 11- and 12-year-old girls and for young women ages 13 through 26 who have not yet been vaccinated.

"The idea is to vaccinate before they become sexually active," said Debbie Saslow, director of breast and gynecologic cancer programs for the American Cancer Society. "Afterward, it's much less effective."

Saslow and Bonhomme, who is also president of the National Black Men's Health Network, said that beyond the direct health risks, there are other compelling reasons to extend HPV vaccinations to males.

For one thing, it would be simpler to vaccinate everyone than to have separate guidelines for boys and girls, Saslow said. There's also an argument for gender equity, in that only women are being vaccinated for a disease that affects both sexes, she added.

Another strong argument in favor of male HPV vaccination, Bonhomme said, is that by only immunizing half the population, health officials are not attacking the problem with full force.

"Where are women getting the virus from?" he asked. "If you don't vaccinate the guys, then you aren't helping the women."

HPV has been shown to increase a man's chances of contracting penile and anal cancer, particularly for gay males. Men who have sex with men are about 17 times more likely to develop anal cancer than straight men, according to the CDC.

About 1 percent of sexually active men in the United States have genital warts at any particular time, according to the CDC. Annually, about 800 U.S. men contract HPV-related penile cancer and about 1,100 men get HPV-related anal cancer.

"These are relatively rare cancers," said Saslow. "However, for men who have sex with other men, their risk is significantly higher than the general population."

Researchers at the University of Texas Medical Branch at Galveston reported Monday that HPV may increase a woman's chances for heart disease, even if she doesn't have any recognized cardiovascular risk factors.

More information

The U.S. National Institutes of Health has more on HPV.