Boys should get routinely vaccinated against human papillomavirus, a sexually transmitted disease that can lead to cancer, a US government advisory panel recommended on Tuesday.

All boys aged 11-12 should get the HPV vaccine, which is already approved for use in girls, said the recommendations from the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices (ACIP).

The vaccine may offer protection against genital warts and cancers in males, as well as indirectly protect women by reducing the transmission rate of HPV, ACIP said.

The latest recommendations would change the advice for doctors from allowing them to give the vaccine to boys and men up to age 21 to encouraging that it be given as a matter of routine before they start having sex.

Anne Schuchat, director of the CDC's National Center for Immunization and Respiratory Diseases, said the relatively low level of vaccination among girls was a key reason for the change.

"HPV vaccine is not being highly taken up among teen girls," she told reporters, calling the vaccination rate "disappointing."

The committee also agreed that in addition to reducing the burden on women and girls, the HPV vaccine showed great promise in warding off anal cancer and genital warts among boys and men.

"Male vaccination is most effective when coverage of females is low," she said.

HPV is linked to almost 13,000 cases of cervical cancer yearly in US women, 4,300 of which are fatal, and nearly 6,000 cases of anal cancer and 770 deaths in men.

HPV is also suspected to be linked to a rise in head and neck cancers due to its transmission during oral sex.

If the CDC accepts the panel's recommendations, which it is expected to do within the next two months, all insurance companies would be expected to cover the vaccine without any co-pay by the patient.

Merck is the only pharmaceutical company with a quadrivalent vaccine -- one which acts against four separate strains of HPV and is the type recommended by the panel -- licensed for use in boys and girls.

Mark Feinberg, chief public health and science officer for Merck, said the recommendations "mark another important step in helping to protect more people from the HPV-related cancers and disease."

Merck's Gardasil was approved for girls and women from age nine to 26 in June 2006 and for males in the same age range in October 2009. It helps protect against HPV types 6, 11, 16 and 18, that cause the most disease.

GlaxoSmithKline's vaccine, Cervarix, is a bivalent vaccine and was approved in 2009 for females age 10-25.

The HPV vaccine was drawn into a politcal firestorm last month when Republican presidential candidate Michele Bachmann said during a debate that she had heard it could cause mental retardation.

However, no such cases have been documented by US health authorities and Schuchat reiterated that nearly 40 million doses of the three-step HPV vaccine have been distributed in the United States to date and it is considered safe.

The most common side effects are injection site reaction, headache and fever that are mild or moderate in intensity, she said.

HPV is the most common sexually transmitted disease, with more than 40 types, some of which can cause cervical cancer or genital warts. Often, HPV causes no symptoms at all.

At least 50 percent of sexually active men and women will get HPV at some point in their lives, according to the CDC.

The body can usually clear the infection on its own within two years, but certain types, known as oncogenic strains, can turn into cancers and should be closely monitored.

Increasing awareness of HPV's role in other diseases has given a new push to consideration of vaccinating boys and girls, said Kenneth Bromberg, Chairman of Pediatrics and director of the Vaccine Research Center at The Brooklyn Hospital Center.

"In a perfect world, immunization of all girls might be the most cost-effective way of preventing HPV disease in women," he said.

"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."

A separate study released Monday suggested that HPV may also play a role in heart disease among women with no other risk factors, though more research is needed to confirm if that link exists.