JACKSONVILLE, Fla. -

As cancer rates overall continue to decline, human papillomavirus-related cancers of the esophagus and anal cancer are on the rise.

At the same time, vaccination rates, which could stem the number of cancer deaths, still remain low.

"You want to protect your child from cancer, and so you should give them the HPV vaccine," said Dr. Joan Macksey, of Memorial Hospital.

For years, doctors have urged young women to be vaccinated against the virus, which is believed to cause cervical cancer, as well as other forms of the disease.

In 2010, only 32 percent of girls ages 13-17 had received the recommended three doses.

Doctors say that changing sexual behaviors -- earlier sex, more partners and especially oral sex -- are contributing to a new epidemic of throat cancer, meaning someone with HPV can get throat or anal cancer if they have HPV.

"It's terrible. Not only is it pre-cancerous or cancerous, but it's very disfiguring," Macksey said.

Two decades ago, about 20 percent of all oral cancers were HPV-related, but today that number is more than 50 percent.

The Food and Drug Administration approved the use of Gardasil for girls in 2006 and for boys for treatment of genital and anal warts in 2009. The vaccine can be given up to the age of 26, though it is most effective when given before any sexual exposure.

"Some of the parents think if I give my daughter the vaccine then she can have sex or she'll think that's the go ahead for sex, but it really isn't," Macksey said.

Gynecologists say it's very important for women to come in for an annual pap smear to detect whether or not they have HPV. Women can also get the Gardasil shot at the gynecologist office.

Doctors say it could prevent 10,000 more cases of oral cancer a year. HPV is the most common sexually transmitted infection. Some strains cause genital warts, but others can result in cancerous cells.

"Your child may not be having sex then, but you don't know who your child will have sex with 10 years down the road," Macksey said.