Issues of religion and privacy continue to play a role in a health care debate that doctors say is just a matter of science.

Across the country, 19 states now require girls to get the HPV vaccine as a school vaccination prerequisite. Illinois has bills pending that would require the vaccine, as well as fund and educate people about it.

But some groups contest the necessity of the vaccine, which prevents a sexually transmitted infection that can lead to cervical cancer, or challenge it on religious grounds.

Focus on the Family says that abstinence should trump an HPV vaccine.

“Focus on the Family affirms – above any available health intervention – abstinence until marriage and faithfulness after marriage as the best and primary practice in preventing HPV and other STIs,” the group said in a written statement.

Medical professionals don’t agree.

"This is a vaccine that prevents cervical cancer," said Dr. Michelle Luthringshausen, an obstetrics and gynecology specialist at Northwestern's Prentice Women's Hospital. "It's not preventing all sexually transmitted infections. You don't have to tell your 13-year-old daughter it's about sex. It's about cancer."

The genital human papillomavirus is the most common sexually transmitted disease in the U.S., and most infected people don’t know they have it. It causes most cases of cervical cancer and genital warts – affecting approximately 20 million Americans, according to the Centers for Disease Control and Prevention.

The vaccine targets four types of HPV that account for more than 70 percent of cervical cancer cases. The Advisory Committee on Immunization Practices recommends the vaccine – administered in three shots over a six-month period – to girls between the ages of 11 and 12, before they become sexually active.

Northwestern Memorial Hospital hosted “HPV: What’s It Got to Do With Me?” Thursday to teach people about the virus and advocate the need for its vaccine.

“We have done a great job in the U.S. in preventative care for cervical cancer,” said Luthringshausen, the program’s presenter. “There is a lack of cervical screenings worldwide."

The U.S. boasts low incidence and mortality rates because of its preventative care and promotion of the HPV vaccine. According to the American Cancer Society, about 4,070 women died from cervical cancer in 2009. Worldwide, the annual mortality is more than 288,000.

Despite encouraging statistics, some doubt the vaccine’s efficacy. “This vaccine should never have been licensed,” said Nathan Wright, a publisher at Think Choice – an anti-vaccination publishing company. “It is a scam. It has never been proven to save a woman from cervical cancer.”

“It’s a public health issue,” said Luthringshausen. “With the proposed changes in health reform, soon [the vaccine] won’t be a choice."