Some girls in Virginia's public schools will need an additional vaccine next fall.

The state will require girls entering the sixth grade to get the Gardisil vaccination that targets two types of Human Papilloma Virus, or HPV. It's a virus that is believed to be responsible for about 70 percent of cervical cancer cases and is spread through sexual activity.

"We believe it's a good vaccine," says Jim Farrell, with the Virginia Department of Health. "And to maximize the benefits of this vaccine, it is best to be given to girls prior to sexual debut."

The vaccine is given in three doses over six months. It typically costs about $375, but officials say that cost would be waived since the state's requiring it.

"Anything that's mandated for school attendance, or daycare attendance, or pre-school attendance in the state of Virginia is provided at no cost to the parents," says Farrell.

According to the Department of Health, parents of fifth grade girls will start receiving information from schools at the end of this school year. Parents will also have the opportunity to opt out for any reason.