NEW YORK --Virginia Governor Tim Kaine plans to sign legislation mandating use of Merck & Co.'s Gardasil cervical cancer vaccine for school-age girls.

Kaine said he want to mandate the shot for girls entering sixth grade in 2009, according to spokesman Kevin Hall. Kaine's statements came during a public appearance in Norfolk, Va., Thursday, Hall said yesterday.

Virginia would be the second state to require the vaccine. Last month, Texas Governor Rick Perry said he was mandating school-age vaccination.

Gardasil won US approval in 2006 as the first vaccine to prevent the sexually transmitted human papilloma virus, or HPV, which causes cervical cancer.

The vaccine is Merck's most important new product, capable of generating as much as $3 billion a year, analysts have said. Fourth-quarter Gardasil sales reached $155 million.

About 7.5 million US women have the virus that causes cervical cancer, 63 percent more than previously thought, according to projections issued this week by the National Cancer Institute.

In the United States, where Pap smear screening to detect cervical cancer is widespread, about 11,000 women are expected to be diagnosed with cervical cancer this year and 3,670 will die from it, according to the National Institutes of Health.

Merck said last month it was ending its lobbying campaign among the states to make the vaccine mandatory after state officials and physician groups complained there wasn't enough funding or public acceptance to require the vaccine.

Groups such as the Family Research Council and Focus on the Family oppose making the shot mandatory, saying parents should make the decision. Other groups have questioned the need for making the vaccine mandatory because HPV isn't spread by casual contact, as measles and polio are.

© Copyright 2007 Globe Newspaper Company.