How many kids are vaccinated at your child's school? Federal health officials think you should be able to easily find out.

Last school year, only 21 states posted for individual schools, , counties or areas of the state. The Centers for Disease Control and Prevention has been quietly prodding more states to make the information available online.

CDC officials made the push more public during a press conference Thursday. They said parents could use the information to weigh their child's risk vaccine-preventable illnesses at specific schools or school districts. And it could help health officials identify pockets of unvaccinated children.

Nationally, vaccination rates for both toddlers and kindergartners appear to be high and steady in recent years, at above 90 percent.

More information: CDC report: www.cdc.gov/mmwr