Childhood vaccination rates decling nationwide

To go to premier charter school in St. Louis, students have to be up todate on their vaccines and go. >> School nurse Virginia Wilson makes sure they are.>> So, it's a big chunk of your job in the beginning of the school year. >> It is my entire job at the beginning of the school year. >> And she says it's getting harder.>> How many kindergarteners this year needed vaccines. >> We probably at for our school around like 20% need them. NBC News medical unit and researchers at Stanford University crunched scho ...