Source: CBSSFBayArea

LOS ANGELES, CA – AUGUST 07: Elias Melgar, 11, from Marina Del Rey Middle School, receives a vaccine against whooping cough at Mark Twain Middle School August 7, 2012 in Los Angeles, California. The boosters, also called Tdap shots, are required of all seventh graders before they can start school. The Los Angeles Unified School District is offering free shots at various clinics in the city to help students make the deadline before school starts on August 14. (Photo by Kevork Djansezian/Getty Images)

OAKLAND (KPIX 5) — Scores of California students may be sent home on their first day of school because of a new vaccine law that took effect this year.

The new state law took effect July 1. Now, parents can no longer use personal or religious beliefs as a reason not to have their kids immunized.

This school year, kindergartners and seventh graders must show proof of immunizations.

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Monday WAS the first day of school for kids in Oakland. Hundreds of them were expected to be sent home.

“There could be a few hundred kids that are not immunized and so we’ll be encouraging them as quickly as possible to get out there,” said Oakland Unified School District John Sasaki. “Their parents may try to drop them off and we’ll have to turn them away.”

Young children who got their personal belief exemptions approved before January 2016, will be grandfathered in. According to the new law, they still must get immunized when they reach seventh grade.