Any parent who refuses to vaccinate their child in California will be breaking the law as of January 2016. There are no exceptions.

Governor Jerry Brown signed the legislation on Tuesday, making California the strictest State in America – and it means that all children must be vaccinated before they can attend school.

Sfgate.com reports:

Noting the “widespread interest and controversy” surrounding SB277, Brown said he signed the bill because “the science is clear that vaccines dramatically protect children against a number of infectious and dangerous diseases.”

SB277 eliminates an exemption many parents have used to opt their children out of some of all of the 10 required school vaccines, based on personal or religious beliefs. The new law takes effect on Jan. 1. But even after that date, children enrolled in school or day care who are unvaccinated because of a personal belief exemption can continue to attend until their next scheduled vaccine check. Such checks occur in kindergarten, seventh grade or when students enter a new school.

“While it’s true that no medical intervention is without risk, the evidence shows that immunization powerfully benefits and protects the community,” Brown wrote in a signing message with the bill.

Noting the “considerable debate” in the Legislature about the vaccine mandate, Brown called attention to an amendment allowing children to receive a medical exemption from a doctor. That exemption is broad and can be based on family medical history—such as a sibling’s adverse reaction to a vaccine. Many of the thousands of parents who lined Capitol hallways to express their opposition to the bill had said medical exemptions were too difficult to obtain.

“SB277, while requiring that school children be vaccinated, explicitly provides an exception when a physician believes that circumstances—in the judgement and sound discretion of the physician—so warrant,” Brown wrote.