The California Senate approved a bill today that could end parents' ability to forgo mandatory vaccines for their kids based on personal-beliefs, reports the Los Angeles Times. If the bill is approved by the Assembly and signed by Governor Jerry Brown, then a lot more kids will have to be vaccinated against infectious diseases like the measles.

More than 13,500 kindergartners in the state have obtained waivers based on their parents' personal beliefs (the belief that vaccines are unsafe, for instance). If the bill becomes law, children will have to be vaccinated before they start attending kindergarten. But unvaccinated children who are already in school because of a personal-belief waiver won't be required to get shots until they reach the seventh grade or until they move to a different school district. The only exemption that will remain is one based on medical problems — problems that include a weak immune system — which will have to be checked out by a verified physician.

The vote was 25-10; most Republicans voted against. Mandatory vaccines are a controversial issue, especially given the recent Disneyland measles outbreak that resulted in more than 130 cases in the state. "Vaccines are one of our greatest medical advancements," Senator Richard Pan, a pediatrician who coauthored the bill, told the Los Angeles Times. "And to protect the health of our students and our greater community, this bill is urgently needed to boost vaccination rates."