California’s new, more stringent law on childhood vaccinations, SB 277, doesn’t fully kick in until July 1. But it started protecting the public months ago when parents heard from schools and doctors that they would no longer be able to claim a “personal belief exemption” from immunizations if they wanted to enroll their children.

The proof is in the numbers. The percentage of fully vaccinated kindergartners entering the state’s schools in 2015-2016 was the highest in a decade: 92.9%, up from 90.4% last year. State health officials say the measles outbreak at Disneyland a year ago might have scared a few parents off the vaccination fence, but SB 277, combined with another bill from 2012 that required parents to talk to a pediatrician before obtaining an exemption, had more to do with it.

It’s a relief to see an immediate boost in immunization rates after the nasty political battle last year. Legislators faced fierce opposition from a small group of people who believe that vaccinations can harm children and even cause autism. Scientific studies don’t support this belief, yet California unwisely granted immunization waivers based on these unfounded fears. The result was a dangerous decrease in vaccination rates in both rural and affluent communities, including Santa Monica and Marin County.

The vaccination rebound validates the suspicion that the falling rates were caused in part by procrastination, not politics. Schools encouraged an increase in partially immunized students by allowing parents to sign a form promising they would finish the vaccinations, but the promise wasn’t well enforced. This year, the percentage of such enrollees dropped by the same amount the overall immunization rate increased.


Next fall vaccination rates should increase yet again as the holdouts decide to home-school their children or comply with the new law. This is important because, while the overall rates are promising, there are still too many California counties that fall short of reaching so-called herd immunity level, which ranges between 90% and 95% of children vaccinated. Los Angeles County just barely hits that level.

The immunization rate won’t reach 100% because some children have legitimate medical reasons for avoiding vaccination — and are especially endangered when their classmates aren’t immunized. It took guts for legislators to pass this law in the face of vitriolic attacks by anti-vaccination forces. But as the numbers already show, it was worth it.

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