In California, parents could claim a personal belief exemption to vaccination, and the rate of kindergartners without up-to-date vaccinations was 9.84% in 2013. In 2016, due to measles outbreaks, California passed a bill banning all personal belief exemptions. The rate was halved to 4.87% in 2017.

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In California, parents could claim a personal belief exemption to vaccination, and the rate of kindergartners without up-to-date vaccinations was 9.84% in 2013. In 2016, due to measles outbreaks, California passed a bill banning all personal belief exemptions. The rate was halved to 4.87% in 2017.