Legislative and administrative actions by the state of California were associated with a decrease in the rate of kindergartners entering school without up-to-date vaccinations. This observational study by S. Cassandra Pingali, MPH, MS, of Emory University and coauthors, focused on three statewide initiatives: a 2014 bill requiring parents to prove they had discussed the risks of not vaccinating their children with a healthcare provider before getting a personal belief exemption; a 2015 educational campaign by state and local health departments to educate school staff on conditional admission criteria that allow students more time to catch up on vaccinations; and a 2016 bill banning all personal belief exemptions for vaccinations.
Researchers used school entry data to calculate rates of kindergartners attending California schools without up-to-date vaccines. The authors report the rate of kindergartners without up-to-date vaccinations decreased from 9.84% during 2013 (before the three statewide interventions) to 4.87% in 2017 (after the interventions). Limitations of the study include a limited time period for examining each intervention and students with varying vaccination status not specific to particular vaccines.