Impact of governmental regulations on compliance with MMR immunizations in Northern California

California's Senate Bill 277 (SB277) was mandated to reduce the prevalence of measles by eliminating personal belief exemptions. This study evaluated seven county-level records to determine the impact of SB277 on immunizations among kindergarteners in Northern California.

This study used a quantitative postintervention secondary data analysis.

This study included three kindergarten schools in seven Northern California counties during three academic years from 2015 to 2019.

Sixty-three previously collected school measurements involving 4,626 students were included in a secondary analysis. The study used grouped logistic regression to evaluate the variations in immunization compliance records (2015-16 vs. 2017-18 and 2018-19) among kindergartners in seven counties.

This study found no significant differences in (1) overall county-level measures and (2) the likelihood that kindergartners would be current with measles-mumps-rubella (MMR; OR = 1.12, CI = 0.79-1.62) or be up-to-date with five immunizations (OR = 1.08, CI = 0.77-1.52) post-SB277 versus pre-SB277.

This study showed that SB277 had a small clinical but nonstatistically significant impact on kindergartners' up-to-date with up-to-date rates of compliance with five immunizations and those current with two doses of MMR in seven Northern California counties. Despite the passing of SB277, vaccine-hesitant parents have continued to seek alternatives to immunizations.