Evaluation of School Vaccine Coverage and Medical Vaccine Exemptions Following the Repeal of School Entry Nonmedical Vaccine Exemption Options in New York State
Authors: Correira John W. , Kamstra Rhiannon , Zhu Nanqing , Doll Margaret K. 
Published: August 2023

ABSTRACTImportanceFollowing the repeal of nonmedical vaccine exemption options from school entry immunization laws in California, gains in vaccine coverage were partially offset by increases in medical vaccine exemptions. Although several U.S. states, including New York State (NYS), recently adopted similar legislation, the impact of these laws on school vaccine coverage and medical vaccine exemptions has not yet been examined.ObjectiveTo estimate the effects of NYS legislation eliminating nonmedical school entry vaccine exemptions on required vaccine coverage and the uptake of medical vaccine exemptions at NYS schools outside of New York City (NYC).DesignInterrupted time-series analyses using generalized estimating equations to examine longitudinal school immunization compliance data from the 2012-13 through 2021-22 school years.SettingNew York State public and nonpublic schools outside of NYC.ParticipantsSchools that submitted ≥1 compliance report in the time periods before and after the legislative repeal of nonmedical exemptions with publicly available student enrollment data.ExposureNYS Senate Bill 2994A was passed in June 2019, eliminating school entry nonmedical vaccine exemptions; since compliance with the law was evaluated for most students during the following school year, we considered the 2019-20 school year as the law’s effective date.Main Outcomes and MeasuresMain outcomes examined were school required vaccine coverage, defined as the percentage of students at each school who completed all grade-appropriate NYS vaccine requirements, and the percentage of students with a medical vaccine exemption.ResultsAmong 3,525 eligible schools, the implementation of NYS Senate Bill 2994A was associated with an increase in mean required vaccine coverage of 5% and 1% among nonpublic and public schools, respectively, with additional annual increases in coverage observed through the 2021-22 school year. The law’s implementation was also associated with a 0.1% (95% CI: 0.0%, 0.1%) decrease in medical vaccine exemptions at both public and nonpublic schools, and small, but significant mean annual declines in medical vaccine exemptions through the end of the study period.Conclusion and RelevanceThe NYS elimination of school entry nonmedical vaccine exemption options was effective to improve required vaccine coverage; coverage gains were not replaced by increases in medical vaccine exemptions.KEY POINTSQuestionWas the New York State (NYS) law eliminating nonmedical vaccine exemption options from school entry vaccine requirements effective to increase vaccine coverage among NYS schools (outside of New York City)?FindingsUsing interrupted time-series analyses, we found the implementation of the NYS law was associated with an increase in mean required vaccine coverage at NYS schools; small, but significant declines in medical exemptions were also observed in relation to the law.MeaningState legislation eliminating nonmedical vaccine exemption options from school entry vaccine laws can be effective to improve school vaccine coverage without replacement by medical vaccine exemptions.