Provisional Entrants, Exemptions, and Kindergarteners Up-to-Date on Vaccination Before and After a Regulatory Change in Pennsylvania, 2015-2019

Objectives: Before the 2017-2018 school year, Pennsylvania shortened the grace period for provisional entrants—kindergarteners who are not up-to-date on vaccination and do not have medical or nonmedical exemption—from 8 months to 5 days. We analyzed the impact of this change on school-entry vaccination status. Methods: Using data from the Pennsylvania Department of Health for school years 2015-2016 through 2018-2019, we examined state-level trends in Pennsylvania kindergarteners’ vaccination status, including the percentage who were up-to-date on each required vaccine, provisionally enrolled, medically exempted from vaccination, and nonmedically exempted from vaccination. Using the Spearman correlation coefficient, we assessed associations at the school level among changes in kindergarteners’ vaccination status after the grace period was shortened. Results: From 2016-2017 to 2017-2018, the provisional entrance rate of kindergarteners in Pennsylvania decreased substantially after the change in the grace period (from 8.1% to 2.2%), the medical exemption rate remained stable, and the nonmedical exemption rate increased slightly (from 1.8% to 2.5%). The percentage of kindergarteners up-to-date on required vaccines increased or remained stable across the study period except for polio, which decreased from 97.9% in 2015-2016 to 96.2% in 2018-2019. The change in provisional entrance rate was negatively associated with change in kindergarteners up-to-date on required vaccines (ρ range, −0.30 to −0.70) but not with change in medical or nonmedical exemptions (ρ range, −0.01 to −0.08). Conclusions: Efforts to reduce provisional entrants may increase the percentage of kindergarteners up-to-date on vaccinations at school entry without a corresponding increase in exemptions.