Impact of State Vaccine Mandates on Vaccination Coverage Rates During the COVID-19 Pandemic, September 2021 to September 2022 Open Access

Ballou, Eliza (Fall 2024)

Permanent URL: https://etd.library.emory.edu/concern/etds/1z40kv349?locale=e
Published

Abstract

Background

The Coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 virus, led to widespread illness and prompted an urgent need for public health measures to control its spread. Vaccination emerged as a key strategy for mitigating severe outcomes, including hospitalizations and deaths. In response, states in the United States adopted varied policies to address vaccination uptake. Some states implemented mandates requiring vaccination for specific populations, aiming to increase coverage rates and protect public health. Other states enacted prohibitions against mandates, reflecting diverse political and social contexts that prioritized personal autonomy. A third group of states had no mandates or only one mandate requirement. This study investigates the impact of these state-level COVID-19 vaccination policies on adult vaccination coverage rates from September 2021 to September 2022. The analysis focuses on adults aged 18 and older, excluding mandates related to children, schools, or educational settings, to understand how different policy approaches influenced public health outcomes during the pandemic.

Methods

Vaccination data from the Immunization Information System (IIS), national census estimates for state populations in 2021 and 2022, State and Legislative Control data for 2020 from the National Conference of State Legislature (NCSL), and state vaccine mandate data from the Centers for Disease Control and Prevention (CDC) were used to assess the impact of state vaccine mandates on state-level vaccination coverage rates. The mandate type of each state was used as the exposure and state-level vaccination counts from September 1, 2021, and September 7, 2022, were used as the outcome. Poisson regression was used to estimate the vaccination rate ratios (VRR) and 95% Confidence Intervals (CI) between each type of mandate at the two time periods, assessing the impact of vaccine mandates while controlling for state political power in 2020.

Results

The 50 states and Washington D.C. were analyzed at two time periods, 2021 and 2022. Controlling for state political power in 2020, states with required mandates had higher vaccination coverage rates than states with no mandates (VRR: 2021, 1.10 95% CI 1.01-1.20 and 2022, 1.11 95% CI 1.02-1.22). States with mandate prohibitions had lower vaccination rates than states with no mandates (VRR: 2021, 0.91 95% CI 0.85-0.97 and 2022, 0.92 95% CI 0.86-0.98), and states with mandate requirements (VRR: 2021, 0.82 95% CI 0.75-0.90 and 2022, 0.83 95% CI 0.75-0.91).

Conclusions

This study suggests that during the first and second years of COVID-19 vaccine availability, states with vaccine mandate requirements had a higher rate of vaccination coverage than compared to states with no mandates or states with mandate prohibitions. States with mandate prohibitions had lower vaccination coverage rates than all other states. Further research is needed to assess the impact of the federal vaccine mandate and identify unknown and unmeasured confounders during the same period due to data limitations.

Table of Contents

Chapter I: Introduction ......................................................1

Chapter II: Review of Literature ..........................................6

Chapter III: Methodology ...................................................18

Chapter IV: Results ............................................................25

Chapter V: Conclusions, Plications, and Recommendations ...28

Tables and Figures .............................................................35

Citations ...........................................................................38

About this Master's Thesis

Rights statement
  • Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.
School
Department
Subfield / Discipline
Degree
Submission
Language
  • English
Research Field
Keyword
Committee Chair / Thesis Advisor
Committee Members
Last modified

Primary PDF

Supplemental Files