An Analysis of Changes in County-Level Travel Behavior Considering COVID-19-Related Travel Restrictions, Immunization Patterns, and Political Leanings

ABSTRACT

The COVID-19 pandemic affected the world in extraordinary ways. Various measures were taken by state and local governments, including the introduction of stay-at-home orders and closures of nonessential businesses, as well as recommendations related to social distancing and the wearing of face coverings. The rollout of testing and vaccination programs were also key actions aimed at limiting the spread of COVID-19. Collectively, these restrictions have resulted in marked changes in travel behavior and patterns throughout the world. In this study, mixed-effects linear regression models are estimated to assess the impacts of COVID-19-related travel restrictions and vaccination rates on daily travel across the United States from January 1, 2020, through August 15, 2021. The results show that daily trips per person were reduced by 15% and 31% in March and April of 2020, respectively, prior to considering the impacts of any government-imposed restrictions. This suggests that government and media coverage of the pandemic played an important role in reducing travel levels. When accounting for the introduction of interventions, ranging from travel advisories to mandatory stay-at-home orders, travel was reduced by an additional 2%-9%. Interestingly, the reductions were less pronounced in areas that strongly supported the Republican candidate in the 2020 presidential election, raising important concerns as to the role of politics and trust in government. Along these same lines, as the duration of mandatory stay-at-home orders increased, travel tended to revert toward prepandemic levels, which may be attributed to quarantine fatigue. Travel levels were also higher among areas with lower median income, as well as those counties that exhibited greater variability in income, illustrating the inequitable impacts of the pandemic on these areas, which tend to include larger proportions of workers in essential industries. The results also show that trip-making increased with vaccination rates, particularly during the early stages of large-scale vaccination programs. Collectively, these insights are important in informing future strategies to mitigate the adverse impacts associated with future outbreaks of new COVID-19 strains and variants. © 2022 American Society of Civil Engineers.