Since the initial COVID-19 outbreak, researchers from a variety of scientific disciplines have sought to understand the factors influencing the evolution of cases and fatalities worldwide. This study proposes a two-stage econometric modeling approach that first identifies the speed of transmission followed by an examination of socioeconomic, demographic, health, epidemiological, climate, pollution, and political factors as potential drivers of COVID-19 spread across waves and counties in the United States. Utilizing daily data on confirmed cases and deaths from 3014 counties across 48 contiguous states and the District of Columbia from March 2020 to March 2022, we find that the trajectory of the pandemic and vaccination uptake patterns were influenced by a complex interplay of demographic characteristics, socioeconomic factors, health determinants, and policy interventions that differential affected viral transmissibility, mortality outcomes, and immunization efficacy across the six distinct pandemic waves. This analysis provides insights into pandemic dynamics across distinct waves and geographic regions.
