Give me your best shot! Diffusion of complete versus booster COVID-19 vaccines across US counties

This research compares drivers of full COVID-19 vaccinations and booster doses across US counties. Booster doses are contingent upon primary doses being received, and the risk attitudes and propensities to get vaccinated may respond to different motivations across individuals, along with distinctions in the supply chain. Our results, obtained in a quantitative framework through fractional probit, logit and quantile regressions, show that new COVID cases do not significantly impact vaccinations, while supply chain aspects via doctors’ visits have a positive impact. Income, race, age, and education also play a significant role. Further, political ideologies matter, while government decentralization does not. The differences in the effects across primary versus booster doses are discussed.