Efforts to mitigate the impact of COVID-19 now focus primarily on encouraging vaccination. These efforts have been hampered, however, by vaccine hesitancy. A better understanding of the factors associated with vaccination may help identify those most likely to experience hesitancy and inform the content of public health outreach efforts. The aims of this study were to evaluate whether two theory-based factors (perceived vaccine efficacy and vaccination intention) and political party affiliation were associated with vaccination in the United States (US) and to provide descriptive analysis of factors shaping vaccination decisions. A longitudinal online survey was conducted with 108 adults in the US. Participants completed surveys in July 2020 (Time 1) and October 2021 (Time 2). As hypothesized, greater vaccination intention and perceived vaccine efficacy were significant predictors of vaccine uptake. The second hypothesis was also supported as political party affiliation was associated with vaccination (i.e. Democrats were more likely to vaccinate than Republicans). Descriptive data indicated that vaccinated participants (including those reluctant to vaccinate at Time 1) had been motivated by a desire to protect themselves and others from COVID-19. Participants who had chosen not to vaccinate were influenced by a variety of factors including concerns about vaccine safety and efficacy. Understanding the predictors of vaccination is critical to identifying those unlikely to vaccinate and creating effective interventions to encourage the uptake of this essential public health strategy. Messaging should emphasize the efficacy of COVID-19 vaccines and be delivered by those seen as trustworthy in communities prone to vaccine hesitancy.
Keywords: COVID-19; perceived efficacy; political party; vaccination.