Online misinformation is linked to COVID-19 vaccination hesitancy and refusal (Preprint)

BACKGROUND Widespread uptake of vaccines is necessary to achieve herd immunity. However, uptake rates varied across U.S. states during the first six months of the COVID-19 vaccination program. Online misinformation may play an important role in vaccine hesitancy, and there is a need to comprehensively quantify the impact of misinformation on beliefs, behaviors, and health outcomes. OBJECTIVE This work investigates the extent to which COVID-19 vaccination rates and vaccine hesitancy are associated with levels of online misinformation about vaccines across geographical regions. We also look for evidence of directionality from online misinformation to vaccine hesitancy. METHODS Vaccine uptake recordings were taken from Centers for Disease Control and Prevention (CDC) data over the week of March 19 to 25, 2021. Vaccine hesitancy data and misinformation data were taken over the period, Jan 4th to March 25th, 2021. We leverage over 22 M individual responses to surveys administered on Facebook to assess vaccine hesitancy rates, and we identify online misinformation by focusing on low-credibility sources shared on Twitter by over 1.67M users geolocated within U.S. regions. Statistical analysis was done using multivariate regression models adjusting for socioeconomic, demographic and political confounding factors. RESULTS We find a negative relationship between misinformation and vaccination uptake rates. Online misinformation is also correlated with vaccine hesitancy rates taken from survey data. Associations between vaccine outcomes and misinformation remain significant when accounting for political as well as demographic and socioeconomic factors. While vaccine hesitancy is strongly associated with Republican vote share, we observe that the effect of online misinformation on hesitancy is strongest across Democratic rather than Republican counties. Granger causality analysis shows evidence for a directional relationship from online misinformation to vaccine hesitancy. CONCLUSIONS These results indicated that there are geographically located hotspots of vaccine refusal which are associated with online misinformation and unexplained by other factors. Our results support a need for interventions that address online misinformation, allowing individuals to make better-informed health decisions. COVID-19 | Facebook | misinformation | Twitter | vaccine hesitancy | vaccines