Vaccine Misinformation and Social Determinants of Vaccine Intentions in a Pandemic

Objective: This study explores the indirect effects of misinformation on vaccine intentions via social norm perceptions. Methods: A causal mediation analysis with 332 participants was conducted, examining the direct and indirect effects of misinformation on vaccine intentions through social norms. Participants reported beliefs and intentions in response to a hypothetical pandemic scenario involving a fictitious virus, COVID-66. Results: Misinformation significantly reduces vaccine intentions. Post misinformation exposure changes in first-order normative beliefs mediated about 40% of the total effect on vaccine intentions. When pre-post changes in both first and second-order beliefs were considered, the mediation effect increased to 43.93%. Specifically, changes in beliefs about neighbours mediated 56.91% of the misinformation effect, followed by friends (56.24%), work colleagues (52.66%), and city population (50.62%). Conclusion: Social norm perceptions play a critical role in the impact of misinformation on vaccine intentions. Public health interventions should combine misinformation correction with efforts to shape positive social norms, particularly within close social groups, to enhance vaccine uptake. Keywords: