Social Proof as a Vaccine Booster: Enhancing the Efficacy of Fact-Based Corrections of Online Vaccine Misinformation during Pandemics

In the battleground of pandemic information, vaccine misinformation spreads with virus-like efficiency across social media, potentially undermining public health efforts when they're most crucial. While platforms deploy algorithmic corrections as digital antibodies against false claims, these interventions often fail to penetrate the protective barriers of deeply held skepticism. This study examines a novel immunization strategy: fortifying factual corrections with social proof. Through a controlled experiment simulating a novel pandemic scenario ("COVID-66"), we measured how vaccine intentions fluctuated when exposed to misinformation followed by different corrective treatments. Our findings reveal a compelling asymmetry: while algorithmic corrections alone successfully bolstered overall vaccine intentions compared to untreated controls, they failed to sway the unvaccinated and partially vaccinated—the very groups most critical to achieving population immunity. However, when corrections were combined with normative messaging showing peer acceptance of vaccines, these resistant groups showed significant positive shifts in vaccination intent. Further dissection through mediation analysis unveiled the mechanism behind this enhanced efficacy: unlike standalone corrections that worked through multiple pathways, the combined approach primarily operated by reshaping perceptions of social consensus, which subsequently realigned personal intentions. These results suggest a powerful prescription for pandemic communication: facts alone may not persuade the hesitant, but facts embedded within a supportive social context can overcome resistance where traditional approaches fail. By bridging the gap between cognitive correction and social influence, this research offers practical tools for crafting public health messages that resonate even with those most resistant to conventional expertise.