Abstract
Introduction: Social media increasingly structure public dialogue on vaccination by shaping the visibility, framing, and interpretation of information, as well as the attitudes individuals develop toward immunization.
Methods: We conducted an archival qualitative content analysis of 496 original posts from three private but publicly searchable national Facebook groups during the initial vaccine rollout (December 31, 2020 - January 7, 2021): knowledge-seeking (n=40), pandemic-denial (n=183), and anti-denial/satirical (n=273). Two independent health-psychologist coders applied a predefined scheme (post type, interaction style, emotional tone, thematic content), with discrepancies resolved by a third reviewer (consensus–adjudication approach). Data were summarized descriptively; no personal data were collected.
Results: The analysis revealed substantial differences in communication dynamics. The knowledge-seeking group emphasized inquiry and fact-sharing in a neutral or anxious tone. The anti-denial group employed irony and satire, maintaining a constructive yet emotionally detached communication style. The denial group favored video-based, morally charged, and confrontational discourse, characterized by anger and distrust. Vaccination emerged as the most frequently discussed topic across all groups, though framed in radically different ways. Scientific articles were virtually absent from all communities, even in those oriented toward knowledge.
Conclusion: These findings suggest that online discourse on public health is shaped not only by the content of beliefs but also by emotional tone and rhetorical framing. Understanding these dynamics is essential for designing more effective health communication strategies, particularly in digital environments characterized by polarization and misinformation.