This article examines how the rejection of established scientific knowledge on vaccination by public policy actors in Slovakia contributed to broader societal, public health, and economic consequences during and after the COVID-19 pandemic. The analysis is situated at the intersection of scholarship on vaccine hesitancy, science denial, populist communication, and the mainstreaming of extremist narratives. Within this framework, science denial is understood as a political and discursive process through which empirically validated claims concerning vaccine safety, effectiveness, and risk–benefit balance are contested and delegitimized in the public sphere.

Methodologically, this study employs a qualitative case study of Slovakia based on the systematic analysis of publicly available and verifiable sources, including the international academic literature on vaccine hesitancy, Slovak survey-based research on public attitudes and institutional trust, epidemiological evidence, official policy documents, and analyses of the economic costs associated with low vaccination uptake. This multi-source approach enables the examination of linkages between political communication, institutional distrust, and vaccination-related outcomes.

The findings suggest that vaccine hesitancy in Slovakia is shaped less by educational attainment than by political distrust, low institutional confidence, and susceptibility to conspiratorial narratives. A key mechanism identified is the mainstreaming of antivaccine discourse, whereby narratives initially associated with extremist and conspiracy-oriented actors gradually gained legitimacy within broader populist politics and, at times, informed policy signals. These dynamics contributed to the erosion of trust in scientific and public institutions, intensified social polarization, adverse health outcomes linked to persistently low vaccine uptake, and rising economic burdens.

Theoretically, this study contributes to the existing literature by conceptualizing vaccine hesitancy as a politically mediated and institutionally reinforced process. Practically, it underscores the importance of evidence-based health governance, stronger political accountability, and coordinated state-level strategies to counter health misinformation and rebuild public trust.