This paper explores how public health authorities' vaccine communication strategies during the COVID-19 pandemic interacted with pre-existing levels of institutional trust, and how these trust levels shaped perceived opportunities and constraints for communicating trustworthiness in high- and low-trust national environments.
The study employs an exploratory qualitative comparative case study design, analysing vaccine communication strategies in Norway and Romania. These cases were selected due to their contrasting levels of public trust and vaccine uptake. The analysis draws primarily on semi-structured elite interviews with national-level public health communicators, complemented by selected communication artefacts and documentary sources.
The exploratory comparison suggests that Norway's high level of institutional trust enabled a communication strategy based on transparency and voluntary participation, contributing to high vaccine uptake. In contrast, Romania's low-trust context led authorities to rely on intensive expert visibility, depoliticised sources, narrative campaigns, community and role-model involvement, and constant engagement. Political instability, fragmented medical trust, and the politicisation of sources further constrained authorities' ability to build trustworthiness, contributing to lower vaccine uptake. Across both cases, pre-existing trust levels shaped which dimensions of trustworthiness were most salient and which communication strategies were seen as feasible or risky, rather than determining outcomes in a simple causal way.
The study is limited to two country cases and seven elite interviews, which constrain generalizability. The analysis focuses on communicators' perspectives, not on public attitudes or behavioural outcomes, and does not seek to establish causal relationships between specific communication strategies and vaccination uptake. Instead, it uses interview accounts and contextual data to explore how public health authorities understood, articulated, and operationalised trustworthiness in different trust environments, thereby offering analytically rich insights and ideas for future cross-national and mixed methods research.
Public health authorities should design vaccine communication strategies that are sensitive to existing trust levels and maintain consistency over time. Strategies effective in high-trust contexts may be ineffective or counterproductive in low-trust settings.
The paper contributes to the literature by exploratively linking vaccine communication strategies to pre-existing societal trust levels and discussing how shifts in communication can exacerbate or mitigate trust deficits in public health crises.
