The COVID-19 pandemic requires rapid public compliance with advice from health authorities. Here, we ask who was most likely to do so during the first wave of the pandemic. We conducted cross-sectional and panel surveys in eight Western democracies between March 19 and May 16 asking 26,508 citizens about their protective behavior relating to COVID-19. Consistent with prior research on epidemics, we find that perceptions of threat and risk factors are crucial and culturally uniform determinants of protective behavior. On this basis, authorities could potentially foster further compliance by appealing to fear of COVID-19, but there may be normative and practical limits to such a strategy. Instead, we find that another major source of compliance are feelings of efficacy. Using individual-level panel data, we find evidence that feelings of efficacy are amendable to change and exert a causal effect on protective behavior. Importantly, the effects of such feelings are especially strong among those who do not feel threatened, creating a path to compliance without fear. In contrast, two other major candidates for facilitating compliance from the social sciences, interpersonal trust and institutional evaluations, have surprisingly little motivational power. To combat future waves of the pandemic, health authorities should thus focus on facilitating efficacy in the public.

The management of the COVID-19 pandemic critically hinges on the approval of safe and effective vaccines but, equally importantly, on high willingness among lay people to use vaccines when approved. To facilitate vaccination willingness via effective health communication, it is key to understand both levels of skepticism towards an approved COVID-19 vaccine and the demographic, psychological and political sources of this skepticism. To this end, we examine the levels and predictors of willingness to use an approved COVID-19 vaccine in large, representative surveys from eight Western democracies that differ both politically and in terms of the severity of the pandemic: Denmark, France, Germany, Hungary, Sweden, Italy, United Kingdom, and United States (total N = 9,889). The data reveal large variation in vaccination willingness, both across and within countries ranging from 79 % in Denmark to 38 % in Hungary. Thus, most national levels fall below current best estimates for the required threshold for reaching herd immunity. Across national and demographic groups, the analyses demonstrate that a lack of vaccination willingness is associated with low levels of trust in authorities, conspiracy-related beliefs and a lack of concern about COVID-19. These factors also account for cross-national levels in vaccine willingness.

Health authorities emphasize the importance of "radical transparency" in communicating about future COVID-19 vaccines to counter conspiracy-based skepticism. While this resonates with research that highlights uncertainty as a major psychological predictor of conspiracy-related beliefs, no systematic evidence exists regarding the effectiveness of transparency as communication strategy. This study tests the effects of transparent communication about a COVID-19 vaccine using a pre-registered experiment fielded to large, representative samples of Americans and Danes (N > 6,800). The evidence confirms that positive but vague vaccine communication does not increase vaccine support but rather infuses attitudes with conspiracy-related beliefs. Against the hopes of authorities, however, there is little evidence that transparency alone can reduce vaccine skepticism, unless this transparency discloses a highly safe and effective vaccine. Additional analyses suggest that this reflects that vaccine skepticism is not grounded in psychological uncertainty but in deep distrust of authorities, which impedes the effectiveness of their communication.

"Fake news" are widely acknowledged as an important challenge for Western democracies. Yet, surprisingly little effort has been devoted to measuring the effects of various counter-strategies. We address this void by running a pre-registered field experiment analyzing the causal effects of popular fact-checking videos on both believing and sharing fake news among Twitter users (N = 1,600). We find that the videos improve truth discernment ability as measured by performance in a fake news quiz immediately after exposure. However, the videos have not reduced sharing links from verified "fake news" websites on Twitter in the weeks following the exposure. Indeed, we find no relationship between truth discernment ability and fake news sharing. These results imply that the development of effective interventions should be based on a nuanced view of the distinct psychological motivations of sharing and believing "fake news".

Physical distancing is a crucial aspect of most countries’ strategies to manage the COVID-19 pandemic. However, keeping distance to others in public requires significant changes in conduct and behavior relative to ordinary circumstances. Throughout history, an effective strategy to make people engage in such behavioral change has been to morally condemn those who do not behave in an appropriate way. Accordingly, here, we investigate whether physical distancing has emerged as a moralized issue during the COVID-19 pandemic, potentially explaining the massive changes in behavior that have occurred across societies to halter the spread of the pandemic. Specifically, we utilize time-sensitive, representative survey evidence from eight Western democracies to examine the extent to which people (1) find it justified to condemn those who do not keep a distance to others in public and (2) blame ordinary citizens for the severity of the pandemic. The results demonstrate that physical distancing has indeed become a moral issue in most countries in the early phases of the pandemic. Furthermore, we identify the most important predictors of moralization to be age, behavioral change, social trust, and trust in the government. Except for minor differences, this pattern is observed within all countries in the sample. While moralization was high during the first wave of the pandemic, temporal analyses also indicate that moralization is lower in the second wave of the pandemic, potentially making it more difficult to engage in sufficient behavioral changes.