Persuasive messages will not raise COVID-19 vaccine acceptance. Evidence from a nation-wide online experiment

Although mass vaccination is the best way out of the pandemic, the share of sceptics is very substantial in most countries. Social campaigns can emphasize the many arguments that potentially raise acceptance for vaccines: e.g., that they have been developed, tested, and recommended by doctors and scientists; that they are safe, effective and in demand. We verified the effectiveness of such messages in an online experiment conducted in February and March 2021 with a sample of almost six thousand adult Poles, which was nationally representative in terms of key demographic variables. We presented responders with different sets of information about vaccination against COVID-19. After reading the information bundle, they indicated whether they would be willing to be vaccinated. We also asked them to justify their answers and indicate who or what might change their opinion. Finally, we elicited a number of individual characteristics and opinions. We found that nearly 45% of the responders were unwilling to be vaccinated and none of the popular messages we used was effective in reducing this hesitancy. We also observed a number of significant correlates of vaccination attitudes, with men, older, richer, and non-religious individuals, those with higher education, trusting science rather than COVID-19 conspiracy theories being more willing to be vaccinated. We discuss important consequences for campaigns aimed at reducing COVID-19 vaccine hesitancy.