Research conducted at the outset of the pandemic shows that people are vulnerable to unrealistic optimism (UO). However, the Weinstein model suggests that this tendency may not persist as the pandemic progresses. Our research aimed at verifying whether UO persists during the second (Study 1) and the third wave (Study 2) of the pandemic in Poland, whether it concerns the assessment of the chances of COVID-19 infection (Study 1 and Study 2), the chances of severe course of the disease and adverse vaccine reactions (Study 2). We show that UO toward contracting COVID-19 persists throughout the pandemic. However, in situations where people have little influence on the occurrence of the event (chances of severe course of the disease and adverse vaccine reactions), the participants do not show UO. The exceptions are those who have personally known someone who has died from a coronavirus infection. These results are discussed in terms of self-esteem protection and the psychological threat reduction mechanism.
