Multiple Group Membership, Optimistic Bias, and Infection Risk in the Context of Emerging Infectious Diseases

Abstract. Background: Understanding psychosocial factors which impact responses to emerging infectious diseases (EIDs) is vital in managing epidemics and pandemics. Two under-researched areas in this field are the interactive roles of optimistic bias (underestimation of the likelihood of negative events occurring to the self, relative to others) and group membership (a factor observed to be psychologically protective, but infection risk enhancing). Aims: The current study aimed to test the relationships between optimistic bias and membership of multiple groups upon EID-related emotional and psychological responses and behavioral intentions. Methods: Participants from the UK and US ( N = 360) rated how they would evaluate and respond to a fictitious EID immediately before the 2020 COVID-19 lockdowns in a correlational study. Results: Negative relationships were observed between optimistic bias and perceived infection vulnerability, infection prevention strategies, and perceived EID severity. Multiple group membership correlated negatively with germ avoidance, but positively with emotional responses such as disgust and increased perceived vulnerability to infection – factors linked to avoiding infection. Multiple group memberships and optimistic bias were unrelated. Limitations: The study focussed on a fictitious disease and relies on cross-sectional data and behavioral intentions. Conclusions: These findings build upon the small evidence base on the role of optimistic bias in EID management and suggest that multiple group membership is unlikely to increase optimistic bias. The theoretical and practical implications of the findings for EID management are discussed.