Effects of Pathogen-Avoidance Tendency on Infection-Prevention Behaviors and Exclusionary Attitudes toward Foreigners: A Longitudinal Study of the COVID-19 Outbreak in Japan.

This study investigated the changes in public behaviors and attitudes following the spread of COVID-19 in Japan. Using a longitudinal approach that analyzes the movement of an unpredictable and real infection threat to explain and predict human behavior during the pandemic-a novel approach in behavioral immune system research-a panel survey was conducted on Japanese citizens. The results of the survey, conducted in late January, mid-February, and early March 2020, indicated that the influence of the interaction between the changes in situational infection threat and individual differences in pathogen-avoidance tendency on infection-prevention behaviors and exclusionary attitudes toward foreigners was not significant. Moreover, frequent contact with foreigners had a mitigating effect on exclusionary attitudes. The study thus provided a valuable contribution to the application of behavioral immune-system responses to problems associated with infection threats. Moreover, consideration of the aspects of adaptive reaction and social learning allowed us to observe the process of adaptive strategies in novel environments under conditions of high ecological validity and to accurately understand the psychological response to infectious disease outbreaks.