What Activates the Behavioral Immune System During a Global Pandemic? Testing the Disgust Calibration Hypothesis

As a key part of the behavioral immune system, disgust is thought to have evolved to motivate the avoidance of pathogens. While evidence for such a role is accruing, naturalistic tests of this thesis are few and exactly how risk is implicated remains unclear. Two pre-registered studies tested whether objective or perceived risk for Covid-19 predicted daily reports of disgust in the first year of the pandemic. In study 1, n = 625 US adults (recruited via Qualtrics panels) completed up to10 daily diaries reporting disgust and perceived risk for contracting Covid-19 in March/April 2020. The Pandemic Vulnerability Index was used as an objective index of county-level risk at that time. Results based on pre-registered analyses indicated that perceived risk, but not objective risk, was associated with reported disgust. In study 2, n = 812 US adults completed similar procedures in January/February 2021. Again, perceived but not objective risk predicted disgust. These findings highlight the importance of considering objective versus subjective indicators of health risk when investigating how the disgust system adjusts in response to contextual inputs such as those evident during a global pandemic.