Investigation of the Moderating Role of Perceived Vulnerability to Infectious Diseases Regarding the Relationship between Disgust and Fear of Contamination

Background and Objective: Several studies revealed that disgust as an emotional response underlies the contamination fears in Contamination Obsessive Compulsive Disorder (OCD). Other studies supported the role of cognitions related to contagion and disease in contamination OCD. The present study aimed to integrate these two lines of evidence. To this end, regarding the concept of the behavioral immune system, it was investigated whether perceived vulnerability to infectious disease, as a cognitive component of the behavioral immune system, can moderate the relation between disgust, as the emotional component of this system, and symptoms of contamination OCD. Materials and Methods: This cross-sectional study was conducted on 350 university students in Tehran University through cluster random sampling. The participants were asked to complete the Persian version of the disgust scale, perceived vulnerability to disease questionnaire, and Vancouver contamination subscale. The data were analyzed utilizing hierarchical regression analysis and post hoc tests.  Results: The results revealed that perceived vulnerability to infectious disease moderated the relationship between the feeling of disgust and fear of contamination.  According to the results, perceived infectability subscale which measures perceived weakness of one's immune system with more accuracy, can also exacerbate the relationship between the feeling of disgust and fear of contamination. Conclusion: The results of this study facilitate the understanding of the effect of disgust on fear of contamination, especially the role of cognitions about contagion and disease in potentiating the relation between disgust and contamination OCD. Moreover the obtained results generally provide evidence for the disease-avoidance theory in disgust and support the possible hyperactivity of the behavioral immune system in contamination OCD.