INTERNATIONAL COMPARISONS OF THE BEHAVIORAL IMMUNE SYSTEM IN JAPAN, MALAYSIA AND THE PHILIPPINES

The purpose of this study was to examine the characteristics of the human behavioral immune system (BIS) by comparing its properties in three Asian countries (Japan, Malaysia, and the Philippines).A total of 1,142 university students completed paper-and-pencil questionnaires, including the Perceived Vulnerability to Disease questionnaire (PVD-Q), the Death Anxiety Scale, and a rating of their current subjective health status.Bayesian analyses were conducted on the valid data provided by 1,055 undergraduate students.Women were found to score higher than men on the germ aversion subscale of the PVD-Q (unpleasant feelings induced in contexts of a high potential for pathogen transmission), regardless of their nationality.In addition, participants from the tropical countries (Malaysia and the Philippines) scored higher in germ aversion compared to those from Japan, which is mostly in the temperate climate zone.No such significant sex and regional differences were observed on the other PVD-Q subscale (perceived infectability: beliefs about the susceptibility to infectious diseases).Perceived infectability was strongly associated with current health status, but less closely associated with fear of death, whereas germ aversion was highly associated with fear of death but not associated with health status.These associations between fear of death or health status and the PVD subscales were generally consistent across all three countries.The implication of these findings is that perceived infectability reflects an individual's proximate health-related beliefs or condition, while germ aversion rather reflects the ultimate evolutionary process of adaptation internalized in his or her mind.Anyway, both functions of the BIS seem to provide proactive defenses against pathogens in different ways.