Abstract: The theory of Behavioral Immune System (BIS) posits that to cope with pandemic stress, human beings have evolved a series of behavioral responses, including vigilance to and disgust of disease cues, preference for healthy mate and collectivism, prejudice against out-groups and so on. For the first time, the existing studies were reviewed according to research level (individual vs. group). A large body of supportive evidence for BIS at both levels was identified, though many inconsistent and/or conflicting findings exist. Reasons leading to such inconsistencies include inadequacies of research methods, theory basis, and applicability in modern society. Future research should examine the boundary conditions of existing findings and theory; extend the scope of the current research; explore the underlying biological and physiological mechanism of BIS.

Key words: pathogen, behavioral immune system, infectious disease