Immunological defence against pathogens and behavioural responses to members of other ethnic or racial groups may be understood as co-evolved solutions to a commonly recurring adaptive problem in our ancestral environment: the need to avoid infectious disease. In recent years, research on the concept of the behavioural immune system has highlighted behavioural defence, showing in particular that individual-level disgust sensitively is associated with greater prejudice towards members of other—particularly stigmatized—social groups. Stigma thus represents in part a human disease-avoidance strategy. This mechanism is thereby assumed to be particularly strong for individuals who report poor mental and/or physical health. In this article, we draw upon MIGHEAL data to examine how health vulnerabilities impact prejudice towards new immigrants in Greece—a key refugee- and migrant-receiving society. The findings have direct implications for the political consequences of health interventions: policies that result in enhanced immune-system functioning and resilience to health shocks may reduce prejudice towards new migrants, enhancing a society’s capacity to receive and integrate refugees and other migrants. Health policy may thus provide an avenue by which societies improve their responses to large-scale migration flows—a policy area that arguably represents the greatest moral crisis of our time.