Experts and laypeople often describe pathogens and diseases by attributing to these nonhuman entities human-related qualities, mind states, intentions, and emotions (i.e., anthropomorphism). By taking advantage of the last pandemic, the present research was intended to investigate the implications of thinking about a virus in human-like terms for individuals' health-related behaviors. A severity pathway hypothesis (i.e., virus anthropomorphism is linked to higher engagement in preventive behaviors via higher perceived threat of the virus) and an effectiveness pathway hypothesis (i.e., virus anthropomorphism is associated with lower engagement in preventive behaviors via lower perceived effectiveness of such behaviors) were tested. Across two correlational studies (Study 1, N = 392; Study 2, N = 290), we found support only for the latter hypothesis. Study 2 further clarified the link assumed in the effectiveness pathway hypothesis, showing that anthropomorphism was associated with a decrease in the efficacy of preventive behaviors because attributing a mind to the virus diluted the relative sense of personal responsibility for contagion. A similar pattern of results emerged when we considered vaccination intention as the outcome.