Vaccine Hesitancy and Betrayal Aversion

Current measures of vaccine hesitancy capture overall beliefs about the safety of vaccines without disassociating the source of the assumed risks. Betrayal aversion occurs when an individual is hesitant to risk being betrayed in an environment involving trust. In this pre-registered experimental study, we document the importance of betrayal aversion in vaccination decisions and show that it is not captured by current vaccine hesitancy measures. We find that over a third of participants have betrayal averse preferences, resulting in an 8-26% decline in vaccine acceptance, depending on the betrayal source. Moreover, we show that betrayal aversion is amplified in situations where the betrayal risk can be attributed to scientists or government. We explore an exogenous message intervention and show that an otherwise effective message acts narrowly and fails to reduce betrayal aversion. Our results demonstrate the importance of betrayal aversion as a preference construct in the decision to vaccinate.