Vaccination and Risk Aversion: Evidence From a Flu Vaccination Campaign

We examine the causal effect of a French flu vaccination campaign on vaccination behavior. Individuals aged 65 and over receive an invitation letter with a voucher for a free flu shot, while those who are not eligible have to cover the costs themselves. Using a Fuzzy Regression Discontinuity Design, we find that receiving the invitation letter with the voucher leads to a significant increase in the likelihood of getting vaccinated. This effect is driven by individuals who are risk‐averse. As illustrated in our theoretical model, for them, the costs of influenza infection outweigh the costs of the vaccine's side effects.