Effectiveness of vaccination recommendations versus mandates: Evidence from the hepatitis A vaccine

I provide novel evidence on the effectiveness of two vaccination policies – simple non-binding recommendations to vaccinate versus mandates requiring vaccination prior to childcare or kindergarten attendance – in the context of the only disease whose institutional features permit a credible examination of both: hepatitis A. Using provider-verified immunization data I find that recommendations significantly increased hepatitis A vaccination rates among young children by at least 20 percentage points, while mandates increase rates by another 8 percentage points. These policies also significantly reduced population hepatitis A incidence. My results suggest a range of policy options for addressing suboptimally low population vaccination rates.