Simon-Makuch hazard plot comparing the cumulative incidence of COVID-19 in the “up-to-date” and “not up-to-date” states with respect to COVID-19 vaccination, stratified by the phase during which the last prior episode of COVID-19 occurred.

Day zero was 29 January 2023, the day the XBB lineages of the Omicron variant became the dominant strains in Ohio. Point estimates and 95% confidence intervals are jittered along the x-axis to improve visibility. “Remote infection” includes infections during the pre-Omicron and Omicron BA.1/BA.2 dominant periods, i.e more than 218 days before the study start date. Solid lines represent the “up-to-date” states while dashed lines represent the “not up-to-date” states.