Fig. 2

Cumulative number of averted SARS-CoV-2 infections owing to vaccination. The cumulative number of SARS-CoV-2-infected individuals in Tokyo from January 1 to May 27, 2022 in the counterfactual scenario in which (A) the primary series and booster programs had not taken place and (B) the booster program had not taken place, stratified by type of protection. The blue area represents empirically observed data (confirmed cases divided by an ascertainment bias factor of 25%), the pink area represents infections averted owing to a direct effect, and the green area represents infections averted owing to an indirect effect. The indirect effect was calculated as the gap between the total and direct effects. Dashed lines indicate the cumulative number of infections in the counterfactual scenario with no vaccination program