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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Estimated herd immunity threshold (red line) based on R0 = 15.3, and numbers of secondary cases in each age sub-cohort if a single infectious individual had contact with the remaining susceptible individuals (Re).