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Proportion and 95% confidence interval of the study population newly infected per epidemic period, by age group, and overall. Period 1 approximately covers infections from late‐February 2020 to mid‐June 2020, period 2 from mid‐June 2020 to mid‐February 2021, and period 3 from mid‐February 2021 to late‐June 2021. Absolute numbers are available in Tables S1–S3.
