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. 2022 Jan 20;116:365–373. doi: 10.1016/j.ijid.2022.01.036

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Relationship between primary and secondary cases by age group and gender for each phase. The color scale shows the proportion of observed total transmission pairs in each phase. Note that the color scales are different between phases 1, 2, and 4 and phases 3.

F, female; M, male.