Table 1. Estimated proportion of infections caused by each age group.

Rows show the receiving (i.e., infectee) age groups, and columns show the sources of infection (i.e., infector age groups). The numbers are the mean (95% CrI) estimates in percentage. For instance, for <1-year-olds (top row), on average, 16.3% of cases were infected by the same age group, 44.6% by 1- to 4-year-olds, 20.9% by 5- to 17-year-olds, 15.2% by 18- to 49-year-olds, and 3% by 50+-year-olds.

Infectee age groups	Infector age groups
	<1 year	1–4 years	5–17 years	18–49 years	50+ years
<1 year	16.3 (12.3–21.0)	44.6 (35.5–53.5)	20.9 (13.9–28.4)	15.2 (9.6–21.6)	3.0 (1.4–5.0)
1–4 years	1.8 (1.0–3.0)	85.8 (77.0–91.9)	7 (3.2–12.9)	5 (2.2–9.3)	0.3 (0.1–0.6)
5–17 years	1.5 (0.9–2.4)	12.9 (6.9–21.3)	80.9 (70.4–88.4)	4.4 (2.0–8.0)	0.3 (0.1–0.5)
18–49 years	2.4 (1.5–3.7)	18.6 (10.9–28.0)	9.1 (4.8–14.9)	69.5 (56.2–80.8)	0.4 (0.2–0.8)
50+ years	15.5 (11.6–19.9)	40.1 (31.1–49.3)	19.7 (13.0–27.0)	15.6 (9.7–22.4)	9.1 (3.8–16.3)