Table 3:

Expected and observed rates of myocarditis with observed-to-expected ratios within a 21-day risk window after SARS-CoV-2 vaccination

	Observed*			Expected†			OE ratio (95% CI)
	No. of cases	No. of vaccine doses	Rate per 100 000 (95% CI)	No. of cases	Population	Rate per 100 000 (95% CI)
Overall	141	10 255 385	1.37 (1.16–1.62)	20.1	5 090 955	0.39 (0.26–0.63)	7.03 (5.92–8.29)
Sex
Male	105	4 891 011	2.15 (1.76–2.60)	7.1	2 571 779	0.28 (0.13–0.61)	14.76 (12.07–17.87)
Female	36	5 364 374	0.67 (0.47–0.93)	13.2	2 519 176	0.53 (0.30–0.93)	2.72 (1.91–3.77)
Age, yr
12–17	19	644 705	2.95 (1.77–4.60)	0.7	300 573	0.25 (0.01–1.85)	25.66 (15.45–40.07)
18–29	53	1 784 950	2.97 (2.22–3.88)	5.4	822 028	0.65 (0.27–1.59)	9.87 (7.39–12.9)
30–39	28	1 624 133	1.72 (1.15–2.49)	4.5	721 055	0.63 (0.23–1.62)	6.17 (4.10–8.92)
40–49	7	1 340 746	0.52 (0.21–1.08)	2.6	647 731	0.40 (0.10–1.35)	2.67 (1.07–5.50)
50–59	11	1 420 691	0.77 (0.39–1.39)	2.3	725 412	0.31 (0.09–1.21)	4.88 (2.44–8.73)
60–69	11	1 552 275	0.71 (0.35–1.27)	2.3	660 685	0.35 (0.09–1.33)	4.79 (2.39–8.56)
70–79	5	1 228 162	0.41 (0.13–0.95)	3.2	413 888	0.78 (0.26–2.47)	1.54 (0.50–3.60)
≥ 80	7	659 723	1.06 (0.43–2.19)	1.0	229 260	0.43 (0.01–2.43)	7.05 (2.83–14.52)
Vaccine
Pfizer	84	6 989 921	1.20 (0.96–1.49)	13.7	5 090 955	0.27 (0.15–0.46)	6.15 (4.90–7.61)
Moderna	57	3 265 464	1.75 (1.32–2.26)	6.4	5 090 955	0.13 (0.06–0.28)	8.93 (6.76–11.57)
Dose
Dose 1	26	3 994 380	0.65 (0.43–0.95)	7.8	5 090 955	0.15 (0.07–0.31)	3.33 (2.17–4.88)
Dose 2	88	3 884 987	2.27 (1.82–2.79)	7.6	5 090 955	0.15 (0.07–0.31)	11.59 (9.29–14.27)
Dose 3	27	2 376 018	1.14 (0.75–1.65)	4.6	5 090 955	0.09 (0.03–0.23)	5.81 (3.83–8.46)

Note: CI = confidence interval, Moderna = mRNA-1273 (Moderna), OE = observed-to-expected, Pfizer = BNT162b2 (Pfizer-BioNTech).

^*Myocarditis cases recorded within 21 days postvaccination between Dec. 15, 2020, and Mar. 31, 2022.

^†The background rates from 2019 were used to calculate the expected numbers.