Table 1.
Number of cases of myo/pericarditis per million mRNA vaccine doses, compared to expected rates in the US general population stratified by age, sex, vaccine dose (first or second), and vaccine type.
| Sex | Number of Doses/ Observed No. of Cases |
Age (Years) | ||||||
|---|---|---|---|---|---|---|---|---|
| 12–17 | 18–29 | 30–39 | 40–49 | 50–64 | 65+ | All | ||
| Pfizer-BioNTech ( Comirnaty) | ||||||||
| Males | Number of first doses | 4,130,345 | 6,416,041 | 6,274,534 | 6,307,233 | 11,537,946 | 11,593,304 | 46,259,406 |
| Observed no. of cases | 62 | 51 | 25 | 10 | 16 | 18 | 182 | |
| Observed no. of cases per million doses * | 15.0 | 7.9 | 4.0 | 1.6 | 1.4 | 1.6 | 3.9 | |
| Number of second doses | 3,105,286 | 5,158,756 | 5,212,165 | 5,354,938 | 9,999,709 | 10,237,134 | 39,067,988 | |
| Observed no. of cases | 205 | 180 | 53 | 37 | 25 | 17 | 517 | |
| Observed no. of cases per million doses * | 66.0 | 34.9 | 10.2 | 6.9 | 2.5 | 1.7 | 13.2 | |
| Females | Number of first doses | 4,370,879 | 7,474,687 | 6,962,009 | 7,197,081 | 13,146,233 | 14,065,052 | 53,215,944 |
| Observed no. of cases | 12 | 15 | 16 | 13 | 25 | 15 | 96 | |
| Observed no. of cases per million doses * | 2.7 | 2.0 | 2.3 | 1.8 | 1.9 | 1.1 | 1.8 | |
| Number of second doses | 3,333,409 | 6,229,183 | 5,968,924 | 6,197,721 | 11,500,977 | 12,318,105 | 45,548,323 | |
| Observed number of cases | 28 | 27 | 16 | 25 | 28 | 10 | 134 | |
| Observed no. of cases per million doses * | 8.4 | 4.3 | 2.7 | 4.0 | 2.4 | 0.8 | 2.9 | |
| Moderna (Spikevax) | ||||||||
| Males | Number of first doses | NA | 5,362,926 | 4,858,349 | 5,086,879 | 9,161,298 | 9,530,389 | 33,999,843 |
| Observed no. of cases | 47 | 20 | 13 | 17 | 11 | 108 | ||
| Observed no. of cases per million doses * | 8.8 | 4.1 | 2.6 | 1.9 | 1.2 | 3.2 | ||
| Number of second doses | NA | 4,364,363 | 4,024,907 | 4,279,450 | 7,919,481 | 8,335,937 | 28,924,140 | |
| Observed no. of cases | 137 | 44 | 20 | 18 | 20 | 239 | ||
| Observed no. of cases per million doses * | 31.4 | 10.9 | 4.7 | 2.3 | 2.4 | 8.3 | ||
| Females | Number of first doses | NA | 5,675,241 | 5,659,976 | 5,644,228 | 10,453,808 | 10,858,841 | 38,292,095 |
| Observed no. of cases | 15 | 16 | 6 | 17 | 14 | 68 | ||
| Observed no. of cases per million doses * | 2.6 | 2.8 | 1.1 | 1.6 | 1.3 | 1.8 | ||
| Number of second doses | NA | 4,684,982 | 4,860,065 | 4,900,788 | 9,165,884 | 9,587,422 | 33,199,143 | |
| Observed number of cases | 16 | 8 | 16 | 22 | 11 | 73 | ||
| Observed no. of cases per million doses * | 3.4 | 1.6 | 3.3 | 2.4 | 1.1 | 2.2 | ||
* Observed no. of cases per million doses outside of expected range 0.12–2.36 for males and 0.07–1.47 for females in the general population prior to the administration of the first COVID-19 vaccines in December 2020 are marked in bold type. Background rates of myo/pericarditis are based on results observed in multiple studies synthesized by Willame et al. [19]. Abbreviations: N/A, not applicable (Moderna COVID-19 vaccine not approved for this age group as of 31 July 2021).