Table 3.
Incidence rates of adverse effects in the 7 days following the date of the first BNT162b2 or mRNA-1273 dose
| Vaccine | Adverse effect | Vaccinated incidence rate, cases/person-days [cases per 1,000 person-days] | Unvaccinated incidence rate, cases/person-days [cases per 1,000 person-days] | IRR (95% CI) |
|---|---|---|---|---|
| BNT162b2 (51,795 individuals per cohort) | anaphylaxis | 11/361,515 [0.03] | 17/359,538 [0.047] | 0.64 (0.27, 1.5) |
| arthralgia | 360/360,052 [1] | 261/358,536 [0.73] | 1.4 (1.2, 1.6) | |
| chills | 67/361,310 [0.19] | 96/359,211 [0.27] | 0.69 (0.5, 0.96) | |
| CVST | 0/361,565 [0] | 2/359,600 [0.0056] | 0 (0, 5.3) | |
| diarrhea | 183/360,859 [0.51] | 312/358,329 [0.87] | 0.58 (0.48, 0.7) | |
| erythema | 273/360,470 [0.76] | 283/358,459 [0.79] | 0.96 (0.81, 1.1) | |
| facial paralysis | 4/361,554 [0.011] | 10/359,560 [0.028] | 0.4 (0.091, 1.4) | |
| fatigue | 470/359,712 [1.3] | 638/356,984 [1.8] | 0.73 (0.65, 0.82) | |
| fever | 128/361,104 [0.35] | 181/358,857 [0.5] | 0.7 (0.56, 0.89) | |
| headache | 522/359,506 [1.5] | 571/357,234 [1.6] | 0.91 (0.81, 1) | |
| local pain | 3/361,553 [0.0083] | 1/359,604 [0.0028] | 3 (0.24, 160) | |
| local swelling | 2/361,560 [0.0055] | 0/359,610 [0] | inf (0.19, inf) | |
| lymphadenopathy | 114/361,137 [0.32] | 141/359,015 [0.39] | 0.8 (0.62, 1) | |
| myalgia | 381/360,002 [1.1] | 294/358,405 [0.82] | 1.3 (1.1, 1.5) | |
| nausea | 332/360,302 [0.92] | 495/357,565 [1.4] | 0.67 (0.58, 0.77) | |
| soreness | 116/361,049 [0.32] | 85/359,252 [0.24] | 1.4 (1, 1.8) | |
| vomiting | 128/361,057 [0.35] | 270/358,495 [0.75] | 0.47 (0.38, 0.58) | |
| mRNA-1273 (16,471 individuals per cohort) | anaphylaxis | 2/114,990 [0.017] | 8/114,619 [0.07] | 0.25 (0.026, 1.2) |
| arthralgia | 188/114,237 [1.6] | 107/114,227 [0.94] | 1.8 (1.4, 2.2) | |
| chills | 29/114,900 [0.25] | 28/114,538 [0.24] | 1 (0.59, 1.8) | |
| CVST | 0/114,994 [0] | 1/114,643 [0.0087] | 0 (0, 39) | |
| diarrhea | 80/114,685 [0.7] | 127/114,163 [1.1] | 0.63 (0.47, 0.84) | |
| erythema | 124/114,467 [1.1] | 95/114,251 [0.83] | 1.3 (0.99, 1.7) | |
| facial paralysis | 1/114,992 [0.0087] | 4/114,637 [0.035] | 0.25 (0.0051, 2.5) | |
| fatigue | 244/114,010 [2.1] | 277/113,561 [2.4] | 0.88 (0.74, 1) | |
| fever | 62/114,781 [0.54] | 80/114,328 [0.7] | 0.77 (0.54, 1.1) | |
| headache | 187/114,286 [1.6] | 188/113,908 [1.7] | 0.99 (0.81, 1.2) | |
| local pain | 2/114,983 [0.017] | 0/114,644 [0] | inf (0.19, inf) | |
| local swelling | 0/114,994 [0] | 0/114,644 [0] | N/A | |
| lymphadenopathy | 80/114,688 [0.7] | 60/114,429 [0.52] | 1.3 (0.94, 1.9) | |
| myalgia | 165/114,290 [1.4] | 111/114,241 [0.97] | 1.5 (1.2, 1.9) | |
| nausea | 155/114,400 [1.4] | 188/113,947 [1.6] | 0.82 (0.66, 1) | |
| soreness | 42/114,845 [0.37] | 32/114,524 [0.28] | 1.3 (0.81, 2.1) | |
| vomiting | 69/114,744 [0.6] | 101/114,299 [0.88] | 0.68 (0.49, 0.93) |
For each adverse effect, incidence rates were calculated for the vaccinated and propensity-matched unvaccinated cohorts as the number of positive cases divided by the total number of at-risk person-days during this time period. Individuals were considered at risk for developing an adverse effect from their actual or assigned date of first vaccination until they experienced the event, died, or reached the end of the 7-day study period or until 4 days prior to a positive SARS-CoV-2 test result. For example, we see that 470 cases of fatigue were recorded in the BNT162b2-vaccinated cohort over a total of 359,712 person-days, corresponding to an incidence rate of 1.3 cases per 1,000 person-days. N/A, not applicable; inf, infinity.