Table 2.
Comparison of adverse reaction severity between the monovalent and bivalent boosters.
| Monovalent booster (N = 317) | Bivalent booster (N = 114) | p-value | ||
|---|---|---|---|---|
| Local reactions (%) | ||||
| Pain at injection site | Mild (grade 1) | 127 (40.1) | 50 (43.9) | 0.480 |
| Moderate (grade 2) | 167 (52.7) | 52 (45.6) | 0.196 | |
| Severe (grade 3) | 20 (6.3) | 8 (7.0) | 0.694 | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 1.64 (1.58–1.71) | 1.56 (1.44–1.69) | 0.234 | |
| Redness | Mild (grade 1) | 96 (30.3) | 26 (22.8) | 0.129 |
| Moderate (grade 2) | 13 (4.1) | 1 (0.9) | 0.126 | |
| Severe (grade 3) | 0 (0) | 0 (0) | N/A | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 0.38 (0.32–0.45) | 0.25 (0.16–0.33) | 0.006 | |
| Swelling | Mild (grade 1) | 125 (39.4) | 39 (34.2) | 0.325 |
| Moderate (grade 2) | 26 (8.2) | 7 (6.1) | 0.478 | |
| Severe (grade 3) | 0 (0) | 0 (0) | N/A | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 0.56 (0.49–0.63) | 0.46 (0.35–0.58) | 0.178 | |
| Systemic reactions (%) | ||||
| Fever | 38.0 to 38.4°C (grade 1) | 45 (14.2) | 7 (6.1) | 0.024 |
| > 38.4 to 38.9°C (grade 2) | 25 (7.9) | 4 (3.5) | 0.110 | |
| > 38.9 to 40.0°C (grade 3) | 11 (3.5) | 3 (2.6) | 1.000 | |
| > 40.0°C (grade 4) | 3 (1.0) | 0 (0) | 0.569 | |
| Grade, mean (95 % CI) | 0.44 (0.35–0.54) | 0.21 (0.09–0.33) | 0.003 | |
| Fatigue | Mild (grade 1) | 100 (31.6) | 35 (30.7) | 0.868 |
| Moderate (grade 2) | 114 (36.0) | 46 (40.4) | 0.406 | |
| Severe (grade 3) | 54 (17.0) | 9 (7.9) | 0.018 | |
| Grade 4 | 1 (0.3) | 0 (0) | 1.000 | |
| Grade, mean (95 % CI) | 1.56 (1.45–1.66) | 1.35 (1.18–1.52) | 0.044 | |
| Headache | Mild (grade 1) | 91 (28.7) | 34 (29.8) | 0.822 |
| Moderate (grade 2) | 93 (29.3) | 27 (23.7) | 0.248 | |
| Severe (grade 3) | 31 (9.8) | 6 (5.3) | 0.140 | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 1.17 (1.06–1.28) | 0.93 (0.76–1.10) | 0.026 | |
| Chills | Mild (grade 1) | 65 (20.5) | 30 (26.3) | 0.199 |
| Moderate (grade 2) | 70 (22.1) | 14 (12.3) | 0.024 | |
| Severe (grade 3) | 32 (10.1) | 1 (0.9) | 0.002 | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 0.95 (0.83–1.07) | 0.54 (0.40–0.67) | < 0.001 | |
| Muscle Pain | Mild (grade 1) | 130 (41.0) | 50 (43.9) | 0.597 |
| Moderate (grade 2) | 118 (37.2) | 25 (21.9) | 0.003 | |
| Severe (grade 3) | 23 (7.3) | 6 (5.3) | 0.467 | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 1.37 (1.28–1.46) | 1.04 (0.88–1.19) | < 0.001 | |
| Joint Pain | Mild (grade 1) | 81 (25.6) | 30 (26.3) | 0.873 |
| Moderate (grade 2) | 71 (22.4) | 12 (10.5) | 0.006 | |
| Severe (grade 3) | 20 (6.3) | 3 (2.6) | 0.134 | |
| Grade 4 | 0 (0) | 0 (0) | N/A | |
| Grade, mean (95 % CI) | 0.89 (0.79–1.00) | 0.55 (0.41–0.70) | < 0.001 | |
| Use of medication | ||||
| Antipyretic use | No | 171 (53.9) | 58 (50.9) | 0.574 |
| Yes | 146 (46.1) | 56 (49.1) | ||
N/A; not available.