Table 5.
Number of persons vaccinated with MenB-4C vaccine who experienced postvaccination syncope or presyncope by timing of onset and dose number in the two-dose series.
| University A | University B | |||
|---|---|---|---|---|
| Onset | Dose 1 n (%) | Dose 2 n (%) | Dose 1 n (%) | Dose 2 n (%) |
| During 15-minute observation | ||||
| SyncopeA | 7 (0.10%) | 1 (0.02%) | 8 (0.08%) | 2 (0.03%) |
| PresyncopeA | 21 (0.29%) | 3 (0.05%) | 45 (0.46%) | 2 (0.03%) |
| Postvaccination days 0 and 1, excluding 15-minute observation | ||||
| Syncope | 1 (0.01%) | 1 (0.02%) | 5 (0.05%) | 1 (0.01%) |
| Presyncope | 0 | 4 (0.06%) | 5 (0.05%) | 1 (0.01%) |
| Postvaccination day ≥2B | ||||
| Syncope | 6 (0.08%) | 1 (0.02%) | 5 (0.05%) | 0 |
| Presyncope | 0 | 0 | 0 | 0 |
Note.
A
A case of syncope was defined as a brief loss of consciousness as evidenced by a loss of postural tone. A case of presyncope was defined as a person reporting that they felt like they were about to faint but who did not lose consciousness or postural tone. Symptoms such as dizziness that occurred in a person who did not report that they felt like they were about to faint were not counted as presyncope.
B
These syncope and presyncope events occurred from 2 to 53 days postvaccination.