Table 3.
Additional analysis; adjusted Third Dose Effectiveness (VE) against SARS-Cov2 infection, compared to second-dose only vaccinees.
| Exposure Groups/Booster Period | Cases | Controls | Adjusted Third Dose VE (%) for SARS-Cov2 Infection (CI 95%) |
|---|---|---|---|
| Second Dose Only | 7866 | 6264 | Reference |
| August 2021 (−5)‡ | 21,900 | 21,588 | 16 (12.3, 19.5) |
| September 2021 (−4)‡ | 25,920 | 25,623 | 18.3 (15.2, 21.2) |
| October 2021 (−3)‡ | 7378 | 8583 | 29.1 (26.1, 32) |
| November 2021 (−2)‡ | 872 | 1305 | 43.2 (38.2, 47.8) |
| December 2021 (−1)‡ | 491 | 1064 | 59.4 (54.9, 63.5) |
| 64,427 | 64,427 |
‡ Denotes the months prior to the outcome period. Therefore, those who received the booster in October 2021, received the third dose 3 months prior to the outcome period.