Age (mth) | Exposure time (child years) | Observed cases (number of true vaccine failures) | Expected cases* (number) | % effectiveness | 95% CI |
---|---|---|---|---|---|
*Based on incidence rates observed prior to the vaccine era. | |||||
5–11 | 3 155 698 | 22 | 3437 | 99.4 | 99.0, 99.6 |
12–23 | 4 751 048 | 51 | 2376 | 97.9 | 97.2, 98.4 |
24–35 | 4 096 310 | 47 | 1037 | 95.5 | 93.9, 96.7 |
36–47 | 3 435 236 | 30 | 618 | 95.1 | 93.0, 96.8 |
48–59 | 2 766 590 | 15 | 149 | 89.9 | 82.9, 94.5 |
60–71 | 2 087 099 | 3 | 102 | 97.1 | 91.2, 99.4 |
All ages | 21 698 320 | 171 | 6509 | 97.4 | 96.9, 97.8 |