Table 2. Estimated Vaccine Effectiveness against Covid-19 Outcomes during Three Time Periods.*.
| Period | Documented Infection | Symptomatic Illness | Hospitalization | Severe Disease | Death | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1−RR | Risk Difference | 1−RR | Risk Difference | 1−RR | Risk Difference | 1−RR | Risk Difference | 1−RR | Risk Difference | |
| % (95% CI) | no./1000 persons (95% CI) | % (95% CI) | no./1000 persons (95% CI) | % (95% CI) | no./1000 persons (95% CI) | % (95% CI) | no./1000 persons (95% CI) | % (95% CI) | no./1000 persons (95% CI) | |
| 14 to 20 days after first dose | 46 (40–51) |
2.06 (1.70–2.40) |
57 (50–63) |
1.54 (1.28–1.80) |
74 (56–86) |
0.21 (0.13–0.29) |
62 (39–80) |
0.14 (0.07–0.21) |
72 (19–100) |
0.03 (0.01–0.07) |
| 21 to 27 days after first dose | 60 (53–66) |
2.31 (1.96–2.69) |
66 (57–73) |
1.34 (1.09–1.62) |
78 (61–91) |
0.22 (0.13–0.31) |
80 (59–94) |
0.18 (0.10–0.27) |
84 (44–100) |
0.06 (0.02–0.11) |
| 7 days after second dose to end of follow-up | 92 (88–95) |
8.58 (6.22–11.18) |
94 (87–98) |
4.61 (3.29–6.53) |
87 (55–100) |
0.22 (0.08–0.39) |
92 (75–100) |
0.32 (0.13–0.52) |
NA | NA |
*
Confidence intervals were estimated using the percentile bootstrap method with 500 repetitions. Estimates were calculated only for cells with more than 10 instances of an outcome across the two groups. NA denotes not available, and RR risk ratio.