Table 4.
Estimated vaccination efficacy in the Italian population aged >12 years in cases of COVID-19 cases diagnosed in the period 4 April–8 August 2021, with 95% confidence interval (Produced by the Istituto Superiore di Sanità (ISS), Rome. Data updated to 11 August 2021).
| Group | Age | Vaccination Efficacy % (Incomplete vs. Unvaccinated) * |
Vaccination Efficacy % (Complete vs. Unvaccinated) * |
|---|---|---|---|
| SARS-2 diagnosis | 12–39 | 41.34 (40.45–42.22) | 68.32 (67.6–69.02) |
| 40–59 | 66.63 (66.08–67.17) | 79.00 (78.59–79.41) | |
| 60–79 | 75.51 (75.05–75.96) | 88.01 (87.71–88.31) | |
| 80+ | 52.73 (51.2–54.22) | 88.91 (88.58–89.23) | |
| Total | 62.06 (61.71–62.41) | 82.33 (82.11–82.54) | |
| Hospitalizations | 12–39 | 79.27 (75.63–82.53) | 88.44 (85.42–91.00) |
| 40–59 | 89.49 (88.32–90.58) | 94.00 (93.09–94.82) | |
| 60–79 | 86.55 (85.8–87.26) | 95.53 (95.08–95.94) | |
| 80+ | 65.38 (63.27–67.38) | 94.07 (93.69–94.44) | |
| Total | 82.32 (81.68–82.95) | 94.7 (94.44–94.95) | |
| Intensive care admissions | 12–39 | - ** | - ** |
| 40–59 | 92.09 (88.51–94.82) | 97.15 (94.84–98.63) | |
| 60–79 | 90.57 (88.96–92.01) | 97.79 (96.94–98.46) | |
| 80+ | 74.86 (66.32–81.63) | 95.79 (94.22–97.01) | |
| Total | 89.4 (87.93–90.74) | 97.16 (96.49–97.74) | |
| Deaths | 12–39 | - ** | - ** |
| 40–59 | 86.82 (79.33–92.19) | 95.13 (89.47–98.26) | |
| 60–79 | 89.44 (87.98–90.76) | 96.89 (95.91–97.7) | |
| 80 * | 74.22 (71.74–76.53) | 96.69 (96.27–97.07) | |
| Total | 82.26 (80.91–83.53) | 96.82 (96.45–97.15) |
* Efficacy estimates with 95% confidence interval are shown in the table; ** estimates not calculable due to low frequency of events in some groups.