Table 2.
Adjusted rVE of aIIV3 Versus Comparators During Restricted Influenza Seasons (Based on Peak Influenza Activity), by Age Groupa
| rVE (95% CI) | ||||
|---|---|---|---|---|
| aIIV3 vs: | Overall, Age ≥ 65 y | Age 65–74 y | Age 75–84 y | Age ≥ 85 y |
| December 11, 2017–March 18, 2018 | ||||
| IIV4 | 18.8 (16.3–21.3) | 16.5 (12.7–20.1) | 23.4 (19.4–27.2) | 20.4 (13.9–26.4) |
| HD-IIV3 | 8.2 (2.5–13.6) | 5.8 (–2.2 to 13.3) | 8.8 (–1.2 to 17.7) | 10.4 (–5.6 to 24.0) |
| December 17, 2018–April 7, 2019 | ||||
| IIV4 | 26.6 (23.8–29.4) | 29.2 (26.1–32.2) | 31.6 (27.5–35.6) | 25.2 (18.0–31.8) |
| HD-IIV3 | 5.7 (1.6–9.7) | 7.3 (1.6–12.7) | 10.6 (3.4–17.1) | 9.5 (–3.6 to 20.9) |
Abbreviations: aIIV3, adjuvanted trivalent inactivated influenza vaccine; CI, confidence interval; HD-IIV3, nonadjuvanted high-dose trivalent inactivated influenza vaccine; IIV4, nonadjuvanted quadrivalent inactivated influenza vaccine; rVE, relative vaccine effectiveness.
aAdjusted for age, sex, race, ethnicity, week of immunization and health status, and geographic region.