Table 2.
Proportions of Subjects With HAI Titers ≥32 or NAI Titers ≥40 at Prevaccination, and 1, 6, 12, and 18 Month Postvaccination Time Points by Intervention
| Intervention and Antigen | Months Following Vaccination |
||||
|---|---|---|---|---|---|
| 0 | 1 | 6 | 12 | 18 | |
| IIV | |||||
| Influenza A (H3N2) HAI, % | 55.9 | 97.0 | 92.8 | 89.3 | 89.1 |
| Influenza A (H3N2) NAI, % | 37.7 | 79.1 | 59.8 | 57.0 | 48.0 |
| Influenza B HAI, % | 77.8 | 99.8 | 98.4 | 97.2 | 95.6 |
| LAIV | |||||
| Influenza A (H3N2) HAI, % | 44.9 | 68.0 | 61.7 | 62.7 | 59.3 |
| Influenza A (H3N2) NAI, % | 29.8 | 40.4 | 39.4 | 38.5 | 32.2 |
| Influenza B HAI, % | 68.8 | 92.1 | 89.8 | 84.0 | 81.9 |
| Placebo | |||||
| Influenza A (H3N2) HAI, % | 48.1 | 44.2 | 44.2 | 49.6 | 45.7 |
| Influenza A (H3N2) NAI, % | 32.1 | 36.9 | 29.8 | 32.1 | 28.6 |
| Influenza B HAI, % | 67.4 | 72.9 | 69.8 | 69.8 | 67.4 |
Abbreviations: HAI, hemagglutination inhibition; IIV, inactivated influenza vaccine; LAIV, live attenuated influenza vaccine; NAI, neuraminidase inhibition.