Table 4.
Serum HAI and MNt antibody responses to the heterologous H9N2 antigen, influenza A/Quail/Hong Kong/G1/97 (H9N2)
| Age group | 18–38 | 44–59 | ||||
|---|---|---|---|---|---|---|
| 7.5 mcg (n=31) | 30 mcg (n=30) | All (n=61) | 7.5 mcg (n=28) | 30 mcg (n=32) | All (n=60) | |
| HAI* | ||||||
| SCR (95% CI) | ||||||
| Day 28 | 14 (4, 33) | 30 (15, 49) | 22 (13, 35) | 21 (8, 41) | 13 (4, 29) | 17 (8, 29) |
| Day 56 | 11 (2, 29) | 24 (10, 44) | 18 (9, 30) | 12 (2, 30) | 13 (4, 29) | 12 (5, 23) |
| GMTs (95%CI) | ||||||
| Day 0 | 2 (2, 3) | 3 (2, 3) | 3 (2, 3) | 4 (3, 5) | 3 (3, 4) | 4 (3, 4) |
| Day 28 | 4 (3, 5) | 5 (3, 7) | 4 (3, 5) | 7 (5, 9) | 6 (5, 7) | 6 (5, 8) |
| Day 56 | 3 (3, 4) | 4 (3, 5) | 4 (3, 4) | 5 (4, 7) | 5 (4, 7) | 5 (4, 6) |
| SCF (95% CI) | ||||||
| Day 28 | 1.6 (1.2, 2.0) | 1.8 (1.4, 2.4) | 1.7 (1.4, 2.0) | 1.8 (1.4, 2.3) | 1.8 (1.4, 2.3) | 1.8 (1.5, 2.1) |
| Day 56 | 1.4 (1.1, 1.7) | 1.7 (1.3, 2.1) | 1.5 (1.3, 1.8) | 1.4 (1.1, 1.8) | 1.6 (1.3, 2.0) | 1.5 (1.3, 1.8) |
| % with titer ≥32 (95%CI) | ||||||
| Day 0 | 0 (0, 11) | 3 (0, 17) | 2 (0,9) | 4 (0,18) | 3 (0,16) | 3 (0,12) |
| Day 28 | 0 (0, 12) | 7 (1, 22) | 3 (0, 12) | 7 (1, 24) | 6 (1, 21) | 7 (2, 16) |
| Day 56 | 0 (0, 13) | 0 (0, 12) | 0 (0, 6) | 4 (0, 20) | 3 (0, 16) | 3 (0, 12) |
| MNt | ||||||
| SCR | ||||||
| Day 28 | 3 (0, 17) | 30 (15, 49) | 17 (8, 29) | 4 (0, 18) | 9 (2, 25) | 7 (2, 16) |
| Day 56 | 22 (9, 42) | 52 (33, 71) | 38 (25, 52) | 12 (2, 30) | 9 (2, 25) | 10 (4, 21) |
| GMTs (95%CI) | ||||||
| Day 0 | 3 (2, 4) | 3 (2, 4) | 3 (3, 4) | 10 (7, 14) | 10 (8, 12) | 10 (8, 12) |
| Day 28 | 6 (5, 7) | 9 (7, 13) | 7 (6, 9) | 15 (10, 22) | 16 (11, 22) | 15 (12, 20) |
| Day 56 | 7 (5, 9) | 10 (8, 13) | 8 (7, 10) | 18 (12, 26) | 17 (13, 23) | 17 (14, 22) |
| SCF (95% CI) | ||||||
| Day 28 | 1.8 (1.6, 2.1) | 2.8 (2.2, 3.6) | 2.3 (2.0, 2.6) | 1.5 (1.2, 1.9) | 1.6 (1.1, 2.2) | 1.6 (1.3, 1.9) |
| Day 56 | 2.1 (1.7, 2.6) | 3.4 (2.7, 4.3) | 2.7 (2.3, 3.2) | 1.8 (1.5, 2.2) | 1.7 (1.3, 2.3) | 1.8 (1.5, 2.1) |
*
Abbreviations: HAI = hemagglutination inhibition, GMT = geometric mean titer, SCF = seroconversion factor, SCR = seroconversion rate, MNt = microneutralization