TABLE 2.
Baseline strain-specific HAI titer distributions
| Age group and HAI titera | No. (%) of subjects
|
|||||
|---|---|---|---|---|---|---|
| CAIV-T
|
LAIV
|
|||||
| H1N1 | H3N2 | B | H1N1 | H3N2 | B | |
| 5 to 8 yr | 176 | 176 | 176 | 182 | 182 | 182 |
| ≤1:4 | 61 (34.7) | 9 (5.1) | 141 (80.1) | 65 (35.7) | 11 (6.0) | 134 (73.6) |
| 1:8 | 15 (8.5) | 0 (0.0) | 16 (9.1) | 28 (15.4) | 3 (1.6) | 23 (12.6) |
| 1:16 | 44 (25.0) | 4 (2.3) | 12 (6.8) | 43 (23.6) | 6 (3.3) | 12 (6.6) |
| 1:32 | 33 (18.8) | 17 (9.7) | 5 (2.8) | 29 (15.9) | 19 (10.4) | 8 (4.4) |
| 1:64 | 14 (8.0) | 38 (21.6) | 2 (1.1) | 10 (5.5) | 39 (21.4) | 4 (2.2) |
| 1:128 | 5 (2.8) | 48 (27.3) | 0 (0.0) | 6 (3.3) | 55 (30.2) | 1 (0.5) |
| 1:256 | 3 (1.7) | 52 (29.5) | 0 (0.0) | 1 (0.5) | 41 (22.5) | 0 (0.0) |
| 1:512 | 1 (0.6) | 8 (4.5) | 0 (0.0) | 0 (0.0) | 8 (4.4) | 0 (0.0) |
| GMT | 11.01 | 97.16 | 3.17 | 9.14 | 82.29 | 3.65 |
| 9 to 49 yr | 280 | 280 | 280 | 279 | 279 | 279 |
| ≤1:8 | 170 (60.7) | 54 (19.3) | 166 (59.3) | 174 (62.4) | 64 (22.9) | 174 (62.4) |
| 1:16 | 27 (9.6) | 25 (8.9) | 41 (14.6) | 33 (11.8) | 28 (10.0) | 40 (14.3) |
| 1:32 | 29 (10.4) | 45 (16.1) | 33 (11.8) | 28 (10.0) | 44 (15.8) | 24 (8.6) |
| 1:64 | 25 (8.9) | 55 (19.6) | 23 (8.2) | 17 (6.1) | 46 (16.5) | 28 (10.0) |
| 1:128 | 14 (5.0) | 49 (17.5) | 10 (3.6) | 11 (3.9) | 49 (17.6) | 10 (3.6) |
| 1:256 | 9 (3.2) | 33 (11.8) | 7 (2.5) | 11 (3.9) | 30 (10.8) | 3 (1.1) |
| 1:512 | 5 (1.8) | 15 (5.4) | 0 (0.0) | 4 (1.4) | 15 (5.4) | 0 (0.0) |
| 1:1,024 | 1 (0.4) | 4 (1.4) | 0 (0.0) | 1 (0.4) | 3 (1.1) | 0 (0.0) |
| GMT | 9.26 | 45.93 | 8.64 | 8.22 | 40.62 | 7.88 |
a
Seronegative was defined for 5- to 8-year-old children as a baseline strain-specific HAI titer of ≤1:4; serosusceptible was defined for 9- to 49-year-old children and adults as a baseline strain-specific HAI titer of ≤1:8.