TABLE 3.
Odds ratios for seroresponse and seroprotection proportions after the first vaccinationf
| Vaccine antigen and category | Seroresponse (S1/S0 ≥ 4) |
Seroprotection (S1 ≥ 1:40) |
||||||
|---|---|---|---|---|---|---|---|---|
| Total no. of subjects | No. (%) with seroresponse | OR (95% CI)a |
Total no. of subjects | No. (%) with seroprotection | OR (95% CI)a |
|||
| Crude | Adjustedb | Crude | Adjustedb | |||||
| A/New Caledonia/20/99(H1N1) | ||||||||
| Prevaccination titer | ||||||||
| <1:10 | 200 | 90 (45) | 1.0 | 1.0 | 200 | 65 (33) | 1.0 | 1.0 |
| 1:10–1:20 | 44 | 38 (86) | 7.7 (3.1, 19.1) | 2.2 (0.8, 5.8) | 44 | 42 (95) | 43.6 (10.2, 186) | 5.4 (2.1, 13.6) |
| ≥1:40 | 15 | 5 (33) | 0.6 (0.2, 1.9) | 0.14 (0.04, 0.49) | ||||
| Ptrend | —c | |||||||
| Age | ||||||||
| 0 yr | 64 | 6 (9) | 0.01 (0.01, 0.08) | 0.03 (0.01, 0.07) | 63 | 2 (3) | 0.01 (0.003, 0.05) | 0.03 (0.01, 0.1) |
| 1 yr | 65 | 26 (40) | 0.2 (0.1, 0.4) | 0.17 (0.08, 0.34) | 65 | 18 (28) | 0.13 (0.06, 0.25) | 0.2 (0.1, 0.4) |
| 2–3 yr | 130 | 101 (78) | 1.0 | 1.0 | 116 | 87 (75) | 1.0 | 1.0 |
| Ptrend | —d | —d | —d | —d | ||||
| A/New York/55/2004 (H3N2) | ||||||||
| Prevaccination titer | ||||||||
| <1:10 | 187 | 63 (34) | 1.0 | 1.0 | 187 | 41 (22) | 1.0 | 1.0 |
| 1:10–1:20 | 9 | 8 (89) | 15.8 (1.9, 129) | 8.8 (1.1, 73.1) | 9 | 8 (89) | 28.5 (3.5, 234) | 16.3 (1.8, 148) |
| ≥1:40 | 63 | 39 (62) | 3.2 (1.8, 5.8) | 1.7 (0.9, 3.3) | ||||
| Ptrend | —d | |||||||
| Age | ||||||||
| 0 yr | 64 | 7 (11) | 0.08 (0.04, 0.19) | 0.11 (0.04, 0.26) | 62 | 0 | NA | NA |
| 1 yr | 65 | 29 (45) | 0.4 (0.2, 0.8) | 0.5 (0.3, 0.9) | 56 | 9 (16) | 0.18 (0.08, 0.42) | 0.18 (0.08, 0.44) |
| 2–3 yr | 130 | 78 (60) | 1.0 | 1.0 | 78 | 40 (51) | 1.0 | 1.0 |
| Ptrend | —d | —d | ||||||
| B/Shanghai/361/2002 | ||||||||
| Prevaccination titer | ||||||||
| <1:10 | 188 | 59 (31) | 1.0 | 1.0 | 188 | 39 (21) | 1.0 | 1.0 |
| 1:10–1:20 | 40 | 34 (85) | 12.4 (4.9, 31.1) | 9.2 (3.2, 26.6) | 40 | 37 (93) | 47.1 (13.8, 161) | 47.5 (11.5, 197) |
| ≥1:40 | 31 | 18 (58) | 3.0 (1.4, 6.6) | 1.5 (0.7, 3.4) | ||||
| Ptrend | —d | —e | ||||||
| Age | ||||||||
| 0 yr | 64 | 3 (5) | 0.03 (0.01, 0.09) | 0.03 (0.01, 0.11) | 64 | 3 (5) | 0.04 (0.01, 0.14) | 0.04 (0.01, 0.17) |
| 1 yr | 65 | 23 (35) | 0.3 (0.2, 0.5) | 0.4 (0.2, 0.7) | 65 | 23 (35) | 0.3 (0.1, 0.5) | 0.3 (0.1, 0.8) |
| 2–3 yr | 130 | 85 (65) | 1.0 | 1.0 | 130 | 85 (65) | 1.0 | 1.0 |
| Ptrend | —d | —d | —d | —d | ||||
a
OR, odds ratio; CI, confidence interval.
b
Adjusted for prevaccination titer and age.
c
P < 0.05.
d
P < 0.001.
e
P < 0.01.
f
Subjects with prevaccination titer of ≥1:40 were excluded from the seroprotection analyses.