Table 1.
Comparison of cases testing positive for influenza A and B and test-negative cases
| Characteristic | Test-positive (n=662) | Test-negative (n=4737) | p-valuea |
|---|---|---|---|
| N (%) | N (%) | ||
| Age group | |||
| ≤2y | 264 (39.9%) | 2617 (55.2%) | <0.001 |
| 3–5y | 212 (32.0%) | 1269 (26.8%) | |
| 6–17y | 186 (28.1%) | 851 (18.0%) | |
| Male | 378 (57.1%) | 2749 (58.0%) | 0.679 |
| Receipt of TIV in the preceding 6 months | |||
| Yes | 32 (4.8%) | 428 (9.0%) | <0.001 |
| No | 630 (95.2%) | 4309 (91.0%) | |
| Receipt of monovalent H1N1pdm09 vaccine in the preceding 6 months | |||
| Yes (2009–10 only) | 3 (2.3%) | 36 (4.1%) | 0.465 |
| No (2009–10 only) | 130 (97.7%) | 850 (95.9%) |
a
p-values estimated by chi-squared tests (sex) and Fisher’s exact test (age group and vaccination history)