Characteristics of Hospitalized Patients by Influenza Type
| Characteristics | Influenza Typea | ||
|---|---|---|---|
| Influenza A (n = 2645) | Influenza B (n = 1510) | Unadjusted OR/P | |
| Boys | 1554 (58.8) | 875 (57.9) | 0.97 (0.85–1.10) |
| Age, y | |||
| Mean (SD) | 3.4 (3.9) | 5.0 (4.3) | <.0001 |
| Median (IQR) | 2.0 (0.6–4.8) | 3.9 (1.4–7.2) | <.0001 |
| Age group | <.0001 | ||
| 0–5 mo | 586 (22.2) | 170 (11.3) | — |
| 6–23 mo | 749 (28.3) | 305 (20.2) | — |
| 24–59 mo | 681 (25.7) | 423 (28.0) | — |
| 5–9 y | 406 (15.3) | 401 (26.6) | — |
| ≥10 y | 223 (8.4) | 211 (14.0) | — |
| Health status | .0004 | ||
| No underlying condition | 1342 (50.7) | 684 (45.3) | — |
| Vaccine-indicated condition | 976 (36.9) | 651 (43.1) | — |
| Other underlying condition | 327 (12.4) | 175 (11.6) | — |
| Ethnic originb | |||
| White | 532/845 (63.0) | 337/591 (57.0) | — |
| Asian | 92/845 (10.9) | 60/591 (10.2) | — |
| Middle Eastern | 51/845 (6.0) | 45/591 (7.6) | — |
| Black | 49/845 (5.8) | 74/591 (12.5) | — |
| Latin American | 17/845 (2.0) | 11/591 (1.9) | — |
| Aboriginal | 81/845 (9.6) | 46/591 (7.8) | — |
| Other/mixed | 23/845 (2.7) | 18/591 (3.0) | — |
| Data not available | 675 | 419 | — |
| Influenza vaccination statusc | |||
| Received influenza vaccine | 98/1504 (6.5) | 59/855 (6.9) | — |
| Data not available | 555 | 485 | — |
—, Inferential statistical analysis was not conducted.
↵a Data are n (column %) unless otherwise indicated; where fractions are shown, denominator is the number of cases with data available.
↵b Data available only for 2008–2009 season onward; n = 1520 (influenza A), n = 1010 (influenza B).
↵c Includes children ≥6 mo; n = 2059 (influenza A), n = 1340 (influenza B).