Table 1.
Demographic characteristic and comorbidities of 1291 patients with 2009 H1N1 virus infection in China, May-July 2009. Figures are numbers (percentages) unless stated otherwise
| Characteristic | All patients (n=1291) | Children <15 years (n=406) | Adults ≥15 years (n=885) |
|---|---|---|---|
| Male | 701 (54) | 215 (53) | 486 (55) |
| Median (IQR) age (years) | 20 (12-26) | 9 (7-11) | 23 (19-33) |
| Age group (years): | |||
| 0-4 | 35 (3) | 35 (9) | — |
| 5-14 | 371 (29) | 371 (91) | — |
| 15-24 | 511 (40) | — | 511 (58) |
| 25-49 | 315 (24) | — | 315 (36) |
| 50-64 | 52 (4) | — | 52 (6) |
| ≥65 | 7 (0.5) | — | 7 (0.8) |
| Comorbidity associated with severe influenza*: | |||
| Any | 64 (5) | 14 (3) | 50 (6) |
| Asthma | 29 (2) | 13 (3) | 16 (2) |
| Other chronic pulmonary disease† | 10 (0.8) | 1 (0.2) | 9 (1) |
| Chronic liver disease | 10 (0.8)‡ | 0 (0) | 10 (1)‡ |
| Type 1 or 2 diabetes | 9 (0.7) | 1 (0.2) | 8 (0.9) |
| Coronary artery disease | 4 (0.3) | 0 (0) | 4 (0.5) |
| Pregnancy | 2 (0.2)§ | 0 (0) | 2 (0.2)§ |
| Chronic renal disease | 1 (0.1) | 0 (0) | 1 (0.1) |
| Immunosuppression | 1 (0.1)¶ | 0 (0) | 1 (0.1)¶ |
| Neurological disease | 0 (0) | 0 (0) | 0 (0) |
| Current smoker | 74/1176 (6) | 1/357 (0.3) | 73/819 (9) |
| Influenza vaccination, 2008-9 season | 30/515 (6) | 15/166 (9) | 15/349 (4) |
IQR=interquartile range.
*Comorbidities not mutually exclusive; some patients had multiple chronic comorbid diseases. Data unavailable for three children and three adults.
†Includes chronic bronchitis (5), emphysema (2), bronchiectasis (2), chronic bronchitis and bronchiectasis (1).
‡Includes hepatitis B and fatty liver.
§Both in second trimester (at 13 weeks’ gestation).
¶After heart transplantation.