Table 1.
Incidence of Influenza A virus infections among hospitalized pediatric ARI in different age groups
| Age group | Population* | Incidence per 100 000 population (95% CI) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Overall February 2007 to March 2011 | February 2007 to March 2008 | April 2008 to March 2009 | April 2009 to March 2010 | April 2010 to March 2011 | |||||||
| Months | n | Cases | Incidence | Cases | Incidence | Cases | Incidence | Cases | Incidence | Cases | Incidence |
| ≤11 | 2250 | 82 | 857 (693–1059) | 40 | 1422 (1047–1929) | 17 | 756 (472–1207) | 12 | 533 (305–930) | 13 | 578 (338–986) |
| 12–23 | 2431 | 117 | 1132 (948–1350) | 50 | 1645 (1251–2161) | 21 | 864 (566–1317) | 23 | 946 (631–1416) | 23 | 946 (631–1416) |
| 24–59 | 9254 | 119 | 303 (253–362) | 45 | 389 (291–520) | 28 | 303 (209–437) | 28 | 303 (209–437) | 18 | 195 (123–307) |
| <60 | 13 935 | 318 | 537 (482–598) | 135 | 775 (655–916) | 66 | 474 (372–602) | 63 | 452 (353–578) | 54 | 387 (297–505) |
| ≥60 | 38 690 | 36 | 22 (16–30) | 11 | 23 (13–41) | 7 | 18 (9–37) | 12 | 31 (18–54) | 6 | 16 (7–34) |
| Total | 48 260 | 354 | 173 (156–191) | 146 | 242 (206–285) | 73 | 151 (120–190) | 75 | 155 (124–195) | 60 | 124 (97–160) |
ARI, acute respiratory infection.
*
Data from population census survey in 2006.