Number of swabs submitted, number (No) and percentage (%) positive for influenza virus and number (%) vaccinated by year, month of sample, age, sex and interval to swabbing
| Variable | Swabs submitted | No positive (% submitted) | No vaccinated (% submitted) |
| Year | |||
| 2005/06 | 946 | 282 (30%) | 151 (16%) |
| 2006/07 | 1408 | 401 (28%) | 194 (14%) |
| 2007/08 | 1152 | 280 (24%) | 176 (15%) |
| Month | |||
| Oct | 218 | 1 (0.5%) | 17 (8%) |
| Nov | 441 | 23 (5.0%) | 75 (17%) |
| Dec | 593 | 136 (23%) | 97 (16%) |
| Jan | 888 | 284 (32%) | 126 (14%) |
| Feb | 883 | 382 (43%) | 126 (14%) |
| Mar | 385 | 116 (30%) | 63 (16%) |
| Apr | 98 | 21 (21%) | 17 (17%) |
| Age group (years) | |||
| <5 | 358 | 70 (20%) | 11 (3%) |
| 5–14 | 404 | 173 (43%) | 13 (3%) |
| 15–44 | 1647 | 507 (31%) | 130 (8%) |
| 45–64 | 830 | 175 (21%) | 177 (21%) |
| ≥65 | 267 | 38 (14%) | 190 (71%) |
| Sex | |||
| Men | 1494 | 424 (28%) | 198 (18%) |
| Women | 1940 | 524 (27%) | 316 (24%) |
| Vaccinated | |||
| No | 2985 | 895 (30%) | – |
| Yes | 521 | 68 (13%) | – |
| Interval from illness onset to swab (days) | |||
| 0/1 | 449 | 130 (29%) | 61 (18%) |
| 2–4 | 1496 | 526 (35%) | 196 (24%) |
| 5–7 | 677 | 146 (22%) | 116 (18%) |
| 8–14 | 357 | 44 (12%) | 67 (24%) |
| 15–29 | 110 | 19 (17%) | 20 (18%) |