Table 2. Reduction of influenza B cases achieved by use of QIV vs TIV, by group of age (over the 8 seasons; 2011–2018).
| TIV | Scenario 1 (QIV in eligible groups at current VCR) | Scenario 2 (QIV in <65y at current VCR, TIV in > = 65y at current VCR) | Scenario 3 (QIV in > = 65y at current VCR, TIV in <65y at current VCR) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Absolute difference | Absolute difference | Absolute difference | |||||||||||
| Age groups (years) | Current situation | New situation | Cases | Rate* | Relative difference | New situation | Cases | Rate* | Relative difference | New situation | Cases | Rate* | Relative difference |
| 0–1 | 35,478 | 31,138 | -4,340 | -579 | -12.2% | 34,720 | -758 | -101 | -2.1% | 31,578 | -3,900 | -520 | -11.0% |
| 2–4 | 105,386 | 92,614 | -12,772 | -1,110 | -12.1% | 103,194 | -2,192 | -190 | -2.1% | 93,899 | -11,487 | -998 | -10.9% |
| 5–14 | 992,130 | 873,200 | -118,930 | -2,817 | -12.0% | 971,289 | -20,841 | -494 | -2.1% | 885,930 | -106,200 | -2,516 | -10.7% |
| 15–19 | 689,546 | 612,093 | -77,453 | -3,527 | -11.2% | 675,819 | -13,727 | -625 | -2.0% | 621,033 | -68,513 | -3,120 | -9.9% |
| 20–49 | 2,876,028 | 2,513,312 | -362,716 | -2,122 | -12.6% | 2,810,320 | -65,708 | -384 | -2.3% | 2,552,559 | -323,469 | -1,893 | -11.2% |
| 50–64 | 1,022,743 | 865,327 | -157,416 | -1,733 | -15.4% | 981,888 | -40,855 | -450 | -4.0% | 888,675 | -134,068 | -1,476 | -13.1% |
| 65–69 | 195,966 | 148,505 | -47,461 | -1,575 | -24.2% | 190,207 | -5,759 | -191 | -2.9% | 150,659 | -45,307 | -1,504 | -23.1% |
| 70–74 | 277,914 | 214,001 | -63,913 | -2,222 | -23.0% | 270,283 | -7,631 | -265 | -2.7% | 217,052 | -60,862 | -2,115 | -21.9% |
| 75+ | 1,048,624 | 783,971 | -264,653 | -2,355 | -25.2% | 1,019,038 | -29,586 | -263 | -2.8% | 795,750 | -252,874 | -2,250 | -24.1% |
| Total | 7,243,815 | 6,134,161 | -1,109,654 | -2,150 | -15.3% | 7,056,758 | -187,057 | -362 | -2.6% | 6,237,135 | -1,006,680 | -1,950 | -13.9% |
QIV: quadrivalent influenza vaccine; TIV: trivalent influenza vaccine; VCR: vaccination coverage rate.
*Rate per 100,000