Table 5. Effect of current and previous influenza vaccination in patients ≥9 years by virus type/subtype in Spain, seasons 2010–2011 to 2015–2016.
| Type/ subtype | Season | Vaccine and circulating strains | Unvaccinated | Vaccinated previous season only |
Vaccinated current season only | Vaccinated both seasons | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Previous season vaccine strain | Current season vaccine strain |
Main Circulating strain |
Cases/ Controls |
Cases/ Controls |
VEa (95%CI) | Cases/ Controls |
VEa (95%CI) | Cases/ Controls | VEa (95%CI) | ||
| A(H1N1)pdm09 | 2010–2011 | A/California/7/2009 | A/California/7/2009 | A/California/7/2009b | 474/355 | 5/11 | 65 (-13; 89) | 18/35 | 45 (-11; 73) | 4/19 | 73 (1; 93) |
| 2013–2014 | A/California/7/2009 | A/California/7/2009 | A/StPetersburg/27/2011b | 276/376 | 5/10 | 20 (-147; 74) | 5/8 | 0 (-234; 70) | 17/50 | 46 (-5; 73) | |
| 2015–2016 | A/California/7/2009 | A/California/7/2009 | A/SouthAfrica/3626/2013b | 356/219 | 9/4 | -55 (-446; 66) | 4/10 | 74 (11; 92) | 26/32 | 49 (-5; 75) | |
| Pooled analysis | 1106/950 | 19/25 | 26 (-39; 61) | 27/53 | 53 (21; 72) | 47/101 | 50 (23; 68) | ||||
| A(H3N2) | 2011–2012 | A/Perth/16/2009 | A/Perth/16/2009 | 40%:A/England/259/2011c 36%:A/Victoria/361/2011c 22%: A/Iowa/19/2010c |
564/364 | 8/7 | 45 (-55; 89) | 17/10 | 14 (-107;65) | 83/49 | 34 (-6; 59) |
| 2013–2014 | A/Texas/50/2012 | A/Texas/50/2012d | A/Texas/50/2012b | 268/372 | 5/10 | 26 (-132; 77) | 7/8 | -1 (203;66) | 42/50 | -20 (-115;34) | |
| 2014–2015 | A/Texas/50/2012 | A/Texas/50/2012 | 35% A/Samara/73/2013b 50%A/HongKong/5738/2014c 15%A/Switzerland/9715293/2013c |
311/313 | 4/4 | -29 (-507; 72) | 6/11 | 45 (-59;80) | 41/30 | -45 (-171;21) | |
| Pooled analysis | 1143/1049 | 17/21 | 23 (-51; 61) | 30/29 | 17 (-43;52) | 166/129 | 3 (-33; 28) | ||||
| B | 2010–2011 | B/Brisbane/60/2008 (lin. Victoria) |
B/Brisbane/60/2008 (lin. Victoria) |
B/Brisbane/60/2008b (lin. Victoria) |
111/393 | 4/13 | -62 (-544; 69) | 2/14 | 51 (-182;91) | 7/46 | 62 (-13; 87) |
| 2012–2013 | B/Brisbane/60/2008 (lin. Victoria) |
B/Wisconsin/1/2010 (lin. Yamagata) |
B/Estonia/55669/2012b B/Wisconsin/1/2010b (lin. Yamagata) |
472/372 | 8/5 | -53 (-396; 53) | 6/7 | 44 (-84; 83) | 25/51 | 67 (40; 82) | |
| 2014–2015 | B/Massachusetts/02/2012 (lin. Yamagata) |
B/Massachusetts/02/2012 (lin. Yamagata) |
B/Phuket/3073/2013b (lin. Yamagata) |
275/314 | 4/4 | -22 (-416; 71) | 3/11 | 66 (-28; 91) | 19/31 | 30 (-40; 64) | |
| 2015–2016 | B/Massachusetts/02/2012 (lin. Yamagata) |
B/Phuket/3073/2013 (lin. Yamagata) |
B/Brisbane/60/2008c (lin. Victoria) |
125/236 | 4/4 | -151 (-1273; 54) | 1/10 | 69 (-160; 96) | 7/35 | 41 (-71; 79) | |
| Pooled analysis | 983/1300 | 20/25 | -54 (-200; 21) | 12/42 | 57 (12; 79) | 58/162 | 56 (36; 70) | ||||
VE: Vaccine Effectiveness; CI: Confidence Intervals; lin.: Lineage
a VE: adjusted VE by: age-groups (9–14; 15–44; 45–64; >64), sex, sentinel network and week of swabbing and season (pooled analysis).
b circulating strains antigenically matching the strain included in the current season vaccine
c circulating strains antigenically miss-matched with the strain included in the current season vaccine
d Similar to A/Victoria/361/2011