|
Strain
|
Previous vaccination†
|
Timepoint
|
SPR
|
SCR
|
MGI
|
|---|
|
n/N (%; 95% CI)
|
n/N (%; 95% CI)
|
N; value (95% CI)
|
|---|
|
18–60 years
|
>60 years
|
18–60 years
|
>60 years
|
18–60 years
|
>60 years
|
|---|
|
N = 28
|
N = 28
|
N = 28
|
N = 28
|
N = 28
|
N = 28
|
|---|
|
A/H1N1
|
Yes
|
Day 0
|
25/28
|
16/28
|
–
|
–
|
–
|
–
|
|
(89.3; 71.8–97.7)
|
(57.1; 37.2–75.5)
|
| | |
Day 21
|
28/28
|
25/28
|
10/28
|
9/28
|
28; 3.1
|
28; 3.5
|
|
(100; 87.7–100)
|
(89.3; 71.8–97.7)
|
(35.7; 18.6–55.9)
|
(32.1; 15.9–52.4)
|
(2.0–4.9)
|
(2.3–5.2)
|
| |
No
|
Day 0
|
19/28
|
10/28
|
–
|
–
|
–
|
–
|
|
(67.9; 47.6–84.1)
|
(35.7; 18.6–55.9)
|
| | |
Day 21
|
27/28
|
27/28
|
18/28
|
25/28
|
28; 7.4
|
28; 22.9
|
|
(96.4; 81.7–99.9)
|
(96.4; 81.7–99.9)
|
(64.3; 44.1–81.4)
|
(89.3; 71.8–97.7)
|
(4.1–13.3)
|
(12.7–41.2)
|
|
A/H3N2
|
Yes
|
Day 0
|
21/28
|
19/28
|
–
|
–
|
–
|
–
|
|
(75.0; 55.1–89.3)
|
(67.9; 47.6–84.1)
|
| | |
Day 21
|
27/28
|
26/28
|
9/28
|
13/28
|
28; 2.7
|
28; 3.4
|
|
(96.4; 81.7–99.9)
|
(92.9; 76.5–99.1)
|
(32.1; 15.9–52.4)
|
(46.4; 27.5–66.1)
|
(2.0–3.6)
|
(2.5–4.7)
|
| |
No
|
Day 0
|
13/28
|
9/28
|
–
|
–
|
–
|
–
|
|
(46.4; 27.5–66.1)
|
(32.1; 15.9–52.4)
|
| | |
Day 21
|
27/28
|
27/28
|
18/28
|
22/28
|
28; 8.5
|
28; 13.8
|
|
(96.4; 81.7–99.9)
|
(96.4; 81.7–99.9)
|
(64.3; 44.1–81.4)
|
(78.6; 59.0–91.7
|
(5.2–13.9)
|
(7.4–25.6)
|
|
B strain (Victoria)
|
Yes
|
Day 0
|
26/28
|
17/28
|
–
|
–
|
–
|
–
|
|
(92.9; 76.5–99.1)
|
(60.7; 40.6–78.5)
|
| | |
Day 21
|
28/28
|
27/28
|
4/28
|
12/28
|
28; 2.4
|
28; 3.3
|
|
(100; 87.7–100)
|
(96.4; 81.7–99.9)
|
(14.3; 4.0–32.7)
|
(42.9; 24.5–62.8)
|
(1.7–3.3)
|
(2.3–4.9)
|
| |
No
|
Day 0
|
21/28
|
14/28
|
–
|
–
|
–
|
–
|
|
(75.0; 55.1–89.3)
|
(50.0; 30.6–69.4)
|
| | |
Day 21
|
28/28
|
28/28
|
15/28
|
21/28
|
28; 4.9
|
28; 11.5
|
|
(100; 87.7–100)
|
(100; 87.7–100)
|
(53.6; 33.9–72.5)
|
(75.0; 55.1–89.3)
|
(3.0–7.9)
|
(6.8–19.2)
|
|
B strain (Yamagata)
|
Yes
|
Day 0
|
27/28
|
24/28
|
–
|
–
|
–
|
–
|
|
(96.4; 81.7–99.9)
|
(85.7; 67.3–96.0)
|
| | |
Day 21
|
28/28
|
28/28
|
6/28
|
12/28
|
28; 2.1
|
28; 4.1
|
|
(100; 87.7–100)
|
(100; 87.7–100)
|
(21.4; 8.3–41.0)
|
(42.9; 24.5–62.8)
|
(1.6–2.7)
|
(2.6–6.5)
|
| |
No
|
Day 0
|
21/28
|
21/28
|
–
|
–
|
–
|
–
|
|
(75.0; 55.1–89.3)
|
(75.0; 55.1–89.3)
|
| | |
Day 21
|
28/28
|
28/28
|
14/28
|
23/28
|
28; 4.6
|
28; 9.4
|
|
(100; 87.7–100)
|
(100; 87.7–100)
|
(50.0; 30.6–69.4)
|
(82.1; 63.1–93.9)
|
(3.1–6.9)
|
(6.4–13.8)
|
- †Received (yes) or did not receive (no) seasonal influenza vaccine during the preceding season (2010–2011); QIV, inactivated quadrivalent influenza vaccine; n/N, number fulfilling definition of response/total number in group; SCR, seroconversion rate defined as the proportion with antibody titer <1:10 at baseline and with post-vaccination titer of ≥1:40, or pre-vaccination titer of ≥1:10 and a ≥4-fold post-vaccination increase in titer; SPR, seroprotection rate defined as proportion with post-vaccination titer ≥1:40; MGI, mean geometric increase defined as the geometric mean of the ratio between pre-vaccination and post-vaccination reciprocal titers; Immune responses were assessed according to the to the European Union Committee for Medicinal Products for Human Use (CHMP) licensure criteria: to fulfil the criteria the point estimates for SCR needed to be >40%, for SPR >70%, and MGI >2.5 in the 18–60 years group, and SCR >30%, for SPR >60%, and MGI >2.0 in the >60 years group [21].
