Table 2.
Influenza Virus Vaccine Strain–Specific Hemagglutination-Inhibition (HI) Titers Among Children Vaccinated With 2010–2011 Trivalent Inactivated Influenza Vaccine, Overall and by Receipt of 2009–2010 Seasonal Influenza Vaccine
| Variable | A(H1N1) Strain, Titer
|
A(H3N2) Strain, Titer
|
B Strain, Titer
|
|||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A(H1N1)pdm09
|
A/Bris/59
|
A/Perth/16
|
A/Bris/10
|
B/Bris/60
|
B/Flor/4
|
|||||||||||||
| Overall | No Receipt |
Receipt | Overall | No Receipt |
Receipt | Overall | No Receipt |
Receipt | Overall | No Receipt |
Receipt | Overall | No Receipt |
Receipt | Overall | No Receipt |
Receipt | |
| Fold-rise > 4 | ||||||||||||||||||
|
| ||||||||||||||||||
| 28 d | 86.0 | … | … | 4.0 | … | … | 70.0 | … | … | 68.0 | … | … | 64.0 | … | … | 30.0 | … | … |
|
| ||||||||||||||||||
| HI > 40 | ||||||||||||||||||
|
| ||||||||||||||||||
| 0 d | 68.0 | 66.7 | 68.4 | 42.0 | 13.3a | 84.2 | 30.0 | 6.7a | 63.2 | 64.0 | 40.0a | 100.0 | 50.0 | 30.0a | 78.9 | 60.0 | 53.3 | 68.4 |
|
| ||||||||||||||||||
| 28 d | 96.0 | 96.7 | 94.7 | 44.0 | 20.0a | 78.9 | 84.0 | 76.7 | 94.7 | 94.0 | 90.0 | 100.0 | 96.0 | 100.0 | 89.5 | 80.0 | 83.3 | 73.7 |
|
| ||||||||||||||||||
| 7 mo | 95.9 | 96.7 | 94.4 | 38.8 | 16.7a | 72.2 | 73.5 | 70.0 | 77.8 | 85.7 | 80.0 | 94.4 | 91.8 | 93.3 | 88.9 | 63.3 | 63.3 | 61.1 |
|
| ||||||||||||||||||
| HI > 80 | ||||||||||||||||||
|
| ||||||||||||||||||
| 0 d | 36.0 | 30.0 | 47.7 | 26.0 | 6.7a | 52.6 | 22.0 | 3.3a | 47.4 | 50.0 | 20.0a | 94.7 | 36.0 | 20.0b | 57.9 | 42.0 | 30.0 | 57.9 |
|
| ||||||||||||||||||
| 28 d | 92.0 | 93.3 | 89.5 | 30.0 | 13.3b | 52.6 | 74.0 | 66.7 | 84.2 | 90.0 | 83.3 | 100.0 | 88.0 | 90.0 | 84.2 | 70.0 | 73.3 | 63.2 |
|
| ||||||||||||||||||
| 7 mo | 87.8 | 83.3 | 94.4 | 22.4 | 6.7b | 44.4 | 55.1 | 56.7 | 50.0 | 83.7 | 76.7 | 94.4 | 77.6 | 80.0 | 72.2 | 51.0 | 50.0 | 50.0 |
|
| ||||||||||||||||||
| HI > 160 | ||||||||||||||||||
|
| ||||||||||||||||||
| 0 d | 14.0 | 13.3 | 15.8 | 16.0 | 6.7 | 26.3 | 14.0 | 3.3c | 31.6 | 38.0 | 10.0a | 78.9 | 18.0 | 16.7 | 21.1 | 28.0 | 20.0 | 42.1 |
|
| ||||||||||||||||||
| 28 d | 86.0 | 86.7 | 84.2 | 16.0 | 6.7 | 26.3 | 66.0 | 56.7 | 78.9 | 84.0 | 76.7 | 94.7 | 70.0 | 73.3 | 63.2 | 52.0 | 53.3 | 52.6 |
|
| ||||||||||||||||||
| 7 mo | 67.3 | 66.7 | 66.7 | 14.3 | 6.7 | 22.2 | 40.8 | 33.3 | 50.0 | 67.3 | 63.3 | 72.2 | 38.8 | 43.3 | 27.8 | 36.7 | 36.7 | 38.9 |
The influence of prior seasonal vaccination on the percentage of subjects with HI titers of ≥ 40, 80, and 160 were assessed using the Fisher exact test for each virus strain. 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09), A/Perth/16, and B/Bris/60 were included in the 2010–2011 TIV; A/Bris/59, A/Bris10, and B/Bris/60 were included in the 2009–2010 TIV; and B/Flor/4 was included in the 2008–2009 TIV.
Significance is indicated by
P ≤ .001 vs recipients of TIV containing the specified strain.
P ≤ .01 vs recipients of TIV containing the specified strain.
P ≤ .05 vs recipients of TIV containing the specified strain.