TY - JOUR
T1 - Trivalent inactivated influenza vaccine effective against influenza a(H3n2) variant viruses in children during the 2014/15 season, Japan
AU - Sugaya, Norio
AU - Shinjoh, M.
AU - Kawakami, C.
AU - Yamaguchi, Y.
AU - Yoshida, M.
AU - Baba, H.
AU - Ishikawa, M.
AU - Kono, M.
AU - Sekiguchi, S.
AU - Kimiya, T.
AU - Mitamura, K.
AU - Fujino, M.
AU - Komiyama, O.
AU - Yoshida, N.
AU - Tsunematsu, K.
AU - Narabayashi, A.
AU - Nakata, Y.
AU - Sato, A.
AU - Taguchi, N.
AU - Fujita, H.
AU - Toki, M.
AU - Myokai, M.
AU - Ookawara, I.
AU - Takahashi, T.
N1 - Publisher Copyright:
© 2016, Emanuel University Press. All rights reserved.
PY - 2016/10/20
Y1 - 2016/10/20
N2 - The 2014/15 influenza season in Japan was characterised by predominant influenza A(H3N2) activity; 99% of influenza A viruses detected were A(H3N2). Subclade 3C.2a viruses were the major epidemic A(H3N2) viruses, and were genetically distinct from A/New York/39/2012(H3N2) of 2014/15 vaccine strain in Japan, which was classified as clade 3C.1. We assessed vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) in children aged 6 months to 15 years by test-negative case–control design based on influenza rapid diagnostic test. Between November 2014 and March 2015, a total of 3,752 children were enrolled: 1,633 tested positive for influenza A and 42 for influenza B, and 2,077 tested negative. Adjusted VE was 38% (95% confidence intervals (CI): 28 to 46) against influenza virus infection overall, 37% (95% CI: 27 to 45) against influenza A, and 47% (95% CI: -2 to 73) against influenza B. However, IIV was not statistically significantly effective against influenza A in infants aged 6 to 11 months or adolescents aged 13 to 15 years. VE in preventing hospitalisation for influenza A infection was 55% (95% CI: 42 to 64). Trivalent IIV that included A/New York/39/2012(H3N2) was effective against drifted influenza A(H3N2) virus, although vaccine mismatch resulted in low VE.
AB - The 2014/15 influenza season in Japan was characterised by predominant influenza A(H3N2) activity; 99% of influenza A viruses detected were A(H3N2). Subclade 3C.2a viruses were the major epidemic A(H3N2) viruses, and were genetically distinct from A/New York/39/2012(H3N2) of 2014/15 vaccine strain in Japan, which was classified as clade 3C.1. We assessed vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) in children aged 6 months to 15 years by test-negative case–control design based on influenza rapid diagnostic test. Between November 2014 and March 2015, a total of 3,752 children were enrolled: 1,633 tested positive for influenza A and 42 for influenza B, and 2,077 tested negative. Adjusted VE was 38% (95% confidence intervals (CI): 28 to 46) against influenza virus infection overall, 37% (95% CI: 27 to 45) against influenza A, and 47% (95% CI: -2 to 73) against influenza B. However, IIV was not statistically significantly effective against influenza A in infants aged 6 to 11 months or adolescents aged 13 to 15 years. VE in preventing hospitalisation for influenza A infection was 55% (95% CI: 42 to 64). Trivalent IIV that included A/New York/39/2012(H3N2) was effective against drifted influenza A(H3N2) virus, although vaccine mismatch resulted in low VE.
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U2 - 10.2807/1560-7917.ES.2016.21.42.30377
DO - 10.2807/1560-7917.ES.2016.21.42.30377
M3 - Article
C2 - 27784529
AN - SCOPUS:85013758876
SN - 1025-496X
VL - 21
JO - Eurosurveillance
JF - Eurosurveillance
IS - 42
ER -