Open AccessInterim estimates of the effectiveness of the influenza vaccine against A(H3N2) influenza in adults in South Korea, 2016–2017 season
Author(s) -
Ji Yun Noh,
Sooyeon Lim,
Joon Young Song,
Won Suk Choi,
Hye Won Jeong,
Jung Yeon Heo,
Louis Jacob,
Yu Bin Seo,
Jin Soo Lee,
Seong Heon Wie,
Young Keun Kim,
Kyung Hwa Park,
Sook In Jung,
ShinWoo Kim,
Sun Hee Lee,
Han Sol Lee,
Young Hoon Yoon,
Hee Jin Cheong,
Woo Joo Kim
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0178010
Subject(s) - interim , vaccination , hemagglutinin (influenza) , confidence interval , influenza vaccine , seasonal influenza , virology , medicine , influenza a virus , influenza season , biology , virus , covid-19 , geography , infectious disease (medical specialty) , disease , archaeology
In the 2016–2017 season, the A(H3N2) influenza epidemic presented an unusual early peak pattern compared with past seasons in South Korea. The interim vaccine effectiveness (VE) of influenza vaccination in preventing laboratory-confirmed influenza was estimated using test-negative design through the tertiary hospital-based influenza surveillance system in South Korea. From 1 September, 2016 to 7 January, 2017, adjusted VE of influenza vaccination in preventing laboratory-confirmed A(H3N2) was -52.1% (95% confidence interval [CI], -147.2 to 6.4); -70.0% (95% CI, -212.0 to 7.4) in 19–64 years and 4.3% (95% CI, -137.8 to 61.5) in the elderly. Circulating A(H3N2) viruses belonged to the three phylogenetic subclades of 3C.2a, differently to A/Hong Kong/4801/2014, the current vaccine strain. Amino acid substitutions in hemagglutinin of circulating viruses seem to contribute to low VE. In conclusion, interim VE analysis presented that the protection of laboratory-confirmed influenza by seasonal influenza vaccination did not show the statistical significance in South Korea in the 2016–2017 influenza season.