Genetic characterization of influenza A virus and assessment of vaccine efficacy in Yantai from 2014 to 2017
10.3760/cma.j.issn.0253-9624.2019.08.008
- VernacularTitle: 2014—2017年烟台市甲型流感HA基因变异及疫苗效果分析
- Author:
Juan LIU
1
;
Yingchun XU
;
Zhenlu SUN
;
Qiao GAO
;
Zhaojing DONG
;
Xiaowen XU
;
Lianfeng GONG
Author Information
1. Microbiology laboratory Yantai Center for Disease Prevention and Control, Yantai 264003, China
- Publication Type:Journal Article
- Keywords:
Influenza A virus;
Hemagglutinins, viral;
Antigenic variation;
Vaccine efficacy;
Survalleince
- From:
Chinese Journal of Preventive Medicine
2019;53(8):840-842
- CountryChina
- Language:Chinese
-
Abstract:
In this study, the swabs were collected among patients with an influenza-like illness (ILI) admitted to 2 sentinel surveillance hospitals of Yantai from April 2014 to August 2017. All specimen were cultured and identified by hemagglutination inhibition assay. Complete sequences of Hemagglutinin (HA) of influenza A were amplified, sequenced and analyzed using molecular and phylogenetic methods. The potential vaccine efficacy were calculated using Pepitope model. The results showed that the antigenicity of A (H3N2) had changed greatly. 8 strains of influenza A (H1N1) pdm09 belonged to subclade 6B.1 and 14 strains clustered in 6B.2. 12 strains of influenza A (H3N2) fell into subgroup 3C.3a and 33 strains clustered in 3C.2a. Several residues at antigen sites and potential glycosylation sites had changed in influenza A strains. Vaccine efficacy of influenza A (H1N1) pdm09 in 2015/2016 and 2016/2017 seasons were 77.29% and 79.11% of that of a perfect match with vaccine strain, meanwhile vaccine efficacy of influenza A (H3N2) in 2014/2015, 2015/2016 and 2016/2017 were-5.18%, 16.97% and 42.05% separately. In conclusion, the influenza A virus circulated in Yantai from 2014 to 2017 presented continual genetic variation. The recommended vaccine strains still afforded protection against influenza A (H1N1) pdm09 strains and provided suboptimal protection against influenza A (H3N2) strains.
