Genomic characterization of seven reassortant influenza B viruses in Hangzhou, China
10.3760/cma.j.cn112309-20221201-00395
- VernacularTitle:杭州地区7株重排乙型流感病毒基因组特征分析
- Author:
Pan ZHAO
1
;
Gang ZHAO
;
Zan NI
;
Xinfen YU
;
Xiaofeng QIU
;
Yinyan ZHOU
;
Jun LI
Author Information
1. 杭州市疾病预防控制中心卫生检验中心，杭州 310021
- Keywords:
Influenza B virus;
Whole genome;
Reassortant;
Genetic evolution;
Neuraminidase
- From:
Chinese Journal of Microbiology and Immunology
2023;43(5):341-350
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the prevalence of influenza B virus in Hangzhou from 2014 to 2020 and the genetic evolution of seven reassortant strains of influenza B virus.Methods:Influenza viruses were isolated from throat swabs collected from 16 943 patients with influenza-like illness in Hangzhou from January 2014 to December 2020. The subtypes of influenza viruses were identified by real-time RT-PCR. Eight genes ( PB2, PB1, PA, HA, NP, NA, MP and NS) of influenza B viruses were amplified with specific primers and then analyzed with nanopore sequencing and phylogenetic analysis. Results:From January 2014 to December 2020, there were 1 090 influenza B virus-positive samples, including 474 samples of Yamagata lineage and 616 samples of Victoria lineage, were identified in Hangzhou with an overall positive rate of 6.43% (1 090/16 943). Whole genomes of 228 strains of influenza B virus were obtained by nanopore sequencing and seven reassortant strains of influenza B virus were found. There were four reassortant influenza B viruses of Yamagata lineage with NA gene fragments from viruses of Victoria lineage, two strains of Yamagata lineage (H644_BY and H648_BY) with NP and NA gene fragments from Victoria lineage and one strain of Victoria lineage with PB2, PB1, PA and NS gene fragments from Yamagata lineage. Meanwhile, these seven strains possessed several mutations in the antigenic sites of HA and NA genes. Conclusions:Several rare reassortant strains of influenza B virus with epidemic potential were detected in Hangzhou from 2014 to 2020, which indicated that the traditional detection methods should be improved and more attention should be paid to the reassortant influenza B viruses and the match between epidemic and vaccine strains.
