Phylogenetic analysis of influenza B in the Yellow River Delta region,China,in 2021-2024
10.3969/j.issn.1002-2694.2025.00.047
- VernacularTitle:2021-2024年黄河三角洲地区乙型流感病毒基因进化特征分析
- Author:
Li-fang ZHANG
1
;
Na-na ZHAO
;
Xiu-sheng YIN
;
Yu-jie HE
;
Yuan LI
;
Ping LI
Author Information
1. 滨州市疾病预防控制中心,滨州市人兽共患病重点实验室,滨州 256600
- Publication Type:Journal Article
- Keywords:
B(Victoria)influenza virus;
whole genome sequence;
reassortment
- From:
Chinese Journal of Zoonoses
2025;41(3):249-254,262
- CountryChina
- Language:Chinese
-
Abstract:
This study analyzed the variations and evolution characteristics of influenza B Victoria(BV)virus in the Yellow River Delta region of China during 2021-2024.Throat swabs were collected from people with influenza-like illness(ILI)from 2021 to 2024 in Binzhou and Dongying,China.Viral isolation was performed,and 22 representative influenza BV isolates were selected for whole genome sequencing.Phylogenetic analysis of whole-genome sequences was performed in MegAlign and MEGA software.A total of 27 674 samples were obtained,and the overall positivity rate of influenza virus(A/H3N2,A/H1N1,BV)was 11.1％.Our surveillance data indicated that influenza B virus was detected in 2 years,which showed positivity rates of 28.2％and 1.7％,respectively.Statistically significant differences in the positivity rates of influenza BV viruses were observed(x2=3 641.791,P＜0.001).The median pairwise sequence identities ranged from 98.7％to 99.3％for eight segments of 22 viral sequences.The isolates for the monitoring years 2021-2024 were located in clades V1A.3a.1 and V1A.3a.2.Intra-lineage reassortments were discovered in B/shandongbincheng17/2022.The NA gene of one isolate exhibited an increase in the 488NLTV N-glycoproteome site.The K338R mutation occurred in the PA gene.Three locus deletion or insertion mutations occurred in the MP gene.The BV influenza epidemic was prevalent every other year;the intensity ranged from strong to weak;and the duration ranged from long to short in the Yellow River Delta region of China during 2021-2022.Influ-enza B virus formed intra-lineage reassortments,and showed significant mutations in NA gene,PA gene,and MP gene.
