Molecular characteristics of neuraminidase and drug resistance analysis of influenza virus epidemic strains in Anhui Province from 2021 to 2024
- Author:
YU Junling
;
SUN Yong
;
HE Jun
- Publication Type:Journal Article
- Keywords:
Influenza virus;
neuraminidase;
drug resistance;
molecular characteristic;
Anhui
- From:
China Tropical Medicine
2024;24(12):1445-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the drug resistance of influenza virus strains in Anhui Province from 2021 to 2024 and analyze the mutation and molecular evolution characteristics of the neuraminidase (NA) for providing a reference for influenza prevention and clinical drug use in Anhui Province. Methods Throat swab samples from influenza-like cases in Anhui Province from 2021 to 2024 were collected for nucleic acid detection and virus isolation. A total of 70 randomly selected influenza virus epidemic strains were subjected to neuraminidase inhibitor (NAI) sensitivity testing using an NA activity inhibition assay. The molecular evolution characteristics of the virus NA gene were analyzed using viral genome sequencing and molecular biology software. Results Among the 70 epidemic strains, only one H1N1pdm subtype influenza virus showed decreased sensitivity to Zanamivir (IC50=1.252 nmol/L), while the other epidemic strains were sensitive to both Oseltamivir and Zanamivir, with no strains demonstrating highly reduced sensitivity to NAI. Amino acid sequence analysis revealed no mutations in key amino acid sites in the NA catalytic active region. However, there were significant differences in IC50 of different types of influenza viruses against different drugs. The NA gene genetic phylogenetic tree showed that 20 influenza B viruses and the vaccine strains were classified into Clade A.1 branch, while among the 40 influenza A viruses (H3N2 subtype), only one epidemic strain differed from the vaccine strain and was clustered into Clade A.2, while the remaining 39 strains shared Clade B with the vaccine strain. only one epidemic strain (H3N2 subtype) was different from the vaccine strains and clustered into the Clade A.2 branch, with the remaining 39 strains shared the Clade B branch with the vaccine strain. Conclusions In Anhui Province from 2021 to 2024, 98.6% (69/70) of the influenza virus epidemic strains remained sensitive to NAI drugs, but there is a risk of continued mutation in the virus NA gene. With the widespread use of drugs, the surveillance of influenza virus resistance should be continuously strengthened to better guide the prevention of infectious diseases and clinical medication.
- Full text:20251113150736287533.Molecular characteristics of neuraminidase and drug resistance analysis of influenza virus epidemic strains in Anhui Province from 2021 to 2024.pdf
