Molecular epidemiological analysis of Influenza viruses in
Influenza-like illness cases: a retrospective study in Chongqing Hi-Tech
Zone, China (2021-2024)
Abstract
To analyze the molecular epidemiological characteristics of influenza
viruses in influenza-like cases in Chongqing Hi-Tech Zone, China, to
provide data support and a scientific basis for optimizing influenza
prevention and control strategies in the region. A retrospective
analysis was conducted on the molecular epidemiological characteristics
of influenza viruses in influenza-like cases at a hospital in Chongqing
Hi-Tech Zone from 2021 to 2024. Colloidal gold detection of viral
antibodies, fluorescent PCR detection of nucleic acids, and gene
sequencing were used to identify the different subtypes. Among 39,986
ILI specimens tested using the immunocolloid gold method, 6,616
influenza viruses were detected, with a detection rate of 16.54%.
Infections included 4,464 influenza A viruses (67.50%), 2,033 influenza
B viruses (30.73%), and 119 co-infections of influenza A and B viruses
(1.77%).In this region, H3N2 was the predominant subtype of influenza
A, and Victoria was the main subtype of influenza B. Influenza epidemics
in the winter and spring seasons in Chongqing Hi-Tech Zone were
predominantly caused by influenza A, with influenza B also circulating.
Influenza A strains were mainly H3N2, while influenza B strains were
primarily Victoria.