Analyzed the Resistance of Influenza B Virus in Shangrao

Abstract

Influenza B is one of the main pathogens of human infection, especially among children and adolescents. The incidence rate and mortality rate are higher after infection. Vaccines and drugs are the most effective means to prevent and treat influenza virus. However, due to the characteristics of easy mutation of influenza virus, there are many drug-resistant strains in clinical using. In this study, we analyzed the molecular characterization of neuraminidase (NA) genes and NA drug resistance of influenza B virus in Shangrao during 2019 years. The specimens of nasopharyngeal swabs were collected from influenza cases of monitor hospitals, and then the collection of 10 strains of influenza B virus were randomly selected for detection by MDCK, positive strains were identified by hemagglutination test (HA) and hemagglutination inhibition test (HI). And virus RNA were extracted with QIAamp Viral RNA Mini Kit. Fragments of NA genes were amplified by one-step RT-PCR and then were sequenced. The data obtained were analyzed with the software DNAStar 6.0 and Mage 5.0. We observed that the nucleotides of NA gene of 10 strains had no mutation in catalytic residues and framework residues of NA gene. And strongly suggest that all viruses were sensitive to neuraminidase inhibitors, however continuous resistance surveillance is necessary for control and prevention influenza.