Identification of Neuraminidase Gene Mutations of Influenza A/H3N2 Isolates in Mazandaran Province, 2016-2018

Influenza is one of the viral infections of the respiratory system, which causes death in high-risk groups every year. The genomic changes of influenza virus make it susceptible to drug resistance, therefore, continuous monitoring of the influenza virus is highly important in order to recognize the efficacy of available drugs. The current study investigated the neuraminidase gene mutations of Influenza A/H3N2 in Mazandaran province between 2016 and 2018.

Twenty Influenza A/H3N2 samples of patients hospitalized in Mazandaran province were included in the study. PCR and electrophoresis tests were performed using primers designed for the region of the neuraminidase gene that contained the desired mutations. Then, the PCR product was sequenced to determine the mutations.

A total of 57 mutations were detected at the level of nucleotides, among which 19 were observed in all isolates, 13 were seen in most isolates, and 25 single mutations that were identified in some isolates. A total of 28 mutations were detected at the amino acid level, among which 13 mutations were observed in all isolates, 6 were detected in most isolates, and 9 single mutations seen in some isolates.

Although the sequence of the active site region is conserved in different subtypes of the neuraminidase gene, this region is still subject to mutation and genomic changes, which indicates changes in the active site region of the neuraminidase gene.