Drug resistance analysis of influenza virus to neuraminidase inhibitor from 2018 to 2019 in Hebei Province / 中华疾病控制杂志

ABSTRACT

Objective To analyze the resistance of influenza virus to neuraminidase inhibitors (NAI) in Hebei province during 2018-2019. Methods Virus were collected from the Hebei Influenza Surveillance Network during 2018-2019. A total of 36 confirmed influenza viruses (with 25 H1pdm09 and 11 H3N2) were selected to test resistance to oseltamivir and zanamivi with fluorescence (FL). Results All 36 influenza viruses tested were sensitive to oseltamivir and zanamivir. The median half maximal inhibitory concentration (IC50) for oseltamivir of H1pdm09 and H3N2 were of 0.50 nM (range 0.07-1.14 nM) and 0.25 nM (range 0.09-0.69 nM) respectively, while 0.29 nM (range 0.09-0.85 nM) and 0.87(range 0.17-1.81 nM) for zanamivir, all were within 10 fold IC50 of the reference virus (corresponding type). Conclusion All the tested influenza strains isolated in Hebei province during 2018-2019 were sensitive to NAI.