山东省2017—2018年B型流感病毒药物敏感性检测及神经氨酸酶基因特征分析

Susceptibility to neuraminidase inhibitors and genetic characteristic of neuraminidase of influenza B viruses in Shandong Province during 2017 to 2018

目的检测山东省2017-2018流感监测年度B型流感病毒对神经氨酸酶抑制剂的药物敏感性,分析其神经氨酸酶(NA)基因特征。方法选取山东省2017—2018年分离的18株B型流感病毒(Yamagata系16株,Victoria系2株),通过生物学耐药实验检测病毒对奥司他韦和扎那米韦的药物敏感性。提取病毒核酸后一步法RT-PCR扩增NA基因片段,双向测定核苷酸序列,对基因序列和氨基酸序列特征比对分析。结果在检测的18株B型流感病毒中,有1株Yamagata系病毒对奥司他韦和扎那米韦2种药物的敏感性均降低,此株病毒的NA基因发生H274Y位点突变。其余15株Yamagata系病毒和2株Victoria系病毒均为奥司他韦及扎那米韦的敏感株。结论随机选取的18株B型流感病毒中大多数病毒对神经氨酸酶抑制剂敏感,临床上可继续使用此类药物对流感患者进行治疗。应加强耐药性监测,警惕耐药株的出现。

To investigate the susceptibility of influenza B viruses to neuraminidase inhibitors,and analyze the molecular characteristics of neuraminidase(NA)genes in Shandong province during 2017-2018 influenza surveillance year.18 strains of influenza B viruses(Yamagata-lineage:16,Victoria-lineage:2)isolated in Shandong province during 2017-2018 were selected to test the susceptibility to oseltamivir and zanamivir,with biological resistance experiments.After viral nucleotide was extracted,NA genes were amplified by one-step RT-PCR and then sequenced from both directions.The nucleotide and amino acid sequences were analyzed.Of all 18 influenza B viruses tested,1 Yamagata-lineage virus showed reduced sensitivity to both oseltamivir and zanamivir with NA gene possessing H274 Y amino acid mutation.Other 15 Yamagata-lineage viruses and 2 Victoria-lineage viruses were sensitive to oseltamivir and zanamivir.The majority of the 18 strains of influenza B viruses selected at random were sensitive to NAIs,which indicated that NAIs could be used continually for clinical treatment of patients with influenza.Sustained monitoring of antiviral susceptibility should be emphasized for timely detection of antiviral resistant viruses.