2017年云南省流感病毒监测及甲型H1N1流感病毒血凝素基因特征分析

目的 了解2017年云南省流感病毒的流行情况和甲型H1N1流感病毒的血凝素（HA）基因分子特征。方法 对2017年云南省流感监测哨点医院采集的21 672份标本使用real - time RT - PCR方法检测流感病毒，核酸阳性标本使用MDCK细胞进行病毒分离，采用血凝素凝集试验及抑制试验进行病毒抗原性分析。选取12株抗原性变异较大的甲型H1N1流感毒株进行基因测序，使用MEGA软件分析其HA基因特征。结果 2017年共检出流感核酸阳性标本2 372份，分离出流感毒株1 180株，全年共有2个流行高峰，H3亚型和甲型H1N1亚型交替成为优势株，BY亚型和BV亚型共同流行。毒株分离高峰与ILI%高峰基本一致。甲型H1N1流感病毒ＨＡ基因无明显变异，疫苗株仍具有保护作用。结论 继续加强监测力度，提高监测敏感性并做到及时预警，控制流感流行风险。

Epidemiological survey of influenza surveillance and analysis of hemagglutinin gene characteristics of influenza A H1N1 virus in Yunnan Province in 2017

Objective To understand the prevalence of influenza virus in Yunnan Province in 2017 and the molecular characteristics of hemagglutinin(HA) gene of influenza A(H1N1) virus. Methods The 21672 samples collected from the Influenza Surgery Hospital of Yunnan Province in 2017 were assayed by real-time RT-PCR. The nucleic acid-positive specimens were isolated by MDCK cells, and the hemagglutinin agglutination test and inhibition test were used for virus antigens. Twelve strains of influenza A H1N1 strain with large antigenic variation were selected for gene sequencing, and the HA gene characteristics were analyzed using MEGA software. Results A total of 2372 influenza-positive samples were detected in 2017, and 1180 strains of influenza strains were isolated. There were two epidemic peaks throughout the year. H3 subtypes and H1N1 subtypes alternated into dominant strains, with co-occurrence of BY subtype and BV subtype. The peak of virus isolation was basically consistent with the peak of ILI%. There is no obvious variation in the HA gene of influenza A H1N1 influenza virus, and the vaccine strain still has a protective effect. Conclusion It is essential to strengthen monitoring, improve monitoring sensitivity and timely manage warning to control the influenza epidemic risk.