目的 分析福建省泉州市2023年甲型H1N1流感病毒的血凝素(HA)、神经氨酸酶(NA)基因进化及变异特征,为流感防控提供数据支撑。方法 采用实时荧光定量PCR对2023年泉州市流感监测标本进行核酸检测,核酸阳性标本再经过MDCK细胞培养、鉴定、分型,选取甲型H1N1流感病毒阳性毒株进行高通量三代测序,通过高效反转录、全基因组扩增进行核酸捕获,采用连接法测序多样本DNA建库上机测序获得18株甲型H1N1流感病毒的HA基因和NA基因序列,并从NCBI病毒库中下载37株病毒基因序列,采用Mega软件构建进化树进行变异分析。结果 18株甲型HIN1流感病毒毒株中11株位于同一进化分支,与疫苗株A/Victoria/4897/2022亲缘关系较近,其余7株病毒分别位于3个分支,且与2023年中国其他地区分离出的甲型H1N1病毒遗传距离相近。18株甲型H1N1流感毒株与疫苗株A/Victoria/4897/2022相比,HA基因和NA基因编码区片段均发生核苷酸变异,HA基因主要突变包括Q54K、N130K、S137P、R142K、A216T、R223Q、E260N/D、A277T、D356S/E、V418I/S、H454N/T,NA基因主要突变包括D50N、K51Q、F66Y、S74F、K222N、E382G、K389I、I452T、M453V、N469K。结论 泉州市2023年甲型H1N1流感病毒HA、NA基因逐渐发生变异,应继续监测甲型H1N1流感病毒HA、NA基因的进化及变异情况,预防甲型H1N1流感大流行的发生。

Objective To analyze the evolution and variation characteristics of the Hemagglutinin (HA) and Neuraminidase (NA) genes of influenza A (H1N1) virus in Quanzhou City,Fujian Province in 2023,and to provide data support for influenza prevention and control. Methods Real-time fluorescence quantitative PCR was used to perform nucleic acid detection of influenza surveillance specimens in Quanzhou City in 2023.The nucleic acid-positive specimens were then cultured,identified,and typed by MDCK cells.The positive strains of influenza A (H1N1) virus were selected for high-throughput third-generation sequencing.Nucleic acid was captured by efficient reverse transcription and whole genome amplification.The ligation method was used to sequence multiple sample DNA libraries for on-machine sequencing to obtain the HA and NA gene sequences of 18 influenza A (H1N1) viruses.The gene sequences of 37 viruses were downloaded from the NCBI virus library,and the Mega software was used to construct evolutionary trees for variation analysis. Results Eleven of the 18 influenza A (H1N1) virus strains were located in the same evolutionary branch and were closely related to the vaccine strain A/Victoria/4897/2022.The remaining seven strains were located in three branches and were genetically close to the influenza A (H1N1) viruses isolated from other regions in China in 2023.Compared with the vaccine strain A/Victoria/4897/2022,the HA gene and NA gene coding region fragments of the 18 influenza A (H1N1) strains had nucleotide variations.The major mutations of the HA gene included Q54K, N130K, S137P, R142K, A216T, R223Q, E260N/D, A277T, D356S/E, V418I/S, H454N/T, and the major mutations of the NA gene include D50N, K51Q, F66Y, S74F, K222N, E382G, K389I, I452T, M453V, N469K. Conclusion The HA and NA genes of the influenza A (H1N1) virus are gradually mutating in Quanzhou City in 2023.It is necessary to continue to monitor the evolution and mutation of the HA and NA genes of the influenza A(H1N1) virus in order to prevent the occurrence of a pandemic.