河南省急性呼吸道感染病例人副流感病毒3型血凝素-神经氨酸酶基因特征分析

Characteristics of hemagglutinin-neuraminidase gene of human parainfluenza virus type 3 among patients with acute respiratory tract infection in Henan Province

目的了解河南省急性呼吸道感染(ARI)病例中人副流感病毒3型(HPIV3)血凝素-神经氨酸酶(HN)的基因特征。方法对河南省漯河市采集的严重急性呼吸道感染(SARI)病例标本和郑州市采集的流感样病例(ILI)标本进行人副流感病毒(HPIVs)核酸检测, HPIV3检测阳性标本使用RT-PCR法进行HN基因扩增并测序, 使用CExpress以及MEGA7.0软件进行序列编辑、进化树构建和基因特征分析。结果漯河市和郑州市共采集ARI咽拭子标本374份, 其中HPIV3核酸检测阳性标本20份(5.3%), 对阳性标本进行靶基因扩增后获得18条序列, 经分析全部为C3亚群, 其中有16条序列为C3f基因型, 有2条序列为C3a基因型。18株HPIV3的HN基因序列的核苷酸和氨基酸同源性分别为97.6%~100.0%和99.3%~100.0%, 与原株型Wash/47885/57相比差异较大, 发生了12处共同的氨基酸突变, 其中H295Y、I391V、D556N和I53T是功能相关突变位点。与流行株China/BCH4210A/2014相比同源性较高, 未发生共同的氨基酸突变, 未发现新的功能相关突变位点。结论河南省近年流行的HPIV3为C3亚型的C3f和C3a分支, 可能建立了本土循环流行。应对HPIV3的C3亚型进行持续深入的监测, 为防控HPIV3相关疾病提供科学依据。

Objective To analyze the molecular characteristics of hemagglutinin-neuraminidase(HN)gene of human parainfluenza virus type 3(HPIV3)among the cases with acute respiratory tract infection(ARI)in Henan Province.Methods Nasal/throat swab samples collected from patients with severe acute respiratory tract infection(SARI)in Luohe and patients with influenza-like illness(ILI)in Zhengzhou were used in this study.HPIV nucleic acids in the samples were detected using real-time fluorescent PCR.HPIV3-positive samples were subjected to RT-PCR for the amplification of HN genes and the sequences were analyzed with Sanger method.CExpress and MEGA7.0 software were used for sequences editing,evolution tree construction and gene sequence analysis.Results A total of 374 throat swab samples collected form ARI cases in Luohe and Zhengzhou were tested and 20(5.3%)of them were positive for HPIV3.Eighteen HPIV3 HN gene sequences were successfully amplified and all belonged to C3 subgroups,including 16 sequences of C3f genotype and two sequences of C3a genotype.The 18 HN gene sequences shared the homology of 97.6%-100.0%in nucleotide and 99.3%-100.0%in amino acid,but the differences between them and the prototype strain Wash/47885/57 were significant.There were 12 amino acid mutations shared by them,including four function-related mutations(H295Y,I391V,D556N and I53T).There were no significant differences in the nucleotide or amino acid sequences as compared with the epidemic strain of China/BCH4210A/2014.Conclusions The C3f and C3a branches of HPIV3 were the epidemic genotypes in Henan Province in recent years and a local circulating prevalence might be established.Continuous and in-depth monitoring of HPIV3 C3 subtype would be of great significance for the prevention and control of HPIV3-associated diseases.