2014年长沙市禽类场所环境H9N2亚型禽流感病毒分子流行特征分析

发布时间：2018-06-25 13:52

本文选题：禽类场所 + 环境　；参考：《中国人兽共患病学报》2017年03期

【摘要】：目的了解2014年长沙市禽类场所环境中H9N2亚型禽流感病毒(Avian influenza virus,AIV)血凝素(Hemagglutinin,HA)、神经氨酸酶(Neuraminidase,NA)和非结构蛋白(ron-structural,NS)基因的分子进化特征,为人感染H9N2亚型AIV防控提供实验室科学证据支持。方法对2014年长沙市禽类场所中采集的501份环境标本(禽类饮水263份,污水221份,其他标本17份)利用real-time PCR方法进行A型、H5、H7和H9亚型流感病毒核酸检测,然后对单独H9阳性标本利用HA和NA基因通用引物进行RT-PCR扩增和核苷酸测序,病毒HA、NA及NS基因测序结果在线BLAST分析,利用Bioedit和Mega5软件进行氨基酸比对和进化树构建。结果从501份环境标本中检出A型AIV核酸阳性标本350份,H9亚型核酸阳性标本191份,占总标本数量的38.12%,H5亚型核酸阳性标本177份(35.33%),H7亚型核酸阳性11份(2.20%),H5和H9亚型混合核酸阳性标本68份(13.57%)。部分单独H9亚型核酸阳性标本经RT-PCR和核苷酸测序鉴定出阳性H9N2亚型病毒核酸标本23份,分子进化分析表明2014年长沙市禽类场所环境中的绝大部分H9N2亚型AIV HA、NA、NS基因来源于A/Chicken/Shanghai/F/98(F98)类似株病毒,属于新的S基因型,HA蛋白受体结合位点(Receptor binding site,RBS)第235位(对应H3流感第226位)氨基酸为Leu(L),表现为特异性结合人流感病毒受体特征,病毒HA、NA及NS蛋白关键分子位点表现为低致病性的分子特征。结论 2014年长沙市禽类场所环境中H9亚型AIV核酸阳性率最高,H9N2亚型AIV的HA、NA和NS基因表现为低致病性的分子特征,但具有容易感染人类的特征,需要进一步加强监测。
[Abstract]:Objective to investigate the molecular evolutionary characteristics of hemagglutinin (HA), neuraminidase (na) and nonstructural protein (ron-structuralNS) genes of H9N2 subtype avian influenza virus (Avian influenza virusus AIV) in poultry environment of Changsha City in 2014, and to provide scientific evidence for the prevention and control of human infection with H9N2 subtype AIV. Methods 501 environmental specimens collected from poultry sites in Changsha City in 2014 (263 birds drinking water, 221 sewage samples and 17 other specimens) were detected by real-time polymerase chain reaction (real-time) for influenza virus type A H5H7 and H9 subtype influenza virus nucleic acid. Then the H9 positive samples were amplified by RT-PCR and nucleotide sequencing using HA and na gene universal primers. The results of Hana and NS gene sequencing were analyzed online by blast. The amino acid alignment and phylogenetic tree were constructed by Bioedit and Mega5 software. Results out of 501 environmental samples, 350 AIV positive samples were found to be positive for H9 subtype nucleic acid, 191 samples were positive for H9 subtype nucleic acid. Of the total samples, 177 (35.33%) were positive for nucleic acid of H5 subtype and 68 (13.57%) were mixed nucleic acid positive for H5 and H9 subtypes in 11 (2.20%) of H7 subtype nucleic acid positive specimens. A total of 23 H9N2 subtype nucleic acid samples were identified by RT-PCR and nucleotide sequencing. Molecular evolution analysis showed that most of the H9N2 subtype AIV HNANAN NS gene in the poultry environment of Changsha City in 2014 was derived from a similar strain of A / Chickenr / Shanghai / F / 98 (F98) virus. Leu (L) is the amino acid at the 235th position (corresponding to the 226th position of H3 influenza) in the receptor binding site of the new S genotype of the HA protein, which exhibits the characteristic of specific binding to human influenza virus receptor. The key molecular loci of HAN na and NS protein were characterized by low pathogenicity. Conclusion the H9 subtype AIV nucleic acid positive rate in the poultry environment of Changsha City in 2014 is the highest, the H9N2 subtype AIV gene shows the low pathogenicity molecular characteristic, but has the characteristic of easy to infect the human, needs to strengthen the surveillance.
【作者单位】：长沙市疾病预防控制中心;
【基金】：湖南省卫生计生委2015年度科研计划项目(No.B2015-153)~~
【分类号】：R511.7

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