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1.
2013年8月某养马厂出现疑似马流感疫情,经分离鉴定为H3N8亚型马流感病毒。为了了解该H3N8马流感分离株(A/equine/Xuzhou/01/2013(H3N8))的基因进化情况,本试验比较了该病毒株,我国已报道的H3N8马流感毒株以及目前全球所使用的疫苗株的病毒基因型,也比较了与抗原性相关的氨基酸的变化情况,为科学防控马流感提供参考依据。采集病死马的内脏样本,进行了A型禽流感病毒通用荧光RT-PCR检测,将荧光RT-PCR检测阳性样品处理后接种鸡胚尿囊腔,检测分离毒尿囊液血凝性及HA效价。参照已发表的扩增H3N8马流感病毒全基因引物,经RT-PCR扩增出该H3N8亚型马流感病毒(A/equine/Xuzhou/01/2013(H3N8))的8个基因片段,对其测序构建基因进化树,并进行分子特征分析。经过比较分析,该病毒株的HA基因在遗传进化上属于佛罗里达Ⅱ型马流感病毒,其余7个片段都属于马流感病毒中的美洲型。在5个公认的抗原位点中,A/equine/Xuzhou/01/2013与我国2007年的分离株(A/donkey/Xinjiang/2007),目前的疫苗株(Miami/63,Kentucky/81,Suffolk/89,Newmarket/2/93和Avesta/93)相比均发生了一些位点的变异。我国H3N8亚型马流感病毒存在抗原变异,需要进一步对其致病性、免疫原性等特性进行研究,同时还需加强马流感病毒分子流行病学监测。  相似文献   

2.
马流感A/马/京防/74-1(H7N7)毒株HA基因的序列分析   总被引:6,自引:0,他引:6  
流感病毒(Influenza Virus)根据血凝素(HA)和神经氨酸酶(NA)两种表面抗原蛋白分为不同的亚型,马流感I型(H7N7)和Ⅱ型(H3N8)是其中比较重要的两个亚型.本研究应用无特定病原体(SPF)鸡胚增殖马流感病毒A/马/京防/74-1(H7N7)毒株,TRIzol LS Reagent提取病毒RNA,RT-PCR扩增HA基因全片段,克隆到PMD18-T载体上,并进行了鉴定和序列测定.所获得的HA基因片段长1 727 bp,编码563个氨基酸残基.根据推导的氨基酸序列进行预测,有7个潜在的糖基化位点和16个半胱氨酸残基,通过序列分析推断,A/马/京防/74-1(H7N7)株病毒的HA来源于禽类,是一株通过基因重排出现的重组病毒.  相似文献   

3.
对具有流感临床症状的病马组织经处理后接种SPF鸡胚,分离到1株流感病毒。该病毒经鸡胚接种7代后,出现稳定的对鸡红细胞凝集效价,效价为25,能被H3亚型血清中和,与H1、H5、H7、H9亚型阳性血清无交叉反应;对HA基因及NA基因进行序列分析,结果显示:HA基因与马流感病毒H3亚型同源性最高,NA基因与马流感病毒N8亚型同源性最高,判断该病毒属于H3N8亚型马流感病毒,命名A/EQ/Guangxi/01/09。  相似文献   

4.
本试验采集一只具有流感临床症状的病犬鼻咽拭子经常规处理后接种SPF鸡胚,分离到一株流感病毒,并对其进行鉴定及生物学特性研究。结果表明,该毒株对1%鸡红细胞的血凝价为26,能被H3亚型流感病毒阳性血清中和,与H1、H5、H7、H9亚型阳性血清和阴性血清无交叉反应。序列分析显示,该毒株的HA和NA基因核苷酸序列分别与犬流感病毒(CIV)H3和N2亚型的病毒株同源性最高。确定该毒株为H3N2亚型CIV,并将其命名为A/canine/Guangdong/01/2011。  相似文献   

5.
《中国兽医学报》2016,(10):1696-1700
本试验对1株犬源H3N2亚型流感病毒(A/Canine/Guangdong/10/2014)进行了遗传进化分析。结果显示,本毒株8个基因片段与在中国和泰国分离的H3N2亚型犬流感的关系最近,与当前亚洲分离的毒株高度相似(99%)。基因亚型分析显示8个基因片段和目前流行的H3N2CIVs有相同的基因型(K,G,E,3B,F,2D,F,1E)。本毒株为低致病性的禽源H3N2亚型犬流感,从而证实了禽源犬流感亚型在中国的存在,对流感病毒实施广泛的血清学和流行病学检测,以及对该病的防控具有重要意义。  相似文献   

6.
通过采集一匹患病马的病料及后续的病毒分离、病毒核酸提取、RT-PCR、连接T载体等一系列分子生物学技术,对病毒核酸进行测序,经NCBI比对分析,获得一株H3N8亚型马流感病毒。将获得的毒株与我国分离的A/equine/Jilin/1/1989禽源性毒株、2002年美国肯塔基分离株A/equine/Kentucky/1/02(美洲谱系Florida亚型)、A/equine/Argentine/77(美洲谱系Argentine亚型)等有代表性毒株进行同源性分析,发现该毒株与Florida-2型马流感病毒基因片段的同源率最高。根据马流感病毒的命名规则,将这毒株命名为A/equine/Heilongjiang/1/2010。本次所分离到的黑龙江株马流感病毒,丰富了我国马流感病毒资源库,为我国马流感流行病学研究、诊断技术及疫苗研究提供了重要基础。  相似文献   

7.
[目的]调查山东省聊城市规模化驴场中马流感病毒的感染情况,并分析其可能的来源。[方法]从聊城的规模化驴场采集病料和血清,通过HI试验检测驴血清中的马流感病毒H3N8亚型抗体的阳性率。使用RT-PCR技术扩增肺脏和鼻腔棉拭子样品中的马流感病毒M基因,对获得的马流感病毒M基因与不同流感病毒的M基因进行序列比对,推测其来源。[结果]HI试验表明,120个血清样品中马流感病毒H3N8亚型血清抗体阳性率为33.3%(40/120);其中,母驴的马流感病毒H3N8亚型血清抗体阳性率为42.5%(17/40)、公驴为32.5%(13/40)、驴驹为25.0%(10/40)。通过RT-PCR检测发现,32.3%(21/65)的样品可测出目的条带。通过序列比对得出,该试验获得的流感病毒M基因与马属动物的H3N8亚型流感病毒高度同源(CY032222、CY032318、CY028821等),同源性最高可达99.8%。[结论]马流感病毒在聊城周边的数个规模化养驴场发生流行。该研究从驴体内分离的流感病毒M基因属于马流感病毒H3N8亚型M基因。  相似文献   

8.
为了特异性地检测H3N8亚型马流感病毒,试验根据H3N8亚型马流感病毒(EIV)HA基因特异保守序列设计1对引物,建立了检测H3N8亚型EIV的Eva Green实时荧光定量PCR方法,并对该方法进行评价。结果表明:该方法能特异性地扩增H3N8亚型EIV,而对H7N7亚型EIV、马传染性贫血病毒、马动脉炎病毒、马疱疹病毒均无特异性反应;最低检测限度能达到10拷贝/μL;并且该方法具有良好的重复性。说明Eva Green这种新型荧光染料可以敏感有效地检测EIV,可用于马流感的诊断。  相似文献   

9.
为探索利用高通量测序开展H7N9亚型流感的监测、全基因分析和溯源研究的方法,使用Ion Torrent PGM测序仪对1株H7N9流感病毒进行了全基因测序,分析了此毒株的基因组特性和进化特征。结果显示,该毒株与2013年引起我国华东地区疫情的H7N9流感毒株的亲缘关系较近;纵观在不同年代和地点分离的H7N9流感病毒的6个内部基因,2013年疫情之前和之后的H7N9流感病毒存在明显差异。  相似文献   

10.
2016年4月北京某马场出现马流感疑似疫情,为确诊病原,从发病马群中采集鼻拭子接种鸡胚分离病毒,并进行血凝试验和血凝抑制试验、基因测序和BLAST比对分析。结果表明,从鼻拭子中分离到1株马流感病毒,命名为A/equine/Beijing/2016。血凝试验、血凝抑制试验及测序结果表明,该分离株为H3N8亚型。对分离株的HA基因进行遗传进化分析,表明该分离株属于H3N8亚型美洲谱系的佛罗里达Ⅱ群。对该分离株及国内近年来的马流感病毒分离株的HA氨基酸序列进行分析,发现该分离株相比于OIE推荐的疫苗候选株出现了一个重要的抗原漂移。马流感病毒HA基因的不断变异,提示有必要加强对国内马流感病毒的流行病学监测。  相似文献   

11.
马流感病毒多重RT-PCR检测方法的建立   总被引:4,自引:2,他引:2  
根据马流感病毒的M基因和HA基因的保守序列,设计了两对引物,MF和MR为通用引物,可以检测出H3N8和H7N7亚型EIV,目的片段227bp,HF和HR为H3N8亚型特异性引物,目的片段595bp。利用这两对引物,通过对多重RT-PCR扩增条件的优化,建立了快速检测鉴别H3N8亚型EIV的多重RT-PCR技术。特异性和敏感性试验结果表明,该技术可以用于EIV的快速诊断和亚型鉴定。  相似文献   

12.
13.
H3N8亚型马流感病毒间接ELISA抗体检测方法建立及应用   总被引:5,自引:0,他引:5  
为建立马流感血清学ELISA诊断方法,本研究以马流感病毒中国分离株A/马/新疆/07(H3N8)通过SPF鸡胚培养和增殖,收取含病毒尿囊液经蔗糖密度梯度离心纯化后作为ELISA包被抗原,首次在我国建立了检测H3N8亚型马流感抗体的间接ELISA诊断方法。试验的最佳反应条件为:最佳抗原稀释度7μg/mL,封闭液5%脱脂乳,血清稀释度1∶100,二抗稀释度1∶10000,稀释液PBS(pH7.4),血清反应时间1.5h,二抗反应时间1h。通过本方法对555份临床样品进行检测并与血凝抑制(HI)试验检测结果比较,证明本方法特异、敏感,具有良好的稳定性和可重复性,适于马流感的流行病学调查和监测工作。  相似文献   

14.
为评价马流感病毒(EIV)HA基因核酸免疫效果,本研究以甲病毒复制子载体pSFV1CS分别构建了表达EIV H3N8亚型的美洲型和欧洲型HA基因的重组真核表达质粒。并将其转染293T细胞,经间接免疫荧光鉴定表明HA基因获得表达;以重组质粒免疫的BALB/c鼠能够检测到特异性抗体产生,而且HI抗体水平持续升高,同时小鼠体内IFN-γ、IL-4分泌水平也有所升高。攻毒后小鼠表现轻度临床症状,但病毒分离和RT-PCR均未检测到病毒。上述结果表明,该重组质粒pSFV1CS-EIV-HA具有良好的免疫原性并且可以诱导免疫动物产生较高免疫应答的能力。  相似文献   

15.
2008年从湖北省分离到1株H3N8亚型马流感病毒A/equine/Hubei/6/08。以2002年美国KENTUKY株为模板设计HA基因测序引物,进行RT-PCR,然后测定该分离株的HA基因核苷酸序列。经NCBI上Blast同源性比较发现,与A/equine/Newmarket/5/2003(H3N8)同源性较高为98.7%。HA蛋白遗传进化分析表明该毒株隶属于H3N8亚型马流感病毒中的美洲系福罗里达亚系。该株与OIE现在推荐的疫苗候选株A/equine/Kentuck-y/5/2002(H3N8)HA1蛋白氨基酸序列比对发现有3处氨基酸替换位点;与OIE以往推荐的疫苗候选株A/e-quine/Kentucky/1/1994(H3N8)比对发现有11处氨基酸替换位点。研究结果表明该分离株可作为中国研制马流感疫苗的候选株。  相似文献   

16.
H3N8 canine influenza virus (H3N8 CIV) was first reported as a novel canine respiratory pathogen in racing greyhounds and shelter dogs in the U.S.A. in 2004. Phylogenetic analyses determined that this host-adapted pathogen originated from interspecies transmission of an equine influenza virus (EIV), but it is unknown when the transmission occurred prior to discovery in 2004. The objective of this study was to determine if racing greyhound and shelter dog sera collected from 1984 to 2004 had serological evidence of exposure to H3N8 CIV or EIV. Archived sera from 702 racing greyhounds and 1568 shelter dogs were tested for H3 antibodies to the original 2004 CIV isolate, as well as EIV isolates from 1991 to 1999. None of the racing greyhounds from 1984 and 1985 had detectable H3 antibodies. One of the shelter dogs, which entered a north Florida shelter in 2004, was seropositive. For racing greyhounds sampled from 1999 to 2004, 133/520 (26%) dogs had antibodies to both CIV and EIV H3 proteins. The annual seroprevalence was 27% in 1999, 28% in 2000, 10% in 2001, 1% in 2002, 41% in 2003, and 28% in 2004. The odds of H3 seropositivity were greater among dogs that raced > or =6 months, raced on > or =2 tracks, and raced in 1998, 2002, and 2003. Many of the seropositive dogs raced at tracks that were involved in 'kennel cough' epidemics in 1998-1999 and 2002-2003. Based on serological evidence, a H3N8 canine influenza-like virus was circulating in racing greyhounds in the U.S.A. as early as 1999.  相似文献   

17.
Equine influenza and equine rhinopneumonitis are among the Office International des Epizooties or the World Organisation for Animal Health notifiable, contagious respiratory diseases. Although vaccination of horses in Israel against equine influenza virus (EIV) and against equine herpesvirus (EHV) is routinely performed, information regarding the occurrence and the epidemiology of the diseases is lacking. We hereby attempt to determine seroprevalence and rate of infection for EHV-1 and 4 and for EIV in horses distributed throughout Israel and describe demographic and environmental risk factors associated with seroprevalence. Despite the fact that last reported isolation of EIV in Israel occurred in 2007, we found a 26.4% (29/110) (95% confidence interval [CI]: 18.18–34.62) seroprevalence for H3N8, a 16.4% (18/110) (95% CI: 9.49–23.31) for H7N7, and a 6.4% (7/110) (95% CI: 1.83–10.97) rate of seroconversion for H3N8, suggesting current and active circulation of EIV in horses in Israel. Age, housing management type, and type of farm activity were significantly associated with seroprevalence, with activities allowing exposure to new horses positively associated with seroprevalence to EIV and an only pasture housing management negatively associated with seroprevalence. No association was detected between other demographic variables (gender, breed, and color) and environmental factors (climatic regions). Seroprevalence to EHV-1 and 4 were very low (<1%) and very high (>99%), respectively, raising questions regarding the appropriate vaccination guidelines. Our findings of the occurrence of EIV in horses in Israel imply an underdiagnosis of this virus in this country and warrant further investigation as to the strains that circulate in this region and their accordance with the current vaccine strains.  相似文献   

18.
The ecology of avian influenza (AI) viruses in wild aquatic birds of Asia is poorly understood, especially for the H5N1 high pathogenicity AI (HPAI) viruses. From March 2006 through November 2008, 20 AI viruses were isolated in the Crimea region of Ukraine with an overall frequency of virus recovery of 3.3%. All the viruses were isolated from three species of dabbling ducks: mallard (Anas platyrhynchos), wigeon (Anas penelope), and garganey (Anas querquedula), making the frequency of virus recovery for dabbling ducks 6.3%. The viruses were predominantly isolated during the fall sampling period. All viruses were genetically and antigenically characterized. No H5N1 HPAI viruses were isolated, but other HA and NA subtypes were identified including H3N1 (2), H3N6 (3), H3N8 (4), H4N6 (6), H5N2 (3), H7N8 (1), and H10N6 (1) subtypes. All isolates were of low pathogenicity, as determined by the intravenous pathogenicity index of 0.00. For H5N2 and H7N8 isolates, the HA gene was sequenced and the phylogenetic analysis revealed possible ecologic connections of the Crimea region with AI viruses from Siberia and Europe. No influenza A isolates were recovered from other Anseriformes (diving ducks [two species of pochards] and graylag geese), Columbiformes (collared doves), Gruiformes (coot), and Galliformes (gray partridges).  相似文献   

19.
2006年6月-2007年10月,从云南省16个地州随机采集的各种家禽、家猪的喉气管和口腔棉拭子样品7 901份,应用RT-PCR结合血凝、血凝抑制试验和抗原捕捉ELISA,检测H9N2亚型禽流感感染情况,选择具有代表性的阳性样品,克隆NA全基因并进行基因序列分和推导氨基酸的糖基化位点分析。结果表明,云南省2006-2007年H9N2亚型禽流感病毒在全省14个地州均有流行,感染宿主包括鸡、鸭、鹅和猪;分离的19个毒株中的13个鸡源和1个鹅源毒珠的NA全基因长1 407bp,编码469个氨基酸,同源性为96.1%~99.6%,是目前云南省流行的优势亚群;3个鸭源毒株、1个鹅源和1个猪源毒株NA基因长1 398bp,编码466个氨基酸,5个非鸡源毒株的NA基因的同源性为99%,构成云南目前流行的另一分支,推导氨基酸第61~63位3个氨基酸的缺失是与优势分支的特征性区别;2个分支间NA基因同源性为90%,与国内外其他毒株比较神经氨酸酶基因序列具有多态性。  相似文献   

20.
A 4‐year‐old Warmblood mare presented to the William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California at Davis with bilateral mucoid nasal discharge and pyrexia. The mare had recently been imported from Germany, arriving at a quarantine holding facility 72 h prior to presentation. Based on clinical presentation and culture results of tracheal fluid, the mare was diagnosed with bacterial bronchopneumonia secondary to equine influenza. The equine influenza virus (EIV) identified in the imported mare displayed 99.1% nucleotide homology of the HA1 gene to the prototype Florida sublineage clade 2 isolate A/equine/Richmond/1/2007 (H3N8). This case illustrates the risk of introducing a clade 2 EIV in North America.  相似文献   

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