辽宁省首次从动物体内分离到O157：H7大肠杆菌

１９９８年４月～５月间，在沈阳市内某屠宰场采集动物粪便及肉制品、首次在猪粪、猪肉中检出２种不同类型的Ｏ１５７：大肠杆菌，其中Ｏ１５７：Ｈ７２株，Ｏ１５７：Ｈ？３株。将分离出的５株菌进行血清、生化鉴定均符合大肠杆菌特点     

能与大肠杆菌O157(H7)抗血清交叉凝集的5种细菌的分离和鉴定

「目的」了解人兽及食品中能与大直菌Ｏ１５７发生交叉凝集的细菌，为防止误诊提供参考。「方法」开展调查，用大肠杆菌Ｏ１５７及Ｈ７抗血清、Ｏ１５７单克隆抗体进行玻片凝集、生化试验等检测。「结果」从肉类及猪粪中检出５种（８侏）肠道杆菌能与Ｏ１５７抗血清发生交叉反应，其中４种为国内外首次报道，２株检出菌且能与Ｈ７抗血清凝集，４株能产生ＬＴ肠毒素。「结论」畜禽中某些各属的肠道细菌可携带与大肠杆菌Ｏ１５７及Ｏ１     

O157：H7大肠杆菌感染症研究概况

Ｏ１５７：Ｈ７大肠杆菌感染症研究概况刘炳智综述１９９６年５～８月，在日本东京、大阪、京都等都府县相继发生由Ｏ１５７：Ｈ７大肠杆菌引起的大规模的集体中毒事件，患者累计９０００多人，死亡７人，上百所中小学因此停课，此起彼伏的集体食物中毒事件不仅惊扰了整个...     

O157：H7大肠杆菌感染的研究进展

Ｏ１５７：Ｈ７大肠杆菌感染的研究进展杨平１薛峰１胡作林１综述Ｏ１５７：Ｈ７大肠杆菌（简称Ｏ１５７：Ｈ７）作为一种新型肠道致病菌被确认，是近年来在食品卫生及肠道感染领域中最重要的研究进展之一。感染此菌可使人患腹泻、出血性结肠炎（ＨＣ），也可引发溶血性尿...     

应用多重引物PCR技术检测O157∶H7毒力基因

目的 对江苏省６个不同地区不同宿主动物中分离的Ｏ１５７：Ｈ７菌株进行毒力基因的检测分析。方法 应用肠出血性大肠杆菌（ＥＨＥＣ）的多重引物聚合酶链反应（ＰＣＲ）方法,以志贺祥毒素（ＳＬＴ２和ＳＬＴ１）基因、“粘附抹平”因子ｅａｅＡ基因和溶血素（ｈｌｙ）基因为靶基因进行检测。结果 江苏省分离的Ｏ１５７：Ｈ７菌株毒力基因携带率为５６．５％,不同地区的分离株携带率有所不同,个别地区高达９０％以上,有的地区     

福建省O157大肠杆菌调查

目的 探索Ｏ１５７大肠杆菌在福建省人兽及食物中的存在情况,并了解这些检出菌的生物学特性。方法 １９９７～１９９８年选莆田、福州等地检查腹泻患粪便、畜食粪便标本及肉类标本２７２５份,以血清学方法检测Ｏ１５７大肠杆菌。结果 先从猪、鸽、牛、鸡、鸭等动物及腹泻中检出７６株Ｏ１５７大肠杆菌。据血清学及动力试验结果分类,３３株Ｏ１５７：Ｈ７,２１株Ｏ１５７：ＮＭ,２２株Ｏ１５７：Ｈ？,其中以猪检出率最高     

大肠杆菌O157：H7的实验诊断

Ｏ１５７：Ｈ７大肠杆菌是近年引起世界广泛关注的肠道病原菌。自１９８２年美国密执安和俄勒岗州因进食被污染的汉堡包发生食物中毒，并从患者分离到该菌以来，１９９６年５～８月，日本东京、大阪等地相继发生该菌引起的大规模食物中毒，引起世界关注。本文就Ｏ１５７：...     

大肠杆菌O157∶H7分离株的生物学特性分析

采用血清学、ＰＣＲ技术、生化反应、药敏试验、Ｖｅｒｏ细胞毒素测定等方法,对分离到的７株肠出血性大肠杆菌Ｏ１５７∶Ｈ７菌株进行了综合分析。表明试验菌株用Ｏ１５７单克隆抗体和Ｏ１５７∶Ｈ７血清在做玻片凝集时,模式均较好;Ｈ７血清做试管定量凝集试验时亦均达到要求的稀释度以上;特异性ＰＣＲ技术检查时,测得１株试验菌株带有毒力基因;经全自动微生物鉴定系统检测２８种生化反应时,有１８种生化反应与９３３菌株完全相同,其余１０种生化反应各有不同,其中与９３３菌株有５种生化反应不同的有四株,４、３、１种生化反应不同的各一株。未发现与９３３菌株生化特性完全相等的菌株,亦未发现试验菌株间生化特性完全相同的。１２种常用抗菌素药敏试验显示对氯霉素、丁胺卡那霉素、菌必治均为敏感。对其它抗菌素均有不同程度的耐药。     

污水等环境中O157大肠杆菌的研究

「目的」了解生活及养殖污水等环境中是否存在Ｏ１５７大肠杆菌。「方法」选市区、郊区饲养场、屠宰场、农贸市场、医院和居民生活污水等作为调查对象,按季节定时定点采集污水、禽畜粪便和市场丰板等标本进行Ｏ１５７大肠杆菌分离培养、鉴定。「结果」从养猪场、屠宰场、市场污水和生活污水以及猪粪、鸡粪、猪肉砧板中检出２类Ｏ１５７大肠杆菌（Ｏ１５７：Ｈ７和Ｏ１５７：ＮＭ）。并发现夏秋季污水等环境中Ｏ１５７大肠苗菌检出率     

浙江省首例肠出血性大肠杆菌O157：H7菌株的分离和鉴定

在１９９７年对杭州地区肠道门诊腹泻患者肠出血性大肠杆菌（ＥＨＥＣ）感染调查中,应用山梨醇麦康凯培养基于一慢性腹泻患者粪便中分离到 首株ＥＨＥＣＯ１５７：Ｈ７菌株,并对此进行初步鉴定。该菌株为革兰氏阴性杆菌,具大肠杆菌生化特性,但与大多数国外已报道的菌株不同,发酵山梨醇,棉子、卫茅醇、赖氨酸、鸟氨酸等均阴性;Ｏ１５７及Ｈ７抗因清玻片凝集试验和试管定量凝集试验结果均生;未检出ＳＬＴ－Ｉ、ＳＬＴ－Ⅱ和溶     

大肠埃希菌O157:H7分离鉴定过程中赫尔曼埃希菌的鉴别

目的：鉴别大肠埃希菌O157：H7和赫尔曼埃希菌。方法：观察菌株在山梨醇麦康凯，营养琼脂及Chromagar O157培养基上菌落形态。生化试验检测菌株的生化特性，血清凝集试验检测菌株的O157和H7抗原，聚合酶链反应法检测O157和H7特异性基因。结果：在营养琼脂培养基上，5株赫尔曼埃希菌均产黄色色素，2株O157：H7菌不产色素；在Chromagar O157培养基上，2株O157：H7菌株呈紫红色，2株赫尔曼埃希菌株呈蓝色，其余3株赫尔曼埃希菌株呈黄绿色。O157：H7菌株KCN试验均为阴性，而赫尔曼埃希菌阳性。O157和H7抗血清坡片凝集试验，7析均为强凝集。O157：H7菌株与O157单克隆抗血清玻片凝集试验均为强凝集，而赫尔曼埃希菌均不凝集。O157：H7菌株O157和H7特异性基因均为阳性，赫尔曼埃希菌均为阴性。结论：赫尔曼埃希菌与O157多克隆抗血清有交叉反应，但单克隆抗血清能区分O157：H7和赫尔曼埃希菌。KCN试验和特异性基因检测亦能鉴别这两种菌。在营养琼脂和Chromagar O157培养基上的菌落形成也有助于两菌的区分。     

Detection of Escherichia coli O157:H7 and Listeria monocytogenes in beef products by real-time polymerase chain reaction

Rapid methods for the detection of Escherichia coli O157:H7 and Listeria monocytogenes in food products are important to the food industry and for public health. Conventional microbiological methods and newly developed molecular-based techniques such as polymerase chain reaction (PCR)-based methods are time consuming. In this study, a faster method based on utilization of a hybridization probe with real-time PCR, was developed and applied for detection of E. coli O157:H7 and L. monocytogenes from artificially contaminated raw ground beef and fully cooked beef hotdogs. Target genes for E. coli O157:H7 and L. monocytogenes were rfbE and hylA, respectively. An analysis of 169 bacterial strains showed that the chosen primers and probes were specific for detection of E. coli O157:H7 and L. monocytogenes by real-time PCR. The assay was positive for nine of 10. E. coli O157:H7 strains, and all L. monocytogenes (7/7) strains evaluated. Bacterial strains lacking these genes were not detected by these assays. Detection limits of real-time PCR assays ranged from 10(3) to 10(8) colony forming units (CFU)/ml for E. coli O157:H7 in modified tryptic soy broth and 10(4) to 10(8) CFU/mL for L. monocytogenes in Fraser Broth. Detection sensitivity ranged from 10(3) to 10(4) CFU/g of raw ground beef or hotdog without enrichment for E. coli and L. monocytogenes. Approximately 1.4-2.2 CFU/g of E. coli O157:H7 in raw ground beef were detected following an enrichment step of 4 h. Approximately 1.2-6.0 CFU/g of L. monocytogenes in beef hotdogs were detected following an enrichment step of 30 h. The real-time PCR assays for detection of E. coli O157:H7 and L. monocytogenes in raw ground beef and beef hotdogs were specific, sensitive and rapid.     

12株疑似O157:H7大肠菌PCR鉴定研究

目的:对12株疑似O157:H7大肠菌采用PCR法进行鉴定。方法:利用单一PCR和多重聚合酶链反应(mPCR)检测不同来源菌株志贺样毒素(stx1和stx2)、溶血素(hly)、粘附抹平因子(eaeA)、β-葡糖醛酸糖苷酶(u idA)、O157抗原编码(rfbE)、H7鞭毛抗原编码(fliC)基因。结果:4株大肠菌rfbE和fliC基因检测为阳性,确认为EHEC O157:H7,其中1株菌株扩增出全部毒力基因,另3株菌株扩增出除stx1外其它全部毒力基因;2株大肠菌rfbE基因检测阳性,确认为O157:H7-大肠菌;其它均为非O157:H7其它大肠菌。结论:PCR技术的应用能对可疑O157:H7大肠菌进行有效鉴定与分析,应成为今后病原学鉴定的主要技术手段。     

2007年浙江省衢州地区动物中产志贺毒素大肠埃希菌O157:H7感染状况

目的:了解2007年浙江省衢州地区产志贺毒素大肠埃希菌O157:H7在动物中的分布情况及其耐药性、PFGE分型及毒力基因携带状况。方法:按全国O157:H7监测方案于5~10月份肠道传染病高发季节,在衢州地区采集各种动物粪便/肛拭,用免疫磁珠富集后进行O157:H7分离培养、鉴定,可疑菌株以PCR法检测O、H抗原及志贺样毒素(SLT1和SLT2)、粘附抹平因子(eaeA)及溶血素(hly)4种毒力基因。用脉冲场凝胶电泳(pulse field gel electrophoresis,PFGE)方法进行同源性分析,同时选择14种抗生素进行药敏试验,分析分离所得菌株的耐药状况。结果:共监测动物粪便标本300份,分离得产志贺毒素大肠埃希菌O157:H7菌株16株,分离率为5.33%。16株O157:H7菌株,毒力基因Hly、eaeA、SLT2均阳性,SLT1均阴性。脉冲场凝胶电泳分型显示,16株O157:H7菌株可分2个PFGE基因型,型间差异较小。耐药性分析显示这些菌株对红霉素、利福平的耐药率最高,达100.0%,对其他受试抗生素均敏感。结论:该地区动物中产志贺毒素大肠埃希菌O157:H7带菌率较高,所分离菌株主要携带SLT2基因,因此推测该地区存在发生产志贺毒素大肠埃希菌O157:H7感染暴发或流行的潜在危险,需增加对动物源性O157:H7的监测力度。     

Sorbitol-fermenting, β-glucuronidase-positive, Shiga toxin-negative Escherichia coli O157:H7 in free-ranging red deer in South-Central Spain

We investigated the prevalence of Escherichia coli O157:H7 in free-ranging red deer in south-central Spain, to assess their potential as reservoir hosts of sorbitol-fermenting (SF) E. coli O157:H7 strains, which are emerging causes of hemolytic uremic syndrome in Europe. Fecal samples from 264 hunter-harvested Iberian red deer (Cervus elaphus) were collected in 25 different game estates and examined for E. coli O157:H7 by culture and PCR. E. coli O157:H7 was detected and isolated in 4 of the 25 game estates sampled (16%) and the isolates obtained (four in total) were further phenogenotypically characterized. One of them was biochemically typical of E. coli O157:H7, that is, neither fermented sorbitol nor exhibited β-glucuronidase (GUD) activity, and carried genes encoding Shiga toxins (Stx) 1 and 2, the intimin subtype γ1, the enterohemorrhagic E. coli (EHEC)-hemolysin, and the ter gene cluster. The rest of the isolates (three of four) fermented sorbitol, exhibited GUD activity after 18-24?h incubation, and carried genes encoding the intimin subtype γ1 and the EHEC-hemolysin, although no Stx-encoding genes were detected. All these atypical isolates carried the sfp gene cluster, lacked the ter gene cluster, and were unable to grow on cefixime tellurite sorbitol MacConkey agar, which are typical features of SF E. coli O157:H7 strains isolated from patients. In total, SF, GUD-positive, Stx-negative E. coli O157:H7 strains were isolated in 3 of the 25 game estates sampled (12%), with an overall sample-level prevalence of 1.1% (3/264). Our findings indicate that free-ranging red deer may be one of the possible reservoir hosts of Stx-negative derivatives of SF E. coli O157:H7.     

不同来源产志贺毒素大肠埃希菌分布特征

目的探讨不同标本中产志贺样毒素大肠埃希菌（STEC）的分布特征。方法采集动物粪便、肉类食品和排污口污泥样品，常规分离大肠埃希菌，血清学分型，PCR鉴定产志贺样毒素（stx1，stx2）菌株。结果293份标本中鉴定出8株STEC，1株为产志贺毒素O157：H7型，2株为不产志贺毒素O157：H7型，5株为产志贺毒素非O157：H7型。结论STEC存在于不同来源的标本中，菌株表型与毒力因子存在一定差异。     

Prevalence, structure and expression of urease genes in Shiga toxin-producing Escherichia coli from humans and the environment

A component of the ure gene cluster in E. coli, ureC, encodes a subunit of urease. We have investigated the distribution of ureC in 202 Shiga toxin-producing E. coli (STEC) strains from Austria belonging to 61 different serotypes. These strains were of human (n=150), animal (n=38), and food (n=14) origin. ureC was present in all 72 E. coli O157:H7 and O157:NM (non-motile) strains, as well as in all 29 strains of serotypes O26:H11/NM, O111:H8/NM and O145:NM. In contrast, none of eight sorbitol-fermenting E. coli O157:NM were ureC-positive. ureC occurred significantly more frequently among STEC that carry eae (113 of 132; 85.6%) than among eae-negative STEC strains (four of 70; 5.7%; p<0.0001). However, only 4 (2%) of the 202 strains (3.4% of ureC positive strains) expressed urease activity. There was no significant association (p=0.56) between urease expression and the source of the isolates (humans vs. animals). Nucleotide sequence analysis of PCR amplicons derived from all seven genes of the ure cluster in STEC of 10 different serotypes demonstrated a high degree of homology (>or=99%), indicating a recent acquisition of not necessarily expressed ure genes.     

Ongoing multistate outbreak of Escherichia coli serotype O157:H7 infections associated with consumption of fresh spinach--United States, September 2006

On September 13, 2006, CDC officials were alerted by epidemiologists in Wisconsin and Oregon that fresh spinach was the suspected source of small clusters of Escherichia coli serotype O157:H7 infections in those states. On the same day, New Mexico epidemiologists contacted Wisconsin and Oregon epidemiologists about a cluster of E. coli O157:H7 infections in New Mexico associated with fresh spinach consumption. Wisconsin public health officials had first reported a cluster of E. coli O157:H7 infections to CDC on September 8. On September 12, CDC PulseNet had confirmed that the E. coli O157:H7 strains from infected patients in Wisconsin had matching pulsed-field gel electrophoresis (PFGE) patterns and identified the same pattern in patient isolates from other states. This report describes the joint investigation and outbreak-control measures undertaken by state public health officials, CDC, and the Food and Drug Administration (FDA). This investigation and additional case finding are ongoing.     

大肠杆菌O157多克隆抗体及食品中双抗ELISA测定方法的研究

本研究获得了抗肠出血性大肠杆菌O157:H7的多克隆抗体 ,建立了一种适宜食品样品检测的双抗ELISA检测方法。该方法对纯培养菌液检出限为 10 3 ～ 10 4 cfu ml;只对O157菌株有特异性反应 ,对非O157菌株无交叉反应 ;经过增菌 ,鸡肉与牛奶染菌样品中的大肠杆菌O157的检出限均为 0 1cfu g(cfu ml)。