副溶血性弧菌引起食物中毒的同源性研究

目的:探讨深圳市龙岗区由副溶血性弧菌O3:K6型引起食物中毒的分子流行病学研究和同源性分析.方法:收集不同地区、不同时期食物中毒事件的副溶血性弧菌菌株,并从7宗相同血清型O3:K6的溶血性弧菌菌株中,每宗取1株副溶血性弧菌进行生化鉴定、血清学分型、脉冲场凝胶电泳(PFGE)分析.结果:7株副溶血性弧菌,它们的血清型均为O3:K6,脉冲场凝胶电泳(PFGE)分析结果显示,有2株副溶血性弧菌图谱一致,具有高度的同源性;5株副溶血性弧菌为紧密相关.结论:通过PFGE分子分型的方法了解到该血清型O3:K6的副溶血性弧菌菌株之间具有紧密相关和高度的同源性,表明副溶血性弧菌血清型O3:K6是该地区引起腹泻的主要菌型.     

食物中毒中副溶血性弧菌的毒力基因及同源性分析

目的探讨无锡一起食物中毒事件中副溶血性弧菌分离株的毒力基因、耐药性及分子分型情况。方法对5份食品样品、8份环境涂抹样品、7份患者肛拭子、1份厨师肛拭子分别进行致病菌的分离鉴定、毒力基因检测、血清学分型、药敏试验以及脉冲场凝胶电泳(PFGE)图谱分析。结果分离自患者肛拭子的6株副溶血性弧菌血清型为O3∶K6型,毒力基因检测跨膜转录激活蛋白基因(tox R)阳性,耐热直接溶血素基因(tdh)阳性,耐热相关溶血素基因(trh)阴性,PFGE分型图谱一致;分离自食品和环境的2株副溶血性弧菌血清型为O4∶K42型,毒力基因检测tox R阳性,tdh阴性,trh阴性,PFGE分型图谱一致;两者之间的同源性50%。8株副溶血性弧菌对临床常用的8种抗生素均敏感。结论该起食物中毒由O3∶K6型副溶血性弧菌感染引起,排除了所采集食品和环境样品被污染作为传染源的可能。     

副溶血性弧菌临床分离株血清型、毒力基因和PFGE分子分型特征分析

目的分析从2007-2012年腹泻病例标本中分离的168株副溶血性弧菌血清型分布、毒力基因携带情况和PFGE分子分型特征。方法采用血清学凝集实验,检测菌株的血清型别;采用实时荧光PCR方法,检测耐热性溶血毒素基因(tdh)和耐热性溶血毒素相关溶血毒素基因(trh);采用脉冲场凝胶电泳技术(PFGE),分析56株O3∶K6型副溶血性弧菌的基因分型特征。结果 (1)168株菌可分为14种血清型,主要血清型为O3∶K6(114,67.9%)、O4∶K8(25,14.9%)、O3∶K29(6,3.6%);食物中毒分离株与腹泻门诊分离株血清型构成不同,但优势血清型均为03∶K6。(2)168株菌可分为4种毒力基因类型,分别为tdh+trh-(161,95.8%)、tdh+trh+(3,1.8%)、tdh-trh+(1,0.6%)、tdh-trh-(3,1.8%);食物中毒分离株与腹泻门诊分离株毒力基因类型构成不同,但优势毒力基因类型均为tdh+trh-。(3)56株O3∶K6型副溶血性弧菌共有15种PFGE带型(P1～P15),相似度>86%,有10个带型分别有多株菌处于同一聚类(P1～P4、P6、P7、P9、P10、P12、P15)。结论副溶血性弧菌临床分离株以tdh+trh-的O3∶K6为主;O3∶K6型副溶血性弧菌临床分离株的PFGE条带型相似性度高,菌株间亲缘关系较近。     

广州地区70株副溶血性弧菌病原学特征分析

目的 了解广州地区人源性和食源性副溶血性弧菌优势血清型、携带毒力基因和分子分型情况。方法 收集2014 - 2016年广州地区腹泻患者和食源性监测中分离到的副溶血性弧菌进行血清分型、毒力基因鉴定和脉冲场凝胶电泳分型（PFGE）。结果 70株副溶血性弧菌,临床分离株48株,血清型分别为O3∶K6、O4∶K8、O1∶K1、O4∶K9、O1∶K36,其中O3∶K6为主要型别（70.8%）,其次为O4∶K8（20.8%）。食品分离株22株,血清型分散无明显优势。毒力基因检测,临床分离株46株tdh、toxRS/new、orf8全部阳性。食品分离株6株tdh阳性,toxRS/new、orf8全部阴性。所有菌株均未检出trh基因。PFGE分析70株副溶血性弧菌可分为45种带型,2种聚类,菌株间的相似值为45.6 %～100 %。结论 副溶血性弧菌临床分离株与食品分离株在血清型和毒力基因分布上具有分离现象。引起广州地区食源性疾病的副溶血性弧菌株,是主要以携带tdh、toxRS/new、orf8基因的O3:K6型菌株。PFGE图谱显示,本区域70株副溶血弧菌呈现基因多样性。     

一起O3:K6型副溶血性弧菌引起的食物中毒实验室分析

目的:通过流行病学调查和实验室检测结果分析食物中毒原因。方法:参照GB/T4789-2004方法[1]对病人粪便或肛拭、剩余食物、食物加工环节涂抹物进行病原菌检测,对检出的副溶血性弧菌作血清分型及神奈川溶血试验。结果:19份病人标本中检出14株副溶血性弧菌,并从海虾和加工环节涂抹物中各检出1株副溶血性弧菌,血清型均为O3:K6型,神奈川溶血阳性(KP)。结论:本次食物中毒是由具较强毒力的O3:K6型副溶血性弧菌污染引起的。     

一起副溶血性弧菌食物中毒的调查与分析

目的分析食物中毒的原因,查明致病菌。方法对14例食物中毒患者进行流行病学调查,3例食物中毒患者肛拭子、1份粪便标本及7份剩余菜肴进行病原菌的分离、鉴定,并对分离菌株进行血清学分型、毒力基因多重PCR检测tdh、trh和toxR基因试验、脉冲场凝胶电泳(PFGE)分子分型。结果 3份食物中毒患者肛拭子、1份粪便标本中均检出副溶血性弧菌,经血清学分型、毒力基因多重PCR检测、PFGE分子分型试验,4份患者标本的分离株试验结果完全一致。均为副溶血性弧菌,血清型为O4∶K9,毒力基因tdh阳性、trh阴性和toxR阳性,脉冲场凝胶电泳图谱的聚类分析结果显示:4株副溶血性弧菌的带型相似度为100%。7份剩余菜肴均未检出相关致病菌。结论根据流行病学调查,实验室检测分析,这是一起由副溶血性弧菌污染食物所致的食物中毒。     

一起副溶血性弧菌引起食物中毒的病原学鉴定及分型

目的对食物中毒事件中所采集样本进行副溶血性弧菌的分离鉴定,快速查明食物中毒原因并进行同源性分析。方法采用现行标准检验方法及实时荧光定量PCR对样本进行副溶血性弧菌分离鉴定;采用脉冲场凝胶电泳(PFGE)对分离到的副溶血性弧菌进行分子分型。结果运用标准检验方法在22份食物样本中分离到副溶血性弧菌1株,7份粪便样本中分离到5株;实时荧光定量PCR在食物样本中检出核酸阳性1份,粪便样本中检出6份;所分离到的6株副溶血性弧菌经PFGE聚类分析得到4种PFGE带型,指纹图谱相似度为93.48%~97.44%。结论此次食物中毒由同一克隆副溶血性弧菌污染所致,PFGE可有效用于食物中毒的分型研究及溯源分析,实时荧光PCR可作为现行标准检验方法的有效补充。     

长沙地区8起副溶血性弧菌食物中毒的病原学特征分析

目的了解长沙地区副溶血性弧菌食物中毒的病原学特征,为预防和控制由副溶血性弧菌引起的食源性疾病提供科学依据。方法对2015年长沙地区8起食物中毒事件中分离的21株副溶血性弧菌进行血清学分型,PCR检测毒力基因tdh和trh,微量肉汤稀释法测定抗生素敏感性,脉冲场凝胶电泳进行分子分型。结果 21株副溶血性弧菌均为O3∶K6血清型;tdh携带率为100%,未检测到trh阳性菌株;分离菌株对氨苄青霉素耐药率为14.29%,对四环素、氯霉素等其他7种抗生素均敏感;分离株PFGE带型相似度高(85%)。结论长沙地区引起食物中毒的副溶血性弧菌主要为O3∶K6血清型,菌株都携带tdh毒力基因且相似度高。     

广东省2009年副溶血弧菌暴发与散发菌株的病原学特征分析

目的 了解2009年广东省副溶血弧菌食物中毒分离株和腹泻患者监测分离株的血清分型、毒力基因携带情况及分子特征.方法 对95株副溶血弧菌食物中毒分离株和15株腹泻患者分离株进行血清分型,耐热直接溶血素相关基因(trh)和耐热直接溶血素基因(tdh)PCR检测以及选取不同血清型副溶血弧菌81株进行脉冲场凝胶电泳(PFGE)分子分型.结果 从监测腹泻患者分离的15株副溶血弧菌,血清型以O3:K6(46.67％)和O4:K8(33.33％)为主;从11起副溶血弧菌食物中毒分离的95株菌,血清型以O3:K6(44.21％)和O4:K8(28.42％)居多;7株食品分离株都不是O3:K6血清型;93株(84.54％)为tdh+ trh-菌株,13株(11.81％)为tdh-trh菌株,3株(3.65％)为tdh+ trh+菌株.81株副溶血弧菌的PFGE相似值为57.7％～100.0％,被分为36种不同的PFGE型别,PFGE001型和029型为2009年广东省副溶血弧菌优势PFGE型别.结论 2009年广东省引起感染性腹泻和食物中毒的副溶血弧菌以O3:K6和O4:K8型为主要血清型,多数菌株携带tdh基因,存在优势PFGE型别菌株不断引起各地区的散发和暴发.     

1起副溶血性弧菌食物中毒的菌型鉴定及同源性分析

目的对1起副溶血性弧菌引起的食物中毒进行菌型鉴定及同源性分析,为食物中毒疫情处置提供参考。方法采集病例和食物、外环境标本进行菌株型别的分离鉴定,并对菌株同源性进行分析。结果共采集标本17份,其中3份外环境标本和5份病例标本检出副溶血性弧菌,病例菌株血清型均为O3:K6,环境菌株血清型为O4:KUT和O1:KUT。所有菌株trh基因阴性,病例菌株tdh阳性,环境菌株tdh阴性。脉冲场凝胶电泳(PFGE)指纹图谱显示所有病例菌株具有相同的PFGE图谱,与环境菌株的PFGE图谱的相似性为64.1%。结论该起食源性疾病暴发疫情是由O3:K6型副溶血性弧菌引起的食物中毒事件。     

进口冻肉中小肠结肠炎耶尔森氏菌检出情况分析

目的：了解我国进口冻肉产品中小肠结肠炎耶尔森氏菌的检出情况，为此类产品的风险分析和检验检疫工作提供依据。方法：通过采用小肠结肠炎耶尔森氏菌的国标检验方法和VITEK、API生化鉴定仪对247份进口冻肉产品进行检测。结果：247份样品中共检出耶尔森属菌33份，其中17份为小肠结肠炎耶尔森氏菌，检出率为6．88％，均属于生物1A型，其中3株为血清O：8型，其余均属非常见血清型。阳性样品中16份为冻鸡类样品，1份为冻猪肉类样品。94份海产样品无一份检出。结论：通过实验数据分析我国进口的冻肉产品中冻鸡类产品检出小肠结肠炎耶尔森氏菌比率较高，而海产品和冻猪肉产品中检出率相对较低，所以认为冻鸡类产品小肠结肠炎耶尔森氏菌污染风险较高，应加强此类产品检验监管力度。     

Isolation of free DNA from archived serum samples suitable for molecular genetic studies

INTRODUCTION: Collected and archived serum samples could be important sources for genetic studies, once DNA suitable for molecular genetic studies could be obtained from them. METHODS: DNA was isolated from 54 archived sera samples, collected previously from the participants of a Hungarian allergy study, with commercially available isolation kit. The authors have determined the concentration of the isolated DNA (81.88 +/- 52.36 ng/ml) and the size of the isolated fragments was estimated using semiquantitative real-time PCR. Two primers were used producing two different fragment size, for the phospholipase 2A and the actin beta genes, and melting curve analyses was performed as quality control. RESULTS: The concentration of the phospholipase 2A product was 2.9798 +/- 5.4454 microg/microl and the actin beta gene was 0.0015 +/- 0.0011 microg/microl. The melting curve analysis served as a quality control for the determination of the size of PCR products. In the case of the phospholipase 2A all samples produced the 133 bp PCR fragments, except one, while in the case of actin beta gene only six sample showed the expected 178 bp product, all the others samples had smaller fragments. CONCLUSIONS: These results confirm the suitability of the DNA isolated from archived sera samples for further molecular biological studies (SNP analysis, mutation detection) and give an estimate for the product size of the isolated DNA. Sera samples have been collected years ago can be a good source of genetic information on different diseases.     

Analysis of thermostable direct hemolysin-producing Vibrio parahaemolyticus by pulsed-field gel electrophoresis

OBJECTIVES: We investigated the source of thermostable direct hemolysin-producing Vibrio parahaemolticus infection (positive strains) that causes Vibrio parahaemolticus food poisoning. METHODS: We investigated the coincidence rate of serotypes isolated from samples of sea water used to store clams in 1998 in Shizuoka Prefecture, and those isolated from patients who developed symptoms of food poisoning in the same year. Furthermore, using isolated types 03:K6 and 04:K68, We treated the chromosomal DNA with a restriction endonuclease Sfi I and compared the digestion patterns by pulsed-field gel electrophoresis (PFGE). RESULTS: (1) Of 225 samples of sea water used to store clams, the thermostable direct hemolysin gene was detected in 23 samples by the PCR method. Among these 23 samples, 10 positive strains were detected in five samples. The serotypes of these productive strains were 03:K6 (four isolates), 03:K37 (two isolates), 04:K8 (one isolate), 04:K9 (two isolates) and 04:K68 (one isolate). (2) The five serotypes isolated from the sea water samples were consistent with those of 17 of 17 cases (100%) of which serotypes could be confirmed by this institute and 94 of 100 strains (94%) isolated in a large scale outbreak of food poisoning that occurred in the same year. (3) Using types 03:K6 and 04:K68 isolated from sea water samples and patients, chromosomal DNA were compared among the isolates by PFGE. As a result, of 28 isolates examined, 26 isolates showed a similar electrophoretic migration pattern between the sources and serotypes. CONCLUSION: The etiologic strains for Vibrio parahaemolyticus food poisoning appear to have been derived from the environment. Regarding the findings that types 03:K6 and 04:K68 showed a similar electrophoretic migration pattern, these types can be considered to belong to the same PFGE type.     

聚合酶链反应检测空调冷却水中的嗜肺军团菌DNA

目的: 检测中央空调系统冷却水的嗜肺军团菌污染状况。方法: 建立了嗜肺军团菌MIP基因DNA的PCR检测方法,并对中央空调冷却水进行了嗜肺军团菌DNA的检测, 同时使用了BYCE培养基进行标本的军团菌分离培养。结果:在所有30 个受测系统水样中, 有12 (40% ) 个嗜肺军团菌DNA检测阳性, 与此同时只有6 个嗜肺军团菌经BYCE培养基培养阳性, 两种方法敏感性差别有统计学意义 (P< 0.05)。结论: 中央空调冷却水中嗜肺军团菌的污染有相当的普遍性     

Detection of sorbitol-negative and sorbitol-positive Shiga toxin-producing Escherichia coli, Listeria monocytogenes, Campylobacter jejuni, and Salmonella spp. in dairy farm environmental samples

Six visits were conducted to four dairy farms to collect swab, liquid, and solid dairy farm environmental samples (165 to 180/farm; 15 sample types). The objective of the study was to determine on-farm sources of Campylobacter jejuni, Salmonella spp., Listeria monocytogenes, and Shiga toxin-producing Escherichia coli (STEC), which might serve as reservoirs for transmission of pathogens. Samples were analyzed using mostly U.S. Food and Drug Administration's Bacteriological Analytical Manual protocols; however, Salmonella spp., L. monocytogenes and STEC were co-enriched in universal pre-enrichment broth. Campylobacter jejuni were enriched in Bolton broth containing Bolton broth supplement. Pathogens were isolated on agar media, typed biochemically, and confirmed using multiplex polymerase chain reaction protocols. Campylobacter jejuni, Salmonella spp., L. monocytogenes, Sorbitol-negative (SN)-STEC O157:H7, and sorbitol-positive (SP)-STEC, respectively, were isolated from 5.06%, 3.76%, 6.51%, 0.72%, and 17.3% of samples evaluated. Whereas other pathogens were isolated from all four farms, SN-STEC O157:H7 were isolated from only two farms. Diverse serotypes of SP-STEC including O157:H7, O26:H11, O111, and O103 were isolated. None of the five pathogen groups studied were isolated from bulk tank milk (BTM). Most pathogens (44.2%) were isolated directly from fecal samples. Bovine fecal samples, lagoon water, bedding, bird droppings, and rat intestinal contents constituted areas of major concern on dairy farms. Although in-line milk filters from two farms tested positive for Salmonella or L. monocytogenes, none of the pathogens were detected in the corresponding BTM samples. Good manure management practices, including control of feral animals, are critical in assuring dairy farm hygiene. Identification of on-farm pathogen reservoirs could aid with implementation of farm-specific pathogen reduction programs.     

生鸡肉中单核细胞增生李斯特菌的污染监测

目的：了解绍兴市部分农贸市场及超市的生鸡肉中单核细胞增生李斯特菌的污染状况。方法：监测农贸市场及超市的生鸡肉食品。结果：82份样品中检出Lm26株，总污染率为31．71％。其中农贸市场52份中检出Lm10株，总污染率为19．23％；超市30份中检出Lm16株，总污染率为53．33％。结论：大型超市生鸡肉中Lm检出率明显高于农贸市场。     

Isolation of Mycobacterium avium subspecies paratuberculosis from non-ruminant wildlife living in the sheds and on the pastures of Greek sheep and goats

This study aimed to: (1) investigate whether non-ruminant wildlife interfacing with dairy sheep and goats of four Greek flocks endemically infected with Mycobacterium avium subspecies paratuberculosis (MAP) harboured MAP and (2) genetically compare the strains isolated from the wildlife to those isolated from the small ruminants of these flocks. We cultured and screened, by polymerase chain reaction (PCR), pooled-tissue samples from 327 wild animals of 11 species for the MAP-specific IS900 insertion sequence. We also cultured faecal samples from 100 sheep or goats from each of the four flocks. MAP was detected in samples from 11 sheep, 12 goats, two mice, two rats, a hare and a fox. Only one rat had histopathological findings. Genetic typing categorized 21 isolates as cattle-type strains and two, from a house mouse and a goat respectively, as sheep-type strains; this is the first report of a rodent harbouring a sheep-type strain. The MAP types that were most frequently isolated amongst the sheep and goats of each flock were also the ones isolated from sympatric rodents; those isolated from the fox and hare also belonged to the predominant ruminant strains.     

重庆市万州区2010年-2011年流感病毒检测结果分析

目的:了解流感流行趋势及毒株变化情况,为制定流感防控策略提供科学依据。方法:利用实时荧光PCR法对流感监测标本进行流感病毒核酸检测,阳性标本进行病毒分离。结果:804份标本检出流感病毒核酸阳性168份;分离流感毒株57株。2010年流感高峰期发生在8月,以季甲H3型为优势毒株;2011年流感高峰期出现1月-3月,以新甲H1N1为优势毒株。流感患病率无性别差异,以5～年龄组流感病毒阳性率最高。结论:2010年-2011年万州区流感流行分别以季节性H3N2型、B-victoria系和新甲H1N1型为优势毒株。预防流感流行的重点人群是在校期间的中小学生。     

婴幼儿配方奶粉中阪崎肠杆菌分子检测方法探讨

目的：对婴幼儿配方奶粉中阪崎肠杆菌的分子检测方法进行探讨。方法：分别用常规PCR方法和实时荧光PCR方法对32份奶粉样品进行阪崎肠杆菌鉴定。结果：32份样品中检出2株阳性株,阳性率为6.25%,两种检测方法结果相符。结论：市售婴幼儿配方奶粉中存在阪崎肠杆菌污染,应尽快制订婴幼儿食品中阪崎肠杆菌的检测标准,分子检测方法可快速准确检测阪崎肠杆菌。     

广东国境口岸中央空调水嗜肺军团菌检测及结果分析

目的:为了解广东地区国境口岸中央空调冷凝水中军团菌的阳性率,分析军团菌对出入境旅客健康的潜在危害并为北京奥运会期间国境口岸军团菌防控提供理论依据。方法:通过对2007年度和2008年度广东地区6个国境口岸中央空调冷凝水的采集、处理,利用分离培养、乳胶凝集试验、血清学分型等方法对样本进行军团菌的检测及血清学分型,检验依据为ISO11731:1998。对检测结果进行分析。结果:2007年度从63份样本中检出军团菌7例,检测阳性率为11.1%,其中嗜肺军团菌4例;2008年度从46份样本中检出军团菌3例,检测阳性率为6.5%,全部为嗜肺军团菌。结论:本次军团菌检出率略低于有关文献报道的全国平均检出率,阳性样本中嗜肺军团菌L1型占比率较大(30%);本研究结果有利于分析国境口岸空调通风系统的卫生状况,为口岸卫生控制提供技术指导,有利于北京奥运会和谐、顺利举办。