温州市食品中沙门菌污染状况及特征分析

目的了解温州市食品中沙门菌的污染状况,分析分离的沙门菌血清型分布、耐药性及脉冲场凝胶电泳(PFGE)分子分型特征。方法依据GB 4789.4—2016《食品安全国家标准食品微生物学检验沙门氏菌检验》进行菌株分离鉴定及血清学分型,采用微量肉汤稀释法进行药敏试验,PFGE法进行分子分型。结果 6类食品2 039份样品中,37份样品检出沙门菌,检出率为1.8%,其中生禽肉和生畜肉检出率较高,分别为6.9%(20/290)和3.4%(10/290)。37株沙门菌分属16种血清型,居前三位分别为鼠伤寒沙门菌、德尔卑沙门菌和肠炎沙门菌。81.1%(30/37)的菌株对17种抗生素产生不同程度的耐药,呈现24种耐药谱,多重耐药率为56.8%(21/37)。PFGE图谱分为31种PFGE带型,呈多态性。结论沙门菌在温州市食品中存在一定的污染率,耐药情况形式严峻,PFGE图谱的聚集性与沙门菌的血清型有一定的联系,与耐药谱之间的关联性并不明确。     

2011—2012年山东淄博市肉鸡屠宰场沙门菌污染情况分析

目的 调查肉鸡屠宰场加工环节中沙门菌的污染状况。方法 采集肉鸡屠宰场的入厂活鸡肛拭子样本,宰杀褪毛后整禽样本、预冷后整禽样本、预冷池水、分割刀具和案板、冷冻鸡肉样本以及工人手涂抹样本,按《食源性致病菌监测工作手册》方法检测沙门菌。结果 2011—2012年共检测样品896份,检出沙门菌293株,检出率为32.7%;鸡胴体的检出率高于鸡活体。2011年沙门菌优势血清型为印第安纳沙门菌、鼠伤寒沙门菌和肠炎沙门菌,2012年优势血清型为印第安纳沙门菌、肠炎沙门菌。宰杀后样品中印第安纳沙门菌的构成比有所下降,而鼠伤寒、肠炎等其他优势血清型的构成比相对增加。结论 沙门菌广泛存在于屠宰场各环节样品中,宰杀环节易导致沙门菌的交叉污染。     

肉猪养殖和屠宰环节沙门菌污染状况监测分析

目的 了解开封市肉猪养殖屠宰加工过程中沙门菌的污染状况.方法 采集不同来源的养殖场猪混合粪便、成年猪肛拭子、胴体涂抹物、肠系膜淋巴结样本,共187份,按照GB 4789.4-2010进行沙门菌的分离和鉴定.结果 猪混合粪便沙门菌检出率为4.5％,肛拭子沙门菌的检出率为16.4％,胴体涂抹物沙门菌检出率为34.5％,肠系膜淋巴结沙门菌检出率为27.3％.不同季节的检出率差异有统计学意义(P＜0.05).阳性分离株分布于沙门菌的5个群,共14个血清型,以阿贡纳沙门菌和德尔卑沙门菌为主.结论 屠宰环节是沙门菌交叉污染的关键点,应采取综合措施,有效控制猪肉沙门菌污染.     

2013—2016年泉州市感染性腹泻病例中沙门菌血清学鉴定及耐药性分析

目的 分析2013—2016年泉州市食源性疾病监测哨点医院感染性腹泻病例中沙门菌的血清型及细菌耐药性,为临床合理用药提供参考。方法 对送检的腹泻患者标本进行沙门菌增菌培养和分离鉴定,采用传统玻片凝集法和液相悬浮芯片技术(xMAP)法进行血清学分型,微量肉汤稀释法进行药敏试验,用Excel软件处理数据。结果 460份标本中有73份检出沙门菌,共分离到沙门菌73株(15.87%),检出11个血清型,主要血清型为圣保罗沙门菌(42.47%,31/73)、阿雷查瓦莱塔沙门菌(16.44%,12/73)和布利丹沙门菌(12.33%,9/73)。玻片凝集法检出61株(83.56%,61/73)完整血清型,12株不确定血清型,液相悬浮芯片技术法确定了71株(97.26%,71/73)完整血清型,仅2株未确定。药敏试验显示沙门菌对头孢唑林、头孢替坦和妥布霉素3种抗生素的耐药率高达100.00%(73/73),其次为阿米卡星(95.89%,70/73)和庆大霉素(84.93%,62/73),对厄他培南、环丙沙星、左氧氟沙星、呋喃妥英这4种抗生素不具有耐药性。结论 泉州市感染性腹泻病例中沙门菌已对多种抗生素产生较高的耐药性,临床上应及时了解沙门菌的血清型分布及其耐药情况,合理选择抗菌药物。     

2003-2010年山东省食源性沙门菌血清分型及药敏分析

目的了解2003—2010年山东省食源性沙门菌的血清型分布及耐药情况,为制定政策提供科学依据。方法根据GB/T 4789—2008《食品卫生微生物学检验》方法进行沙门菌菌种鉴定和血清分型;采用临床实验室标准研究所(CLSI)推荐的微量肉汤稀释法进行药物敏感性试验和结果判读,确定耐药表型。结果 120株确定血清型沙门菌分属5个群(8个亚群)24个血清型,肠炎和德比沙门菌为最常见血清型。胥瓦增格隆、维也纳、布里丹、明斯特、乌赫利等9种血清型为2010年首次检出血清型。126株沙门菌对14种抗生素均有不同程度的耐药,萘啶酮酸的耐药率最高(61.90%),其次为四环素(33.33%)、氨苄青霉素(31.75%)、磺胺嘧啶(26.19%);而敏感性以头孢吡肟最高(5.37%),其次是阿米卡星(9.52%)、环丙沙星(10.32%)。结论山东省食源性沙门菌耐药形势严峻,应加强畜牧养殖业中抗生素使用的管理,从食物链的源头和动物食品生产过程中采取合理的干预措施,保障食品安全。     

2010—2012年新疆乌鲁木齐地区零售生肉中沙门菌污染情况调查

通过对2010—2012年新疆乌鲁木齐地区零售生肉中沙门菌的检测分析,了解沙门菌污染情况,掌握乌鲁木齐地区零售肉品中沙门菌污染动态变化。方法 按照沙门菌检验国家标准GB/T 4789.1—2010对乌鲁木齐地区的零售肉(鸡肉、羊肉、牛肉、猪肉)检测分离沙门菌并进行血清型分型。结果 2010—2012年共检测1406份零售生肉样品,生鸡肉的感染率达到9.14%,生猪肉为9.06%,生羊肉为8.05%,生牛肉为6.44%,检测共分离得到123株沙门菌,经血清型鉴定可以分为4个血清群,7种血清型,分别为肠炎沙门菌(n=17)、萨奥沙门菌(n=9)、塔西沙门菌(n=8)、乌干达沙门菌(n=6)、康科德沙门菌(n=3)、汤姆逊沙门菌(n=3)和德尔卑沙门菌(n=2),未定型沙门菌75株。结论 新疆乌鲁木齐地区零售肉类中存在沙门菌污染,沙门菌菌株为不同的表型,地区内生肉品中沙门菌污染不容忽视,需要加强对零售肉市场的卫生检疫,防控沙门菌病。     

2010年江苏省肉鸡沙门菌污染专项监测分析

目的了解肉鸡养殖和屠宰过程中沙门菌的污染状况,为确定从生产到销售各环节沙门菌分布和疾病可能传染源、制定公共卫生措施并评价其有效性提供科学依据。方法按照《全国食源性致病菌监测工作手册》中专项监测的采样和实验室检测要求,2010年共采集活体肉鸡肛拭样本210份,胴体样本204份,监测沙门菌污染情况。结果肛拭样本检出沙门菌23份,检出率10.95%;胴体样本检出沙门菌71份,检出率34.80%。两类样本的血清学分型构成比不同(χ2=15.7,P<0.001),肛拭样本检出的23株沙门菌中有22株印第安纳沙门菌,胴体样本中检出的71株沙门菌中有35株为印第安纳沙门菌,22株为奥尔巴尼沙门菌。结论肉鸡活体肛拭和胴体样本沙门菌检出率差异有统计学意义(χ2=33.5,P<0.001),胴体高于活体检出率,活体和胴体的沙门菌来源不同,胴体可能存在交叉污染。     

中国鸡肉沙门菌厨房内交叉污染模型初探

目的探索适用于我国食品微生物风险评估的鸡肉沙门菌厨房内交叉污染模型。方法开展我国部分居民厨房内鸡肉烹调加工行为调查,构建厨房内交叉污染的矩阵模型和简化模型。结果我国居民报告的案板生熟分开率为31.2%(78/250);矩阵模型中影响交叉污染发生的因素(Spearman相关系数)为加工凉菜先于加工鸡肉(0.925)、加工前鸡肉中沙门菌污染量(0.135)、更换案板(0.106)、洗手方式(-0.088)和洗案板方式(-0.064);矩阵模型与简化模型推算的凉菜中沙门菌的污染量和发病风险相近,影响交叉污染的关键因素相同;矩阵模型和简化模型推算的交叉污染后沙门菌的平均转移率分别是0.35%(95%CI:0.32~0.38)和0.18%(95%CI:0.16~0.20)。结论本研究构建的模型适用于我国厨房内鸡肉沙门菌交叉污染研究。     

济南市肉鸡生产链沙门菌污染监测及分析

了解肉鸡孵化、养殖、屠宰加工和配送分销各环节的沙门菌污染状况,确定易受污染的环节和样品类别,为预防和控制由沙门菌引起的食源性疾病提供科学依据。方法 按照随机抽样的原则,在济南市肉鸡孵化场、养殖场、屠宰场(点)和配送分销点设置16个监测点,按不同的季节和环节定期随机采集监测样本。检验方法按照《2012年全国食源性致病菌监测工作手册》执行。结果 监测17种样品共1204份,13种样品检出沙门菌202株,总检出率为16.78%。除1种不可分型外,其他分属4群28种血清型,以印第安纳血清型沙门菌最多(37.13%)；4个环节中,以屠宰加工环节沙门菌检出率最高(23.14%)；四个季度中,以第二季度沙门菌检出率最高(21.74%)；17种样品中,以屠宰环节的褪毛后整禽样本沙门菌检出率最高(42.19%)。结论 济南市肉鸡相关行业的沙门菌交叉污染严重,应加强肉鸡生产链全过程的监管和监测,并针对各污染环节和工序,确定不同的关键控制点,制定相应的操作程序,以减少沙门菌的交叉污染。     

陕西省某活鸡屠宰场肉鸡相关样品中沙门菌定量检测及污染分析

目的了解肉鸡屠宰加工中不同时间和环节沙门菌的污染情况,分析污染关键点。方法 2016年11月至2017年11月从陕西省某活鸡屠宰场不同环节定期采集活鸡肛拭子标本、整鸡胴体和鸡肉样品,使用最大可能数(MPN)法对沙门菌进行定量检测,同时分离菌株;采用聚合酶链式反应(PCR)技术对沙门菌进行鉴定,同时结合血清凝集技术对沙门菌鉴定结果进行确认。结果采集的284份样品中有67份检出沙门菌,检出率为23. 6%,平均MPN值为0. 051 6 MPN/g。2017年7月采集的样品沙门菌污染最为严重,检出率为37. 8%(14/37),平均MPN值为0. 064 7 MPN/g; 2016年11月检出率最低,为13. 9%(5/36),平均MPN值为0. 043 6 MPN/g。不同屠宰环节中,浸烫褪毛后整鸡胴体样品中沙门菌检出率最高(43. 3%,26/60),平均MPN值为0. 060 5 MPN/g;分割后冷冻前鸡胸脯肉样品中沙门菌检出率最低(18. 3%,11/60),平均MPN值为0. 036 8 MPN/g,略高于储存配送过程整鸡胴体/鸡胸脯肉样品中沙门菌的污染水平(0. 035 8 MPN/g)。结论活鸡屠宰过程沙门菌的检出率与MPN值具有较强的季节性,在不同屠宰加工环节存在纵向和交叉污染,应对活鸡屠宰加工过程沙门菌污染严重的环节进行重点控制。     

肉鸡加工过程中沙门氏菌的污染监测及分析

目的对肉鸡屠宰加工的不同环节进行沙门氏菌监测,了解各个环节沙门氏菌的污染状况,分析肉鸡加工过程中沙门氏菌的污染来源及关键环节。方法选择河南省某大型肉鸡屠宰加工企业作为监测点,在肉鸡屠宰前、褪毛后、过预冷池后、被分割后和包装入库等环节及预冷池水、分割刀具案板和工人手等处分别采集样本,共计1756份,进行沙门氏菌检测及其血清型鉴定。结果于1756份样本中检出沙门氏菌阳性样本700份,检出率为39.9%。其中,褪毛后整禽的沙门氏菌检出率最高,达63.9%;其次为过预冷池后的整禽胴体,检出率为57.3%。屠宰加工环节中检出的沙门氏菌中肠炎沙门氏菌最多,占71.7%,其次为印第安纳沙门氏菌,占20.8%。结论肉鸡在养殖期间存在沙门氏菌污染,且在屠宰加工环节存在交叉污染,应针对相关环节进行重点控制和工艺改进。     

2016年河南省市售生禽肉中沙门菌血清分型和分子分型研究

目的 了解河南省市售生禽肉中沙门菌污染状况,并对分离株进行血清型和分子分型研究,为河南省食源性疾病溯源数据库提供基础数据。方法 沙门菌检测及血清分型、脉冲场凝胶电泳(PFGE)分子分型分析参照国家食品及食源性疾病监测网工作手册。结果 165份生禽肉样品中检出41株沙门菌,分属13个血清型,优势血清型是科瓦利斯沙门菌、肯塔基沙门菌、鼠伤寒沙门菌及达布沙门菌。经Xba I酶切,获得30种带型,每种带型包括1～5株菌株,相似度为47.5%～100%。部分不同血清型沙门菌PFGE型相似。结论 河南省市售生禽肉沙门菌污染严重,沙门菌血清型和基因型呈现多样化,基因型有一定的地区聚集性。     

Interventions to control Salmonella contamination during poultry,cattle and pig slaughter

The fundamental principle of controlling microbial contamination during slaughter is based on sanitary and hygienic processes. Both choosing abattoir technologies and conducting individual operations should be approached with the primary goal of minimizing microbial load on the final product. Nevertheless, even when best hygienic abattoir practices are applied, complete prevention of all microbial contamination of carcasses is unachievable under commercial conditions. Therefore, in some situations it may be considered necessary to further reduce the microbial loads on carcasses through application of additional control interventions, i.e. decontamination treatments. Treatments applied on poultry carcasses or parts include water, steam and chemical solutions (e.g., lactic or acetic acid, chlorine-based compounds, cetylpyridinium chloride, and trisodium phosphate) and result in overall microbial reductions of 0.6–3.8 log units; antimicrobial activity of some chemicals (e.g., chlorine compounds) is reduced in the presence of organic material. Decontamination treatments of hides (pre-skinning) and/or cattle carcasses reduce Salmonella by < 0.7–5.1 log units. Salmonella prevalence reductions achievable by decontamination of porcine carcasses seem to be at least two-fold. Overall Salmonella reductions on final carcasses and meat can be significantly improved when multiple decontamination treatments are applied sequentially during slaughter and dressing operations. It is important to note that decontamination interventions should be validated and considered as part of a hazard analysis critical control points (HACCP)-based food safety system which is subject to verification and auditing, and they should never be used as a substitute for good sanitation and proper hygiene practices.     

肉鸡饲养加工过程中沙门菌污染环节的探讨与分析

目的 探讨开封市肉鸡从孵化、养殖,到屠宰、加工、运输和销售各环节样品沙门菌污染状况.方法 采集2012年4个季度开封地区种鸡养殖场、肉鸡孵化场、养殖场、屠宰场和大型超市中土壤、饲料、鸡粪、鸡肉、屠宰工具、工人手等18个环节共802份样品.按照GB 4789.4-2010进行沙门菌鉴定和血清学分型,用SPSS 17.0软件对数据进行统计分析.结果 脱毛池水中沙门菌检出率最高为75％,其次成鸡粪便、鸡肉、刀具案板、肛拭子中沙门菌检出率分别为58.3％、49.4％、33.3％、5.6％,鸡胚和运输车辆中未检出沙门菌.本研究共检出6个血清型,以肠炎沙门菌和印第安纳沙门菌检出率最高;第二季度沙门菌菌型数最多.结论 鸡肉屠宰加工过程使沙门菌污染扩大,脱毛机及脱毛池水是沙门菌交叉污染的关键点,不同季节的检出率差异无统计学意义(P＞0.05).     

2020年福建省生禽肉中沙门菌污染状况及病原学特征分析

目的 了解2020年福建省生禽肉中沙门菌污染状况、血清分型和耐药情况。方法 采集2020年福建省生禽肉样品178份,按照GB 4789.4—2016的方法分离出沙门菌后进行血清分型,并对分离出来的沙门菌进行药敏实验。结果 共检出沙门菌40株,检出率为22.5%(40/178),通过血清分型,鼠伤寒沙门菌占比最高,检出率为22.5%(9/40),其次分别是肯塔基沙门菌和肠炎沙门菌,检出率分别为17.5%(7/40)、15.0%(6/40)。药敏实验结果表明,40株沙门菌对四环素耐药程度最高,耐药率为77.5%(31/40),其次是萘啶酸和氨苄西林,耐药率分别为62.5%(25/40)、52.5%(21/40)。多重耐药率(MDR＞3)为52.5%(21/40)。结论 2020年福建省生禽肉中存在一定程度沙门菌污染,以鼠伤寒沙门菌为主。菌株耐药状况严重,且存在较高的多重耐药率,应加强食品安全风险监测,预防食源性疾病暴发。     

An approach for mapping the number and distribution of Salmonella contamination on the poultry carcass

Mapping the number and distribution of Salmonella on poultry carcasses will help guide better design of processing procedures to reduce or eliminate this human pathogen from poultry. A selective plating media with multiple antibiotics (xylose-lysine agar medium [XL] containing N-(2-hydroxyethyl)piperazine-N'-(2-ethanesulfonic acid) and the antibiotics chloramphenicol, ampicillin, tetracycline, and streptomycin [XLH-CATS]) and a multiple-antibiotic-resistant strain (ATCC 700408) of Salmonella Typhimurium definitive phage type 104 (DT104) were used to develop an enumeration method for mapping the number and distribution of Salmonella Typhimurium DT104 on the carcasses of young chickens in the Cornish game hen class. The enumeration method was based on the concept that the time to detection by drop plating on XLH-CATS during incubation of whole chicken parts in buffered peptone water would be inversely related to the initial log number (N0) of Salmonella Typhimurium DT104 on the chicken part. The sampling plan for mapping involved dividing the chicken into 12 parts, which ranged in average size from 36 to 80 g. To develop the enumeration method, whole parts were spot inoculated with 0 to 6 log Salmonella Typhimurium DT104, incubated in 300 ml of buffered peptone water, and detected on XLH-CATS by drop plating. An inverse relationship between detection time on XLH-CATS and N0 was found (r = -0.984). The standard curve was similar for the individual chicken parts and therefore, a single standard curve for all 12 chicken parts was developed. The final standard curve, which contained a 95% prediction interval for providing stochastic results for N0, had high goodness of fit (r2 = 0.968) and was N0 (log) = 7.78 +/- 0.61 - (0.995 x detention time). Ninety-five percent of N0 were within +/- 0.61 log of the standard curve. The enumeration method and sampling plan will be used in future studies to map changes in the number and distribution of Salmonella on carcasses of young chickens fed the DT104 strain used in standard curve development and subjected to different processing procedures.     

Survey of Salmonella and Campylobacter contamination of whole, raw poultry on retail sale in Wales in 2003

A survey of the Salmonella and Campylobacter contamination of raw, whole chickens available to consumers in Wales was performed between March and December 2003. In total, 736 samples were taken, and overall contamination rates of 73.1% for Campylobacter and 5.7% for Salmonella were found. This survey follows a survey performed during 2001 to 2002 by Welsh local authorities and the National Public Health Service for Wales that established updated baseline rates for both pathogens in raw, whole chicken available to consumers in Wales. This survey indicated no difference in Campylobacter rates between fresh and frozen samples or between samples taken from retailers and local butchers, but significant differences existed in Salmonella rates between fresh and frozen samples and between those sampled from retailers and butchers, with frozen chickens and samples taken from retailers having significantly higher rates. However, the difference in Salmonella isolation rate between retailers and butchers was found to be due to the differences in the proportions of fresh and frozen chickens sampled from these locations, with a significantly higher number of frozen chickens (with a higher Salmonella rate) being sampled from retailers.     

食源性沙门氏菌鉴定和血清分型能力验证

目的验证本实验室在国家食品安全风险监项目中微生物检验能力和实验室质量控制水平。方法实验样品按照考核方作业指导书要求进行样品前处理后,参照GB 4789.4-2016《食品安全国家标准食品微生物学沙门氏菌检验》进行沙门氏菌检验,同时取增菌液与预增菌液使用全自动病原微生物检测系统进行鉴定。将全自动病原微生物检测系统鉴定结果与生化试验相结合进行对比,结果均符合沙门氏菌属的样品再进行血清学鉴定。结果编号2017S-16(3)-1样品检出鼠伤寒沙门氏菌,2017S-16(3)-2样品检出阿贡纳沙门氏菌,2017S-16(3)-3样品未检出沙门氏菌。本实验室顺利完成考核,结果与考核方一致。结论本实验室通过参加能力验证和质控考核,提升食品检验机构检验能力和实验室质控水平。     

沙门氏菌的血清分型及分子鉴定研究进展

沙门氏菌(Salmonella)是常见的食源性致病菌,该菌属型别繁多。沙门氏菌血清型的划分对菌株的分类与鉴定有着重要的意义。本文主要介绍了沙门氏菌的O抗原、H抗原和Vi抗原的特性及结构特征,阐述了多种分子鉴定方法在血清分型检测中应用的进展情况,这些方法大多是以PCR为基础建立的,如多重PCR、基因芯片、高分辨率熔解曲线技术等,使用的引物是根据沙门氏菌的O抗原、H抗原和Vi抗原的编码基因设计的。此外,本文还介绍了两种高通量鉴定方法,通用探针沙门氏菌血清分型法和PremiTest沙门氏菌分型法,但是这两种方法的探针设计比较复杂,使用的设备较为特殊,不易推广。环介导等温扩增(LAMP)方法是等温扩增方法之一,虽然简单、快速、灵敏,但是只适合于单一血清组或血清型的检测。     

Diversity of Salmonella isolates using serotyping and multilocus sequence typing

One hundred and twenty-one Salmonella isolates were obtained from food, feed, and live chicken samples derived from 13 countries or regions. In this study, their subtypes were evaluated by serotyping and multilocus sequence typing (MLST), and their genetic profiles were also characterized. It was demonstrated by serotyping on these isolates that 36 various serovars were obtained in this study, of which three serotypes S. Babelsberg, S. Fresno, and S. II were first found in mainland China. Based on Simpson’s index of diversity, the serotyping method had a 0.943 discriminatory power. Meanwhile, there were a total of 42 unique sequence types (STs) characterized by MLST, and the discriminatory power of MLST (D = 0.947) was close to that of the serotyping method. In MLST, hisD revealed the highest levels of nucleotide diversity. In addition, ST-92 was the most common ST represented by 16 Salmonella isolates, followed by ST-367 which was represented by 14 isolates. Seven new alleles were identified, which were associated with other alleles and resulted in the assignment of nine new STs. It was concluded from the results that MLST was generally associated with serotype, but not associated with the epidemiological source of the samples, and antimicrobial resistance patterns.