山东省鸡源空肠弯曲菌喹诺酮类药物耐药机制研究

通过对采集于山东省肉鸡屠宰场的202株空肠弯曲菌进行喹诺酮类耐药分子机制的研究,包括7种可以移动耐药基因筛查,喹诺酮耐药决定区(QRDR)突变检测和parC的筛查,确定了我国山东省鸡源空肠弯曲菌对喹诺酮类药物的耐药表型主要为gyrA中QRDR C-257-T突变所造成.并发现在空弯中存在于gyrA和gyrB基因上的部分沉默突变有着地域流行性特点.这些观察结果为解释我国食品动物源空肠弯曲菌耐药性现状,防控耐药空肠弯曲菌传播和流行提供基础数据.     

湖南省规模化猪场猪源大肠杆菌的耐药性调查

抗菌药物在养殖业的广泛使用引起了动物源细菌耐药性的日益加重与广泛传播。动物源细菌耐药性的流行不仅加大畜禽疫病的防控难度,给养殖业造成巨大损失,而且动物源耐药菌还可通过食物链感染人体或将耐药基因转移至人体病原菌,给食品安全和     

动物源细菌耐药性监测与流行病学研究

全面分析了开展动物源细菌耐药性监测与流行病学研究的必要性和紧迫性,介绍了动物源细菌耐药性监测与流行病学研究的国外概况和国内现状,指出当前我国在该领域内存在的问题,提出6点建议以期做好动物源细菌耐药性的防控工作。     

中美动物源微生物耐药性监测对比研究

抗微生物药物在保障动物健康和食品安全方面发挥了重要作用,为了应对日益严峻的微生物耐药性问题,动物源微生物耐药性监测是应对微生物耐药性风险的重要防控策略。在“同一健康体系”工作框架下,中国和美国积极进行动物源微生物耐药性监测。本文通过对比研究中美动物源微生物耐药性系统的监测设计、监测对象和监测数据应用情况,结合我国畜牧兽医行业现状,立足我国动物源微生物耐药性监测客观需求,旨在为我国动物源微生物耐药性监测工作提供参考。     

四川省动物源常见细菌耐药性现状

近年来由于兽用抗生素的大量使用,动物源尤其是食品动物中常见病原菌耐药性水平逐渐增高,并可在人、动物和环境中传播。尽管国内外已有动物源细菌耐药菌株的大量报道,但是聚焦局部地区仍缺少系统的总结。因此,论文针对四川地区动物源常见的大肠埃希氏菌、沙门氏菌和肠球菌的耐药性进行总结,介绍以上3种细菌的耐药水平、分布及重要耐药基因的传播特征,以期为公共卫生安全提供预警,为省级层面开展动物源细菌耐药性监测提供基础数据。     

我国动物源细菌耐药性数据库的建立与应用

为加强全国动物源细菌耐药性监测数据统一管理,实时掌握我国动物源细菌耐药性的流行动态,中国兽医药品监察所联合多家国内细菌耐药性监测单位,开发了我国的动物源细菌耐药性监测数据库。该数据库为B/S架构,全国不同地区动物源细菌耐药性监测实验室均可通过网页浏览器连接服务器,实现了监测数据即时储存、统计分析和上报,为我国兽医临床细菌耐药性监测提供了重要的技术支持。     

农业部印发通知要求加强动物源细菌耐药性监测工作

正为贯彻落实《遏制细菌耐药性国家行动计划(2016年~2020年)》,进一步加强动物源细菌耐药性监测工作,保证动物源性食品安全和公共卫生安全,农业部近日发布了关于印发《2017年动物源细菌耐药性监测计划》的通知。通知对动物源细菌耐药性监测工作任务分工作了规定。农业部负责组织全国动物源细菌耐药性监测工作。各省(自治区、直辖市)兽医行政管理部门负责选定连续定点监测养殖场(猪场、肉鸡场、蛋鸡场或奶牛场各1个,共3个),     

我国动物源细菌耐药性监测及预警的研究进展

利用调查和数据统计报道我国近年来的兽用抗生素使用、养殖业用药背景、抗菌药物耐药、动物源细菌耐药性监测、动物源细菌耐药监测数据库研究及国家制定的相关政策等现状,并针对我国动物源细菌的耐药和监测现状,提出了我国政府与各地区相关部门应科学评估分析动物源细菌耐药性监测数据及变化趋势;借鉴发达国家的经验和方法,完善我国动物源细菌耐药性监测网络和监测体系;加强教育和宣传等应对措施,为解决全球动物源细菌耐药性问题作出贡献。     

库尔勒市牛源空肠弯曲菌的分离鉴定及耐药性分析

了解库尔勒市牛源空肠弯曲菌流行及耐药性状况,为空肠弯曲菌的防控与临床用药提供理论基础。采用特异性选择培养基培养并结合PCR法对新疆库尔勒市及其周边牛养殖场采集的787份肛拭子样品进行空肠弯曲菌的分离鉴定,并采用纸片扩散法对牛源空肠弯曲菌分离株进行10类23种抗菌药物的耐药性检测。结果共分离到空肠弯曲菌38株,总分离率为4.83%(38/787); 38株空肠弯曲菌对克林霉素、四环素、氨苄西林、林可霉素、阿莫西林、头孢噻肟、头孢曲松表现高度耐药,耐药率均达80%以上;对美罗培南的敏感性最高,耐药率为0。研究表明,库尔勒市存在牛源空肠弯曲菌的流行隐患,空肠弯曲菌分离株对不同药物的耐药性存在差异,且耐药谱具有多样性,多重耐药情况普遍,应引起各部门的高度重视。     

一个值得高度关注的问题——动物源细菌耐药性

由于动物源细菌耐药性关乎到人类健康,使得畜禽疾病防控和公共卫生安全日益受到全世界的普遍关注。本文就动物源细菌耐药性的危害、我国动物源细菌的耐药性状况、发展趋势及应对策略进行了综述,以期对我国开展动物源细菌耐药性检测和制定预防对策提供参考。     

Fluoroquinolone-resistant Campylobacter in animal reservoirs: dynamics of development, resistance mechanisms and ecological fitness

Thermophilic Campylobacter species, including Campylobacter jejuni and Campylobacter coli, are responsible for foodborne campylobacteriosis in humans and are increasingly resistant to fluoroquinolone (FQ) antimicrobials. The therapeutic use of FQ antimicrobial agents in food animal production, particularly in poultry, has become a concern for public health, because the practice may promote the emergence of FQ-resistant Campylobacter that can be transmitted to humans through the food chain. Recent studies have indicated that Campylobacter displays a hypermutable phenotype in response to in vivo treatment with FQ antimicrobials, resulting in the rapid emergence of resistant mutants. Distinct from other Gram-negative bacteria, the acquisition of FQ resistance in Campylobacter does not require stepwise accumulation of gyrA mutations and overexpression of efflux pumps, and is mainly mediated by single-step point mutations in gyrA in the presence of a constitutively expressed multidrug efflux pump, CmeABC. The simplicity of the resistance mechanisms may facilitate the rapid adaptation of Campylobacter to FQ treatment. The FQ-resistant Campylobacter mutants derived from chickens do not show a fitness cost in vivo and are ecologically competitive in the colonization of chickens even in the absence of antimicrobial selection pressure. These findings suggest that FQ-resistant Campylobacter may continue to persist regardless of antimicrobial usage, and highlight the need for extra effort to prevent the occurrence and spread of FQ-resistant Campylobacter in animal reservoirs.     

Antimicrobial resistance of thermophilic Campylobacter spp. isolated from cattle in Poland

Campylobacter species are among the most frequently identified bacterial causes of human gastroenteritis. Because Campylobacter spp. harbored by cattle can be transmitted to humans, in this study we investigated antimicrobial resistance of thermophilic Campylobacter isolated from cows. Our study included 150 strains of Campylobacter (143 strains of C. jejuni and 7 strains of C. coli) isolated from cows in South-Western Poland. The minimal inhibitory concentration (MIC) to ciprofloxacin, erythromycin, gentamicin and tetracycline were determined using the agar dilution methodology. All strains of C. coli were susceptible to all four drugs studied. The most frequently detected resistance of C. jejuni was to ciprofloxacin (26 strains 18.2%). Resistance to tetracycline was observed in 5 strains (3.5%). All strains of C. jejuni were susceptible to erythromycin and gentamicin.     

Antimicrobial susceptibility patterns of thermotolerant Campylobacter strains isolated from food animals in Ethiopia

Thermotolerant Campylobacter spp. are frequent causes of diarrhoea in humans worldwide mostly originating from poultry. It has been suggested that extensive veterinary use of antibiotics is largely responsible for resistance in human isolates. During a 4-month period from January to April 2004, 192 Campylobacter spp. were isolated from fecal samples of 485 healthy food animals. The in vitro susceptibility to 12 antibiotics was determined by the agar disk diffusion method. Among the 192 Campylobacter spp. isolated, 135 (70.3%) were identified to be C. jejuni, 51 (26.6%) were C. coli and 6 (3.1%) were C. lari. C. jejuni was the most prevalent species in chickens (80.8%) versus 16.2% C. coli and 3.0% C. lari. All isolates found in pigs were C. coli. All strains were sensitive to chloramphenicol and ciprofloxacin and all were resistant to cephalothin. More than 90% of the strains were sensitive to clindamycin, erythromycin, gentamicin, nalidixic acid, norfloxacin, streptomycin and tetracycline. Resistance was found against ampicillin in 20% and trimethoprim-sulphamethoxazole in 37.5%. Resistance was not statistically different among C. jejuni, C. coli and C. lari (p>0.05). Multidrug resistance to two or more drugs was detected in 14.5% of strains. In conclusion, the study showed that antimicrobial resistance is found only at relatively low frequencies for most antimicrobial agents tested except for ampicillin and trimethoprim-sulphamethoxazole. The low percentages of resistance to most antimicrobial agents tested in this study may be the result of low/no usage of these agents as a growth promoters or treatment in the Ethiopian animal farm setting. The detection of multidrug resistant isolates may pose a threat to humans and further limits therapeutic options.     

Antimicrobial susceptibility in thermophilic Campylobacter species isolated from pigs and chickens in South Africa

Campylobacter jejuni is one of the leading causes of sporadic food-borne bacterial disease in humans. In intensive poultry and pig rearing systems the use of oral antibiotics is essential to maintain health. Consequently, there is a high risk for the thermophilic Campylobacter jejuni and C. coli resident in the intestinal tract of food animals to develop resistance to commonly used antibiotics. Contamination of meat or eggs with pathogenic strains of resistant Campylobacter could, therefore, result in a form of campylobacteriosis in humans that is difficult to treat. The aim of this investigation was to determine the antimicrobial susceptibility of thermophilic Campylobacter spp. isolated from pigs and poultry by the broth microdilution minimum inhibitory concentration (MIC) test. A total of 482 samples from the Western Cape and Gauteng provinces was collected and analysed. Thirty-eight Campylobacter isolates were obtained. Analysis of data revealed that C. jejuni strains mainly of poultry origin were more resistant to the fluoroquinolones, macrolides and tetracyclines and the C. coli strains were more resistant to the macrolides and lincosamides. Multi-resistance was also detected in 4 Campylobacter strains from the Western Cape. With the exception of tetracyclines, strains from high health Gauteng broiler farms were susceptible to antibiotics used to treat Campylobacter infections.     

Poultry meat as a source of human campylobacteriosis

Campylobacteriosis is a prevalent diarrhoeal illness in humans, and poultry meat is considered the most important source of foodborne infection with Campylobacter spp. In this review, the disease burden of campylobacteriosis, the most important risk factors for Campylobacter colonization in broilers, and potential interventions to reduce poultry-related human exposure to Campylobacter spp. are discussed.     

Increase of bacterial resistance in human medicine by resistance genes of bacteria from meat supplying animals

Two different groups of bacteria carrying genes encoding for resistance to antibiotics may be transmitted from animals to humans via food products: a.) obligate infectious agents (enteric pathogens, e.g. Salmonella enterica spp., Campylobacter spp., EHEC) and b) facultative pathogenic species (e.g. E. coli, enterococci). Thus far, it is unknown whether genes encoding for resistance to antibiotics from these bacteria may be transferred to bacteria in normal flora of the host. The transfers of genes encoding for resistance to vancomycin from animal sources to the mucosa of humans has been suggested. Thus, there is a threat that these plasmid-encoded resistance genes may also be transferred to other gram-positive organisms present in the human flora. Vancomycin is the antibiotic in reserve for treatment of infections caused by oxacillin (methicillin) resistant strains of S. aureus and by strains of pneumococcus resistant to penicillin.     

A survey of Salmonella spp and Campylobacter spp in dairy goat faeces and bulk tank milk in the Murcia region of Spain

This study was designed to investigate the occurrence of Salmonella spp and Campylobacter spp in faeces samples from 222 healthy Murciano-Granadina dairy goats reared on 12 farms in Spain and in samples of bulk tank milk from 11 of those herds. Neither Salmonella spp nor Campylobacter spp were isolated from any of the samples. Our results suggest that, under the management practices applied to this breed in Spain, Murciano-Granadina goats are not likely to be a significant reservoir for these food-borne pathogens.     

Distribution and genetic variability among Campylobacter spp. isolates from different animal species and humans in Switzerland

In Switzerland, a national database with 1028 Campylobacter isolates from poultry, pigs, cats, dogs, cattle, humans, zoo animals and water has been created. The database contains the genetic fingerprint and background information of each Campylobacter isolate. Dominant species could be identified in the different sources with a majority of Campylobacter jejuni in poultry (73%), humans (79%), cattle (95%), zoo animals (40%) and water (100%), of Campylobacter coli in pigs (72%), and of Campylobacter upsaliensis/helveticus in cats and dogs (55%). The comparison of three genotyping methods, amplified fragment length polymorphism (AFLP), pulsed field gel electrophoresis and restriction fragment length polymorphism, revealed that AFLP allows discrimination between the different Campylobacter species and is the most appropriate method to distinguish specific strains within the same species. Genotyping analysis demonstrated that the Campylobacter population is heterogeneous among the different sources and that no dominant clone is spread in the country. Genotyping and the resulting database are useful tools to trace back future Campylobacter infections.     

禽源空肠弯曲杆菌的分离鉴定及其致病性的初步研究

本研究对广东部分地区不同品种家禽空肠弯曲杆菌的流行状况进行了调查。通过菌落和菌体形态、生化特征、培养特性等生物学特性和多重PCR方法对所分离菌株进行鉴定,结果表明广东地区鸡、鸭和鹅空肠弯曲杆菌的带菌率分别为7.93%、2.46%和4.16%。从分离株中选取10株进行了致病性试验,结果表明禽源空肠弯曲杆菌对雏鸡的主要病理变化是腹泻便血,肝脏出现白色坏死灶,盲肠充血、膨大充满气泡和红色内容物。     

家禽养殖环节弯曲菌分布特点

弯曲菌是世界范围内引起人细菌性胃肠炎的主要病原菌,近年来由其引起的弯曲菌病发生率呈指数增长趋势,而家禽作为弯曲菌的天然宿主是人类弯曲菌病的主要来源。论文针对家禽养殖环节,对鸡群中弯曲菌的流行状况、耐药性及鸡群中弯曲菌来源等方面的研究进展进行分析,以期为家禽养殖环节弯曲菌的防控措施制定提供参考。