Prevalence of Campylobacter spp. in poultry and poultry meat in Germany

Of 509 samples from poultry flocks, 209 isolates (41.1%) were Campylobacter positive. The number of positive cases in broiler carcasses was 45.9%. Of 52 pheasants investigated, 25.9% were Campylobacter positive. Campylobacter jejuni was isolated from 86 (42.0%) poultry flock samples, 47 (43%) broiler samples and 15 (28%) wild pheasant samples. C. coli was found at a rate of 1.2% in poultry flocks, 13% in broilers and 21% in pheasants.     

Risk based microbiological criteria for Campylobacter in broiler meat in the European Union

Quantitative microbiological risk assessment (QMRA) allows evaluating the public health impact of food safety targets to support the control of foodborne pathogens. We estimate the risk reduction of setting microbiological criteria (MCs) for Campylobacter on broiler meat in 25 European countries, applying quantitative data from the 2008 EU baseline survey. We demonstrate that risk based MCs can be derived without explicit consideration of Food Safety Objectives or Performance Objectives. Published QMRA models for the consumer phase and dose response provide a relation between Campylobacter concentration on skin samples and the attending probability of illness for the consumer. Probabilistic modelling is used to evaluate a set of potential MCs. We present the percentage of batches not complying with the potential criteria, in relation to the risk reduction attending totally efficient treatment of these batches. We find different risk estimates and different impacts of MCs in different countries, which offers a practical and flexible tool for risk managers to select the most appropriate MC by weighing the costs (i.e. non-compliant batches) and the benefits (i.e. reduction in public health risk). Our analyses show that the estimated percentage of batches not complying with the MC is better correlated with the risk estimate than surrogate risk measures like the flock prevalence or the arithmetic mean concentration of bacteria on carcasses, and would therefore be a good measure for the risk of Campylobacter on broiler meat in a particular country. Two uncertain parameters in the model are the ratio of within- and between-flock variances in concentrations, and the transition factor of skin sample concentrations to concentrations on the meat. Sensitivity analyses show that these parameters have a considerable effect on our results, but the impact of their uncertainty is small compared to that of the parameters defining the Microbiological Criterion and the concentration on the meat.     

Occurrence of fastidious Campylobacter spp. in fresh meat and poultry using an adapted cultural protocol

This study used an adapted cultural protocol for the recovery of fastidious species of Campylobacter, to gain a more accurate understanding of the diversity of Campylobacter populations in fresh meats. Chicken (n=185), pork (n=179) and beef (n=186) were collected from supermarkets and butchers throughout the Republic of Ireland. Samples were enriched in Campylobacter enrichment broth for 24h under an atmosphere of 2.5% O(2), 7% H(2), 10% CO(2), and 80.5% N(2). The enriched samples were then filtered onto non-selective Anaerobe Basal Agar supplemented with lysed horse blood using mixed ester filter membranes. Isolates were identified by both genus and species-specific PCR assays and biochemical testing. The incidence of campylobacters on beef (36%) was significantly higher than on pork (22%) or chicken (16%), and far exceeds previously reported prevalence levels. The method was successful in recovering 7 species of Campylobacter, including the fastidious spp. C. concisus and C. mucosalis, from chicken meat, and 10 species, including C. concisus, C. curvus, C. mucosalis, C. sputorum, and C. upsaliensis, from minced beef. The isolation of C. concisus and C. upsaliensis from meat in this study is of particular significance, due to their emerging clinical relevance. The results of this study confirm that the diversity of Campylobacter species on fresh meats is greater than previously reported and highlights the bias of cultural methods towards the recovery of C. jejuni.     

A comparison of three modelling approaches for quantitative risk assessment using the case study of Salmonella spp. in poultry meat

A comprehensive review of both the scientific literature and industry practices was undertaken to identify and quantify all sources of contamination throughout the entire poultry meat production chain by Salmonella spp. This information was used to develop a quantitative risk assessment (QRA) model for Salmonella in the production chain from the breeder farm to the chilled carcass. This was subsequently used as the basis on which to compare the merits of three approaches to QRA modelling in such systems. The original model used a Bayesian Network (BN). The second method was a Markov chain Monte Carlo (MCMC) approach, a numerical Bayesian technique which retained a similar network structure but allowed further development, such as the separation of variability and uncertainty. The third method was a more detailed simulation model. The BN responds immediately to changes, such as entering evidence, because it does not use simulation and can propagate information from any point in the network to all others by Bayesian inference. However, it requires all the variables to be discrete, which introduces errors if continuous variables have to be discretized. These errors can accumulate. The MCMC approach does not require discrete variables while retaining some of the properties of the BN model, such as the ability to draw inferences from evidence. Finally, the simulation offers greater flexibility, such as consideration of the individual carcass, but may be more complex to implement as a result and sacrifices the ability to propagate evidence.     

屠宰过程黄羽肉鸡弯曲菌的定量风险评估

目的 检测屠宰过程黄羽肉鸡弯曲菌阳性率和污染水平,建立屠宰过程黄羽肉鸡弯曲菌的定量风险评估模型,探明其污染的关键风险点。方法 用传统分离鉴定方法和最近似数法（most probable numbers,MPN）定量法对屠宰不同环节弯曲菌阳性率和污染水平进行检测,接着运用描述函数对数据进行拟合,并采用@Risk软件进行重复性检验和敏感性分析。结果 弯曲菌阳性率和污染水平以活鸡肛拭环节最高（53.60％,1.8300 logMPN/m2）,其次为打毛和开膛环节（27.50％,0.5000 logMPN/m2和18.10％,0.0270 logMPN/m2）。根据函数拟合结果建立弯曲菌污染定量风险评估模型,蒙特卡洛（Monte Carlo）模拟分析显示肛拭环节弯曲菌阳性率和污染水平最高(52.92%,1.8896 logMPN),其次是打毛和开膛环节(27.46%,0.4680 logMPN和14.74%,0.4910 logMPN),各个模拟环节数值与分离鉴定结果误差较小（P<0.05）,表明模型具有良好的准确性;敏感性分析获得黄羽肉鸡屠宰过程弯曲菌污染的关键风险点为打毛和开膛环节,相关系数分别为0.77和-0.39,高于其他环节。结论 本研究以屠宰过程黄羽肉鸡弯曲菌为研究对象进行风险评估,成功建立弯曲菌暴露评估模型,且模型具有较好的准确性,同时揭示了屠宰过程弯曲菌防控的关键风险点,为黄羽肉鸡弯曲菌的防控和风险评估奠定基础。     

Occurrence of Campylobacter spp. in poultry and poultry products for sale on the Polish retail market

In 2007 and 2008, a monitoring study was carried out in Poland to examine the occurrence of thermotolerant Campylobacter spp. in raw and cooked chicken products available on the retail market. A total of 912 samples were tested: 443 samples of raw chicken meat, 146 samples of giblets, and 323 ready-to-eat poultry products (150 samples of spit-roasted chicken, 56 samples of smoked chicken, and 117 samples of paté and cold meats). A high level of contamination of raw chicken meat (51.7% of samples) and chicken giblets (47.3% of samples) was detected. However, thermotolerant Campylobacter spp. were found in only 1.2% of the ready-to-eat poultry products.     

Predominant strains of thermophilic Campylobacter spp. in a German poultry slaughterhouse

Campylobacter causes bacterial diarrhoea in man and is a common foodborne pathogen, that has been associated mainly with poultry carcasses and processed poultry products as well as with drinking water. Genotyping of Campylobacter spp. from poultry was done in order to prove if predominant stable strains in the food chain are present. The influence of the slaughter process on the stability should be determined. Thermophilic Campylobacter spp. from eight poultry flocks were isolated from cloacal swabs, carcasses and offal at different abattoir processing steps to determine their stability. DNA-fingerprinting was done using Pulsed-Field Gel Electrophoresis (PFGE) with two enzymes (SmaI and KpnI) and ribotyping. More than 150 Campylobacter strains were ribotyped and these data were combined with the results of PFGE. Molecular typing showed that strains found in cloacal swabs before processing could also be isolated from carcasses and offal at different processing steps representing predominating stable strains. Strains with varying molecular pattern could additionally be detected at different processing steps. Both genotyping methods identified in agreement flock-specific strains. These remained stable through the slaughter of poultry and were not altered through the slaughter process. Despite the known genetic variability of thermophilic Campylobacter, stable predominant strains could be identified in the poultry slaughter process and those strains can thus enter the food chain.     

Dye use in fresh meat preparations and meat products: a survey by a validated method based on HPLC-UV-diode array detection as a contribution to risk assessment

The use of dyes in meats has to be monitored, due to food safety concerns. The presence of twelve dyes (Amaranth, Ponceau 4R, Carmine, Ponceau SX, Ponceau 3R, Allura Red AC, Carmoisine, Erythrosine, Sudan I, Sudan II, Sudan III and Sudan IV) in meat was investigated in 130 meat product and fresh meat preparation samples, and the dietary exposure was estimated. Carmine and Ponceau 4R were the identified dyes. Except for one sample of salami, they were regularly indicated on the label, and their concentrations were in the range 1.3–8.1 and 6.2–86.4 mg kg⁻¹ for Ponceau 4R and Carmine, respectively. Concerning fresh meat preparations, Carmine was detected in three samples, confirming that this dye is still used, although it is no longer authorised in these products. Regarding dietary exposure estimate, the daily intake from meat product consumption resulted lower than 1% of the ADI, both for Carmine and Ponceau 4R.     

Resistance patterns of Campylobacter spp. strains isolated from poultry carcasses in a big Swiss poultry slaughterhouse

The aim of this study was to determine resistance patterns of strains of Campylobacter spp. isolated from poultry carcasses in one of the two big Swiss poultry slaughterhouses. A variety of antibiotics with clinical relevance in human and/or in veterinary medicine was tested. In addition, the results of the disc diffusion method, E-test and microdilution broth methods were compared. Of the 195 Campylobacter jejuni strains isolated from 195 poultry carcasses from 21 flocks, 134 strains were susceptible in vitro to all tested antibiotics. Sixty-one strains (31.3%, from eight flocks) showed resistance. Forty-one strains were resistant to a single antibiotic-34 to streptomycin, 6 to ampicillin and 1 to ciprofloxacin. Eighteen strains (from two flocks) showed combined resistance to erythromycin and streptomycin, two strains to ciprofloxacin and streptomycin. None of the isolates was resistant to tetracycline. The data of this first study in Switzerland show a favourable resistance situation for C. jejuni strains against erythromycin, tetracycline and ciprofloxacin. The disc diffusion method was found to be a reliable and easy tool for monitoring the prevalence of resistant C. jejuni strains. For surveillance of changes in the susceptibility concentration levels to antimicrobial agents, however, a MIC method should be used. Further investigations along the whole poultry production chain (farm, slaughterhouse and retail levels) are now necessary in order to confirm the resistance situation.     

零售生鸡肉中沙门菌污染对居民健康影响的暴露评估

目的评估零售生鸡肉中沙门菌污染的健康风险及其潜在的干预措施。方法利用零售生鸡肉中沙门菌定量监测数据以及零售和家庭生鸡肉储存加工专项调查结果,采用Monte Carlo概率评估方法,估计我国居民通过厨房内交叉污染发生鸡源性沙门菌食物中毒的风险,并评价潜在的干预措施效果。结果本研究构建了从零售到餐桌的生鸡肉-沙门菌交叉污染模型,模型估计生鸡肉经过零售储存、抵达居民家里和经过家庭储存后其沙门菌浓度(lg MPN/g)从零售前的-0.017,分别增长到2.163、2.241和3.028,估计我国居民每餐发生鸡源性沙门菌食物中毒的风险为0.171(95%置信区间:0.000~0.767),其中零售阶段生鸡肉的储存方式是影响发病风险的最重要因素(回归系数=0.72),情景分析提示,如果零售阶段采用冷冻或者冷藏储存,我国居民每餐发病风险可以降为0.031(95%置信区间:0.000~0.522)。结论我国居民鸡源性沙门菌食物中毒的风险较高,应当加强零售环节生鸡肉的冷链管理。     

The European Union control strategy for Campylobacter spp. in the broiler meat chain

Campylobacter is the most common cause of bacterial gastroenteritis worldwide and the most frequently reported foodborne pathogen in the European Union (EU). While campylobacteriosis is generally self-limiting, some patients could develop severe sequelae. The predominant source of infection is poultry. This review addresses the most relevant factors influencing the prevalence and contamination level of Campylobacter spp. in the poultry chain continuum. The emphasis was put on the novel control strategy for Campylobacter that is based on evidence-based risk assessment and the introduction of process hygiene criterion intended for monitoring the prevalence and counts of Campylobacter spp. on broiler carcasses at slaughter level. The reduction of Campylobacter spp. in the poultry meat chain in the EU can only be achieved with an integrated meat safety assurance approach. This includes primary interventions at the level of the poultry farm, implementation of effective control measures at slaughterhouses, and fostering awareness campaigns aimed at consumers.     

Quantitative risk assessment of thermophilic Campylobacter spp. and cross-contamination during handling of raw broiler chickens evaluating strategies at the producer level to reduce human campylobacteriosis in Sweden

Campylobacter is a major bacterial cause of infectious diarrheal illness in Sweden and in many other countries. Handling and consumption of chicken has been identified as important risk factors. The purpose of the present study was to use data from a national baseline study of thermophilic Campylobacter spp. in raw Swedish broiler chickens in order to evaluate some risk management strategies and the frequency of consumer mishandling, i.e., handling leading to possible cross-contamination. A probabilistic model describing variability but not uncertainty was developed in Excel and @Risk. The output of the model was the probability of illness per handling if the chicken was mishandled. Uncertainty was evaluated by performing repeated simulations and substituting model parameters, distributions and software (Analytica). The effect of uncertainty was within a factor of 3.2 compared to the baseline scenario. For Campylobacter spp. prevalence but not concentration, there was a one-to-one relation with risk. The effect of a 100-fold reduction in the levels of Campylobacter spp. on raw chicken reduced the risk by a factor of 12 (fresh chicken) to 30 (frozen chicken). Highly-contaminated carcasses contributed most to risk and it was estimated that by limiting the contamination to less than 4 log CFU per carcass, the risk would be reduced to less than 17% of the baseline scenario. Diverting all positive flocks to freezing was estimated to result in 43% as many cases as the baseline. The second best diversion option (54% of baseline cases) was to direct all chickens from the two worst groups of producers, in terms of percentages of positive flocks delivered, to freezing. The improvement of using diverting was estimated to correspond to between 5 to 767 fewer reported cases for the different strategies depending on the assumptions of the proportion of reported cases (1 to 50%) caused by Campylobacter spp. from Swedish chicken. The estimated proportion of consumer mishandlings sufficient to explain 1 to 50% of the reported campylobacteriosis cases was 0.005-0.25%, or taking estimated underreporting into consideration, was 0.05-2.6%. The strategy of using a diversion treatment, e.g., freezing, based on the past performance of producers was promising, but needs to be evaluated further. Although challenging, consumer education has a great potential given the direct relation between behaviour and risk. However, any improvements following implementation of these strategies may be hard to detect if less than 50% of reported cases are exposed via chicken and the cross-contamination route.     

Prevalence of thermophilic Campylobacter spp. in ready-to-eat foods and raw poultry in Northern Ireland

Although there have been numerous studies investigating the prevalence of campylobacters in animals and raw meats, there are limited data on the persistence of these organisms in ready-to-eat (RTE) foodstuffs. Although poultry is now well established as a major reservoir of thermophilic campylobacters, it is widely assumed that hazard analysis critical control point (HACCP) controls in commercial and industrial settings are effective in eliminating this hazard through thorough cooking of RTE products. Therefore, it was the primary aim of this study to investigate the effectiveness of HACCP controls in eliminating campylobacters in such cooked RTE foods by attempting to isolate viable organisms from product. Concurrently, the results of this study demonstrate that local poultry is highly contaminated with campylobacters. Commercially available RTE foodstuffs (n = 2,030) consisting of 1,061 poultry-related cooked products and 969 other products were analyzed and were not found to contain thermophilic Campylobacter spp. In addition, 107 raw chickens (63 fresh birds and 44 frozen birds) were sampled, and 94% of the fresh birds and 77% of the frozen birds examined were demonstrated to be contaminated with campylobacters, with Campylobacter jejuni, Campylobacter coli, and Campylobacter lari accounting for 69, 30, and 1% of the contaminating organisms, respectively. In general, commercially available RTE foodstuffs, including cooked poultry, are not commonly contaminated with campylobacters and thus do not appear to represent a significant cause of clinical infection of Campylobacter spp. in Northern Ireland. However, raw poultry produce, including fresh and frozen chicken, frequently tested positive for campylobacters. Implementation of HACCP systems by food processors will help to minimize and/or eliminate the risk posed by this organism to the consumer.     

Distribution of Campylobacter spp. in selected U.S. poultry production and processing operations.

A study was conducted of 32 broiler flocks on eight different farms, belonging to four major U.S. producers. The farms were studied over I complete calendar year. Overall, 28 (87.5%) of the flocks became Campylobacter positive, and only four (12.5%) remained negative throughout the 6- to 8-week rearing period. In the majority of flocks, sampled every 2 weeks throughout production, Campylobacter-positive fecal and cecal samples were not detected until 4 to 8 weeks of age. In only six of the flocks were environmental samples found to be positive before shedding of Campylobacter was detected in the birds. Even in some of the Campylobacter-negative flocks, contamination of the rearing environment was positive for Campylobacter but did not result in the birds subsequently excreting the organism. These findings are discussed in relation to U.S. husbandry practices and present uncertainty about sources of Campylobacter infection for poultry flocks. Birds were often transported to the processing plant in coops that were already contaminated with Campylobacter, and the organisms were sometimes found in samples of scald water and chill water. After chilling, the proportions of Campylobacter-positive carcasses from different producers ranged from 21.0 to 40.9%, which is lower than in other studies, and possible reasons are considered.     

鸡肉中弯曲菌定量检测方法的建立与初步应用

目的参照国标方法,建立鸡肉中弯曲菌定量检测的CCDA平板计数法。方法通过对选择性CCDA培养基中添加不同浓度组合的抗生素和生长促进剂,确定最佳添加浓度组合,并与普通CCDA平板计数法进行比较,建立鸡肉中弯曲菌定量检测方法,同时评价该方法的特异性和检测限。结果添加一定浓度抗生素和生长促进剂的选择性CCDA培养基和普通CCDA培养基对弯曲菌标准菌株定量计数的吻合度为(100±5)%;除弯曲菌外,其他5种肠道细菌在该CCDA培养基中均不能生长;该方法对弯曲菌菌悬液可检测至10 CFU/mL。运用该方法对50份鸡肉样品进行调查研究,共检测出22份阳性样品,弯曲菌检出率为44%,平均检测值为20CFU/100 cm~2,检测结果与国标方法阳性符合率为100%。结论该方法简便、特异性好、准确度高,为定量检测鸡肉中弯曲菌提供了新技术。     

Comparison of three methods for detecting Campylobacter spp. in chilled or frozen meat

There is a demand from the meat industry as well as from public health authorities for a simple and rapid detection method for thermophilic Campylobacter spp. from food. Hence, we compared different isolation procedures for their usefulness for this purpose. Bolton enrichment medium without blood, incubated statically in stomacher bags in microaerophilic atmosphere, detected more samples positive for thermophilic Campylobacter spp. than did Preston enrichment broth in bottles with small headspace and tight caps, incubated in aerobic atmosphere. Use of an automated antigen detection system to identify enrichment cultures positive for Campylobacter spp. was as sensitive as selective agars, and reduced the detection time by 24 h. Campylobacter spp. were recovered from 18.4% of the 461 samples tested. The prevalence was highest in refrigerated poultry meat (52% of the 80 samples tested) and poultry offal (41% of the 44 samples tested).     

Quantitative risk assessment of human campylobacteriosis associated with thermophilic Campylobacter species in chickens

A quantitative risk assessment comprising the elements hazard identification, hazard characterization, exposure assessment, and risk characterization has been prepared to assess the effect of different mitigation strategies on the number of human cases in Denmark associated with thermophilic Campylobacter spp. in chickens. To estimate the human exposure to Campylobacter from a chicken meal and the number of human cases associated with this exposure, a mathematical risk model was developed. The model details the spread and transfer of Campylobacter in chickens from slaughter to consumption and the relationship between ingested dose and the probability of developing campylobacteriosis. Human exposure was estimated in two successive mathematical modules. Module 1 addresses changes in prevalence and numbers of Campylobacter on chicken carcasses throughout the processing steps of a slaughterhouse. Module 2 covers the transfer of Campylobacter during food handling in private kitchens. The age and sex of consumers were included in this module to introduce variable hygiene levels during food preparation and variable sizes and compositions of meals. Finally, the outcome of the exposure assessment modules was integrated with a Beta-Poisson dose-response model to provide a risk estimate. Simulations designed to predict the effect of different mitigation strategies showed that the incidence of campylobacteriosis associated with consumption of chicken meals could be reduced 30 times by introducing a 2 log reduction of the number of Campylobacter on the chicken carcasses. To obtain a similar reduction of the incidence, the flock prevalence should be reduced approximately 30 times or the kitchen hygiene improved approximately 30 times. Cross-contamination from positive to negative flocks during slaughter had almost no effect on the human Campylobacter incidence, which indicates that implementation of logistic slaughter will only have a minor influence on the risk. Finally, the simulations showed that people in the age of 18-29 years had the highest risk of developing campylobacteriosis.     

The risk of transfer of foodborne bacterial hazards in Turkey through the consumption of meat; risk ranking of muscle foods with the potential to transfer Campylobacter spp.

This paper presents a simple approach to semi-quantitatively estimating the risk for human foodborne campylobacteriosis in Turkey, with a focus on typical/traditional meat and meat dishes. The following factors are considered: prevalence/concentration of the pathogen in raw meat according to species, changes in the pathogen’s titre as a result of heat treatment and cross-contamination, serving frequency and size, and demographic data. Regional differences as well as differences between social groups are considered in particular. The biological hazard “Campylobacter” is characterized as associated with conditions prevailing in the meat chain and this information is linked to food consumption and other data thus allowing an estimate of consumers’ exposure to Campylobacter via typical Turkish meat dishes. The latter are ranked on the basis of the presence of meat components and the associated risks.     

Quantitative risk assessment of human campylobacteriosis related to the consumption of chicken meat in two Italian regions

Campylobacteriosis is the most frequently reported zoonotic disease in humans within the European Union. The consumption of contaminated chicken meat is considered one of the main sources of human infection. Although there are no official data on the incidence of Campylobacter infection in Italy, the available studies suggest that this infection is a major problem also in Italy. The authors developed a simulation model to quantitatively estimate the expected annual number of human cases of campylobacteriosis in the Italian regions of Abruzzo and Molise, due to the cross-contamination during the handling of Campylobacter jejuni contaminated chicken meat in domestic kitchen. The authors considered two different models for the dose-response relationship, given their crucial effects on the model's outputs. The expected percentage of human population, experiencing Campylobacter gastroenteritis episodes every year in Abruzzo e Molise regions, varied between 0.8% and 1.8%, according to the dose-response model.     

High occurrence rates of enrofloxacin and ciprofloxacin residues in retail poultry meat revealed by an ultra-sensitive mass-spectrometric method,and antimicrobial resistance to fluoroquinolones in Campylobacter spp

An ultra-sensitive mass spectrometric confirmation and quantification method for the determination of selected fluoroquinolones—enrofloxacin and its main metabolite ciprofloxacin—was developed and validated in poultry meat samples. The achieved limits of quantification were 1 ng kg^?1 for enrofloxacin and 10 ng kg^?1 for ciprofloxacin. The analysis of 40 retail poultry samples originating from Estonia, Latvia, Lithuania, Poland and France revealed that 93% of samples contained residues of enrofloxacin in the range from 3.3 to 1126 ng kg^?1. Previous studies have shown high levels of antimicrobial resistance to fluoroquinolones, particularly in Campylobacter spp. and various faecal indicators isolated from broiler meat. Consequently, the revealed widespread usage of fluoroquinolones in the poultry industry may result in the further emergence of antimicrobial resistance of Campylobacter in the food chain.