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Campylobacter is a common cause of food poisoning in many countries, with broilers being the main source. Organic and free-range broilers are more frequently Campylobacter-positive than conventionally raised broilers and may constitute a higher risk for human infections. Organic and free-range broilers may get exposed to Campylobacter from environmental reservoirs and livestock farms, but the relative importance of these sources is unknown. The aim of the study was to describe similarities and differences between the genetic diversity of the Campylobacter isolates collected from free-range/organic broilers with those isolated from conventional broilers and other animal hosts (cattle, pigs, and dogs) in Denmark to make inferences about the reservoir sources of Campylobacter to free-range broilers. The applied aggregated surveillance data consisted of sequenced Campylobacter isolates sampled in 2015 to 2017 and 2018 to 2021. The data included 1,102 isolates from free-range (n = 209), conventional broilers (n = 577), cattle (n = 261), pigs (n = 30), and dogs (n = 25). The isolates were cultivated from either fecal material (n = 434), food matrices (n = 569), or of nondisclosed origin (n = 99). Campylobacter jejuni (94.5%) dominated and subtyping analysis found 170 different sequence types (STs) grouped into 75 clonal complexes (CCs). The results suggest that CC-21 and CC-45 are the most frequent CCs found in broilers. The relationship between the CCs in the investigated sources showed that the different CCs were shared by most of the animals, but not pigs. The ST-profiles of free-range broilers were most similar to that of conventional broilers, dogs and cattle, in that order. The similarity was stronger between conventional broilers and cattle than between conventional and free-range broilers. The results suggest that cattle may be a plausible reservoir of C. jejuni for conventional and free-range broilers, and that conventional broilers are a possible source for free-range broilers or reflect a dominance of isolates adapted to the same host environment. Aggregated data provided valuable insight into the epidemiology of Campylobacter sources for free-range broilers, but time-limited sampling of isolates from different sources within a targeted area would hold a higher predictive value., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The need to control transboundary animal disease outbreaks is widely recognised, as is the need for evidence-based decisions regarding which control measures to implement. Key data and information are required to inform this evidence base. To ensure effective communication of the evidence, a rapid process of collation, interpretation and translation is required. This paper describes how epidemiology can provide the framework through which relevant specialists can be engaged to this end, and highlights the central role of epidemiologists, with their unique combination of skills, in this process. It provides an example of an evidence team led by epidemiologists, namely the United Kingdom National Emergency Epidemiology Group, which was established to address this need. It then goes on to consider the different strands of epidemiology, the need for a wide multidisciplinary approach, and the importance of training and preparedness activities to facilitate rapid response.

To forge a path towards livestock disease emergency preparedness in Denmark, 15 different strategies to mitigate foot-and-mouth disease (FMD) were examined by modelling epidemics initiated in cattle, pig or small ruminant herds across various production systems located in four different Danish regions (Scenario 1), or in one specific livestock production system within each of the three species geographically distributed throughout Denmark (Scenario 2). When additional mitigation strategies were implemented on top of basic control strategies in the European foot-and-mouth disease spread model (EuFMDiS), no significant benefits were predicted in terms of the number of infected farms, the epidemic control duration, and the total economic cost. Further, the model results indicated that the choice of index herd, the resources for outbreak control, and the detection time of FMD significantly influenced the course of an epidemic. The present study results emphasise the importance of basic mitigation strategies, including an effective back-and-forward traceability system, adequate resources for outbreak response, and a high level of awareness among farmers and veterinarians concerning the detection and reporting of FMD at an early stage of an outbreak for FMD control in Denmark., Competing Interests: The authors declare no conflict of interest.

There has been a renewed focus on threats to the human-animal-environment interface as a result of the COVID-19 pandemic, and investments in One Health collaborations are expected to increase. Efforts to monitor the development of One Health Networks (OHNs) are essential to avoid duplication or misalignment of investments. This Series paper shows the global distribution of existing OHNs and assesses their collective characteristics to identify potential deficits in the ways OHNs have formed and to help increase the effectiveness of investments. We searched PubMed, Google, Google Scholar, and relevant conference websites for potential OHNs and identified 184 worldwide for further analysis. We developed four case studies to show important findings from our research and exemplify best practices in One Health operationalisation. Our findings show that, although more OHNs were formed in the past 10 years than in the preceding decade, investment in OHNs has not been equitably distributed; more OHNs are formed and headquartered in Europe than in any other region, and emerging infections and novel pathogens were the priority focus area for most OHNs, with fewer OHNs focusing on other important hazards and pressing threats to health security. We found substantial deficits in the OHNs collaboration model regarding the diversity of stakeholder and sector representation, which we argue impedes effective and equitable OHN formation and contributes to other imbalances in OHN distribution and priorities. These findings are supported by previous evidence that shows the skewed investment in One Health thus far. The increased attention to One Health after the COVID-19 pandemic is an opportunity to focus efforts and resources to areas that need them most. Analyses, such as this Series paper, should be used to establish databases and repositories of OHNs worldwide. Increased attention should then be given to understanding existing resource allocation and distribution patterns, establish more egalitarian networks that encompass the breadth of One Health issues, and serve communities most affected by emerging, re-emerging, or endemic threats at the human-animal-environment interface., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Campylobacter spp. are some of the most important food-borne zoonoses in Europe and broiler meat is considered the main source of Campylobacter infections. Organic and free-range broilers have access to outdoor reservoirs of Campylobacter and are more frequently infected at slaughter than the conventional broiler flocks. Limitations to biosecurity and treatment options in these production types calls for additional solutions. This review examines intervention methods with sufficient strength and quality, which are able to reduce the load of Campylobacter safely and efficiently and discuss their applicability in organic and free-range broiler production. Four different products passed the inclusion criteria and their quality examined: ferric tyrosine chelate, a prebiotic fermentation product of Saccharomyces cerevisiae, short-chain fatty acid butyrate coated on microbeads added to feed, and a mix of organic acids added to the drinking water. Though potential candidates for reducing Campylobacter in broilers were identified, there is a lack of large scale intervention studies that demonstrate an effect under field conditions of a free-range broiler production., (© 2022. The Author(s).)

What Is Already Known on This Topic?: Vibrio parahaemolyticus ( V. parahaemolyticus ) is frequently resistant to common antimicrobials such as ampicillin and generally highly susceptible to most clinically used antimicrobials., What Is Added by This Report?: V. parahaemolyticus were highly resistant to cefazolin and ampicillin: 94.4% and 37.0%, respectively. However, it was below 3% resistance to all 10 other antimicrobials including clinically relevant agents and even imipenem. The overall levels of antimicrobial resistance and multidrug resistance were 95.1% and 3.3%, respectively. The distribution of antimicrobial resistance and the multidrug resistance had regional, temporal, sexual, and isolated source strain variation., What Are the Implications for Public Health Practice?: This study provides data on drug resistance of V. parahaemolyticus in Chinese clinical settings, which will help develop a public health strategy., Competing Interests: Conflicts of interest: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2021.)

Regular evaluation of integrated surveillance for antimicrobial use (AMU) and resistance (AMR) in animals, humans, and the environment is needed to ensure system effectiveness, but the question is how. In this study, six different evaluation tools were assessed after being applied to AMU and AMR surveillance in eight countries: (1) ATLASS: the Assessment Tool for Laboratories and AMR Surveillance Systems developed by the Food and Agriculture Organization (FAO) of the United Nations, (2) ECoSur: Evaluation of Collaboration for Surveillance tool, (3) ISSEP: Integrated Surveillance System Evaluation Project, (4) NEOH: developed by the EU COST Action "Network for Evaluation of One Health," (5) PMP-AMR: The Progressive Management Pathway tool on AMR developed by the FAO, and (6) SURVTOOLS: developed in the FP7-EU project "RISKSUR." Each tool was scored using (i) 11 pre-defined functional aspects (e.g., workability concerning the need for data, time, and people); (ii) a strengths, weaknesses, opportunities, and threats (SWOT)-like approach of user experiences (e.g., things that I liked or that the tool covered well); and (iii) eight predefined content themes related to scope (e.g., development purpose and collaboration). PMP-AMR, ATLASS, ECoSur, and NEOH are evaluation tools that provide a scoring system to obtain semi-quantitative results, whereas ISSEP and SURVTOOLS will result in a plan for how to conduct evaluation(s). ISSEP, ECoSur, NEOH, and SURVTOOLS allow for in-depth analyses and therefore require more complex data, information, and specific training of evaluator(s). PMP-AMR, ATLASS, and ISSEP were developed specifically for AMR-related activities-only ISSEP included production of a direct measure for "integration" and "impact on decision making." NEOH and ISSEP were perceived as the best tools for evaluation of One Health (OH) aspects, and ECoSur as best for evaluation of the quality of collaboration. PMP-AMR and ATLASS seemed to be the most user-friendly tools, particularly designed for risk managers. ATLASS was the only tool focusing specifically on laboratory activities. Our experience is that adequate resources are needed to perform evaluation(s). In most cases, evaluation would require involvement of several assessors and/or stakeholders, taking from weeks to months to complete. This study can help direct future evaluators of integrated AMU and AMR surveillance toward the most adequate tool for their specific evaluation purpose., Competing Interests: MB was involved in the development of ECoSur and LN was involved in the development of NEOH. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sandberg, Hesp, Aenishaenslin, Bordier, Bennani, Bergwerff, Chantziaras, De Meneghi, Ellis-Iversen, Filippizi, Mintiens, Nielsen, Norström, Tomassone, van Schaik and Alban.)

Collaboration across sectors, disciplines and countries is a key concept to achieve the overarching One Health (OH) objective for better human, animal and environmental health. Differences in terminology and interpretation of terms are still a significant hurdle for cross-sectoral information exchange and collaboration within the area of OH including One Health Surveillance (OHS). The development of the here described glossary is a collaborative effort of three projects funded within the One Health European Joint Programme (OHEJP). We describe the infrastructure of the OHEJP Glossary, as well as the methodology to create such a cross-sectoral web resource in a collaborative manner. The new OHEJP Glossary allows OH actors to identify terms with different or shared interpretation across sectors. Being aware of such differences in terminology will help overcome communication hurdles in the future and consequently support collaboration and a more inclusive development of OHS. The OHEJP Glossary was implemented as a web-based, user-friendly and searchable infrastructure that complies with the Findable, Accessible, Interoperable, Reusable (FAIR) data principles. Maintenance, enrichment and quality control of the OHEJP Glossary is supported through a flexible and updatable curation infrastructure. This increases the uptake potential and exploitation of the OHEJP Glossary by other OH initiatives or tools and services., Competing Interests: None., (© 2021 The Authors.)

Cross-sector communication, collaboration and knowledge exchange are still significant challenges for practical adoption of the One Health paradigm. To address these needs the "One Health Surveillance Codex" (OHS Codex) was established to provide a framework for the One Health community to continuously share practical solutions (e.g. tools, technical resources, guidance documents and experiences) applicable for national and international stakeholders from different One Health Surveillance sectors. Currently, the OHS Codex provides a number of resources that support the adoption of the OH paradigm in areas linked to the harmonization and interpretation of surveillance data. The OHS Codex framework comprises four high-level "action" principles, which respectively support collaboration, knowledge exchange, data interoperability, and dissemination. These principles match well with priority areas identified in the "Tripartite Guide to Addressing Zoonotic Diseases in Countries" published by WHO, FAO and OIE. Within each of the four principles, the OHS Codex provides a collection of useful resources as well as pointers to success stories for the application of these resources. As the OHS Codex is designed as an open community framework, it will continuously evolve and adapt to the needs of the OH community in the future., Competing Interests: None., (© 2021 The Authors.)

Background: Integrated antimicrobial resistance (AMR) surveillance programmes require regular evaluation to ensure they are fit for purpose and that all actors understand their responsibilities. This will strengthen their relevance for the clinical setting, which depends heavily on continued access to effective treatment options. Several evaluation tools addressing different surveillance aspects are available., Objectives: The aim was to understand the strengths and weaknesses of three evaluation tools, and to improve guidance on how to choose a fit-for-purpose tool., Sources: Three tools were assessed: (a) AMR-PMP-the Progressive Management Pathway tool on AMR developed by the Food and Agriculture Organization (FAO) of the United Nations, (b) NEOH developed by the EU COST Action 'Network for Evaluation of One Health' and (c) SURVTOOLS developed in an FP7-EU project 'RISKSUR'. Each tool was assessed with regard to contents, required evaluation processes including stakeholder engagement and resource demands, integration coverage across relevant sectors and applicability. They were compared using a predefined scoring scheme and a strengths-weaknesses-opportunities-threats (SWOT)-like format for commenting., Content: All three tools address multiple decision-making levels and aspects of stakeholder engagement. NEOH focuses on system features, learning, sharing, leadership and infrastructure, and requires a description of the underlying system in which AMR develops. AMR-PMP focuses on four areas: awareness, evidence, governance and practices and assesses the implementation degree of pre-chosen aspects within these areas. This requires less of the evaluator, but warrants participation of multiple stakeholders. SURVTOOL provides information and references on how to evaluate effectiveness, process and comprehensiveness of surveillance programmes. All three tools require veterinary epidemiology expertise and varying levels of evaluation methodology training to use appropriately., Implications: The tools covered AMR surveillance and One Health aspects to varying degrees. This study provides guidance on aspects to consider when choosing between available tools and embarking on an evaluation of integrated surveillance., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Burden of disease metrics are increasingly established to prioritize food safety interventions. We estimated the burden of disease caused by seven foodborne pathogens in Denmark in 2017: Campylobacter , Salmonella , Shiga toxin-producing Escherichia coli , norovirus, Yersinia enterocolitica , Listeria monocytogenes , and Toxoplasma gondii . We used public health surveillance data and scientific literature to estimate incidence, mortality, and total disability-adjusted life year (DALY) of each, and linked results with estimates of the proportion of disease burden that is attributable to foods. Our estimates showed that Campylobacter caused the highest burden of disease, leading to a total burden of 1709 DALYs (95% uncertainty interval [UI] 1665-1755), more than threefold higher than the second highest ranked pathogen ( Salmonella: 492 DALYs; 95% UI 481-504). Campylobacter still led the ranking when excluding DALYs attributable to nonfoodborne routes of exposure. The total estimated incidence was highest for norovirus, but this agent ranked sixth when focusing on foodborne burden. Salmonella ranked second in terms of foodborne burden of disease, followed by Listeria and Yersinia . Foodborne congenital toxoplasmosis was estimated to cause the loss of ∼100 years of healthy life, a burden that was borne by a low number of cases in the population. The ranking of foodborne pathogens varied substantially when based on reported cases, estimated incidence, and burden of disease estimates. Our results reinforce the need to continue food safety efforts throughout the food chain in Denmark, with a particular focus on reducing the incidence of Campylobacter infections.

The 2011 EFSA opinion on Campylobacter was updated using more recent scientific data. The relative risk reduction in EU human campylobacteriosis attributable to broiler meat was estimated for on-farm control options using Population Attributable Fractions (PAF) for interventions that reduce Campylobacter flock prevalence, updating the modelling approach for interventions that reduce caecal concentrations and reviewing scientific literature. According to the PAF analyses calculated for six control options, the mean relative risk reductions that could be achieved by adoption of each of these six control options individually are estimated to be substantial but the width of the confidence intervals of all control options indicates a high degree of uncertainty in the specific risk reduction potentials. The updated model resulted in lower estimates of impact than the model used in the previous opinion. A 3-log 10 reduction in broiler caecal concentrations was estimated to reduce the relative EU risk of human campylobacteriosis attributable to broiler meat by 58% compared to an estimate larger than 90% in the previous opinion. Expert Knowledge Elicitation was used to rank control options, for weighting and integrating different evidence streams and assess uncertainties. Medians of the relative risk reductions of selected control options had largely overlapping probability intervals, so the rank order was uncertain: vaccination 27% (90% probability interval (PI) 4-74%); feed and water additives 24% (90% PI 4-60%); discontinued thinning 18% (90% PI 5-65%); employing few and well-trained staff 16% (90% PI 5-45%); avoiding drinkers that allow standing water 15% (90% PI 4-53%); addition of disinfectants to drinking water 14% (90% PI 3-36%); hygienic anterooms 12% (90% PI 3-50%); designated tools per broiler house 7% (90% PI 1-18%). It is not possible to quantify the effects of combined control activities because the evidence-derived estimates are inter-dependent and there is a high level of uncertainty associated with each., (© 2020 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)

The pandemic of new coronavirus disease COVID-19 is threatening our health, economy and life style. Collaborations across countries and sectors as a One Health World could be a milestone. We propose a general protocol, for setting timely active random surveillance of COVID-19, at the human community level, with systematic repeated detection efforts. Strengths and limitations are discussed. If considered applicable by public health, the protocol could evaluate the status of COVID-19 epidemics consistently and objectively., Competing Interests: None of the authors have any conflict of interests, (© 2020 The Authors.)

Antibiotic consumption in pigs can be optimized by developing treatment guidelines, which encourage veterinarians to use effective drugs with low probability of developing resistance of importance for human health. In Denmark, treatment guidelines for use in swine production are currently under review at the Danish Veterinary and Food Administration. Use of pleuromutilins in swine has previously been associated with a very low risk for human health. However, recent international data and sporadic findings of novel resistance genes suggest a change of risk. Consequently, a reassessment was undertaken inspired by a risk assessment framework developed by the European Medicines Agency. Livestock-associated methicillin-resistant Staphylococcus aureus of clonal complex 398 (MRSA CC398) and enterococci were identified as relevant hazards. The release assessment showed that the probability of development of pleuromutilin resistance was high in MRSA CC398 (medium uncertainty) and low in enterococci (high uncertainty). A relatively small proportion of Danes has an occupational exposure to pigs, and foodborne transmission was only considered of relevance for enterococci, resulting in an altogether low exposure risk. The human consequences of infection with pleuromutilin-resistant MRSA CC398 or enterococci were assessed as low for the public in general but high for vulnerable groups such as hospitalized and immunocompromised persons. For MRSA CC398, the total risk was estimated as low (low uncertainty), among other due to the current guidelines on prevention of MRSA in place at Danish hospitals, which include screening of patients with daily contact to pigs on admittance. Moreover, MRSA CC398 has a medium human-human transmission potential. For enterococci, the total risk was estimated as low due to low prevalence of resistance, low probability of spread to humans, low virulence, but no screening of hospitalized patients, high ability of acquiring resistance genes, and a limited number of alternative antimicrobials (high uncertainty). This assessment reflects the current situation and should be repeated if pleuromutilin consumption increases substantially, resulting in increased prevalence of mobile, easily transmissible resistance mechanisms. Continuous monitoring of pleuromutilin resistance in selected human pathogens should therefore be considered. This also includes monitoring of linezolid resistance, since resistance mechanisms for pleuromutilins and oxazolidones are often coupled.

This study presents British farmers' perception of, and barriers to, implementing Salmonella control on pig farms. Four farms that had implemented interventions and their 33 close contacts (known to the intervention farmers) took part in interviews before (phase 1) and after (phase 2) intervention trials to assess the difference in perception over time. Their results were compared against those from nine randomly selected control farms. The hypothesis was that farms implementing interventions whether or not successful, would influence their close contacts' opinion over time. Based on a 'pathway to disease control' model, three intrinsic factors known to influence motivation - attitudes, social norms and self-efficacy - were evaluated. Farmers mentioned that successful interventions on a farm would attract their attention. The use of an appropriate communication strategy is therefore recommended to stimulate farmers' intent to implement control measures. Both before and after the intervention trials, all farmers had a positive attitude towards Salmonella control and felt that their peers and authorities were supportive of controlling Salmonella on farms. In phase 2, however, farmers were more likely to want to share the burden of control with other stakeholders along the food chain and their belief in self-efficacy had weakened. Whilst social norms were not associated with an intention to take action on control, a positive attitude towards Salmonella control and a belief in self-efficacy were more likely to result in an intent to control. In phase 2, farmers with an intent to implement an intervention appeared to have a greater, but not significant positive belief in self-efficacy (p=0.108). This study confirmed that farmers recognised their responsibility for controlling Salmonella in pork - even though their confidence in their ability to control Salmonella decreased over time - and believed that responsibility should be shared with the rest of the production chain. It showed that farmers trusted their veterinarian as a source of advice to guide them during the process of implementing change, though an increase in farms' Salmonella seroprevalence score (Zoonosis National Control Programme (ZNCP) score) especially for those with a low ZNCP score was also likely to influence their behaviour. Getting concrete feedback from customers or a tangible benefit from their action was a strong incentive especially for farms with a ZNCP score higher than 50%. The study also revealed a need to validate which measures are effective as farmers did not perceive that the current advised interventions were worth the additional effort., (Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.)

The epidemiology of an extended spectrum beta-lactamase Escherichia coli (CTX-M-15) was observed and described on a commercial dairy farm located in the United Kingdom. During 2008 longitudinal sampling of faecal pat samples from different cattle groups comprising milking and non-milking cows, calving cows, calves, and the environment was carried out. The proportion of CTX-M-15 E. coli positive samples was significantly (p<0.0.01) higher in milking cows (30.3%, CI(95%) 26.8; 33.8) than in the herd as a whole (17.0%, CI(95%) 14.9; 19.0). In 2008 95.6% of sampled calves tested positive for CTX-M-15 E. coli at two days of age. A more detailed investigation in 2009 revealed that cows and heifers were approximately eight times more likely to test positive in the 10 days after calving than the 9 days before (OR 7.6, CI(95%) 2.32; 24.9). The CTX-M15 E. coli was also readily isolated from the immediate calving pen environment, including the water troughs. A cyclic pattern was apparent where cows immediately after calving and as high yielders were highly positive, but where the prevalence decreased during the dry period. The increased prevalence of the CTX-M-15 E. coli in certain cattle groups and farm environments including calving pens suggested that husbandry, antimicrobial usage and hygiene may play a significant role on a farm with regards to the epidemiology of CTX-M-15. This may offer a practical opportunity to reduce further dissemination through good practice and hygiene around calving., (Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.)

Bovine neonatal pancytopenia (BNP; previously known as idiopathic haemorrhagic diathesis and commonly known as bleeding calf syndrome) is a novel haemorrhagic disease of young calves which has emerged in a number of European countries during recent years. Data were retrospectively collected during June to November 2010 for 56 case calves diagnosed with BNP between 17 March and 7 June of the same year. These were compared with 58 control calves randomly recruited from herds with no history of BNP. Multivariable logistic regression analysis showed that increased odds of a calf being a BNP case were associated with its dam having received PregSure® BVD (Pfizer Animal Health) vaccination prior to the birth of the calf (odds ratio (OR) 40.78, p<0.001) and its herd of origin being located in Scotland (OR 9.71, p = 0.006). Decreased odds of a calf being a BNP case were associated with the calf having been kept outside (OR 0.11, p = 0.006). The longer that a cattle herd had been established on the farm was also associated with decreased odds of a calf in that herd being a BNP case (OR 0.97, p = 0.011).

Improved understanding of the ecology and epidemiology of Campylobacter in the poultry farm environment is key to developing appropriate farm-based strategies for preventing flock colonization. The sources of Campylobacter causing broiler flock colonization were investigated on one poultry farm and its environment, from which samples were obtained on three occasions during each of 15 crop cycles. The farm was adjacent to a dairy farm, with which there was a shared concreted area and secondary entrance. There was considerable variation in the Campylobacter status of flocks at the various sampling times, at median ages of 20, 26, and 35 days, with 3 of the 15 flocks remaining negative at slaughter. Campylobacters were recoverable from various locations around the farm, even while the flock was Campylobacter negative, but the degree of environmental contamination increased substantially once the flock was positive. Molecular typing showed that strains from house surroundings and the dairy farm were similar to those subsequently detected in the flock and that several strains intermittently persisted through multiple crop cycles. The longitudinal nature of the study suggested that bovine fecal Campylobacter strains, initially recovered from the dairy yard, may subsequently colonize poultry. One such strain, despite being repeatedly recovered from the dairy areas, failed to colonize the concomitant flock during later crop cycles. The possibility of host adaptation of this strain was investigated with 16-day-old chickens experimentally exposed to this strain naturally present in, or spiked into, bovine feces. Although the birds became colonized by this infection model, the strain may preferentially infect cattle. The presence of Campylobacter genotypes in the external environment of the poultry farm, prior to their detection in broiler chickens, confirms the horizontal transmission of these bacteria into the flock and highlights the risk from multispecies farms.

The implementation of disease control programs on farms requires an act of behavioral change. This study presents a theoretical framework from behavioral science, combined with basic epidemiological principles to investigate and explain the control of zoonotic agents on cattle farms. A pathway to disease control model was adapted from existing models in behavioral science and human medicine. Field data was used to demonstrate the validity of the model to identify and explain motivational factors for implementation of disease control programs among English and Welsh cattle farmers. The field data consisted of interviews conducted with 43 farmers, which were analyzed to investigate the farmers' perception of responsibility for safe cattle produce as well as the intrinsic and extrinsic barriers that inhibited the implementation of a zoonotic control program on their farms. The model was used to illustrate barriers affecting the implementation process and to classify farmers according to their current level of zoonotic control at each stage within the model. Ordinal multivariable logistic regression was used to identify the motivators associated with different levels of implementation. Younger farmers and/or larger herds were more likely to place financial responsibility upon the industry rather than government and all but two farmers accepted a social responsibility for food safety within cattle production. In general, attitudes towards zoonotic control were positive, but approximately half the farmers showed no intent to control and were inhibited by non-supportive social norms and/or a lack of belief in self-efficacy. The remaining farmers showed intent to control, but had not implemented any structured control program due to external barriers including lack of knowledge and both cultural and economic pressure from society and industry. The farmers with no intent to adopt control measures identified their private veterinarian as the preferred motivator, whereas consumer-demand and financial rewards or penalties were significantly associated with farmers who intended to control.

Escherichia coli O157 and Campylobacter jejuni and Campylobacter coli are zoonotic pathogens originating from farm animals. Cattle are the main reservoir for E. coli O157 and also contribute to human cases of campylobacteriosis through contaminated milk, direct contact, and environmental contamination. Thirty groups of young cattle on 30 farms were observed for 7 months and sampled on 4 to 6 separate occasions for E. coli O157 and C. jejuni/coli to characterize shedding patterns and identify risk factors. The within herd prevalence of E. coli O157 per sampling occasion ranged from 0 to 60% (mean = 24%) and average Campylobacter spp. within herd prevalence was 47% ranging from 0 to 100%. The prevalence of E. coli O157-positive herds declined with a linear trend throughout the study from 100 to 38% (OR: 0.5, P < 0.01), whereas time in the study was not significantly associated with Campylobacter prevalence (P = 0.13). Larger herds were more likely to be positive with either or both agents, whereas the number of suckler calves on the farm reduced the risk of both organisms (OR: 0.4/0.6, P < 0.01). Poultry on the premises reduced the risk of E. coli O157, but was not associated with Campylobacter. Emptying and cleaning the water troughs more often than once monthly reduced the risk of detecting Campylobacter and cattle sourced by private water supplies were more likely to be Campylobacter positive. No drinking water management practices were associated with E. coli O157. The risk of detecting both organisms were almost five times higher when the cattle were housed indoors (OR: 4.9, P = 0.03).

Campylobacter jejuni and C. coli are the most prevalent causes of bacterial diarrhoea in most of the Western World. In Great Britain, the source remains unknown for the majority of cases, though poultry is considered the main source of infection. Molecular typing methods identify cattle as a potential source of a proportion of the non-source-attributed cases, mainly through direct contact, environmental contamination or milk, but little is known about the epidemiology of Campylobacter in cattle. A cross-sectional study was undertaken on young cattle 3-17 months of age on 56 cattle farms in England and Wales to identify association between the presence of C. jejuni and C. coli and farm characteristics and management practices. Campylobacter was detected on 62.5% of the farms and the presence of dairy cows (OR: 3.7, CI(95%): 1.2; 11.7), indoor housing (OR: 4.6, CI(95%): 1.8; 12.0), private water supply (OR: 2.5, CI(95%): 1.2; 5.4), presence of horses (OR: 3.2, CI(95%):1.5; 6.9) and feeding hay (OR: 2.9, CI(95%):1.6; 5.5) were associated with detection. The model's goodness-of-fit was improved when herd size was forced in the model without being statistically significant (p=0.34).

This study investigated the relationship between flock health and Campylobacter infection of housed commercial broilers in Great Britain. Thirty ceca were collected at slaughter from batches of broilers from 789 flocks, at either full or partial depopulation, between December 2003 and March 2006 and examined individually for Campylobacter by direct plating onto selective media. Management and health data were collected from each flock and included information on mortality or culling during rearing, the number of birds rejected for infectious or noninfectious causes at slaughter, the proportion of birds with digital dermatitis (also termed hock burn), and other general characteristics of the flock. Campylobacter spp. were isolated from 280 (35%) flocks. The relationship between bird health and welfare and Campylobacter status of flocks was assessed using random-effects logistic regression models, adjusting for region, month, year, and rearing regime. Campylobacter-positive batches of ceca were associated with higher levels of rejection due to infection (odds ratio [OR], 1.5; 95% confidence interval [CI(95%)], 0.98 to 2.30) and digital dermatitis (OR, 2.08; CI(95%), 1.20 to 3.61). Furthermore, higher levels of these conditions were also associated with the highest-level category of within-flock Campylobacter prevalence (70 to 100%). These results could indicate that improving health and welfare may also reduce Campylobacter in broilers.

Verocytotoxin-producing Escherichia coli O157 (VTEC O157) may cause severe illness in people. Cattle are regarded as an important source of VTEC O157, and in an outbreak investigation, there is a necessity to establish whether or not the putative contact herd shares infection with the human case. The effectiveness of a herd investigation is impacted by the number of samples required, which will influence the time taken to collect samples and then process these in the laboratory. The objective of this study was to investigate the effectiveness of pooled sampling for detecting VTEC O157 in cattle herds in the United Kingdom. On farm 1, 150 individual fecal samples were collected during the course of a VTEC O157 outbreak investigation. One-gram and 10-g subsamples were tested from each individual sample. Once the culture results of the individual sample were known, pools comprising 5 and 10 individual samples were formed, with each pool containing a known number of positive samples. This data showed that the sensitivity of pooled sampling depended upon the proportion of positive samples in the pool. Further samples were collected from 2 more infected farms (2 and 3). Each individual sample was tested in duplicate. Pools of 5 feces were formed on-farm, and half the number of pooled feces were tested as individual feces. There was no significant difference between the number of cultures required for pooled sampling, as was the same for individual sampling, and therefore pooling did not improve the effectiveness of detection of VTEC O157.

A randomised controlled trial was used to investigate the effect of three complex management intervention packages to reduce the burden of E. coli O157 in groups of young-stock on cattle farms in England and Wales. All intervention farms were assigned measures to avoid buying in new animals and having direct contact or sharing water sources with other cattle. Furthermore, package A (7 farms) aimed to keep a clean environment and closed groups of young-stock; package B (14 farms) aimed for improved water and feed hygiene, whilst package C was assigned both A and B. The control farms (26 farms) were asked not to alter their practices. Farms, which were assigned intervention package A, exhibited a 48% reduction in E. coli O157 burden over the 4.5 months (average) of observation, compared to 18% on the control farms. The effect of package A compared to the control farms in a crude intention-to-treat model was RR = 0.26 (p=0.122). When the risk ratio was adjusted for actual application of the different measures, the effect of intervention package A became stronger and statistically significant (RR = 0.14 p=0.032). Statistical evidence (p< 0.05) showed that dry bedding and maintaining animals in the same groups were the most important measures within the package and weak evidence (p< 0.1) showed that a closed herd policy and no contact with other cattle may also be of importance. Compliance with the other measures in package A had no influence on the effect of the package. No evidence of effect of the other two intervention packages was found.

We conducted a cross-sectional study on 255 cattle farms in England and Wales to identify risk factors for verocytotoxin-producing E. coli O157 (VTEC). Exposure variables were collected at the levels of the farm and of the group of young-stock within the farms. On each farm a group of young-stock (6-18 months of age) was sampled to establish VTEC status. In our multiple logistic regression, farm VTEC status was associated with access to springs (OR: 0.31, CI95%: 0.12, 0.78) and assessing the wetness of the bedding material less frequently than daily (OR: 3.89 CI95%: 1.5, 10.2). At group-level we found no associated risk factors for animals housed outdoors in fields. Significant for groups housed in pens were wet bedding (wet OR: 3.43, CI95%: 1.3, 9.4; very wet OR: 4.24, CI95%: 1.2, 14.6), number of animals in the group (10-15 OR: 2.72, CI95%: 0.75, 9.9, 16-24, OR: 3.78, CI95%: 1.2, 12.3; >25 OR: 3.78, CI95%: 1.1, 12.7) and feeding straw (OR: 2.29, CI95%: 1.2, 5.5).