Assessing the Feasibility of a Two-Cohort Design to Assess the Potential of Homeopathic Medicinal Products to Reduce Antimicrobial Resistance in Turkeys (The HOMAMR Project)-Study Protocol.

BACKGROUND: Antimicrobial resistance (AMR) is a serious public health concern worldwide. The European Union requires a reduction in the use of antibiotics by 50% by 2030, with separate regulations on organic production that give preference to homeopathy and phytotherapy in organic farms before the use of conventional medicines (including antibiotics). We have therefore designed a two-phased project whose overarching aim is to investigate the potential role of homeopathic medicinal products (HMPs) in combating AMR in turkeys (the HOMAMR project): a two-cohort feasibility study using turkey-farm data that have been collected and analyzed retrospectively, followed by a prospective two-cohort study in turkey farms that would examine the impact of HMPs on changing antibiotic use. OBJECTIVE: The objective of this paper is to describe the protocol for the first phase of HOMAMR, which is a study under field conditions to assess the feasibility of collecting data retrospectively about turkeys that have been managed conventionally only or with HMPs. METHODS: Surveys performed on farms in Germany and Austria, including interviews with consenting farmers, will determine the feasibility of comparing retrospectively gathered data on antibiotic use and performance/production data in two cohorts of turkeys: (1) homeopathic treatment with conventional care (antibiotics) added if necessary or (2) conventional care (antibiotics) only. Co-primary outcomes to be studied are the amount of antimicrobial use and production period-related mortality. In addition, other production/performance parameters will be compared between the two treated cohorts. CONCLUSION: To our knowledge, this is the first feasibility study on the treatment of turkeys using homeopathy, and whose retrospectively obtained data will inform a prospective study that would examine the impact of HMPs on antibiotic use in commercial turkey raising, fattening and breeding production.

Modeling of interventions for reducing external Enterobacteriaceae contamination of broiler carcasses during processing.

This article presents a mathematical model for the Enterobacteriaceae count on the surface of broiler chicken during slaughter and how it may be affected by different processing technologies. The model is based on a model originally developed for Campylobacter and has been adapted for Enterobacteriaceae using a Bayesian updating approach and hitherto unpublished data gathered from German abattoirs. The slaughter process in the model consists of five stages: input, scalding, defeathering, evisceration, washing, and chilling. The impact of various processing technologies along the broiler processing line on the Enterobacteriaceae count on the carcasses' surface has been determined from literature data. The model is implemented in the software R and equipped with a graphical user interface which allows interactively to choose among different processing technologies for each stage along the processing line. Based on the choice of processing technologies the model estimates the Enterobacteriaceae count on the surface of each broiler chicken at each stage of processing. This result is then compared to a so-called baseline model which simulates a processing line with a fixed set of processing technologies. The model calculations showed how even very effective removal of bacteria on the exterior of the carcass in a previous step will be undone by the cross-contamination with leaked feces, if feces contain high concentrations of bacteria.

Characterization of qnrB-carrying plasmids from ESBL- and non-ESBL-producing Escherichia coli.

BACKGROUND: Escherichia coli carrying clinically important antimicrobial resistances [i.e., against extended-spectrum-beta-lactamases (ESBL)] are of high concern for human health and are increasingly detected worldwide. Worryingly, they are often identified as multidrug-resistant (MDR) isolates, frequently including resistances against quinolones/fluoroquinolones. RESULTS: Here, the occurrence and genetic basis of the fluoroquinolone resistance enhancing determinant qnrB in ESBL-/non-ESBL-producing E. coli was investigated. Overall, 33 qnrB-carrying isolates out of the annual German antimicrobial resistance (AMR) monitoring on commensal E. coli (incl. ESBL-/AmpC-producing E. coli) recovered from food and livestock between 2013 and 2018 were analysed in detail. Whole-genome sequencing, bioinformatics analyses and transferability evaluation was conducted to characterise the prevailing qnrB-associated plasmids. Furthermore, predominant qnrB-carrying plasmid-types were subjected to in silico genome reconstruction analysis. In general, the qnrB-carrying E. coli were found to be highly heterogenic in their multilocus sequence types (STs) and their phenotypic resistance profiles. Most of them appeared to be MDR and exhibited resistances against up to ten antimicrobials of different classes. With respect to qnrB-carrying plasmids, we found qnrB19 located on small Col440I plasmids to be most widespread among ESBL-producing E. coli from German livestock and food. This Col440I plasmid-type was found to be highly conserved by exhibiting qnrB19, a pspF operon and different genes of unassigned function. Furthermore, we detected plasmids of the incompatibility groups IncN and IncH as carriers of qnrB. All qnrB-carrying plasmids also exhibited virulence factors and various insertion sequences (IS). The majority of the qnrB-carrying plasmids were determined to be self-transmissible, indicating their possible contribution to the spread of resistances against (fluoro)quinolones and other antimicrobials. CONCLUSION: In this study, a diversity of different plasmid types carrying qnrB alone or in combination with other resistance determinants (i.e., beta-lactamase genes) were found. The spread of these plasmids, especially those carrying antimicrobial resistance genes against highest priority critically important antimicrobial agents, is highly unfavourable and can pose a threat for public health. Therefore, the dissemination pathways and evolution of these plasmids need to be further monitored.

Comparison of Antimicrobial Resistance of Thermophilic Campylobacter Isolates from Conventional and Organic Turkey Meat in Germany.

The objective of this study was to compare the prevalence and antimicrobial resistance (AMR) rates of Campylobacter spp. isolated from conventional and organic turkey meat sold at retail in Germany. Samples of conventional (N = 527) and organic (N = 245) fresh turkey meat without skin were collected at retail markets throughout Germany and tested for Campylobacter spp.. Campylobacter isolates were tested for resistance to six antimicrobials (gentamicin, streptomycin, ciprofloxacin, nalidixic acid, erythromycin, and tetracycline) using broth microdilution. Prevalence of Campylobacter spp. was higher in organic (32.7%) than in conventional (19.4%) turkey meat. The proportion of fully susceptible isolates was lower in Campylobacter coli (6.8%) than in Campylobacter jejuni (33.9%) and higher in isolates from organic (38.4%) than from conventional production (17.4%). Overall, resistance rates were the highest to ciprofloxacin, nalidixic acid, and tetracycline. Resistance to erythromycin was only observed in C. coli and resistance to gentamicin was absent. Overall, resistance rates to tetracycline and fluoroquinolones were higher in isolates from conventional (60.9% and 78.9%) than from organic meat (32.9% and 58.9%, respectively). However, this significant difference was only observed for C. jejuni, but not for C. coli. Further studies are needed to identify the reasons for the differences in the association of production type of turkeys with AMR in the different Campylobacter spp. and the critical parameters for the reduction of AMR in Campylobacter from turkey meat.

Relationship between the probability of veterinary-diagnosed bovine mastitis occurring and farm management risk factors on small dairy farms in Austria.

Bovine mastitis is the most frequently reported disease among dairy cows worldwide. Treatment of udder disease often involves the use of antimicrobial substances, which is difficult to justify with respect to their possible effect on the development and spread of antimicrobial resistance. Prevention of udder disease is therefore always preferable to treatment. The study presented here statistically analyzed the probability of mastitis occurring during 3,049 lactation periods on 208 farms and attempted to ascertain which on-farm management factors contributed to the occurrence of this udder disease in Austria. Farm management was assessed via online surveys completed by 211 farmers (211/251; response rate = 84.1%) as well as national milk performance recorders observing milking technique and herd veterinarians evaluating farm hygiene levels. Veterinary treatment records were used as a basis for mastitis reporting. The analysis was carried out using a generalized linear mixed model. The study population was not randomized but was part of a larger observational study. More than three fourths of the study farms were run conventionally, and the remainder were organic. Freestalls (and straw yards) made up 66% of the study population, and 34% of farms had tiestalls. Herd size ranged from 8 to 94 dairy cows (mean = 26.9; median = 21), with the most common breed (74% of all cows) being dual-purpose Simmental (Austrian Fleckvieh). A mastitis risk of 14.4% was reported via veterinary treatment records. The following factors were shown to be associated with a reduction in the risk of mastitis occurring: regular access to pasture (odds ratio, OR = 0.73), automatic milking machine shut-off (OR 0.67), and access to feed immediately after milking (OR = 0.43). Detrimental effects, which were likely to increase the probability of mastitis occurring, included lactation number (OR = 1.18), farming part time (OR = 1.55), and udders on the farm being classed by herd veterinarians as medium to severely soiled (OR = 1.47). The study presented here was able to confirm several management factors recommended to reduce the probability of mastitis occurring during a cow's lactation period, with particular relevance for the small dairy herds common to Austria.

Whole genome analyses of CMY-2-producing Escherichia coli isolates from humans, animals and food in Germany.

BACKGROUND: Resistance to 3rd-generation cephalosporins in Escherichia coli is mostly mediated by extended-spectrum beta-lactamases (ESBLs) or AmpC beta-lactamases. Besides overexpression of the species-specific chromosomal ampC gene, acquisition of plasmid-encoded ampC genes, e.g. blaCMY-2, has been described worldwide in E. coli from humans and animals. To investigate a possible transmission of blaCMY-2 along the food production chain, we conducted a next-generation sequencing (NGS)-based analysis of 164 CMY-2-producing E. coli isolates from humans, livestock animals and foodstuff from Germany. RESULTS: The data of the 164 sequenced isolates revealed 59 different sequence types (STs); the most prevalent ones were ST38 (n = 19), ST131 (n = 16) and ST117 (n = 13). Two STs were present in all reservoirs: ST131 (human n = 8; food n = 2; animal n = 6) and ST38 (human n = 3; animal n = 9; food n = 7). All but one CMY-2-producing ST131 isolates belonged to the clade B (fimH22) that differed substantially from the worldwide dominant CTX-M-15-producing clonal lineage ST131-O25b clade C (fimH30). Plasmid replicon types IncI1 (n = 61) and IncK (n = 72) were identified for the majority of blaCMY-2-carrying plasmids. Plasmid sequence comparisons showed a remarkable sequence identity, especially for IncK plasmids. Associations of replicon types and distinct STs were shown for IncK and ST57, ST429 and ST38 as well as for IncI1 and ST58. Additional ß-lactamase genes (blaTEM, blaCTX-M, blaOXA, blaSHV) were detected in 50% of the isolates, and twelve E. coli from chicken and retail chicken meat carried the colistin resistance gene mcr-1. CONCLUSION: We found isolates of distinct E. coli clonal lineages (ST131 and ST38) in all three reservoirs. However, a direct clonal relationship of isolates from food animals and humans was only noticeable for a few cases. The CMY-2-producing E. coli-ST131 represents a clonal lineage different from the CTX-M-15-producing ST131-O25b cluster. Apart from the ST-driven spread, plasmid-mediated spread, especially via IncI1 and IncK plasmids, likely plays an important role for emergence and transmission of blaCMY-2 between animals and humans.

Assessing changing weather and the El Niño Southern Oscillation impacts on cattle rabies outbreaks and mortality in Costa Rica (1985-2016).

BACKGROUND: Rabies is a major zoonotic disease affecting humans, domestic and wildlife mammals. Cattle are the most important domestic animals impacted by rabies virus in the New World, leading to thousands of cattle deaths per year and eliciting large economic losses. In the New World, virus transmission in cattle is primarily associated with Desmodus rotundus, the common vampire bat. This study analyses the association of weather fluctuations and the El Niño Southern Oscillation (ENSO), with the occurrence and magnitude, in terms of associated mortality, of cattle rabies outbreaks. Data from the 100 cattle rabies outbreaks recorded between 1985 and 2016 in Costa Rica were analyzed. Periodograms for time series of rabies outbreaks and the El Niño 4 index were estimated. Seasonality was studied using a seasonal boxplot. The association between epidemiological and climatic time series was studied via cross wavelet coherence analysis. Retrospective space-time scan cluster analyses were also performed. Finally, seasonal autoregressive time series models were fitted to study linear associations between monthly number of outbreaks, monthly mortality rates and the El Niño 4 index, temperature, and rainfall. RESULTS: Large rabies mortality occurred towards the Atlantic basin of the country. Outbreak occurrence and size were not directly associated with ENSO, but were sensitive to weather variables impacted by ENSO. Both, ENSO phases and rabies outbreaks, showed a similar 5 year period in their oscillations. Cattle rabies mortality and outbreak occurrence increased with temperature, whereas outbreak occurrence decreased with rainfall. These results suggest that special weather conditions might favor the occurrence of cattle rabies outbreaks. CONCLUSIONS: Further efforts are necessary to articulate the mechanisms underpinning the association between weather changes and cattle rabies outbreaks. One hypothesis is that exacerbation of cattle rabies outbreaks might be mediated by impacts of weather conditions on common vampire bat movement and access to food resources on its natural habitats. Further eco-epidemiological field studies could help to understand rabies virus transmission ecology, and to propose sound interventions to control this major veterinary public health problem.

Short communication: Methicillin-resistant Staphylococcus aureus in conventional and organic dairy herds in Germany.

Methicillin-resistant Staphylococcus aureus (MRSA) have been described repeatedly in dairy herds. In this study, we compared the prevalence and antimicrobial resistance of MRSA in bulk tank milk from conventional and organic dairy herds in Germany. Samples were collected from 372 conventional and 303 organic dairy herds throughout Germany. Bulk tank milk (25 mL) was tested for MRSA using an established double selective enrichment method. The MRSA isolates were typed using spa typing and tested for resistance to 19 antimicrobials using the broth microdilution method. Methicillin-resistant Staph. aureus was detected more frequently in bulk tank milk from conventional (9.7%) than from organic (1.7%) dairy herds. Herd size and region were associated with differences in prevalence. Most isolates (38/41) were from spa types associated with the livestock-associated clonal complex CC398. Isolates from conventional herds tended to be more resistant to antimicrobials; however, because of the limited number of isolates from organic herds, no statistical tests were performed. In conclusion, prevalence of MRSA in dairy herds in Germany seems to be increasing and is more prevalent in regions with high livestock density. Organic herds are also affected although at a lower level. Therefore, MRSA should be specifically included in biosecurity protocols for dairy herds, and effective control measures need to be investigated.

A Probabilistic Transmission Model for the Spread of Extended-Spectrum-ß-Lactamase and AmpC-ß-Lactamase-Producing Escherichia Coli in the Broiler Production Chain.

Direct contact between humans and live broilers, as well as the consumption of chicken meat, have been suggested as pathways for transmission of extended-spectrum-ß-lactamase (ESBL) and AmpC-ß-lactamase (AmpC)-producing Escherichia coli. One approach to design intervention strategies to control the transmission of such bacteria between animals and humans is to study the transmission pathways of such bacteria between the animals themselves. The rationale is that controlling the process of the underlying source, here transmission between animals, can provide hints on how to control a higher-level process, here the transmission between animals and humans. The focus of this article is the transmission of the above-mentioned bacteria between broilers and broiler flocks in meat production with regards to the establishment of possible intervention strategies to reduce the transfer of these bacteria between animals. The objective of this work is to design a mathematical transmission model describing the effects of vertical and horizontal bacterial transmission in the broiler production chain, from the parent generation to the slaughterhouse level. To achieve this objective, an existing transmission model for Campylobacter was adapted for the case of E. coli. The model keeps track of prevalence among flocks (flock prevalence) and of prevalence among animals within one flock (animal prevalence). Flock and animal prevalences show different dynamics in the model. While flock prevalence increases mainly through horizontal transmission in hatcheries, animal prevalence increases mainly at the broiler-fattening farm. Transports have rather small effects just as the vertical transmission from parents to chicks.

[Transmission pathways for resistant bacteria between animals and humans: antibiotics resistance in the One Health context]. / Übertragungswege resistenter Bakterien zwischen Tieren und Menschen und deren Bedeutung ­ Antibiotikaresistenz im One-Health-Kontext.

People and animals share the same environment and antibiotics are used in both. Thus, antibiotics resistance is a major common issue for human and veterinary medicine. The potential impact of antibiotics use in animals on resistance in humans is frequently the focus of debate. In this paper the transmission pathways of resistant bacteria between animals and humans are described and the question is addressed whether a reduction in antibiotics use in animals contributes to the improvement of the resistance situation in humans. Direct contact between humans and animals, transmission of bacteria via food, and indirect transmission via emissions in the environment and the subsequent exposure of humans via the environment are the major transmission routes to be considered. It can thus be established that the relevance of these various transmission routes varies significantly among bacterial species. Furthermore, despite numerous investigations, the exact significance of transmission pathways and the bacteria transferred for the resistance situation in humans cannot yet be precisely quantified. There is evidence that antibiotics use in animals fosters the spread of resistant organisms in animals. Recent studies also suggest that there might be a relationship between antibiotics use in animals and the occurrence of resistance in humans. However, this relationship is complex, and for a better understanding of it and the role of the various transmission pathways, further collaborative studies between veterinary and medical science are needed.

[Antibiotic consumption and antimicrobial resistance in human and veterinary medicine : An overview of established national surveillance systems in Germany]. / Antibiotikaverbrauch und Antibiotikaresistenz in der Human- und Veterinärmedizin : Überblick über die etablierten nationalen Surveillance-Systeme.

The German Antimicrobial Resistance Strategy (DART) assigns a key role in combatting and reducing the further development and spread of antimicrobial resistance to the setup and development of instruments for the monitoring and surveillance of antimicrobial resistance and antibiotic consumption. The strategy follows the One Health approach, which targets human and veterinary medicine alike. An ongoing collection of appropriate data on antimicrobial resistance and antibiotic consumption and its distribution in time and space, will provide the basis for the identification of problems, the deduction of interventions, and finally the evaluation of their effectiveness. This article presents an overview of established surveillance systems in human and veterinary medicine with a national scope, including those that enable Germany to meet its own legal commitments as well as those within European and international action plans.

Evidence for Human Adaptation and Foodborne Transmission of Livestock-Associated Methicillin-Resistant Staphylococcus aureus.

We investigated the evolution and epidemiology of a novel livestock-associated methicillin-resistant Staphylococcus aureus strain, which colonizes and infects urban-dwelling Danes even without a Danish animal reservoir. Genetic evidence suggests both poultry and human adaptation, with poultry meat implicated as a probable source.

A likelihood-based approach to identifying contaminated food products using sales data: performance and challenges.

Foodborne disease outbreaks of recent years demonstrate that due to increasingly interconnected supply chains these type of crisis situations have the potential to affect thousands of people, leading to significant healthcare costs, loss of revenue for food companies, and--in the worst cases--death. When a disease outbreak is detected, identifying the contaminated food quickly is vital to minimize suffering and limit economic losses. Here we present a likelihood-based approach that has the potential to accelerate the time needed to identify possibly contaminated food products, which is based on exploitation of food products sales data and the distribution of foodborne illness case reports. Using a real world food sales data set and artificially generated outbreak scenarios, we show that this method performs very well for contamination scenarios originating from a single "guilty" food product. As it is neither always possible nor necessary to identify the single offending product, the method has been extended such that it can be used as a binary classifier. With this extension it is possible to generate a set of potentially "guilty" products that contains the real outbreak source with very high accuracy. Furthermore we explore the patterns of food distributions that lead to "hard-to-identify" foods, the possibility of identifying these food groups a priori, and the extent to which the likelihood-based method can be used to quantify uncertainty. We find that high spatial correlation of sales data between products may be a useful indicator for "hard-to-identify" products.

Subgrouping of ESBL-producing Escherichia coli from animal and human sources: an approach to quantify the distribution of ESBL types between different reservoirs.

Escherichia (E.) coli producing extended-spectrum beta-lactamases (ESBLs) are an increasing problem for public health. The success of ESBLs may be due to spread of ESBL-producing bacterial clones, transfer of ESBL gene-carrying plasmids or exchange of ESBL encoding genes on mobile elements. This makes it difficult to identify transmission routes and sources for ESBL-producing bacteria. The objectives of this study were to compare the distribution of genotypic and phenotypic properties of E. coli isolates from different animal and human sources collected in studies in the scope of the national research project RESET. ESBL-producing E. coli from two longitudinal and four cross-sectional studies in broiler, swine and cattle farms, a cross-sectional and a case-control study in humans and diagnostic isolates from humans and animals were used. In the RESET consortium, all laboratories followed harmonized methodologies for antimicrobial susceptibility testing, confirmation of the ESBL phenotype, specific PCR assays for the detection of bla(TEM), bla(CTX), and bla(SHV) genes and sequence analysis of the complete ESBL gene as well as a multiplex PCR for the detection of the four major phylogenetic groups of E. coli. Most ESBL genes were found in both, human and non-human populations but quantitative differences for distinct ESBL-types were detectable. The enzymes CTX-M-1 (63.3% of all animal isolates, 29.3% of all human isolates), CTX-M-15 (17.7% vs. 48.0%) and CTX-M-14 (5.3% vs. 8.7%) were the most common ones. More than 70% of the animal isolates and more than 50% of the human isolates contained the broadly distributed ESBL genes bla(CTX-M-1), bla(CTX-M-15), or the combinations bla(SHV-12)+bla(TEM) or bla(CTX-M-1)+bla(TEM). While the majority of animal isolates carried bla(CTX-M-1) (37.5%) or the combination bla(CTX-M-1)+bla(TEM) (25.8%), this was the case for only 16.7% and 12.6%, respectively, of the human isolates. In contrast, 28.2% of the human isolates carried bla(CTX-M-15) compared to 10.8% of the animal isolates. When grouping data by ESBL types and phylogroups bla(CTX-M-1) genes, mostly combined with phylogroup A or B1, were detected frequently in all settings. In contrast, bla(CTX-M-15) genes common in human and animal populations were mainly combined with phylogroup A, but not with the more virulent phylogroup B2 with the exception of companion animals, where a few isolates were detectable. When E. coli subtype definition included ESBL types, phylogenetic grouping and antimicrobial susceptibility data, the proportion of isolates allocated to common clusters was markedly reduced. Nevertheless, relevant proportions of same subtypes were detected in isolates from the human and livestock and companion animal populations included in this study, suggesting exchange of bacteria or bacterial genes between these populations or a common reservoir. In addition, these results clearly showed that there is some similarity between ESBL genes, and bacterial properties in isolates from the different populations. Finally, our current approach provides good insight into common and population-specific clusters, which can be used as a basis for the selection of ESBL-producing isolates from interesting clusters for further detailed characterizations, e.g. by whole genome sequencing.

Feasibility study of veterinary antibiotic consumption in Germany--comparison of ADDs and UDDs by animal production type, antimicrobial class and indication.

BACKGROUND: Within a feasibility study the use of antibiotics in pigs and cattle was determined in 24 veterinary practices in Lower Saxony and on 66 farms in North Rhine-Westphalia in Germany. Focus was laid on the comparison of the Used Daily Doses (UDD) (dose per animal and day prescribed by the veterinarians) with the Defined Animal Daily Doses (ADD) (dose per animal and day calculated by means of recommended dosages and estimated live weights). RESULTS: For piglets and calves most of the UDD (50% and 46% of nUDD, respectively) were above the ADD (i.e. UDD/ADD-ratio above 1.25). Regarding sows, fattening pigs, dairy and beef cattle, most of the UDDs (49% to 65% of nUDD) were lower than the respective ADD (i.e. UDD/ADD-ratio below 0.8). In pigs, the UDDs of beta-lactams, fluoroquinolones and cephalosporins, and in cattle, those of macrolides and beta-lactams were often below the ADDs. Tetracyclines were frequently used above the recommended dose.Enteric diseases were more often treated below the recommended dose than respiratory diseases, possibly due to overestimation of the live weight (diarrhea in young animals, respiratory diseases in elder animals) and consequently overestimation of the recommended dose. CONCLUSION: Comparisons between UDD and ADD can be used to observe differences between antimicrobials and trends in the usage of antibiotics. But individual treatment comparisons of UDD and ADD must be interpreted carefully, because they may be due to lower live weights than estimated. Correlating such data with data on the occurrence of resistant bacteria in future may help to improve resistance prevention and control.

Comparison of metrics to assess antibiotic use in small ruminants at a university referral clinic between 2005 and 2019.

BACKGROUND: Monitoring antibiotic use is essential to provide a framework enabling veterinarians to use antibiotics prudently. METHODS: Electronic medical records from the University of Veterinary Medicine's Clinic for Ruminants in Vienna were analysed with respect to sheep and goat antibiotic doses administered over a 15-year period (2005-2019). Antibiotic use was assessed using total milligrams per kilogram (mg/kg), total milligrams, number of doses administered, defined daily doses (DDD) for cattle and estimated DDD for sheep. RESULTS: A total of 5113 antibiotic doses were recorded over the 15-year period. Urinary tract disorders required the highest number of doses administered per animal (mean 16.9; median 16.0). Antibiotic use patterns varied according to the metrics used for analysis. By mg/kg, the largest proportion of antibiotics administered were penicillin/streptomycin (43.0% of the total mg/kg), followed by tetracyclines (17.3%) and sulphonamide/trimethoprim combinations (15.2%). By number of doses administered, the most frequently used antibiotics were penicillins (excluding combinations with streptomycin) (33.9% of total number of doses administered), fluoroquinolones (25.1%), third/fourth-generation cephalosporins (13.6%) and penicillin/streptomycin (13.4%). LIMITATIONS: As the university clinic was a city-based referral centre, this analysis cannot be compared directly with antibiotic use in commercial herds or flocks. CONCLUSIONS: The considered choice of antibiotic use metrics is essential for an effective and meaningful analysis of the responsible use of antibiotics by veterinarians in practice.

Identification of cost-effective biosecurity measures to reduce Salmonella along the pork production chain.

The continued occurrence of salmonellosis cases in Europe attributed to the consumption of pork products highlights the importance of identifying cost-effective interventions. Certain biosecurity measures (BSMs) may be effective in reducing the prevalence of specific pathogens along the pork production chain and their presence in food products. The objective of this study was to identify pathogen-specific, cost-effective BSMs to reduce Salmonella at different stages of the pork production chain in two European countries - Austria (AT) and the United Kingdom (UK). For this purpose, a cost-benefit analysis was conducted based on the epidemiological output of an established quantitative microbiological risk assessment that simulated the implementation effect of the BSMs based on their risk ratios. For each of the BSMs, the associated costs and benefits were assessed individually and country-specifically. For both AT and UK, nine different BSMs were evaluated assuming a countrywide implementation rate of 100%. The results showed that four BSMs were cost-effective (benefit-cost ratio > 1) for AT and five for the UK. The uncertainty regarding the cost-effectiveness of the BSMs resulted from the variability of individual risk ratios, and the variability of benefits associated with the implementation of the BSMs. The low number of cost-effective BSMs highlights the need for holistic risk-based models and economic assessments. To increase the willingness to implement BSMs and maximize the benefits for stakeholders, who carry the majority of the implementation costs, epidemiological assessments of BSM effectiveness should consider the impact on several relevant pathogens simultaneously.

A One Health framework for exploring zoonotic interactions demonstrated through a case study.

The eco-epidemiology of zoonoses is often oversimplified to host-pathogen interactions while findings derived from global datasets are rarely directly transferable to smaller-scale contexts. Through a systematic literature search, we compiled a dataset of naturally occurring zoonotic interactions in Austria, spanning 1975-2022. We introduce the concept of zoonotic web to describe the complex relationships between zoonotic agents, their hosts, vectors, food, and environmental sources. The zoonotic web was explored through network analysis. After controlling for research effort, we demonstrate that, within the projected unipartite source-source network of zoonotic agent sharing, the most influential zoonotic sources are human, cattle, chicken, and some meat products. Analysis of the One Health 3-cliques (triangular sets of nodes representing human, animal, and environment) confirms the increased probability of zoonotic spillover at human-cattle and human-food interfaces. We characterise six communities of zoonotic agent sharing, which assembly patterns are likely driven by highly connected infectious agents in the zoonotic web, proximity to human, and anthropogenic activities. Additionally, we report a frequency of emerging zoonotic diseases in Austria of one every six years. Here, we present a flexible network-based approach that offers insights into zoonotic transmission chains, facilitating the development of locally-relevant One Health strategies against zoonoses.

Antimicrobial Resistance Surveillance: Data Harmonisation and Data Selection within Secondary Data Use.

Resistance to last-resort antibiotics is a global threat to public health. Therefore, surveillance and monitoring systems for antimicrobial resistance should be established on a national and international scale. For the development of a One Health surveillance system, we collected exemplary data on carbapenem and colistin-resistant bacterial isolates from human, animal, food, and environmental sources. We pooled secondary data from routine screenings, hospital outbreak investigations, and studies on antimicrobial resistance. For a joint One Health evaluation, this study incorporates epidemiological metadata with phenotypic resistance information and molecular data on the isolate level. To harmonise the heterogeneous original information for the intended use, we developed a generic strategy. By defining and categorising variables, followed by plausibility checks, we created a catalogue for prospective data collections and applied it to our dataset, enabling us to perform preliminary descriptive statistical analyses. This study shows the complexity of data management using heterogeneous secondary data pools and gives an insight into the early stages of the development of an AMR surveillance programme using secondary data.

First isolation and genotyping of pathogenic Leptospira spp. from Austria.

Leptospirosis is a globally distributed zoonotic disease. The standard serological test, known as Microscopic Agglutination Test (MAT), requires the use of live Leptospira strains. To enhance its sensitivity and specificity, the usage of locally circulating strains is recommended. However, to date, no local strain is available from Austria. This study aimed to isolate circulating Leptospira strains from cattle in Austria to enhance the performances of the routine serological test for both humans and animals. We used a statistical approach combined with a comprehensive literature search to profile cattle with greater risk of leptospirosis infection and implemented a targeted sampling between November 2021 and October 2022. Urine and/or kidney tissue were sampled from 410 cattle considered at higher risk of infection. Samples were inoculated into EMJH-STAFF culture media within 2-6 h and a real-time PCR targeting the lipL32 gene was used to confirm the presence/absence of pathogenic Leptospira in each sample. Isolates were further characterised by core genome multilocus sequence typing (cgMLST). Nine out of 429 samples tested positive by PCR, from which three isolates were successfully cultured and identified as Leptospira borgpetersenii serogroup Sejroe serovar Hardjobovis, cgMLST cluster 40. This is the first report on the isolation and genotyping of local zoonotic Leptospira in Austria, which holds the potential for a significant improvement in diagnostic performance in the country. Although the local strain was identified as a cattle-adapted serovar, it possesses significant zoonotic implications. Furthermore, this study contributes to a better understanding of the epidemiology of leptospirosis in Europe.