Antimicrobial Usage and Resistance in Companion Animals: A Cross-Sectional Study in Three European Countries

Antibiotic Resistant and Biofilm-Associated Escherichia coli Isolates from Diarrheic and Healthy Dogs

Bacteria isolated from companion animals are attracting concerns in a view of public health including antimicrobial resistance and biofilm development, both contributing to difficult-to-treat infections. The purpose of this study was to evaluate the minimum inhibitory concentrations (MIC) of 18 antibiotics in Escherichia coli isolated from two groups of dogs (healthy and diarrheic). Isolates were classified into phylogroups, examined for the presence of resistance genes and biofilm-formation capacity. In healthy dogs, phylogenetic analysis showed that 47.37% and 34.22% of E. coli isolates belonged to commensal groups (A; B1) in contrast to diarrheic dogs; 42.2% of isolates were identified as the B2 phylogroup, and these E. coli bacteria formed a stronger biofilm. The results of healthy dogs showed higher MIC levels for tetracycline (32 mg/L), ampicillin (64 mg/L), ciprofloxacin (8 mg/L) and trimethoprim-sulphonamide (8 mg/L) compared to clinical breakpoints. The most detected gene encoding plasmid-mediated resistance to quinolones in the healthy group was qnrB, and in dogs with diarrhea, qnrS. The resistance genes were more frequently detected in healthy dogs. The presence of the integron int1 and the transposon tn3 increases the possibility of transfer of many different cassette-associated antibiotic-resistance genes. These results suggest that dogs could be a potential reservoir of resistance genes.

Global prevalence and molecular characterization of extended-spectrum β-lactamase producing-Escherichia coli in dogs and cats - A scoping review and meta-analysis

Antimicrobial resistance (AMR) represents a major threat to human and animal health. Part of the AMR dimension is the circulation of extended-spectrum β-lactamases producing-Escherichia coli (ESBL-E. coli), which is now commonly reported among companion animals. However, the global perspective of the prevalence and population structure of ESBL-E. coli circulating in dogs and cats has not been estimated limiting our understanding of their role in the dissemination of ESBL-E. coli. The aim of this study was to compare the prevalence of ESBL-E. coli between dogs and cats and across countries through meta-analysis. We also performed a scoping review to summarize the current knowledge on ESBL genes and E. coli clones circulating among companion animals. A total of 128 studies published in PubMed, Web of Science, and Scopus up to April 2020 were selected and contained information on prevalence and/or molecular characterization of ESBL genes and ESBL-E. coli clones. Our review shows an increase in the number of publications between 2000 and 2019, concentrated mainly in Europe. Prevalence varied across continents, ranging from 0.63% (Oceania) to 16.56% (Africa) in dogs and from 0% (Oceania) to 16.82% (Asia) in cats. Although there were twice as many studies reporting prevalence on dogs (n = 61) than on cats (n = 32), and only 9 studies focused exclusively on cats, our meta-analysis showed no difference in the global prevalence of ESBL-E. coli between dogs (6.87% [95% CI: 4.46-10.45%]) and cats (5.04% [95% CI: 2.42-10.22%]). A considerable diversity of ESBL genes (n = 60) and sequence types (ST) (n = 171) were recovered from companion animals. ESBL-E. coli encoded by CTX-M-15 (67.5%, 77/114) and SHV-12 (21.9%, 25/114), along with resistant strains of ST38 (22.7%, 15/66) and ST131 (50%, 33/66) were widespread and detected in all continents. While presence of ESBL-E. coli is widespread, the drivers influencing the observed ESBL-E. coli prevalence and the clinical relevance in veterinary medicine and public health along with economic impact of ESBL-E. coli infections among companion animals need to be further investigated.

Development and Pilot of an Interactive Online Course on Antimicrobial Stewardship in Companion Animals

A holistic approach to antimicrobial use (AMU) and prescribing is needed to combat the problem of antimicrobial resistance (AMR). Previously, an antimicrobial stewardship programme (ASP) was developed, introduced, and evaluated in 44 Dutch companion animal clinics, which resulted in an optimization of AMU. As a follow-up to this, an online course was developed to promote awareness of AMU, AMR, and responsible antimicrobial prescribing. The aim of this paper is to describe the development and pilot, including evaluation, of this course, which will be disseminated more widely among Dutch companion animal veterinarians. The interactive programme consists of a major e-learning component and two online, face-to-face meetings. The course comprises five different parts corresponding with five consecutive weeks. Theory on several topics is offered, for example on AMU and AMR in general, Dutch regulations and guidelines on veterinary AMU, behavioural change, and possible methods to quantify AMU. Additionally, several assignments are offered, for example to reflect upon one’s own current antimicrobial prescribing behaviour. Interactive discussion and peer-to-peer learning are promoted. Since September 2020, the course has been offered in a pilot phase, and the feedback is promising. Evaluation of the pilot phase will result in recommendations for further optimization and dissemination.

Driving Laboratory Standardization of Bacterial Culture and Antimicrobial Susceptibility Testing in Veterinary Clinical Microbiology in Europe and Beyond

Globally, antimicrobial resistance is one of the most important public health challenges in which the clinical microbiology laboratory plays a critical role by providing guidance for antimicrobial treatment. Despite the recognition of its importance, there is still a real need for the standardized training of clinical microbiologists and harmonization of diagnostic procedures. This is particularly true for veterinary clinical microbiology, where additional challenges exist when microbiologists are trying to fulfill a professional role very similar to that of their colleagues working in human microbiology laboratories. The specific points that need addressing to improve the outputs of veterinary microbiology laboratories discussed here include (i) harmonization of methodologies used by veterinary laboratories for antimicrobial susceptibility testing (AST); (ii) specific guidelines for interpretation and reporting of AST results for animal pathogens; (iii) guidelines for detection of antimicrobial resistance mechanisms in animal isolates; (iv) standardization of diagnostic procedures for animal clinical specimens; and (v) the need to train more veterinary clinical microbiology specialists. However, there is now a plan to address these issues, led by the European Network for Optimization of Veterinary Antimicrobial Treatment (ENOVAT), which is bringing together experts in veterinary microbiology, pharmacology, epidemiology, and antimicrobial stewardship from Europe and wider afield. ENOVAT is aiming to work with project partners toward standardization and harmonization of laboratory methodologies and optimization of veterinary antimicrobial treatment. Ultimately, the project may provide a mechanism for standardization and harmonization of veterinary clinical microbiology methodologies that could then be used as a template for implementation at a wider international level.

ESBL-Producing Escherichia coli Carrying CTX-M Genes Circulating among Livestock, Dogs, and Wild Mammals in Small-Scale Farms of Central Chile

Antibiotic-resistant bacteria of critical importance for global health such as extended-spectrum beta-lactamases-producing (ESBL)-Escherichia coli have been detected in livestock, dogs, and wildlife worldwide. However, the dynamics of ESBL-E. coli between these animals remains poorly understood, particularly in small-scale farms of low and middle-income countries where contact between species can be frequent. We compared the prevalence of fecal carriage of ESBL-E. coli among 332 livestock (207 cows, 15 pigs, 60 horses, 40 sheep, 6 goats, 4 chickens), 82 dogs, and wildlife including 131 European rabbits, 30 rodents, and 12 Andean foxes sharing territory in peri-urban localities of central Chile. The prevalence was lower in livestock (3.0%) and wildlife (0.5%) compared to dogs (24%). Among 47 ESBL-E. coli isolates recovered, CTX-M-group 1 was the main ESBL genotype identified, followed by CTX-M-groups 2, 9, 8, and 25. ERIC-PCR showed no cluster of E. coli clones by either host species nor locality. To our knowledge, this is the first report of ESBL-E. coli among sheep, cattle, dogs, and rodents of Chile, confirming their fecal carriage among domestic and wild animals in small-scale farms. The high prevalence of ESBL-E. coli in dogs encourages further investigation on their role as potential reservoirs of this bacteria in agricultural settings.

Bacterial zoonoses transmitted by household pets and as reservoirs of antimicrobial resistant bacteria

Numerous individuals are committed to growing pet creatures like cats, dogs, and rats etc., pay care for them and as a result of this, there's a boost of their populace in advanced culture. The close interaction between family pets and individuals offers ideal conditions for bacterial transmission. Distinctive sorts of antimicrobial agents are exploited for animal husbandry and studies have revealed that many bacteria have attained confrontation against them viz., Staphylococcus intermedius, Escherichia coli, methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococci and multidrug-resistant Salmonella typhi etc. and a few of these are a prospective for zoonotic transmission. In the current review, the attention has been paid on how household pets, especially dogs disperse the antimicrobial resistance in contrast to that of food animals. A lot of evidences are accessible on food animals and nation-wide scrutiny programmes solely hub on food animals; therefore, for steerage antimicrobial use policy in small animal veterinary exercise as well as for gauging the chance of transmission of antimicrobial resistance to humans' statistics on pet animals are sincerely needed. Transmission of such organisms, especially pathogenic staphylococci, occurs between pets, owners, and veterinary staff, and pets can act as reservoirs of such bacteria; this may additionally have an impact on the use of antimicrobials in human medicine. There is a need to generate statistics concerning each the levels of carriage of such microorganism in pets and the risk factors associated with the switch of the microorganism to human beings who have contact with infected pets, as nicely as to improve hygiene measures in veterinary practice.

Antibiotic prescription practices and opinions regarding antimicrobial resistance among veterinarians in Kentucky, USA

Background

Inappropriate antimicrobial use (AMU) is a global concern. Opinions of veterinarians regarding AMU and its role in the development of antimicrobial resistance (AMR) may influence their prescription practices. It is important to understand these opinions, prescription practices and their potential impact on the development of AMR in order to guide efforts to curb the problem. Therefore, the objective of this study was to investigate the antimicrobial prescription practices and opinions of veterinarians in Kentucky regarding AMU and AMR.

Methods

This cross-sectional study used a 30-question survey questionnaire administered to veterinarians who were members of the Kentucky Veterinary Medical Association. Survey responses from 101 participants were included in the study. Descriptive statistics were computed and associations between categorical variables assessed using Chi-square or Fisher’s exact tests. Firth logistic models were used to investigate predictors of “Compliance with prescription policies” and “Cost of antimicrobial affects prescription decisions”.

Results

Almost all (93%) respondents indicated that improper AMU contributed to selection for AMR. A total of 52% of the respondents believed that antimicrobials were appropriately prescribed, while the remaining 48% believed that antimicrobials were inappropriately prescribed. Significant predictors of compliance with prescription policies were availability of prescription policy at the veterinary facility (Odds Ratio (OR) = 4.2; p<0.001) and over-prescription (OR = 0.35; p = 0.025). Similarly, significant predictors of cost of antimicrobials affecting prescription decisions were lack of post-graduate training (OR = 8.3; p = 0.008) and practice type, with large animal practices having significantly lower odds of the outcome (OR = 0.09; p = 0.004) than small animal practices.

Conclusion

Most veterinarians indicated that improper AMU contributed to selection for AMR. Since the odds of compliance with prescription policies were 4-times higher among veterinarians working at facilities that had prescription policies compared to those at facilities that didn’t, more veterinary facilities should be encouraged to adopt prescription policies to help improve compliance and reduce AMR. Veterinarians would also benefit from continued professional education to help improve prescription practices, antimicrobial stewardship and curb AMR.

Diversity and Risk Factors Associated with Multidrug and Methicillin-Resistant Staphylococci Isolated from Cats Admitted to a Veterinary Clinic in Eastern Province, Saudi Arabia

Understanding the distribution, antimicrobial resistance (AMR), and risk factors associated with multidrug-resistant (MDR) and methicillin-resistant staphylococci (MRS) isolated from cats admitted to veterinary clinics may decrease the risk of MDR and MRS transmission to humans and other cats. As such, the objectives of this study were to investigate the diversity in Staphylococcus spp. recovered from different anatomical locations in healthy and diseased cats and to determine the occurrence of MDR and MRS spp. as well as possible risk factors associated with colonization in these cats. Five swabs were collected from the anus, skin, ear canal, conjunctival sac, and nares of each cat (209 healthy and 191 diseased) admitted to a veterinary clinic in Eastern Province, Saudi Arabia, between January and December 2018. Prior to sample collection, cat owners completed a questionnaire collecting information on cat demographics, health status, management, and antimicrobial usage. In total, 179 Staphylococcus isolates were recovered from healthy (n = 71) and diseased (n = 108) cats, including 94 (52.5%) coagulase-positive staphylococci (CoPS), and 85 (47.5%) coagulase-negative staphylococci (CoNS). Five Staphylococcus spp. were identified, namely, Staphylococcus aureus, Staphylococcus pseudintermedius, Staphylococcus felis, Staphylococcus capitis, and Staphylococcus saprophyticus. Staphylococcus isolates were most commonly resistant to penicillin (56.4%) and ciprofloxacin (25.7%); however, no isolate was resistant to clindamycin. Thirty (16.8%) Staphylococcus spp. (24 S. aureus and 6 S. pseudintermedius) isolates were MDR, with resistance to up to six different antibiotic classes. Only 17 (9.5%) Staphylococcus spp. (15 methicillin-resistant S. aureus and 2 methicillin-resistant S. pseudintermedius) harbored the mecA gene. Risk factor analysis showed that cats with a history of antibiotic therapy, those raised mainly indoors with a child, and those who visit a veterinary clinic for treatment were at higher risk of MDR and MRS colonization. In conclusion, MDR and MRS were common in healthy and diseased cats in Saudi Arabia. Thus, an effective antimicrobial stewardship program and further studies using a One Health approach are required to investigate the role of cats as vectors for AMR transmission to humans.

Data on before and after the Traceability System of Veterinary Antimicrobial Prescriptions in Small Animals at the University Veterinary Teaching Hospital of Naples

Simple Summary

Veterinary electronic prescription (VEP) is mandatory by law, dated 20 November 2017, No. 167 (European Law 2017) Article 3, and has been implemented in Italy since April 2019. In this study, the consumption of antimicrobials before and after the mandatory use of VEP was analyzed at the Italian University Veterinary Teaching Hospital of Naples in order to understand how the traceability of antimicrobials influences veterinary prescriptions. The applicability and utility of VEP may present an effective surveillance strategy able to limit both the improper use of antimicrobials and the spread of multidrug-resistant pathogens, which have become a worrying threat both in veterinary and human medicine.

Abstract

Over recent decades, antimicrobial resistance has been considered one of the most relevant issues of public health. The aim of our study was to evaluate the differences related to the prescription of antimicrobials at the University Veterinary Teaching Hospital, before and after the mandatory use of veterinary electronic prescription (VEP). In particular, the consumption of antimicrobials was examined, especially taking into consideration the recommendations of prudent use. A comparison of data collected before and after the use of electronic prescription highlighted that during the period chosen for the study, the choice of antimicrobial molecules was appropriate, favoring those of “first” and “second line.” However, prescription and the use of some molecules not registered for veterinary medicine were observed in the period before VEP. Broad-spectrum antimicrobials, including penicillins with β-lactamase inhibitors, as well as first-generation cephalosporins and fluoroquinolones, were the most frequently prescribed compounds. There are few studies conducted in Italy aimed at investigating the use of antimicrobials in companion animals under field conditions and with particular regard to prudent use recommendations. This type of study underlines the importance of electronic medical recording in veterinary practice and, above all, its usefulness in monitoring the use of certain antimicrobial agents classified as of critical importance in human medicine.

Prevalence of Vancomycin-Resistant Enterococcus (VRE) in Companion Animals: The First Meta-Analysis and Systematic Review

Antimicrobial resistance in companion animals is a major public health concern worldwide due to the animals’ zoonotic potential and ability to act as a reservoir for resistant genes. We report on the first use of meta-analysis and a systematic review to analyze the prevalence of vancomycin-resistant Enterococcus (VRE) in companion animals. Databases such as MedLib, PubMed, Web of Science, Scopus, and Google Scholar were searched. The information was extracted by two independent reviewers and the results were reviewed by a third. Two reviewers independently assessed the study protocol using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist and the study quality using the Joanna Briggs Institute (JBI) critical appraisal checklist for prevalence data. OpenMeta analyst and comprehensive meta-analysis (CMA) were used for the meta-analysis. The random effect model was used, and publication bias was assessed using the Eggers test and funnel plot. Between-study heterogeneity was assessed, and the sources were analyzed using the leave-one-out meta-analysis, subgroup analysis and meta-regression. Twenty-two studies met the eligibility criteria, but because some studies reported the prevalence of VRE in more than one companion animal, they were considered as individual studies, and 35 studies were therefore added to the final meta-analysis. Sampling period of the included studies was from 1995–2018. Of the 4288 isolates tested in the included studies, 1241 were VRE. The pooled prevalence of VRE in companion animals was estimated at 14.6% (95% CI; 8.7–23.5%; I² = 97.10%; p < 0.001). Between-study variability was high (t² = 2.859; heterogeneity I² = 97.10% with heterogeneity chi-square (Q) = 1173.346, degrees of freedom (df) = 34, and p < 0.001). The funnel plot showed bias, which was confirmed by Eggers test (t-value = 3.97165; p = 0.00036), and estimates from the leave-one-out forest plot did not affect the pooled prevalence. Pooled prevalence of VRE in dogs and cats were 18.2% (CI = 9.4–32.5%) and 12.3%, CI = 3.8–33.1%), respectively. More studies were reported in Europe than in any other continent, with most studies using feces as the sample type and disc diffusion as the detection method. With the emergence of resistant strains, new antimicrobials are required in veterinary medicine.

Impact of European pet antibiotic use on enterococci and staphylococci antimicrobial resistance and human health

Due to the inappropriate use of antibiotics described in both human and veterinary medicine, there is emerging evidence of antimicrobial-resistant organisms isolated from humans and pets, forming a multifaceted problem. Although the true magnitude of antimicrobial resistance in pets and other animals, as well as humans, are not fully known; pets, in particular dogs and cats, can contribute to the spread of antimicrobial resistance due to close contact with humans and their status as a family member in urban households. This review summarizes and highlights the current data concerning the antibiotic use on pets, and the European distribution of the increasing prevalence of multiresistant bacterial pathogens, such as enterococci and methicillin-resistant staphylococci on pets, as well as its implications for public health.

Insects, Rodents, and Pets as Reservoirs, Vectors, and Sentinels of Antimicrobial Resistance

This paper reviews the occurrence of antimicrobial resistance (AMR) in insects, rodents, and pets. Insects (e.g., houseflies, cockroaches), rodents (rats, mice), and pets (dogs, cats) act as reservoirs of AMR for first-line and last-resort antimicrobial agents. AMR proliferates in insects, rodents, and pets, and their skin and gut systems. Subsequently, insects, rodents, and pets act as vectors that disseminate AMR to humans via direct contact, human food contamination, and horizontal gene transfer. Thus, insects, rodents, and pets might act as sentinels or bioindicators of AMR. Human health risks are discussed, including those unique to low-income countries. Current evidence on human health risks is largely inferential and based on qualitative data, but comprehensive statistics based on quantitative microbial risk assessment (QMRA) are still lacking. Hence, tracing human health risks of AMR to insects, rodents, and pets, remains a challenge. To safeguard human health, mitigation measures are proposed, based on the one-health approach. Future research should include human health risk analysis using QMRA, and the application of in-silico techniques, genomics, network analysis, and ’big data’ analytical tools to understand the role of household insects, rodents, and pets in the persistence, circulation, and health risks of AMR.

Whole genome sequencing of coagulase positive staphylococci from a dog-and-owner screening survey

BACKGROUND

Staphylococcus aureus and S. pseudintermedius are the two most common coagulase positive staphylococci (CPS). S. aureus is more prevalent among humans, whereas S. pseudintermedius is more commonly isolated from dogs, however, both can cause various community and hospital acquired diseases in humans.

METHODS

In the current study we screened 102 dogs and 84 owners in Hungary. We tested the antibiotic susceptibility of the strains and in order to get a better picture of the clonal relationship of the strains, we used pulsed-field gel electrophoresis. In addition, three pairs of isolates with identical PFGE patterns were whole genome sequenced, MLST and spa types were established.

RESULTS

Carriage rate of S. aureus was 23.8% in humans and 4.9% in dogs and two cases of co-carriage were found among dogs and owners. S. pseudintermedius carriage rate was 2.4% and 34.3%, respectively, with only one co-carriage. The isolates were generally rather susceptible to the tested antibiotics, but high tetracycline resistance of S. pseudintermedius strains was noted. The co-carried isolates shared almost the same resistance genes (including tet(K), bla(Z), norA, mepR, lmrS, fosB) and virulence gene pattern. Apart from the common staphylococcal enzymes and cytotoxins, we found enterotoxins and exfoliative toxins as well. The two S. aureus pairs belonged to ST45-t630, ST45-t671 and ST15-t084, ST15-t084, respectively. The co-carried S. pseudintermedius isolates shared the same housekeeping gene alleles determining a novel sequence type ST1685.

CONCLUSIONS

Based on the genomic data, dog-owner co-carried strains displayed only insignificant differences therefore provided evidence for potential human-to-dog and dog-to-human transmission.

Quantifying Antimicrobial Exposure in Dogs From a Longitudinal Study

Bacterial resistance to antimicrobials (AMR) is a growing public health threat, and exposure to antimicrobials (AMs) is, on the whole, a major risk factor for the occurrence of AMR. During the past decade, a limited number of studies about AM exposure in dogs have been published, showing a noticeable diversity regarding numerators (AMU), denominators (population at risk), and indicators. The aim of this study is to show that metrics based on the most easily recorded data about treatments and a follow-up design are a promising method for a preliminary assessment of AM exposure in companion animals when more detailed data are not available. To quantify AM exposure, two simple indicators were used: the number of treatments (Ts) per 100 dogs and the number of treatments per 10 dog-years. Overall figures of AM exposure were 194 Ts/100_dogs (480 treatments and 248 dogs) and 18.4 Ts/10_dog-years (480 treatments and 95,171 dog-days), respectively. According to the administration route, AM exposure figures were 126 Ts/100 dogs (305 treatments and 242 dogs) and 12.1 Ts/10_dog-years (305 treatments and 92,059 dog-days) for systemic use and 66 Ts/100 dogs (160 treatments and 242 dogs) and 6.3 Ts/10_dog-years (160 treatments in 92,059 dog-days) for topical use. Since there is no current agreement regarding an indicator for quantifying AM exposure in dogs, in addition to other measures, the simplest indicators based on the most frequently available information should also be reported as a preliminary compromise for permitting a comparative analysis of the different scenarios.

Extended-Spectrum β-Lactamase-Producing Enterobacterales Shedding by Dogs and Cats Hospitalized in an Emergency and Critical Care Department of a Veterinary Teaching Hospital

Extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) gut shedding in human medicine is considered as a major reservoir for ESBL-associated infections in high risk patients. In veterinary medicine, data regarding ESBL-PE gut shedding on admission to emergency and critical care department is scarce. We aimed to determine ESBL-PE shedding rates by dogs and cats in this setting and to determine the risk factors for shedding, at two separate periods, three-years apart. Rectal swabs were collected from animals, on admission and 72 h post admission, enriched and plated on Chromagar ESBL plates, followed by bacterial identification. ESBL phenotype was confirmed and antibiotic susceptibility profiles were determined (Vitek 2). Medical records were reviewed for risk factor analysis (SPSS). Overall, 248 animals were sampled, including 108 animals on period I (2015-2016) and 140 animals on period II (2019). In both periods combined, 21.4% of animals shed ESBL-PE on admission, and shedding rates increased significantly during hospitalization (53.7%, p-value < 0.001). The main ESBL-PE species were Escherichia coli and Klebsiella pneumoniae, accounting for more than 85% of the isolates. In a multivariable analysis, previous hospitalization was a risk factor for ESBL-PE gut shedding (p-value = 0.01, Odds ratio = 3.05, 95% Confidence interval 1.28-7.27). Our findings demonstrate significant ESBL-PE gut shedding among small animals in the emergency and critical care department, posing the necessity to design and implement control measures to prevent transmission and optimize antibiotic therapy in this setting.

High Prevalence and Diversity of Cephalosporin-Resistant Enterobacteriaceae Including Extraintestinal Pathogenic E. coli CC648 Lineage in Rural and Urban Dogs in Northwest Spain

The aim of this work was to assess the prevalence of extended spectrum-β-lactamase (ESBL)- and carbapenemase-producing Enterobacteriaceae in fecal samples recovered from rural and urban healthy dogs in Northwest Spain (Galicia) to identify potential high-risk clones and to molecularly characterize positive isolates regarding the genes coding for ESBL/pAmpC resistance and virulence. Thirty-five (19.6%) out of 179 dogs were positive for cephalosporin-resistant Enterobacteriaceae, including Escherichiacoli and Klebsiella pneumoniae (39 and three isolates, respectively). All the isolates were multidrug resistant, with high rates of resistance to different drugs, including ciprofloxacin (71.4%). A wide diversity of ESBL/pAmpC enzymes, as well as E. coli phylogroups (A, B1, C, D, E, F and clade I) were found. The eight isolates (20.5%) found to conform to the ExPEC status, belonged to clones O1:H45-clade I-ST770 (CH11-552), O18:H11-A-ST93-CC168 (CH11-neg), O23:H16-B1-ST453-CC86 (CH6-31), and O83:H42-F-ST1485-CC648 (CH231-58), with the latter also complying the uropathogenic (UPEC) status. The three K. pneumoniae recovered produced CTX-M-15 and belonged to the ST307, a clone previously reported in human clinical isolates. Our study highlights the potential role of both rural and urban dogs as a reservoir of high-risk Enterobacteriaceae clones, such as the CC648 of E. coli and antimicrobial resistance traits. Within a One-Health approach, their surveillance should be a priority in the fight against antimicrobial resistance.

Staphylococcus nepalensis, a commensal of the oral microbiota of domestic cats, is a reservoir of transferrable antimicrobial resistance

Staphylococcus nepalensis is a commensal bacterium from the oral microbiota of domestic cats, with a still obscure clinical importance. In this work, we analysed the ability of feline strains of S. nepalensis to transfer antimicrobial resistance genes to Staphylococcus aureus isolated from humans through plasmids. To this end, we first analysed all publicly available genomes from cat staphylococci using computational methods to build a pan-resistome. Genes that encode resistance to erythromycin, gentamicin, mupirocin and tetracycline, common to human and cat staphylococci and previously described to be located in mobile genetic elements, were chosen for the next analyses. We studied 15 strains of S. nepalensis, which were shown to be genetically different by GTG₅-PCR. As observed by disc diffusion, resistance to tetracycline was widespread (80 %), followed by resistance to erythromycin (40 %), gentamicin (27 %) and mupirocin (7 %). The strains were positive for several antimicrobial resistance genes and more than half of them harboured plasmids. The loss of plasmids and resistance genes in some strains were induced by stress with SDS. Through conjugation experiments, we observed that these plasmids can be transferred to S. aureus, thus increasing its potential to resist drug therapy. Our findings show that S. nepalensis, an underestimated inhabitant of the cat microbiota, can be a reservoir of antimicrobial resistance genes for S. aureus and, like many other staphylococci, be an overlooked and silent threat to their animal hosts and humans living with them.