Companion Animals as Potential Reservoirs of Antibiotic Resistant Diarrheagenic Escherichia coli in Shandong, China

Characteristics of MDR E. coli strains isolated from Pet Dogs with clinic diarrhea: A pool of antibiotic resistance genes and virulence-associated genes

The increasing number of multi-drug resistant (MDR) bacteria in companion animals poses a threat to both pet treatment and public health. To investigate the characteristics of MDR Escherichia coli (E. coli) from dogs, we detected the antimicrobial resistance (AMR) of 135 E. coli isolates from diarrheal pet dogs by disc diffusion method (K-B method), and screened antibiotic resistance genes (ARGs), virulence-associated genes (VAGs), and population structure (phylogenetic groups and MLST) by polymerase chain reaction (PCR) for 74 MDR strains, then further analyzed the association between AMRs and ARGs or VAGs. Our results showed that 135 isolates exhibited high resistance to AMP (71.11%, 96/135), TET (62.22%, 84/135), and SXT (59.26%, 80/135). Additionally, 54.81% (74/135) of the isolates were identified as MDR E. coli. In 74 MDR strains, a total of 12 ARGs in 6 categories and 14 VAGs in 4 categories were observed, of which tetA (95.95%, 71/74) and fimC (100%, 74/74) were the most prevalent. Further analysis of associations between ARGs and AMRs or VAGs in MDR strains revealed 23 significant positive associated pairs were observed between ARGs and AMRs, while only 5 associated pairs were observed between ARGs and VAGs (3 positive associated pairs and 2 negative associated pairs). Results of population structure analysis showed that B2 and D groups were the prevalent phylogroups (90.54%, 67/74), and 74 MDR strains belonged to 42 STs (6 clonal complexes and 23 singletons), of which ST10 was the dominant lineage. Our findings indicated that MDR E. coli from pet dogs carry a high diversity of ARGs and VAGs, and were mostly belong to B2/D groups and ST10. Measures should be taken to prevent the transmission of MDR E. coli between companion animals and humans, as the fecal shedding of MDR E. coli from pet dogs may pose a threat to humans.

Characteristics, Whole-Genome Sequencing and Pathogenicity Analysis of Escherichia coli from a White Feather Broiler Farm

Avian colibacillosis, caused by avian Escherichia coli (E. coli), has historically been one of the most prevalent infectious diseases in large-scale poultry production, causing growth delays and mortality in chickens, resulting in huge economic losses. In recent years, the widespread use of antibiotics has led to the emergence of multidrug resistance in E. coli as a significant global problem and long-term challenge. Resistant E. coli can be transmitted to humans through animal products or the environment, which presents significant public health concerns and food safety issues. In this study, we analyzed the features of 135 E. coli strains obtained from a white feather broiler farm in Shandong, China, including antimicrobial susceptibility tests, detection of class 1 integrons, drug resistance genes, virulence genes, and phylogenetic subgroups. It is particularly worrying that all 135 E. coli strains were resistant to at least five antibiotic agents, and 100% of them were multidrug-resistant (MDR). Notably, the resistance genes of blaTEM, blaCTX-M, qnrS, aaC4, tetA, and tetB exhibited a high prevalence of carriage among the tested resistance genes. However, mcr-2~mcr-9 were not detected, while the prevalence of mcr-1 was found to be 2.96%. The most common virulence genes detected were EAST1 (14.07%, encoding enterotoxins) and fyuA (14.81%, encoding biofilm formation). Phylogenetic subgroup analysis revealed that E. coli belonging to groups B2 and D, which are commonly associated with high virulence, constituted 2.22% and 11.11%, respectively. The positive rate of class 1 integrons was 31.1%. Whole-genome sequencing (WGS) and animal experiments were performed on a unique isolated strain called 21EC78 with an extremely strong membrane-forming capacity. The WGS results showed that 21EC78 carried 11 drug resistance genes and 16 virulence genes. Animal experiments showed that intraperitoneal injection with 2 × 105 CFU could cause the death of one-day-old SPF chickens in 3 days. However, the mortality of Luhua chickens was comparatively lower than that of SPF chickens. This study reports the isolation of multidrug-resistant E. coli strains in poultry, which may pose a potential threat to human health via the food chain. Furthermore, the findings of this study enhance our comprehension of the frequency and characteristics of multidrug-resistant E. coli in poultry farms, emphasizing the urgent need for improved and effective continuous surveillance to control its dissemination.

Prevalence and characterization of antimicrobial-resistant Escherichia coli isolated from veterinary staff, pets, and pet owners in Thailand

BACKGROUND

Companion animals may act as antimicrobial resistance (AMR) reservoirs. This study investigated the prevalence and AMR patterns of Escherichia coli in pets and people in close contact with pets.

METHODS

A total of 955 samples were collected from veterinary clinics across Thailand by rectal and skin or ear swabs from dogs and cats and fecal swabs from veterinarians, veterinary assistants, and pet owners. The minimum inhibitory concentrations (MICs) of the obtained isolates were investigated using Sensititre™ MIC plates against 21 different antimicrobial drugs.

RESULTS

Escherichia coli from pets was frequently resistant to ampicillin (100%) and amoxicillin-clavulanic acid (100%), whereas E. coli from pet owners, veterinarians, and veterinary assistants was mostly resistant to tetracycline. The multiple antibiotic resistance index revealed that multidrug-resistant E. coli isolates were frequently found in dogs (34.92%), cats (62.12%), veterinarians (61.11%), veterinarian assistants (36.36%), and pet owners (47.62%). The most common AMR genes identified in this study were blaCTX-M, blaTEM, tetA, and tetB, which were associated with the antimicrobial susceptibility results. Additionally, extended-spectrum beta-lactamase (ESBL)-associated genes (i.e., blaCTX-M, blaTEM, and blaSHV) were found in 21.69%, 71.97%, 27.78%, and 21.43% of E. coli isolated from dogs, cats, veterinarians, and pet owners, respectively.

CONCLUSIONS

Our findings demonstrated the presence of AMR genes, particularly ESBL-associated genes, in E. coli isolated from healthy pets and veterinarians. This implies that these sources of E. coli could potentially be reservoirs for antibiotic resistance, thereby increasing the risk of harm to both humans and animals. These findings highlight the importance of implementing effective AMR control measures in veterinary practices, as bacteria resistant to commonly used antimicrobials are present in humans and animals.

Antibiotic Resistance Genes Carried by Commensal Escherichia coli from Shelter Cats in Italy

Antimicrobial resistance is a widespread global health problem. The presence of resistant bacteria and antibiotic resistance genes has been demonstrated not only in humans but also in animals, including pets. Stray cats share the urban environment with people and pets. This may facilitate transmission of resistant bacteria and resistance genes between stray animals, people and domestic animals. Several studies have investigated the role of stray cats as a fecal carrier of ESBL-producing bacteria. However, there are many genes and resistance mechanisms that can be detected in commensal E. coli, which, because of its genetic plasticity, is considered an indicator for monitoring antibiotic resistance. In this study, rectal swabs were collected from stray cats from colonies and shelters in the city of Monza (Monza Brianza, Italy) to isolate commensal E. coli. Phenotypic tests, such as the minimum inhibitory concentration (MIC) and the double disc test (DDST), and molecular analyses to detect antimicrobial resistance genes (ARGs) were used to study the resistance of these isolates. The results obtained confirm that stray cats can carry ESBL-producing E. coli (6.7%) and genes conferring resistance to other important antibiotic classes such as tetracyclines and sulfonamides.

Multidrug-Resistant Escherichia coli Strains to Last Resort Human Antibiotics Isolated from Healthy Companion Animals in Valencia Region

Failure in antibiotic therapies due to the increase in antimicrobial-resistant (AMR) bacteria is one of the main threats to public and animal health. In recent decades, the perception of companion animals has changed, from being considered as a work tool to a household member, creating a family bond and sharing spaces in their daily routine. Hence, the aim of this study is to assess the current epidemiological situation regarding the presence of AMR and multidrug resistance (MDR) in companion animals in the Valencia Region, using the indicator bacteria Escherichia coli as a sentinel. For this purpose, 244 samples of dogs and cats were collected from veterinary centres to assess antimicrobial susceptibility against a panel of 22 antibiotics with public health relevance. A total of 197 E. coli strains were isolated from asymptomatic dogs and cats. The results showed AMR against all the 22 antibiotics studied, including those critically important to human medicine. Moreover, almost 50% of the strains presented MDR. The present study revealed the importance of monitoring AMR and MDR trends in companion animals, as they could pose a risk due to the spread of AMR and its resistance genes to humans, other animals and the environment they cohabit.

Domestic cats are potential reservoirs of multidrug-resistant human enteropathogenic E. coli strains in Bangladesh

Companion animals serve as our best friends, confidants, and family members. Thus, disease and antibiotic resistance gene transmission in pets and humans must be sought out. The study aimed to identify the common pathogenic Escherichia coli (E.coli) in pet cats and the antibiotic resistance patterns and resistant gene distribution. Samples (n = 210) were collected from different veterinary clinics in Bangladesh's cities of Mymensingh and Dhaka. Pathogenic E. coli was identified using conventional and molecular approaches. The disc diffusion method assessed the resistance profile against 12 antibiotics, and PCR was used to identify the beta-lactam resistance genes. The prevalence of the stx-1 gene was found to be 2.86%, whereas the rfbO157 prevalence was found to be 1.90% in cats. The stx-1 gene (n = 6) was 100% resistant to erythromycin and imipenem, whereas 100% sensitive to chloramphenicol. In turn, the rfbO157 gene (n = 4) exhibited 100% resistance to erythromycin, imipenem, cefixime, and azithromycin. In addtion, we identified genes that exhibit resistance to beta-lactam antibiotics (100% blaTEM, 40% blaCTX-M, 40% blaSHV2). This study found shiga-toxin producing and extended-spectrum beta-lactamase (ESBL) producing E. coli for the first time in pet cats of Bangladesh. Furthermore, the antimicrobial resistance (AMR) profile of the isolated strains refers to the occurrence of multidrug, which concerns cats and their owners. The existence of these genes in non-diarrheic pet animal isolates indicates that domestic pets may serve as a reservoir for human infection. Thus, one health strategy comprising animal and human health sectors, governments, together with stakeholders is needed to confront multidrug-resistant E. coli infections in Bangladesh.

Epidemiology of companion animal AMR in the United States of America: filling a gap in the one health approach

Introduction

Antimicrobial resistance (AMR) is a global health concern that affects all aspects of the One Health Triad, including human, animal, and environmental health. Companion animals, such as cats and dogs, may contribute to the spread of AMR through their close contact with humans and the frequent prescription of antimicrobials. However, research on AMR in companion animals is limited, and there are few surveillance measures in place to monitor the spread of resistant pathogens in the United States.

Methods

This study aims to explore the practicality of using data from commercial laboratory antimicrobial susceptibility testing (AST) services for epidemiological analyses of AMR in companion animals in the United States.

Results

The study analyzed 25,147,300 individual AST results from cats and dogs submitted to a large commercial diagnostic laboratory in the United States between 2019 and 2021, and found that resistance to certain antimicrobials was common in both E. coli and S. pseudintermedius strains.

Conclusion

There has been a paucity of information regarding AMR in companion animals in comparison to human, environmental and other animal species. Commercial AST datasets may prove beneficial in providing more representation to companion animals within the One Health framework for AMR.

Prevalence and Risk Factors Associated with Multidrug Resistance and Extended-Spectrum β-lactamase Producing E. coli Isolated from Healthy and Diseased Cats

Household cats have been identified as potential antimicrobial resistance (AMR) reservoirs, and the extended-spectrum β-lactamases (ESBL) producing E. coli circulating among cats has been more frequently reported globally, but the factors linked to its colonization remain poorly understood. Thus, the objectives of this study were to determine E. coli shedding and the occurrence of multidrug resistant (MDR)- and ESBL-producing E. coli, as well as to determine risk factors associated with colonization of MDR and ESBL-producing E. coli isolated from both healthy and diseased cats in the Eastern Province of Saudi Arabia. In a cross-sectional study, 2000 swabs were collected from five anatomical regions (anus, skin, ear canal, nares, and conjunctival sac) of 209 healthy and 191 diseased cats that were admitted to a veterinary clinic in the Eastern Province of Saudi Arabia. In addition, each cat owner filled out a questionnaire about their cat's demographics, management, health status, and antimicrobial usage. E. coli was detected in 165 (41.3%) of all cats, including 59 (28.2%) healthy and 106 (55.5%) diseased cats. In total, 170 E. coli isolates were found in healthy (35.3%) and diseased (64.7%) cats. Susceptibility testing revealed that 123 (72.4%) of the E. coli isolates were resistant to at least one of the tested antimicrobials. Overall, 17.6% (30/170) of E. coli isolates were MDR, with 10 (5.9%) and 20 (11.8%) isolates found in healthy and diseased cats, respectively. However, only 12 (7.1%) E. coli isolates were resistant to cefotaxime and harbored the bla_CTX-M gene (ESBL-producer), with seven (4.1%) in healthy and five (2.9%) in diseased cats. Risk factor analysis showed that the odds of MDR and ESBL-producing E. coli were (20 and 17) and (six and eight) times higher when the family and cats were previously treated with antimicrobials, respectively. The presence of a child in the cat's family was also linked to an increased risk of MDR E. coli colonization (OR = 3.4). In conclusion, a high frequency of MDR and ESBL-producing E. coli was detected among healthy and diseased cats in Saudi Arabia, raising concerns about transmission to humans and supporting the need of a "One Health" approach to address the potential threats of cats as AMR reservoirs.

RB49-like Bacteriophages Recognize O Antigens as One of the Alternative Primary Receptors

The power of most of the enterobacterial O antigen types to provide robust protection against direct recognition of the cell surface by bacteriophage receptor-recognition proteins (RBP) has been recently recognized. The bacteriophages infecting O antigen producing strains of E. coli employ various strategies to tackle this nonspecific protection. T-even related phages, including RB49-like viruses, often have wide host ranges, being considered good candidates for use in phage therapy. However, the mechanisms by which these phages overcome the O antigen barrier remain unknown. We demonstrate here that RB49 and related phages Cognac49 and Whisky49 directly use certain types of O antigen as their primary receptors recognized by the virus long tail fibers (LTF) RBP gp38, so the O antigen becomes an attractant instead of an obstacle. Simultaneously to recognize multiple O antigen types, LTFs of each of these phages can bind to additional receptors, such as OmpA protein, enabling them to infect some rough strains of E. coli. We speculate that the mechanical force of the deployment of the short tail fibers (STF) triggered by the LTF binding to the O antigen or underneath of it, allows the receptor binding domains of STF to break through the O polysaccharide layer.

Distribution and Genomic Characterization of Third-Generation Cephalosporin-Resistant Escherichia coli Isolated from A Single Family and Home Environment: A 2-Year Longitudinal Study

Third-generation cephalosporin-resistant Escherichia coli (CREC), particularly strains producing extended-spectrum β-lactamases (ESBLs), are a global concern. Our study aims to longitudinally assemble the genomic characteristics of CREC isolates from fecal samples from an index patient with recurrent CREC-related urinary tract infections and his family and swabs from his home environment 12 times between 2019 and 2021 to investigate the distribution of antibiotic resistance genes. CREC identified using the VITEK 2 were subjected to nanopore whole-genome sequencing (WGS). The WGS of 27 CREC isolates discovered in 137 specimens (1 urine, 123 feces, and 13 environmental) revealed the predominance of ST101 and ST131. Among these sequence types, bla_CTX-M (44.4%, n = 12) was the predominant ESBL gene family, with bla_CTX-M-14 (n = 6) being the most common. The remaining 15 (55.6%) isolates harbored bla_CMY-2 genes and were clonally diverse. All E. coli isolated from the index patient’s initial urine and fecal samples belonged to O25b:H4-B2-ST131 and carried bla_CTX-M-14. The results of sequence analysis indicate plasmid-mediated household transmission of bla_CMY-2 or bla_CTX-M-55. A strong genomic similarity was discovered between fecal ESBL-producing E. coli and uropathogenic strains. Furthermore, bla_CMY-2 genes were widely distributed among the CREC isolated from family members and their home environment.