Investigation of plasmid-mediated resistance in E. coli isolated from healthy and diarrheic sheep and goats

Exploring Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Food-Producing Animals and Animal-Derived Foods

Antimicrobials serve as crucial treatments in both veterinary and human medicine, aiding in the control and prevention of infectious diseases. However, their misuse or overuse has led to the emergence of antimicrobial resistance, posing a significant threat to public health. This review focuses on extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in animals and their associated food products, which contribute to the proliferation of antimicrobial-resistant strains. Recent research has highlighted the presence of ESBL-producing E. coli in animals and animal-derived foods, with some studies indicating genetic similarities between these isolates and those found in human infections. This underscores the urgent need to address antimicrobial resistance as a pressing public health issue. More comprehensive studies are required to understand the evolving landscape of ESBLs and to develop strategic public health policies grounded in the One Health approach, aiming to control and mitigate their prevalence effectively.

Antimicrobial Resistance Characteristics of Fecal Escherichia coli and Enterococcus Species in U.S. Goats: 2019 National Animal Health Monitoring System Enteric Study

Escherichia coli and Enterococcus species are normal bacteria of the gastrointestinal tract and serve as indicator organisms for the epidemiology and emergence of antimicrobial resistance in their hosts and the environment. Some E. coli serovars, including E. coli O157:H7, are important human pathogens, although reservoir species such as goats remain asymptomatic. We describe the prevalence and antimicrobial resistance of generic E. coli, E. coli O157:H7, and Enterococcus species collected from a national surveillance study of goat feces as part of the National Animal Health Monitoring System (NAHMS) Goat 2019 study. Fecal samples were collected from 4918 goats on 332 operations across the United States. Expectedly, a high prevalence of E. coli (98.7%, 4850/4915) and Enterococcus species (94.8%, 4662/4918) was found. E. coli O157:H7 prevalence was low (0.2%; 10/4918). E. coli isolates, up to three per operation, were evaluated for antimicrobial susceptibility and 84.7% (571/674) were pansusceptible. Multidrug resistance (MDR; ≥3 classes) was uncommon among E. coli, occurring in 8.2% of isolates (55/674). Resistance toward seven antimicrobial classes was observed in a single isolate. Resistance to tetracycline alone (13.6%, 92/674) or to tetracycline, streptomycin, and sulfisoxazole (7.0% 47/674) was the most common pattern. All E. coli O157:H7 isolates were pansusceptible. Enterococcus isolates, up to four per operation, were prioritized by public health importance, including Enterococcus faecium and Enterococcus faecalis and evaluated. Resistance to lincomycin (93.8%, 1232/1313) was most common, with MDR detected in 29.5% (388/1313) of isolates. The combination of ciprofloxacin, lincomycin, and quinupristin resistance (27.1%, 105/388) was the most common pattern detected. Distribution and characteristics of antimicrobial resistance in E. coli and Enterococcus in the U.S. goat population from this study can inform stewardship considerations and public health efforts surrounding goats and their products.

Comparative prevalence of diarrheagenic Escherichia coli between children below five years with close contact to food animals in Kisumu County, Kenya

Introduction

diarrheal infections in young children below five years and food animals are caused by diarrheagenic Escherichia coli strains. The study focused on understanding the association between DEC pathotypes in children below five years and food animals to establish the possibility of zoonotic transmission.

Methods

samples from 150 children who presented with diarrhea at the Kisumu County Hospital and 100 stool samples from food animals were collected and processed using culture methods. Molecular identification of the pathotypes was assayed using a primer-specific polymerase chain reaction that targeted the six virulence genes related to the diarrheagenic Escherichia coli pathotypes.

Results

one hundred and fifty-six study subjects (100 children samples and 56 food animals) samples were positive for E. coli polymerase chain reaction detection revealed a prevalence of (23%) among children below five years and a prevalence of (20%) among the food animals. Children samples showed Enteroaggregative Escherichia coli, having high phenotypic frequency of (12%) followed by Enterotoxigenic Escherichia coli, (5.3%) and Enteropathogenic Escherichia (3.3%) the least being mixed infections Enteroaggregative/Enterotoxigenic Escherichia coli and Enteroaggregative/Enteropathogenic Escherichia coli with (1.3%) respectively. The food animals found in children homesteads were detected to harbor pathogenic strains of E. coli. Enteropathogenic Escherichia coli was the most prevalent pathotypes detected in cattle (13%) followed by Enterotoxigenic Escherichia coli detected in goats at (4%) and poultry at (3%).

Conclusion

presence of diarrheagenic Escherichia coli in food animals could serve as reservoirs of transmitting these bacteria to children below five years.

Evaluation of the antimicrobial attribute of bioactive peptides derived from colostrum whey fermented by Lactobacillus against diarrheagenic E. coli strains

Colostrum known as "liquid gold" contains approximately 60-80% of whey proteins that can be a great source of bioactive peptide production. Therefore, this study aimed to perform a comparative antimicrobial evaluation of the bioactive peptide generated from L. rhamnosus C25, L. rhamnosus C6, and L. casei NCDC17 fermented colostrum whey. Peptide fractions 10 kDa, 5 kDa, and 3 kDa were isolated using their respective molecular weight cut-off membranes and antimicrobial activity was evaluated against diarrheagenic E. coli strains. The higher inhibition was shown by < 10 kDa peptide fractions from L. rhamnosus C25 fermented colostrum whey and the zone of inhibition was 15 ± 0.06 (E. coli MTCC 723), 17 ± 0.04 (E. coli MTCC 724), 18 ± 0.05 (E. coli MTCC 725), and 17 ± 0.02 (E. coli ATCC 25922). In addition, ST-1 and LT-1 genes of E. coli strains were also confirmed using PCR which is responsible for the diarrheagenic property. Further, the interaction of potent peptides against E. coli strains was also observed by scanning electron microscope. Hence, the significance of the present study emphasized that these bioactive peptides generated from fermented colostrum whey can be used as ingredients in functional food against diarrhoea.

Antibiotic-Resistant Escherichia coli Strains Isolated from Captive Giant Pandas: A Reservoir of Antibiotic Resistance Genes and Virulence-Associated Genes

Recent studies showed that Escherichia coli (E. coli) strains isolated from captive giant pandas have serious resistance to antibiotics and carry various antibiotic resistance genes (ARGs). ARGs or virulence-associated genes (VAGs) carried by antibiotic-resistant E. coli are considered as a potential health threat to giant pandas, humans, other animals and the environment. In this study, we screened ARGs and VAGs in 84 antibiotic-resistant E. coli strains isolated from clinically healthy captive giant pandas, identified the association between ARGs and VAGs and analyzed the phylogenetic clustering of E. coli isolates. Our results showed that the most prevalent ARG in E. coli strains isolated from giant pandas is bla_TEM (100.00%, 84/84), while the most prevalent VAG is fimC (91.67%, 77/84). There was a significant positive association among 30 pairs of ARGs, of which the strongest was observed for sul1/tetC (OR, 133.33). A significant positive association was demonstrated among 14 pairs of VAGs, and the strongest was observed for fyuA/iroN (OR, 294.40). A positive association was also observed among 45 pairs of ARGs and VAGs, of which the strongest was sul1/eaeA (OR, 23.06). The association of ARGs and mobile gene elements (MGEs) was further analyzed, and the strongest was found for flor and intI1 (OR, 79.86). The result of phylogenetic clustering showed that the most prevalent group was group B2 (67.86%, 57/84), followed by group A (16.67%, 14/84), group D (9.52%, 8/84) and group B1 (5.95%, 5/84). This study implied that antibiotic-resistant E. coli isolated from captive giant pandas is a reservoir of ARGs and VAGs, and significant associations exist among ARGs, VAGs and MGEs. Monitoring ARGs, VAGs and MGEs carried by E. coli from giant pandas is beneficial for controlling the development of antimicrobial resistance.

Antimicrobial Resistance Pattern, Clustering Mechanisms and Correlation Matrix of Drug-Resistant Escherichia coli in Black Bengal Goats in West Bengal, India

A cross-sectional study covering four agro-climatic zones of West Bengal, India, was carried out to understand the risk-factors, antimicrobial resistance mechanism and clustering of the resistance characteristics of Escherichia coli isolated from healthy (170) and diarrhoeic (74) goats reared under intensive (52) and semi-intensive (192) farming practices. Of the 488 E. coli isolates, the majority, including the extended spectrum (n: 64, 13.11%) and AmpC β-lactamase (ACBL) (n: 86, 17.62%) producers, were resistant to tetracycline (25.2%), followed by enrofloxacin (24.5%), cefotaxime (21.5%) and amikacin (20.5%). Statistical modelling revealed that the isolates from diarrhoeic animals (p < 0.001) are likely to be more ACBL-positive than those from the healthy counterparts. Similarly, cefotaxime (p < 0.05) and enrofloxacin-resistance (p < 0.01) were significantly higher in diarrhoeic goats and in goats reared intensively. The isolates (n = 35) resistant to multiple drugs revealed the presence of β-lactamase [blaCTXM-1-(21), blaSHV-(7), blaTEM-(3), blaCMY-6-(1), blaCITM-(3)]; quinolone [qnrB-(10), qnrS-(7), aac(6’)-Ib-cr-(3)]; tetracycline [tetA-(19), tetB-(4)] and sulphonamide resistance determinants [sul1-(4)]; multiple plasmids, especially those belonging to the IncF and IncI1 replicon types; and active acrAB efflux pumps. Further, two isolates harbored the carbapenem resistance (blaNDM-5) gene and eight were strong biofilm producers. This first ever study conducted to unravel the status of AMR in goat farming reveals that not only the intensive farming practices but also certain clinical ailments such as diarrhoea can increase the shedding of the drug-resistant isolate. The emergence of multi-drug resistant (MDR) E. coli in goats, particularly those that are carbapenem resistant, is a cause for concern that indicates the spread of such pathogens even in the livestock sub-sector generally considered as naive.

Lactic Acid Bacteria from Gamecock and Goat Originating from Phitsanulok, Thailand: Isolation, Identification, Technological Properties and Probiotic Potential

From independent swab samples of the cloaca of indigenous gamecocks (CIG), anus of healthy baby goats (AHG), and vagina of goats (VG) originating from Phitsanulok, Thailand, a total of 263 isolates of lactic acid bacteria (LAB) were collected. Only three isolates, designated C707, G502, and V202, isolated from CIG, AHG, and VG, respectively, exhibited an excellent inhibitory zone diameter against foodborne pathogenic bacteria when evaluated by agar spot test. Isolates C707 and G502 were identified as Enterococcus faecium, whereas V202 was identified as Pediococcus acidilactici, based on 16S rRNA sequence analysis. When foodborne pathogenic bacteria were co-cultured with chosen LAB in mixed BHI-MRS broth at 39°C, their growth was suppressed. These LAB were found to be capable of surviving in simulated stomach conditions. Only the isolate G502 was able to survive in the conditions of simulated intestinal juice. This research suggests that selected LAB could be used as a food/feed supplement to reduce foodborne pathogenic bacteria and improve the safety of animal-based food or feed.

Gut Commensal Escherichia coli, a High-Risk Reservoir of Transferable Plasmid-Mediated Antimicrobial Resistance Traits

Background

Escherichia coli (E. coli), the main human gut microorganism, is one of the evolved superbugs because of acquiring antimicrobial resistance (AMR) determinants via horizontal gene transfer (HGT).

Purpose

This study aimed to screen isolates of gut commensal E. coli from healthy adult individuals for antimicrobial susceptibility and plasmid-mediated AMR encoding genes.

Methods

Gut commensal E. coli bacteria were isolated from fecal samples that were taken from healthy adult individuals and investigated phenotypically for their antimicrobial susceptibility against diverse classes of antimicrobials using the Kirby Bauer disc method. PCR-based molecular assays were carried out to detect diverse plasmid-carried AMR encoding genes and virulence genes of different E. coli pathotypes (eaeA, stx, ipaH, est, elt, aggR and pCVD432). The examined AMR genes were β-lactam resistance encoding genes (bla_CTX-M1, bla_TEM, bla_CMY-2), tetracycline resistance encoding genes (tetA, tetB), sulfonamides resistance encoding genes (sul1, sulII), aminoglycoside resistance encoding genes (aac(3)-II, aac(6′)-Ib-cr) and quinolones resistance encoding genes (qnrA, qnrB, qnrS).

Results

PCR results revealed the absence of pathotypes genes in 56 isolates that were considered gut commensal isolates. E. coli isolates showed high resistance rates against tested antimicrobial agents belonging to both β-lactams and sulfonamides (42/56, 75%) followed by quinolones (35/56, 62.5%), tetracyclines (31/56, 55.4%), while the lowest resistance rate was to aminoglycosides (24/56, 42.9%). Antimicrobial susceptibility profiles revealed that 64.3% of isolates were multidrug-resistant (MDR). High prevalence frequencies of plasmid-carried AMR genes were detected including bla_TEM (64%) sulI (60.7%), qnrA (51.8%), aac(3)-II (37.5%), and tetA (46.4%). All isolates harbored more than one gene with the most frequent genetic profile among isolates was bla_TEM-bla_CTX-M1-like-qnrA-qnrB-tetA-sulI.

Conclusion

Results are significant in the evaluation of plasmid-carried AMR genes in the human gut commensal E. coli, suggesting a potential human health risk and the necessity of strict regulation of the use of antibiotics in Egypt. Commensal E. coli bacteria may constitute a potential reservoir of AMR genes that can be transferred to other bacterial species.

Evidence of sheep and abattoir environment as important reservoirs of multidrug resistant Salmonella and extended-spectrum beta-lactamase Escherichia coli

The increase in antimicrobial-resistant (AMR) foodborne pathogens, including E. coli and Salmonella in animals, humans, and the environment, is a growing public health concern. Among animals, cattle, pigs, and chicken are reservoirs of these pathogens worldwide. There is a knowledge gap on the prevalence and AMR of foodborne pathogens in small ruminants (i.e., sheep and goats). This study investigates the prevalence and antimicrobial resistance of extended-spectrum beta-lactamase (ESBL) E. coli and Salmonella from sheep and their abattoir environment in North Carolina. We conducted a year-round serial cross-sectional study and collected a total of 1128 samples from sheep (n = 780) and their abattoir environment (n = 348). Sheep samples consisted of feces, cecal contents, carcass swabs, and abattoir resting area feces. Environmental samples consisted of soil samples, lairage swab, animal feed, and drinking water for animals. We used CHROMAgar EEC with 4 μg/ml of Cefotaxime for isolating ESBL E. coli, and ESBL production was confirmed by double-disk diffusion test. Salmonella was isolated and confirmed using standard methods. All of the confirmed isolates were tested against a panel of 14 antimicrobials to elucidate susceptibility profiles. The prevalence of ESBL E. coli and Salmonella was significantly higher in environmental samples (47.7% and 65.5%) compared to the sheep samples (19.5% and 17.9%), respectively (P < 0.0001). We recovered 318 ESBL E. coli and 368 Salmonella isolates from sheep and environmental samples. More than 97% (310/318) of ESBL E. coli were multidrug-resistant (MDR; resistant to ≥3 classes of antimicrobials). Most Salmonella isolates (77.2%, 284/368) were pansusceptible, and 10.1% (37/368) were MDR. We identified a total of 24 different Salmonella serotypes by whole genome sequencing (WGS). The most common serotypes were Agona (19.8%), Typhimurium (16.2%), Cannstatt (13.2%), Reading (13.2%), and Anatum (9.6%). Prevalence and percent resistance of ESBL E. coli and Salmonella isolates varied significantly by season and sample type (P < 0.0001). The co-existence of ESBL E. coli in the same sample was associated with increased percent resistance of Salmonella to Ampicillin, Chloramphenicol, Sulfisoxazole, Streptomycin, and Tetracycline. We presumed that the abattoir environment might have played a great role in the persistence and dissemination of resistant bacteria to sheep as they arrive at the abattoir. In conclusion, our study reaffirms that sheep and their abattoir environment act as important reservoirs of AMR ESBL E. coli and MDR Salmonella in the U.S. Further studies are required to determine associated public health risks.

High β-Lactam and Quinolone Resistance of Enterobacteriaceae from the Respiratory Tract of Sheep and Goat with Respiratory Disease

Simple Summary

β-lactams and quinolones are major groups of antibiotics that are commonly used for the treatment of severe infection both in animals and humans. Little is known about their resistance mechanisms in animals. Our results revealed high resistance rates against both groups in Gram-negative bacteria recovered from small ruminants suffering from respiratory disease. Phenotypically, 9.2% of the isolates were multidrug-resistant, and 11.8% and 6.6% of the isolates were positive for AmpC and ESBL production, respectively. Genetic characterization identified different β-lactamase-encoding genes such as bla_TEM, bla_SHV, and bla_CTX-M which are responsible for β-lactam resistance. Furthermore, the plasmid-mediated quinolone resistance gene, qnrS, was identified to be associated with quinolone resistance. Our results regenerate interest in the wise use of antimicrobials in animal fields as well as to apply a One Health approach to prevent and/or mitigate their dissemination to the human environment.

Abstract

During the last decade’s increase of antimicrobial resistance (AMR) in animals, animal-human transmission has become a major threat. Therefore, the present study aimed to evaluate the genetic basis of AMR in Gram-negative bacteria recovered from sheep and goats with respiratory disease. Nasal and ocular swabs were collected from 69 diseased animals, and 76 Gram-negative bacterial isolates were identified from 59 animals. All isolates were checked phenotypically for resistance and genotypically for different resistance mechanisms, including β-lactam, quinolone, and aminoglycoside resistance. Our results demonstrated that 9.2% (95% CI 4.5–17.8%) of the isolates were multidrug-resistant, with high resistance rates to β-lactams and quinolones, and 11.8% (95% CI 6.4–21%) and 6.6% (95% CI 2.8–14.5%) of the isolates were phenotypically positive for AmpC and ESBL, respectively. Genotypically, bla_TEM was the most identified β-lactamase encoding gene in 29% (95% CI 20–40%) of the isolates, followed by bla_SHV (14.5%, 95% CI 8.3–24.1%) and bla_CTX-M (4%, 95% CI 1.4–11%). Furthermore, 7.9% (95% CI 3.7–16.2%) of the isolates harbored plasmid-mediated quinolone resistance gene qnrS. Our study revealed for the first time to our knowledge high β-lactam and quinolone resistance associated with the bacteria recovered from sheep and one goat with respiratory disease. Furthermore, different antimicrobial resistant determinants were identified for the first time from animals in Africa, such as bla_LEN-13/55, bla_TEM-176 and bla_TEM-198/214. This study highlights the potential role of sheep and goats in disseminating AMR determinants and/or resistant bacteria to humans. The study regenerates interest for the development of a One Health approach to combat this formidable problem.

Plasmid-Mediated Antibiotic Resistant Escherichia coli in Sarawak Rivers and Aquaculture Farms, Northwest of Borneo

Background: The emergence of plasmid-mediated antibiotic resistance in Escherichia coli in water resources could pose a serious threat to public health. The study aims to investigate the dispersion of plasmid-mediated antibiotic-resistant E. coli from six rivers in Sarawak and two aquaculture farms in Borneo. Methods: A total of 74 water samples were collected for the determination of their bacteria colony count. An IMViC test identified 31 E. coli isolates and tested their susceptibility against twelve clinically important antibiotics. The extraction of plasmid DNA was done using alkali lysis SDS procedures. Characteristics, including plasmid copy number, molecular weight size, resistance rate and multiple antibiotic resistance (MAR), were assessed. Results: Our findings revealed that bacterial counts in rivers and aquaculture farms ranged from log 2.00 to 3.68 CFU/mL and log 1.70 to 5.48 cfu/mL, respectively. Resistance to piperacillin (100%) was observed in all E. coli; resistance to amoxicillin (100%) and ampicillin (100%) was observed in E. coli found in aquaculture farms; resistance to streptomycin (93%) was observed in E. coli found in rivers. All E. coli were resistant to ≥2 antibiotics and formed 26 MAR profiles, ranging from an index of 0.17 to 0.83, indicating that there are high risks of contamination. Some (48.4%) of the E. coli were detected with plasmids (1.2 to >10 kb), whereas 51.6% of the E. coli did not harbor any plasmids. The plasmid copy numbers reported were one plasmid (n = 7), two plasmids (n = 4), ≥ two plasmids (4). E. coli isolated from the Muara Tuang River showed the highest-molecular-weight plasmids. A statistical analysis revealed that there is no significant correlation (r = 0.21, p = 0.253) between the number of plasmids and the MAR index of the tested isolates. Conclusion: The distribution of MAR in E. coli from rivers is higher compared to the aquaculture environment. Our study suggests that MAR in isolates could be chromosome-mediated. Our results suggest that riverbed sediments could serve as reservoirs for MAR bacteria, including pathogens, under different climatic conditions, and their analysis could provide information for public health concerns.

Characterization of antibiotic resistance in Escherichia coli isolates from Black-headed gulls (Larus ridibundus) present in the city of Novi Sad, Serbia

Despite common resistance to antimicrobials in Escherichia coli isolates from farm animals in Serbia, no data are currently accessible on its occurrence in E. coli isolated from gulls. Therefore, 67 cloacal swabs and 70 fecal samples from black-headed gulls were investigated for the presence of antibiotic-resistant E. coli isolates. Ninety-nine isolates were obtained during the study. Resistotyping and resistance gene typing has shown that 44 isolates harbor resistance to one or more antibiotics. Multidrug resistance was detected in 24 E. coli isolates. Ten isolates were resistant to extended-spectrum cephalosporin antibiotics and were studied in detail including virulence gene typing, phylogenetic and multilocus sequence typing, and mating. These ten isolates belonged to phylogenetic groups B2 (five isolates), D (four isolates) and B1 (one isolate). Five different sequence types (ST38, ST2307, ST224, ST162 and ST34) were detected in E. coli isolates with AmpC phenotype and genotype. One isolate carried the Inc I2/FIB replicon type plasmid with the bla_CTX-M-1 gene. Nine isolates had bla_CMY-2 genes, which were detected on conjugative plasmids in seven isolates. The virulence genes hly, iroN, iss, ompT and cvaC were detected in one transconjugant. Ten isolates were found to be resistant to ciprofloxacin, whose MIC ranged from 4 to 32 mg/L. Genotyping revealed single or double mutations in the quinolone resistance determining region (QRDR) of the gyrA or gyrA, parC and parE genes, respectively. So, Black-headed gulls from Serbia may be colonized by multidrug-resistant E. coli, some of which are resistant to critically important antibiotics in medicine.