Dissemination of Multidrug-Resistant Commensal Escherichia coli in Feedlot Lambs in Southeastern Brazil. - Related Documents




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161401.0000Dissemination of Multidrug-Resistant Commensal Escherichia coli in Feedlot Lambs in Southeastern Brazil. Antimicrobial resistance (AR) is a public health issue since it limits the choices to treat infections by Escherichia coli in humans and animals. In Brazil, the ovine meat market has grown in recent years, but studies about AR in sheep are still scarce. Thus, this study aims to investigate the presence of AR in E. coli isolated from lambs during feedlot. To this end, feces from 112 lambs with 2 months of age, after weaning, were collected on the first day of the animals in the feedlot (day 0), and on the last day before slaughtering (day 42). Isolates were selected in MacConkey agar supplemented with 4 mg/L of ceftiofur and identified by biochemical methods. Isolates were submitted to an antimicrobial susceptibility test by disc-diffusion and PCR to investigate genes for phylogenetic group, virulence determinants and resistance to the several antimicrobial classes tested. The genetic localization of the bla genes detected was elucidated by S1-PFGE followed by Southern blot-hybridizations. The isolates were typed by XbaI-PFGE and MLST methods. Seventy-eight E. coli were isolated from 8/112 (7.1%) animals on day 0, and from 55/112 (49.1%) animals on day 42. Since only fimH was present in almost all E. coli (97.4%) as a virulence gene, and also 88.5% belonged to phylogroups B1 or A, we consider that isolates represent intestinal commensal bacteria. The dendrogram separated the 78 non-virulent isolates in seven clusters, two of which comprised 50 E. coli belonging to ST/CC 1727/446 or ST 3994 recovered on day 42 commonly harboring the genotype bla (CMY -2)-aac(3)-IIa -tetA-sul1-sul2-floR-cmlA. Special attention should be given to the presence of bla (CTX-M-15), a worldwide gene spread, and bla (CTX-M-14), a hitherto undetected gene in Enterobacteriaceae from food-producing animals in Brazil. Importantly, E. coli lineages and plasmids carrying bla genes detected here have already been reported as sources of infection in humans either from animals, food, or the environment, which raises public health concerns. Hence, two types of commensal E. coli carrying important AR genes clearly prevailed during feedlot, but lambs are also reservoirs of bacteria carrying important AR genes such as bla (CTX-M-14) and bla (CTX-M-15), mostly related to antimicrobial treatment failure.201931293542
161110.9999Molecular Typing of Enterobacteriaceae from Pig Holdings in North-Western Germany Reveals Extended- Spectrum and AmpC β-Lactamases Producing but no Carbapenem Resistant Ones. The increase of extended- spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) in humans and in food-producing animals is of public health concern. The latter could contribute to spreading of these bacteria or their resistance genes to humans. Several studies have reported the isolation of third generation cephalosporin resistant bacteria in livestock animals. However, the number of samples and the methodology used differ considerably between studies limiting comparability and prevalence assessment. In the present study, a total of 564 manure and dust samples were collected from 47 pig farms in Northern Germany and analysed to determine the prevalence of ESBL-E. Molecular typing and characterization of resistance genes was performed for all ESBL-E isolates. ESBL-E isolates were found in 55.3% of the farms. ESBL-Escherichia coli was found in 18.8% of the samples, ESBL-Klebsiella pneumoniae in 0.35%. The most prevalent ESBL genes among E. coli were CTX-M-1 like (68.9%), CTX-M-15 like (16%) and CTX-M-9 group (14.2%). In 20% of the latter two, also the OXA-1 like gene was found resulting in a combination of genes typical for isolates from humans. Genetic relation was found between isolates not only from the same, but also from different farms, with multilocus sequence type (ST) 10 being predominant among the E. coli isolates. In conclusion, we showed possible spread of ESBL-E between farms and the presence of resistance genes and STs previously shown to be associated with human isolates. Follow-up studies are required to monitor the extent and pathways of ESBL-E transmission between farms, animals and humans.201526225428
101220.9999Antimicrobial resistance profile and prevalence of extended-spectrum beta-lactamases (ESBL), AmpC beta-lactamases and colistin resistance (mcr) genes in Escherichia coli from swine between 1999 and 2018. The frequent usage of antibiotics in livestock has led to the spread of resistant bacteria within animals and their products, with a global warning in public health and veterinarians to monitor such resistances. This study aimed to determine antibiotic resistance patterns and genes in pig farms from Spain during the last twenty years. Susceptibility to six antibiotics commonly used in pig production was tested by qualitative (disk diffusion) and quantitative (minimum inhibitory concentration, MIC) methods in 200 strains of Escherichia coli which had been isolated between 1999 and 2018 from clinical cases of diarrhoea in neonatal and post-weaned piglets. Results showed resistance around 100% for amoxicillin and tetracycline since 1999, and a progressive increase in ceftiofur resistance throughout the studied period. For colistin, it was detected a resistance peak (17.5% of the strains) in the 2011-2014 period. Concerning gentamicin, 11 of 30 strains with intermediate susceptibility by the disk diffusion method were resistant by MIC. Besides, the most frequent antimicrobial resistance genes were the extended-spectrum beta-lactamase (ESBL) bla (CTX-M) (13.5% of strains, being CTX-M-14, CTX-M-1 and CTX-M-32 the most prevalent genomes, followed by CTX-M-27, CTX-M-9 and CTX-M-3), AmpC-type beta-lactamase (AmpC) bla (CMY-2) (3%) and colistin resistance genes mcr-4 (13%), mcr-1 (7%) and in less proportion mcr-5 (3%). Interestingly, these mcr genes were already detected in strains isolated in 2000, more than a decade before their first description. However, poor concordance between the genotypic mcr profile and the phenotypical testing by MIC was found in this study. These results indicate that although being a current concern, resistance genes and therefore antimicrobial resistant phenotypes were already present in pig farms at the beginning of the century.202032266079
101330.9999Molecular detection and antimicrobial resistance profiles of Extended-Spectrum Beta-Lactamase (ESBL) producing Escherichia coli in broiler chicken farms in Malaysia. Antimicrobial resistance is one of the major public health threats globally. This challenge has been aggravated with the overuse and misuse of antibiotics in food animals and humans. The present study aimed to investigate the prevalence of Extended-Spectrum β-lactamase (ESBL) genes in Escherichia coli (E. coli) isolated from broiler chickens in Kelantan, Malaysia. A total of 320 cloacal swabs were collected from farms in different districts of Kelantan and were analyzed using routine bacteriology, antimicrobial susceptibility test, and molecular techniques for further identification and characterization of ESBL encoding genes. Based on PCR detection for the E. coli species-specific Pho gene, 30.3% (97/320) of isolates were confirmed as E. coli, and 84.5% (82/97) of the isolates were positive for at least one ESBL gene. Majority of the isolates, 62.9% (61/97) were harboring blaCTX-M followed by 45.4% (44/97) of blaTEM genes, while 16.5% (16/97) of the isolates were positive for both mcr-1 and ESBL genes. Overall, 93.8% (90/97) of the E. coli were resistant to three or more antimicrobials; indicating that the isolates were multi-drug resistance. 90.7% of multiple antibiotic resistance (MAR) index value greater than 0.2, would also suggest the isolates were from high-risk sources of contamination. The MLST result shows that the isolates are widely diverse. Our findings provide insight into the alarmingly high distribution of antimicrobial resistant bacteria, mainly ESBL producing E. coli in apparently healthy chickens indicating the role of food animals in the emergence and spread of antimicrobial resistance, and the potential public health threats it may pose.202337205716
114340.9999Antimicrobial Resistance and Virulence Profiles of mcr-1-Positive Escherichia coli Isolated from Swine Farms in Heilongjiang Province of China. ABSTRACT: The emergence and global distribution of the mcr-1 gene for colistin resistance have become a public concern because of threats to the role of colistin as the last line of defense against some bacteria. Because of the prevalence of mcr-1-positive Escherichia coli isolates in food animals, production of these animals has been regarded as one of the major sources of amplification and spread of mcr-1. In this study, 249 E. coli isolates were recovered from 300 fecal samples collected from swine farms in Heilongjiang Province, People's Republic of China. Susceptibility testing revealed that 186 (74.70%) of these isolates were colistin resistant, and 86 were positive for mcr-1. The mcr-1-positive isolates had extensive antimicrobial resistance profiles and additional resistance genes, including blaTEM, blaCTX-M, aac3-IV, tet(A), floR, sul1, sul2, sul3, and oqxAB. No mutations in genes pmrAB and mgrB were associated with colistin resistance. Phylogenetic group analysis revealed that the mcr-1-positive E. coli isolates belonged to groups A (52.33% of isolates), B1 (33.72%), B2 (5.81%), and D (8.14%). The prevalence of the virulence-associated genes iutA, iroN, fimH, vat, ompA, and traT was moderate. Seven mcr-1-positive isolates were identified as extraintestinal pathogenic. Among 20 mcr-1-positive E. coli isolates, multilocus sequence typing revealed that sequence type 10 was the most common (five isolates). The conjugation assays revealed that the majority of mcr-1 genes were transferable at frequencies of 7.05 × 10-7 to 7.57 × 10-4. The results of this study indicate the need for monitoring and minimizing the further dissemination of mcr-1 among E. coli isolates in food animals, particularly swine.202032730609
161350.9999Research note: Occurrence of mcr-encoded colistin resistance in Escherichia coli from pigs and pig farm workers in Vietnam. WHO considers colistin as a highest priority critically important drug for human health, and occurrence of colistin-resistant bacteria in livestock is of health concern. The current study determined occurrence of colistin-resistant Escherichia coli in pigs and workers at pig farms in Vietnam, and investigated the genetic background for resistance. Colistin-resistant E. coli were detected from pigs in 53/116 (45.7%) farms, and from workers taking care of the pigs in 21/94 (22.3%) farms. Colistin-resistant isolates showed MIC to colistin between 4-16 mg/L, they were multidrug resistant (99%) and resistance was caused by the presence of mcr-1 genes in 97/102 (95.1%) E. coli from pigs and in 31/34 (91.1%) isolates from humans. mcr-1 is considered a plasmid-encoded gene, but this was not confirmed in the current investigation. In total, one pig isolate carried both mcr-1 and mcr-3 genes, whereas mcr-2, mcr-4 and mcr-5 genes were not detected. Shared resistance profiles between pig and human isolates on the same farm was only observed in four farms. The study showed that commensal E. coli from pigs in Vietnam constitute a reservoir for colistin-resitant E. coli, however, further studies are needed to confirm that mcr genes are associated with plasmids and their importance for human health.202037333956
101960.9999First Report of OXA-48 and IMP Genes Among Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Isolates from Diarrheic Calves in Tunisia. Antimicrobial resistance is one of the most serious threats to human and animal health. Evidence suggests that the overuse of antimicrobial agents in animal production has led to the emergence and dissemination of multidrug-resistant isolates. The objective of this study was to assess the rate of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in calf feces and to characterize their resistance genes for antibiotics like beta-lactams and colistin, but also to determine their virulence genes. Fecal samples were collected from 100 diarrheic calves in the region of Bizerte, Tunisia. After isolation, E. coli isolates were screened for antimicrobial resistance against 21 antibiotics by the disc diffusion method. Characterization of β-lactamase genes and determination of associated resistance genes were performed by polymerase chain reaction. Among 71 E. coli isolates, 26 (36.6%) strains were ESBL-producing. Most of these isolates were multidrug-resistant (92.3%) and the most prevalent beta-lactamase genes detected were bla(CTX-M) (n = 26), bla(SHV) (n = 11), and bla(TEM) (n = 8), whereas only 1 isolate carried the bla(CMY) gene. In addition, resistance to carbapenems was detected in two isolates; one of them harbored both bla(OXA-48) and bla(IMP) genes and the other isolate carried only the bla(IMP) gene. Several resistance genes were identified for the first time in Tunisia from cases of diarrheic calves. Furthermore, to the best of our knowledge, this is the first report of detection and identification of carbapenem resistance genes and virulence genes from calves in North Africa. A high occurrence of antimicrobial resistance of E. coli recovered from fecal samples of calves with diarrhea was observed, highlighting the need for prudent use of antimicrobial agents in veterinary medicine to decrease the incidence of multidrug-resistant bacteria for both animals and humans.202336695709
114570.9999Abundance of Mobilized Colistin Resistance Gene (mcr-1) in Commensal Escherichia coli from Diverse Sources. Aims: Antimicrobial resistance (AMR) spreads not only by pathogenic but also by commensal bacteria, and the latter can become a reservoir for resistance genes. This study was aimed to investigate the AMR patterns along with the presence of mobilized colistin resistance (mcr) genes in commensal Escherichia coli circulating in chickens, farm environments, street foods, and human patients. Materials and Methods: By a cross-sectional survey, isolates obtained from 530 samples were tested for their AMR profiles against 9 antimicrobials. Minimum inhibitory concentration (MIC) of the phenotypically colistin-resistant isolates was determined and screened for a set of mcr genes followed by sequencing of mcr-1 gene in the multidrug-resistant (MDR) isolates. Results: A total of 313 E. coli strains were isolated and confirmed by polymerase chain reaction. Antimicrobial susceptibility testing revealed that about 98% (confidence interval [95% CI] 95-99) of the isolates were MDR, and 58% (95% CI 52-63) isolates exhibited resistance to colistin. MIC values of colistin against the isolates ranged from 4 to 64 mg/L. Except for human patients, 20.4% colistin-resistant isolates from other sources of isolation had mcr-1 gene. Conclusions: There is abundance of commensal MDR E. coli strains with the acquisition of mcr-1 gene circulating in chickens and farm environments in Bangladesh.202133909471
161680.9999Characterization of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Fresh Produce and Agricultural Environments in Korea. ABSTRACT: This study was conducted to characterize Escherichia coli strains and evaluate the spread of antimicrobial resistance among these strains from fresh produce and farm environments in Korea. We then conducted phenotypic and genetic studies on antimicrobial-resistant isolates. We determined the genetic epidemiological characteristics of isolates that produced extended-spectrum β-lactamase (ESBL) and confirmed plasmid transfer in isolates that carried blaCTX-M-type genes. E. coli strains were isolated from 8 samples of fresh produce and 152 samples from the farm environment collected from May 2014 to June 2016. Cephalosporin resistance was the most prevalent (61.8%) type of resistance among the isolates. Five ESBL-producing strains with high genetic homology with E. coli of human or livestock origin were identified. Lateral transfer of plasmids harboring blaCTX-M-type genes to transconjugants was successful. Two isolates from Chinese cabbage and from water samples collected from a nearby stream harbored the ISEcp1-blaCTX-M-55-orf477 operon and were confirmed as sequence type 1196 and the same type of plasmid replicon, suggesting that cross-contamination was highly likely. A high-risk clone of sequence type 69 (clonal complex 69) isolates was also recovered from the farm environment. This study provides genetic evidence that antimicrobial resistance factors in E. coli from farm environments originate in the clinic or in livestock, highlighting the fact that good agricultural practices in farming are important to inhibit the spread of antimicrobial resistance to bacteria on fresh produce.202032083678
101490.9999Contamination of retail market meat with extended-spectrum beta-lactamase genes in Vietnam. The contamination of retail meat with antibiotic-resistant bacteria poses a substantial public health risk because of the potential spread of these bacteria within communities. The contamination of retail meat with extended-spectrum beta-lactamase (ESBL)-producing bacteria was investigated in four cities in Vietnam using real-time PCR, employing ESBL marker genes. This method provides a more comprehensive assessment of ESBL-producing bacterial contamination in meat samples than culture-based methods because it directly detects resistance genes from the extracted sample DNA. Retail meats in Vietnam were substantially contaminated with ESBL genes [54 % (n = 46) and 48 % (n = 49) of chicken and pork samples, respectively]. No significant differences in ESBL gene detection rates were observed between chicken and pork. The most frequently detected ESBL gene was blaTEM, followed by blaSHV, whereas blaCTX-M was found in only 4-8 % of the samples. Ho Chi Minh City showed significantly higher contamination rates for both chicken and pork than those in other cities. ESBL-producing Escherichia coli strains were isolated from contaminated meat samples and genomically analyzed. All isolated strains carried blaCTX-M, with some harboring blaTEM, whereas blaSHV was not detected. Although IncFIB plasmids were prevalent among the ESBL-producing E. coli strains, the variability in resistance gene profiles suggested that the endemic spread of specific resistance gene-carrying plasmids was unlikely. Overall, these findings highlight the effectiveness of the ESBL gene detection method and the high levels of ESBL-producing E. coli in retail meat.202539827751
1618100.9999Molecular Characterization of Multidrug-Resistant Escherichia coli from Fecal Samples of Wild Animals. Antimicrobial resistance (AMR) surveillance in fecal Escherichia coli isolates from wildlife is crucial for monitoring the spread of this microorganism in the environment and for developing effective AMR control strategies. Wildlife can act as carriers of AMR bacteria and spread them to other wildlife, domestic animals, and humans; thus, they have public health implications. A total of 128 Escherichia coli isolates were obtained from 66 of 217 fecal samples obtained from different wild animals using media without antibiotic supplementation. Antibiograms were performed for 17 antibiotics to determine the phenotypic resistance profile in these isolates. Extended-spectrum β-lactamase (ESBL) production was tested using the double-disc synergy test, and 29 E. coli strains were selected for whole genome sequencing. In total, 22.1% of the wild animals tested carried multidrug-resistant E. coli isolates, and 0.93% (2/217) of these wild animals carried E. coli isolates with ESBL-encoding genes (bla(CTX-M-65), bla(CTX-M-55), and bla(EC-1982)). The E. coli isolates showed the highest resistance rates to ampicillin and were fully susceptible to amikacin, meropenem, ertapenem, and imipenem. Multiple resistance and virulence genes were detected, as well as different plasmids. The relatively high frequency of multidrug-resistant E. coli isolates in wildlife, with some of them being ESBL producers, raises some concern regarding the potential transmission of antibiotic-resistant bacteria among these animals. Gaining insights into antibiotic resistance patterns in wildlife can be vital in shaping conservation initiatives and developing effective strategies for responsible antibiotic use.202439453061
1009110.9999The resistance patterns and molecular characteristics of ESBL/AmpC-producing Escherichia coli from captive panda ecosystem in China. Escherichia coli (E. coli) plays an important ecological role, and is a useful bioindicator to recognize the evolution of resistance in human, animal and environment. Recently, extended-spectrum β-lactamases (ESBL) producing E.coli has posed a threat to public health. Generally, captive healthy giant pandas are not exposed to antibiotics; however, they still acquire antimicrobial resistant bacteria. In order to understand whether there is an exchange of resistance genes within the ecosystems of captive giant pandas, this study explored resistance characteristics of 330 commensal E. coli isolates from feces of giant pandas, the surroundings, and breeders. Isolates from different sources showed similar resistance phenotype, and ESBL/AmpC-producing isolates showed more profound resistance to antibiotics than non-ESBL/AmpC-producing isolates (P<0.05). Furthermore, the occurrence of broad-spectrum β-lactamase related resistance genes and colistin resistance genes was detected, and isolates phylogenetic typing and multilocus sequence typing (MLST) were applied in this study. Seven different β-lactamase resistance genes (bla(CTX-M-55), bla(CTX-M-15), bla(CTX-M-27), bla(CTX-M-65), bla(TEM-1), bla(OXA-1) and bla(CMY)) and mcr-1 were found in 68 ESBL/AmpC-producing isolates. bla(CTX-M-55) (48.53 %) was found the most predominant resistance genes, followed by bla(TEM-1) (19.12 %) and bla(CTX-M-27) (16.18 %). Nonetheless, bla(CTX-M-55) was commonly detected in the isolates from giant pandas (63.16 %), the surroundings (43.48 %), and breeders (33.33 %). However, there were no carbapenemase genes detected in this study. mcr-1 was harbored in only one isolate from giant panda. Forty-five tansconjugants were successfully obtained in the conjugation experiments. The presence of antimicrobial resistance and related resistance genes tested were observed in the transconjugants. The results indicated that 52.63 % of the isolates from giant panda 73.91 % of the isolates from surroundings, and 100 % of the isolates from breeders were phylogroup A. Total of 27 sequence types (ST) were recognized from the isolate by MLST and found that ST48 (19/68; 27.94 %) was the predominant ST type, especially in the isolates from giant pandas and the surroundings. In conclusion, commensal ESBL/AmpC-producing E. coli becomes a reservoir of ESBL resistance genes, which is a potential threaten to health of giant pandas. The interaction between giant pandas, surroundings and breeders contribute to development of resistant phenotypes and genotypes which might transfer across species or the surroundings easily; hence, strict monitoring based on a "One Health" approach is recommended.202438728939
1153120.9999Antimicrobial resistance, virulence factors and genetic diversity of Escherichia coli isolates from household water supply in Dhaka, Bangladesh. BACKGROUND: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. METHODOLOGY/PRINCIPAL FINDINGS: A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84) of the isolates were multi-drug(≥ 3 classes of antibiotics) resistant (MDR) and 26% (n = 22) of these were positive for extended spectrum β-lactamase (ESBL). Of the 22 ESBL-producers, 20 were positive for bla CTX-M-15, 7 for bla OXA-1-group (all had bla OXA-47) and 2 for bla CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16) of the isolates carried virulence gene(s) characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8) of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates. SIGNIFICANCE: Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in urban areas.201323573295
1020130.9999Prevalence and characteristics of Escherichia coli strains producing extended-spectrum β -lactamases in slaughtered animals in the Czech Republic. Resistance of bacteria to antibiotics is a global medical problem requiring close cooperation between veterinary and human physicians. Raw materials and foods of animal origin may be not only a source of pathogenic bacteria causing alimentary tract infections but also a source of bacteria with a dangerous extent of resistance to antibiotics, potentially entering the human food chain. This article presents results of the first study in the Czech Republic detecting the presence of Enterobacteriaceae-producing extended-spectrum b -lactamases (ESBLs) in swabs collected in slaughterhouses from surfaces of healthy animal carcasses. In 2012, swabs taken from pig (n = 166) and cattle (n = 140) carcass surfaces were analyzed. In 17 % of 53 studied slaughterhouses, ESBL-producing Escherichia coli strains were isolated. ESBLs were found in 11 and 4 % of porcine and bovine samples, respectively. Swabs collected from pigs yielded 18 ESBL-producing E. coli strains. The bla genes were found to encode production of CTX-M-1 group enzymes in 16 strains, SHV in one case, and both CTX-M-1-like and TEM in another case. In swabs taken from cattle, five ESBL-producing E. coli strains were isolated. In three cases, the bla genes for CTX-M-1-like production were identified; in two cases, genes for both CTX-M-1-like and TEM production were found. The similarity/identity of ESBL-positive isolates was compared by pulsed-field gel electrophoresis. This is the first report and characterization of the presence and nature of ESBL-producing E. coli in swabs collected from surfaces of healthy pig and cattle carcasses in slaughterhouses in the Czech Republic.201324112579
1622140.9999Antimicrobial Susceptibility and Frequency of bla and qnr Genes in Salmonella enterica Isolated from Slaughtered Pigs. Salmonella enterica is known as one of the most common foodborne pathogens worldwide. While salmonellosis is usually self-limiting, severe infections may require antimicrobial therapy. However, increasing resistance of Salmonella to antimicrobials, particularly fluoroquinolones and cephalosporins, is of utmost concern. The present study aimed to investigate the antimicrobial susceptibility of S. enterica isolated from pork, the major product in Philippine livestock production. Our results show that both the qnrS and the bla(TEM) antimicrobial resistance genes were present in 61.2% of the isolates. While qnrA (12.9%) and qnrB (39.3%) were found less frequently, co-carriage of bla(TEM) and one to three qnr subtypes was observed in 45.5% of the isolates. Co-carriage of bla(TEM) and bla(CTX-M) was also observed in 3.9% of the isolates. Antimicrobial susceptibility testing revealed that the majority of isolates were non-susceptible to ampicillin and trimethoprim/sulfamethoxazole, and 13.5% of the isolates were multidrug-resistant (MDR). MDR isolates belonged to either O:3,10, O:4, or an unidentified serogroup. High numbers of S. enterica carrying antimicrobial resistance genes (ARG), specifically the presence of isolates co-carrying resistance to both β-lactams and fluoroquinolones, raise a concern on antimicrobial use in the Philippine hog industry and on possible transmission of ARG to other bacteria.202134943653
1617150.9999Multidrug-resistant Escherichia coli from free-living pigeons (Columba livia): Insights into antibiotic environmental contamination and detection of resistance genes. Bacterial resistance is a public and one health problem. Free-living birds can be reservoirs of multidrug-resistant bacteria and resistance genes. This study aimed to characterize the antimicrobial resistance of Escherichia coli isolated from free-living urban pigeons (Columba livia) in South Brazil. Ninety-two animals were sampled, and one isolate was obtained from each one. The isolates were characterized, and the antimicrobial resistance profile and beta-lactam and colistin resistance genes were investigated. The isolates were classified as phylogroups B1 (35%), B2 (33%), A (16%) and D (16%), and 14% of the strains had the eae virulence gene. All isolates were resistant to at least one antimicrobial, and 63% of them were multidrug-resistant. Geographical location where the pigeons were captured and presence of the eae gene were associated with multidrug resistance. bla(VIM) and mcr-1 genes were detected in one and two isolates, respectively. This is the first report of these genes in E. coli of pigeons. The bla(VIM) -positive isolate was classified as Shiga toxin-producing E. coli, and the isolates with mcr-1 were classified as Enterohaemorrhagic E. coli and Enteropathogenic E. coli, which raise additional concerns related to public health since these are zoonotic pathotypes. The results reveal that pigeons carry multidrug-resistant pathogenic E. coli, which may interest public health. Nonetheless, further studies on whether these animals are sources of contamination for humans must be performed to understand their role in spreading antimicrobial resistance.202235569138
1011160.9999Mechanisms of cephalosporin resistance in indicator Escherichia coli isolated from food animals. Resistance to β-lactams is considered one of the major global problems and recently it became the most frequently studied topic in the area of antimicrobial resistance. The study was focused on phenotypic and genetic characterisation of commensal Escherichia coli (E. coli), including those producing cephalosporinases, isolated from gut flora of healthy slaughter animals. E. coli were cultured simultaneously on MacConkey agar (MCA) and cefotaxime supplemented MCA. The isolates were confirmed with ONPG and indol tube tests as well as PCR targeting uspA gene. Microbroth dilution method was applied for determination of Minimal Inhibitory Concentrations and interpreted according to EUCAST epidemiological cut-off values. Cephalosporin resistance phenotypes were defined by E-tests (BioMerieux) and relevant gene amplicons from selected strains were sequenced. A total of 298 E. coli isolates with cephalosporin resistance (ESC) found in 99 ones, were obtained from 318 cloacal or rectal swabs deriving from broilers, layers, turkeys, pigs and cattle. Both extended spectrum β-lactamase (ESBL) and ampC-cephalosporinase resistance phenotypes were noted in all tested animal species but cattle. At least one of the analysed genes was identified in 90 out of 99 cephalosporin-resistant isolates: bla(TEM) (n=44), bla(CMY) (n=38), bla(CTX-M) (n=33) and bla(SHV) (n=12). None of the phenotypes was identified in nine isolates. Sequencing of PCR products showed occurrence of ESBL-genes: bla(CTX-M-1/-61), bla(SHV-12), bla(TEM-1,-52/-92,-135) and ampC-gene bla(CMY-2). They were located on numerous and diverse plasmids and resistance transferability was proved by electroporation of bla(SHV-12) and bla(CTX-M-1/-61) located on X1 plasmids. Detection of cephalosporin resistant E. coli confirms the existence of resistance genes reservoir in farm animals and their possible spread (i.e. via IncX1 plasmids) to other bacteria including human and animal pathogens. The identified genetic background indicates on ecological aspects of selection and dissemination of cephalosporin resistance in E. coli isolated from food-producing animals rather than its potential role for public health threats.201626869096
1015170.9999Antimicrobial-resistant and extended-spectrum β-lactamase-producing Escherichia coli in raw cow's milk. The occurrence of antimicrobial-resistant bacteria is an important public health issue. The aim of this study was the monitoring of resistant Escherichia coli in raw cow's milk with a focus on the detection of extended-spectrum β-lactamase (ESBL)-producing strains. In total, 263 samples of raw milk from 40 farms were collected and investigated in 2010 to 2013 in the Czech Republic. Detection of E. coli was performed and evaluated according to ISO 16649-2, and antibiotic resistance was screened by the disk diffusion method. The presence of E. coli was detected in 243 (92.4%) samples. In total, 270 isolates were obtained. Resistance to β-lactam (31.8%) and tetracycline (13.0%) antibiotics was detected most often and also multiresistant strains (5.5%) were observed. E. coli isolates found to be resistant to β-lactam, tetracycline, and quinolone antibiotics were assayed by PCR to detect selected genes encoding those resistance mechanisms. In isolates in which any bla genes were detected, a double-disk synergy test was performed. ESBL production was confirmed in 2 (0.7%) isolates. The genetic analysis identified the presence of the blaCTX-M gene and other resistance genes (tet(B) and qnrB). Both ESBL-positive isolates originated from the same farm and had an identical pulsed-field gel electrophoresis profile. The findings of our study indicate that milk can be a reservoir of bacteria carrying resistance genes with a potential for spreading through the food chain.201525581180
2981180.9999Investigation of plasmid-mediated resistance in E. coli isolated from healthy and diarrheic sheep and goats. Escherichia coli is zoonotic bacteria and the emergence of antimicrobial-resistant strains becomes a critical issue in both human and animal health globally. This study was therefore aimed to investigate the plasmid-mediated resistance in E. coli strains isolated from healthy and diarrheic sheep and goats. A total of 234 fecal samples were obtained from 157 sheep (99 healthy and 58 diarrheic) and 77 goats (32 healthy and 45 diarrheic) for the isolation and identification of E. coli. Plasmid DNA was extracted using the alkaline lysis method. Phenotypic antibiotic susceptibility profiles were determined against the three classes of antimicrobials, which resistance is mediated by plasmids (Cephalosporins, Fluoroquinolone, and Aminoglycosides) using the disc-diffusion method. The frequency of plasmid-mediated resistance genes was investigated by PCR. A total of 159 E. coli strains harbored plasmids. The isolates antibiogram showed different patterns of resistance in both healthy and diarrheic animals. A total of (82; 51.5%) E. coli strains were multidrug-resistant. rmtB gene was detected in all Aminoglycoside-resistant E. coli, and the ESBL-producing E. coli possessed different CTX-M genes. Similarly, fluoroquinolone-resistant E. coli possessed different qnr genes. On the analysis of the gyrB gene sequence of fluoroquinolone-resistant E. coli, multiple point mutations were revealed. In conclusion, a high prevalence of E. coli with high resistance patterns to antimicrobials was revealed in the current study, in addition to a wide distribution of their resistance determinants. These findings highlight the importance of sheep and goats as reservoirs for the dissemination of MDR E. coli and resistance gene horizontal transfer.202032127753
1005190.9999Prevalence and Characterization of Beta-Lactam and Carbapenem-Resistant Bacteria Isolated from Organic Fresh Produce Retailed in Eastern Spain. Fresh fruits and vegetables are potential reservoirs for antimicrobial resistance determinants, but few studies have focused specifically on organic vegetables. The present study aimed to determine the presence of third-generation cephalosporin (3GC)- and carbapenem-resistant Gram-negative bacteria on fresh organic vegetables produced in the city of Valencia (Spain). Main expanded spectrum beta-lactamase (ESBL)- and carbapenemase-encoding genes were also detected in the isolates. One hundred and fifteen samples were analyzed using selective media supplemented with cefotaxime and meropenem. Resistance assays for twelve relevant antibiotics in medical use were performed using a disc diffusion test. A total of 161 isolates were tested. Overall, 33.5% presented multidrug resistance and 16.8% were resistant to all β-lactam antibiotics tested. Imipenem resistance was observed in 18% of isolates, and low resistance levels were found to ceftazidime and meropenem. Opportunistic pathogens such as Acinetobacter baumannii, Enterobacter spp., Raoultella sp., and Stenotrophomonas maltophilia were detected, all presenting high rates of resistance. PCR assays revealed bla(VIM) to be the most frequently isolated ESBL-encoding gene, followed by bla(TEM) and bla(OXA-48). These results confirm the potential of fresh vegetables to act as reservoirs for 3GC- and carbapenem-producing ARB. Further studies must be carried out to determine the impact of raw organic food on the spread of AMRs into the community.202336830297