ESBL-producing Escherichia Coli Research Articles

High heterogeneity of fecal carriage extended-spectrum beta-lactamase-producing E. coli isolated from iranian community and clinical settings

BackgroundExtended-spectrum beta-lactamase-producing enterobacteria (ESBL-PE) in carriers have become a global health problem. Using molecular typing techniques, including PFGE, could be useful to determine the source of bacterial dissemination. The current study aimed to investigate the intestinal carriage of ESBL-producing E. coli (ESBL-EC) and clonal relatedness among ESBL-EC isolated from hospitalized and outpatient fecal carriers in Iran.MethodsA total of 120 rectal swabs were collected; 50.8% (61/120) from intensive care unit (ICU) inpatients and 49.2% (59/120) from outpatients. MacConkey agar enriched with cefotaxime was used to screen the ESBL-EC. PCR assays were performed to detect ESBL and carbapenemase genes. Pulse-fields gel electrophoresis (PFGE) was performed to assess clonal relatedness.ResultsTotally, 60.0% (72/120) were carrier for ESBL-EC. The rates of resistance against ceftazidime and cefepime were 90.2% (65/72) and 93.0% (67/72), respectively. The rates of blaCTX-M-15, blaTEM, blaSHV, blaNDM-1, blaOXA-48 and blaIMP was 90.2% (65/72), 50.0% (36/72), 5.5% (4/72), 4.1% (3/72), 4.1% (3/72) and 1.3% (1/72), respectively. Based on a cut-off 80%, 69 ESBL-EC isolates could be categorized in 10 mini-cluster and 47 isolates were considered as singletons.DiscussionHigh heterogeneity among isolates from ESBL-EC suggests that this bacterium probably has a different source of dissemination. Screening of carriers in hospitals and communities could help the infection control program in public health.

Prevalence and Phylodiversity of ESBL-Producing Coliforms Isolated from Ruminant Mastitis in Nigeria

Abstract The public health threat posed by Extended-spectrum beta-lactamase producing E. coli (ESBL-EC) in food animal production systems has attracted global attention. Data on the prevalence, diversity and genetic characteristics of ESBL-producing coliforms are key to advocacy on promoting responsible antimicrobial stewardship and proper planning of control strategies. The coliforms were isolated from 1052 milk samples of 160 cows, 103 ewes and 103 does with mastitis in Plateau State, Nigeria and analysed for ESBL production by phenotypic, biochemical, antimicrobial sensitivity and genetic characterization. The percentage of occurrence of clinical mastitis in cows, ewes, and does were 0.2 %, 0 %, 1.5 % respectively, while the percentage occur-rence of subclinical mastitis in ruminants were 18.1 %, 28.2 % and 38.3 % respectively. From the 677 isolates, 31.3 % (n = 212) were ESBL producing coliforms, with a prevalence of 48.6 %, 18.4 %, 12.7 %, 8.9 %, 5.7 %, 3.8 % and 1.9 % for E. coli, K. pneumoniae, C. freundii, K. aerogenes, S. marcescens, K. oxytoca and E. cloacae, respectively. The genetic characterization revealed a higher prevalence of bla CTX-M than bla TEM in the samples analysed (24.39 % vs. 12.19 %). High pairwise identity was observed among the bla CTX-M and bla TEM gene sequences obtained in this study, but they displayed high phylodiversity with sequences from ruminants and humans from other climes. The bla SHV gene was not detected. Multidrug resistances especially to the commonly used antimicrobials; ofloxacin, gentamycin and streptomycin in veterinary practice in Nigeria were observed. This has public health implications considering the fact that consumption of raw unpasteurized milk is a common practice in some cultures in Nigeria. Such practise will facilitate the transfer of multidrug resistant coliforms to humans resulting in the complications of treatment outcomes. To the best of our knowledge this is the first genetic characterization of ESBL-producing agents from ruminant mastitis in Nigeria.

High Prevalence and Diversity Characteristics of blaNDM, mcr, and blaESBLs Harboring Multidrug-Resistant Escherichia coli From Chicken, Pig, and Cattle in China.

The objective of this study was to understand the diversity characteristics of ESBL-producing Escherichia coli (ESBL-EC) in chicken, pig, and cattle. A high prevalence of ESBL-EC (260/344) was observed in all food animals with prevalence rates of 78.6% (110/140) for chicken, 70.7% (58/82) for cattle, and 75.4% (92/122) for swine. However, the resistance rates presented significant differences in different animal origin ESBL-EC, where resistance to CTX, GEN, IMP, NEO, and OFL was the highest in chicken ESBL-EC, then in cattle, and the lowest in swine. Seriously, most ESBL-EC harbor multidrug resistance to antibiotics (MDR, ≥3 antibiotic categories), and the MDR rates of ESBL-EC were the highest in chicken (98.18%), followed by swine (93.48%), and the lowest in cow (58.62%), while the same trend also was observed in MDR of ≥5 antibiotic categories. This high prevalence and resistance can be partly interpreted by the high carriage rates of the β-lactamases CTX-M (n = 89), OXA (n = 59), SHV (n = 7), and TEM (n = 259). A significant difference of β-lactamase genes also presented in different animal species isolates, where the chicken origin ESBL-EC possessed higher carriage rates of almost all genes tested than cattle and swine. Notably, eight chicken origin ESBL-EC carried transferable plasmid-mediated bla NDM-1 or bla NDM-5, especially, of which four ESBL-EC also contained the colistin resistance gene mcr-1, as confirmed by genomic analysis. More interestingly, two deletion events with a 500-bp deletion in ΔISAba125 and a 180-bp deletion in dsbC were observed in three bla NDM-5 IncX3 plasmids, which, as far as we know, is the first discovery. This showed the instability and horizontal transfer of bla NDM genetic context, suggesting that bla NDM is evolving to “pack light” to facilitate rapid and stable horizontal transfer. Sequence types (STs) and PFGE showed diversity patterns. The most prevalent STs were ST48 (n = 5), ST189 (n = 5), ST206 (n = 4), ST6396 (n = 3), ST10 (n = 3), and ST155 (n = 3), where ST48 ESBL-EC originated from three food animal species. The STs of all bla NDM-positive ESBL-EC were attributed to three STs, namely, ST6396 (n = 2), ST206 (n = 2), and ST189 (n = 4), where ST189 was also the unique type for four mcr-1-carrying ESBL-EC. In conclusion, we suggest that the three animal species ESBL-EC show similar high prevalence, diversity in isolate lineages, and significant discrepancies in antibiotic resistance and resistance genes. This suggests that monitoring and anti-infection of different food animal origin ESBL-EC need different designs, which deserves more attention and further surveillance.

Chromosomal integration of bla CTX-M genes in diverse Escherichia coli isolates recovered from river water in Japan.

Occurrence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBLEC) in environmental waters is of great concern. However, unlike clinical ESBLEC, their genetic characteristics, in particular the genetic contexts of ESBL genes, are not well understood. In this study, we sequenced and analyzed the genomes of CTX-M-producing E. coli isolates recovered from river water to fully characterize the genetic contexts of bla CTX-M genes. Among the 14 isolates with completed genomes, bla CTX-M genes were detected on the chromosome in nine isolates. All but one chromosomal bla CTX-M genes were associated with ISEcp1 and were carried on different transposition units ranging in size from 2,855 bp to 11,093 bp; the exception, bla CTX-M-2, was associated with ISCR1. The remaining five isolates carried bla CTX-M genes on epidemic IncI1 plasmids of different sequence types (STs) (ST3, ST16, ST113, and ST167) (n=4) or on an IncB/O/K/Z plasmid (n=1). This study revealed that environmental E. coli carry bla CTX-M genes in diverse genetic contexts. Apparent high prevalence of chromosomal bla CTX-M potentially indicates that some E. coli can stably maintain bla CTX-M genes in environmental waters, though further studies are needed to confirm this.

Novel Indole Alkaloids from Rauvolfia Yunnanensis, Inhibiting Esbl Producing Escherichia Coli by Targeting Cell Membrane Integrity

Novel Indole Alkaloids from Rauvolfia Yunnanensis, Inhibiting Esbl Producing Escherichia Coli by Targeting Cell Membrane Integrity

Antibacterial Activity of Padikara Parpam against ESBL Producing Escherichia coli and Klebsiella pneumoniae

Aims: To evaluate the antibacterial activity of Padikara Parpam against Extended-Spectrum Beta-Lactamase (ESBL) producing Escherichia Coli and Klebsiella Pneumoniae using agar well diffusion method. To identify ESBL producing bacteria by phenotypic confirmatory test using disk diffusion method.
 Study Design: Analysis of Antibacterial activity of Padikara Parpam using agar well diffusion method.
 Place and Duration of Study: Central Research Laboratory, Meenakshi Academy of higher Education and Research, Chennai, between June 2021 and November 2021.
 Methodology: Clinical isolates of ESBL were isolated by subculture into MacConkey agar and was identified by phenotypic confirmatory test. Padikara parpam's antibacterial activity was evaluated using the Agar well diffusion method at different concentrations of 0.5 %, 1 %, 1.5 %, and 2 % drugs. 30 µg Cefotaxime and 30 µg amoxicillin-clavulanic acid disk were used as controls to standardize the antibacterial activity test and to identify the ESBL by phenotypic confirmatory test.
 Results: In this study, Padikara parpam at various doses of 0.5 %, 1 %, 1.5 %, and 2 %, revealed significant antibacterial efficacy against ESBL producing bacteria. Padikara parpam was more active against ESBL Escherichia coli than ESBL Klebsiella pneumoniae. As a result, it may be recommended as an antibacterial agent against ESBL.
 Conclusion: Our findings suggest that Siddha Herbo mineral formulations of padikara parpam hold phenomenal antimicrobial activity against ESBL producing bacteria. Based on our findings, the drug may be prescribed successfully for urinary tract infections, which is caused by ESBL producing bacteria.

ESBL Producing Escherichia coli in Faecal Sludge Treatment Plants: An Invisible Threat to Public Health in Rohingya Camps, Cox's Bazar, Bangladesh.

Introduction: Human faecal sludge contains diverse harmful microorganisms, making it hazardous to the environment and public health if it is discharged untreated. Faecal sludge is one of the major sources of E. coli that can produce extended-spectrum β-lactamases (ESBLs).Objective: This study aimed to investigate the prevalence and molecular characterization of ESBL-producing E. coli in faecal sludge samples collected from faecal sludge treatment plants (FSTPs) in Rohingya camps, Bangladesh.Methods: ESBL producing E. coli were screened by cultural as well as molecular methods and further characterized for their major ESBL genes, plasmid profiles, pathotypes, antibiotic resistance patterns, conjugation ability, and genetic similarity.Results: Of 296 isolates, 180 were phenotypically positive for ESBL. All the isolates, except one, contained at least one ESBL gene that was tested (blaCTX−M−1, blaCTX−M−2, blaCTX−M−8, blaCTX−M−9, blaCTX−M−15, blaCTX−M−25, blaTEM, and blaSHV). From plasmid profiling, it was observed that plasmids of 1–211 MDa were found in 84% (151/180) of the isolates. Besides, 13% (24/180) of the isolates possessed diarrhoeagenic virulence genes. From the remaining isolates, around 51% (79/156) harbored at least one virulence gene that is associated with the extraintestinal pathogenicity of E. coli. Moreover, 4% (3/156) of the isolates were detected to be potential extraintestinal pathogenic E. coli (ExPEC) strains. Additionally, all the diarrhoeagenic and ExPEC strains showed resistance to three or more antibiotic groups which indicate their multidrug-resistant potential. ERIC-PCR differentiated these pathogenic isolates into seven clusters. In addition to this, 16 out of 35 tested isolates transferred plasmids of 32–112 MDa to E. coli J53 recipient strain.Conclusion: The present study implies that the faecal sludge samples examined here could be a potential origin for spreading MDR pathogenic ESBL-producing E. coli. The exposure of Rohingya individuals, living in overcrowded camps, to these organisms poses a severe threat to their health.

Carriage of ESBL-producing Enterobacterales in wastewater treatment plant workers and surrounding residents - the AWARE Study.

To investigate whether wastewater treatment plant (WWTP) workers and residents living in close proximity to a WWTP have elevated carriage rates of ESBL-producing Enterobacterales, as compared to the general population. From 2018 to 2020, we carried out a cross-sectional study in Germany, the Netherlands, and Romania among WWTP workers (N = 344), nearby residents (living ≤ 300 m away from WWTPs; N = 431) and distant residents (living ≥ 1000 m away = reference group; N = 1165). We collected information on potential confounders via questionnaire. Culture of participants’ stool samples was performed with ChromID®-ESBL agar plates and species identification with MALDI-TOF–MS. We used logistic regression to estimate the odds ratio (OR) for carrying ESBL-producing E. coli (ESBL-EC). Sensitivity analyses included stratification by country and interaction models using country as secondary exposure. Prevalence of ESBL-EC was 11% (workers), 29% (nearby residents), and 7% (distant residents), and higher in Romania (28%) than in Germany (7%) and the Netherlands (6%). Models stratified by country showed that within the Romanian population, WWTP workers are about twice as likely (aOR = 2.34, 95% CI: 1.22–4.50) and nearby residents about three times as likely (aOR = 3.17, 95% CI: 1.80–5.59) to be ESBL-EC carriers, when compared with distant residents. In stratified analyses by country, we found an increased risk for carriage of ESBL-EC in Romanian workers and nearby residents. This effect was higher for nearby residents than for workers, which suggests that, for nearby residents, factors other than the local WWTP could contribute to the increased carriage.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10096-021-04387-z.

Cefmetazole as an Alternative to Carbapenems Against Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Infections Based on In Vitro and In Vivo Pharmacokinetics/Pharmacodynamics Experiments.

Cefmetazole (CMZ) has received attention as a pharmaceutical intervention for extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) infections. This study aimed to investigate the pharmacokinetics/pharmacodynamics (PK/PD) characteristics of CMZ against ESBL-EC. The susceptibility and time-killing activity of CMZ against clinically isolated ESBL-EC (EC9 and EC19) were determined in vitro. The optimal PK/PD index and its target value were calculated based on the results of a PK study in healthy mice and PD study in neutropenic murine thigh infection model mice. The minimum inhibitory concentrations (MICs) of CMZ against EC9 and EC19 were 2.0 and 1.0µg/mL, respectively. Time-kill studies showed that colony-forming units decreased in a time-dependent manner at CMZ concentrations in the range of 4-64 × MIC. In in vivo PK/PD studies, the antibacterial effect of CMZ showed the better correlation with the time that the free drug concentration remaining above the MIC (fT>MIC), with the target values for a static effect and 1 log10 kill reduction calculated as 57.6% and 69.6%, respectively. CMZ possesses time-dependent bactericidal activities against ESBL-EC and is required to achieve "fT>MIC" ≥ 69.6% for the treatment of ESBL-EC infections.

Epidemiology of ESBL-producing Escherichia coli from repeated prevalence studies over 11\xa0years in a long-term-care facility

BackgroundEscherichia coli sequence type (ST) 131 H30 is an emerging multidrug resistant subclone, known to spread and cause outbreaks in long-term care facilities (LTCFs).Objectives and methodsFrom 2010 through 2020, we performed 11 yearly surveillance studies for determining the prevalence of digestive carriage of ESBL-producing E. coli (ESBL-EC) among residents in a university-affiliated LCTF. Sequencing and genotyping of selected isolates were performed to characterize temporal trends in the prevalence and epidemic potential of ESBL-EC subclones, and for evaluating a potential rebound effect following discontinuation of contact precautions for ESBL-EC carriers in January 2019.ResultsThis study included 2′403 LTCF residents, with 252 (10.5%) positive for ESBL-EC. Among the 236 ESBL-EC isolates available for typing, 58.0% belonged to the ST131 lineage, including 94/137 (68.6%) ST131 H30 isolates. An increasing yearly prevalence was observed for ESBL-EC (from 4.6 to 9.4%; p = 0.11), but not for the ST131 H30 subclone, which peaked in 2015 and declined thereafter. Multiple previously unnoticed ESBL-EC outbreaks occurred in the LTCF. Since 2018, we noted the clonal expansion of a rare ST131 H89 subclone (O16:H5) harboring CTX-M-14 and CTX-M-24. No rebound effect was observed in ESBL-EC prevalence nor in the different subclones following discontinuation of contact precautions for ESBL-EC carriers since 2019.ConclusionClonal fluctuation was observed for ST131 H30 ESBL-EC with a current decline in prevalence. Surveillance should include the evolution of ST131 non-H30 subclones, which may spread in LTCFs. Our findings suggest that discontinuation of contact precautions for ESBL-EC carriers in LTCFs may be safely implemented, in support of European recommendations to limit ESBL-producing Enterobacteriaceae control measures in endemic settings to non-E. coli.

Genetic evaluation of ESBL-producing Escherichia coli urinary isolates in Otago, New Zealand.

ObjectivesThe incidence of infections with ESBL-producing Escherichia coli (ESBL-Ec) in New Zealand is increasing. ESBL-Ec most commonly cause urinary tract infections and are seen in both community and hospitalized patients. The reason for the increasing incidence of ESBL-Ec infections is unknown.MethodsIn this study, 65 urinary ESBL-Ec isolates from the Otago region in 2015 were fully genetically characterized to understand the mechanisms of transmission. The ESBL gene, E. coli STs, plasmid types and genetic context (e.g. insertion sequences) of ESBL genes were determined by a combination of whole genome and plasmid sequencing. The phylogenetic relationships of the isolates were compared with ESBL-Ec isolates sequenced as part of the 2016 nationwide survey.ResultsSignificant diversity of E. coli strains, plasmids, and the genetic context of ESBL genes was seen. However, there was evidence of common mobile genetic elements in unrelated ESBL-Ec.ConclusionsMultiple introductions of ESBL resistance genes or resistant bacterial strains with limited horizontal transmission of mobile genetic elements accounts for the increased incidence of ESBL-Ec in this low prevalence area. Future studies should investigate modes of transmission of ESBL-Ec in the Otago region.

Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli survey in wild seabirds at a pristine atoll in the southern Atlantic Ocean, Brazil: First report of the O25b-ST131 clone harboring blaCTX-M-8

Antimicrobial resistance is among the most serious public health threats of the 21st century, with great impact in terms of One Health. Among antimicrobial resistant bacteria (ARB), extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) represent major challenges to human healthcare. Wild birds have been commonly used as environmental bioindicators of ESBL-EC. Remote locations represent a unique opportunity to evaluate the occurrence, dissemination and epidemiology of ARB in the environment. Herein we surveyed ESBL-EC in 204 cloacal swabs from six nonsynanthropic seabird species at the pristine Rocas Atoll, Brazil. We identified ESBL-EC isolates in 2.4% (5/204) of the tested seabirds, all in magnificent frigatebirds (Fregata magnificens). We isolated strains of O25b-ST131-fimH22 harboring gene blaCTX-M-8 (3 clones), ST117 harboring gene blaSHV-12, and a novel ST11350 (clonal complex 349) harboring genes blaCTX-M-55 and fosA3. All the isolates presented Extraintestinal pathogenic E. coli (ExPEC) virulence profiles. We suggest that magnificent frigatebirds may act as “flying bridges”, transporting ESBL-EC and ARGs from an anthropogenically-impacted archipelago geographically close to our pristine and remote study site. The characteristics of our isolates suggest zoonotic potential and, despite the apparent good health of all the evaluated birds, may represent a hypothetical potential threat to the avian population using the atoll. To our knowledge, this is the first description of: (1) the pandemic and public health relevant ST131-O25b harboring blaCTX-M-8 worldwide; (2) ST131-fimH22 in wild birds; and (3); fosA3 in wildlife. Our findings expand the current epidemiological knowledge regarding host and geographical distribution of ESBL-EC and ARGs in wild birds, and emphasize the disseminating characteristics and adaptability of ST131 and ST117 strains within the human-animal-interface. Herein we discuss the involvement of nonsynanthropic wild birds in the epidemiology of antimicrobial resistance and their potential as sentinels of ESBL E. coli in insular environments.

Genomic Characterization of ESBL- and Carbapenemase-Positive Enterobacteriaceae Co-harboring mcr-9 in Japan.

Worldwide spread of Enterobacteriaceae resistant to colistin, a polypeptide antibacterial drug for last-resort treatment of carbapenemase-producing Enterobacteriaceae (CPE) infections, is concerning. This study aimed to elucidate colistin MICs and molecular characteristics of mcr-1 to mcr-9 of ESBL-producing Escherichia coli (ESBL-Ec) and CPE in Japan and clarify the genomic structure of strains harboring mcr genes (especially mcr-9). This study included 168 ESBL-Ec and 126 CPE strains isolated at Japanese medical facilities. Colistin susceptibility testing and multiplex PCR targeting mcr-1 to mcr-9 were performed for all strains with S1-nuclease pulsed-field gel electrophoresis, Southern blot hybridization, and whole-genome sequencing (WGS) with hybrid assembly performed for mcr gene-carrying strains. Two CPE strains showed a MIC ≥ 4 μg/ml in colistin susceptibility testing, with no known resistance mechanism detected. However, PCR conducted on all target strains detected three mcr-9-carrying strains showing colistin susceptibility. The blaCTX–M–62-positive E. coli THUN648 strain simultaneously carried blaCTX–M–62 and mcr-9 on a 275-kbp plasmid. Besides, blaIMP–6 + blaCTX–M–2-positive Klebsiella pneumoniae THUN262 and blaGES–24-positive Enterobacter kobei THUN627 had mcr-9 encoded on the chromosome. Only THUN627 encoded qseB/C, which is suggested to be a regulatory gene for mcr-9, downstream of mcr-9. However, this strain showed no increased expression of these genes in mRNA quantitative analysis under colistin exposure. Colistin MICs of ESBL-Ec and CPE in Japan were all below 2 μg/ml, which is below the epidemiological cutoff (ECOFF) value (https://eucast.org/) or clinical breakpoint (CB) (CLSI M100-S30) reported for colistin, indicating neither “microbiological” nor “clinical” resistance. Several colistin-susceptible Enterobacteriaceae carrying silent mcr-9 encoded on plasmids and chromosomes have already spread worldwide along with other antimicrobial resistance genes. However, the mechanism of colistin resistance by mcr-9 remains unclear.

Retrospective evaluation of appropriate dosing of cefmetazole for invasive urinary tract infection due to extended-spectrum β-lactamase-producing Escherichia coli

IntroductionThe frequency of urinary tract infections (UTIs) caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacterales is steadily increasing worldwide. Therefore, we aimed to evaluate the efficacy and appropriate dosing of cefmetazole (CMZ) in invasive urinary tract infection (iUTI) caused by ESBL-producing Escherichia coli (ESBLEC). MethodsPatients who developed ESBLEC iUTI and received CMZ between January 2007 and December 2018 were identified, and their medical records were reviewed. The time above minimum inhibitory concentration (MIC) (TAM) was calculated using the MIC value obtained from each patient and its simulated CMZ concentration. ResultsThirty-nine patients were included in the study. The median TAM was 92.6% (interquartile range [IQR], 67.6–100). CMZ was clinically efficacious in 38 (97.4%) patients overall and in 11 out of 12 (91.7%) patients with normal renal function who received CMZ at 1 g every 8 h. ConclusionsIn normal renal function, 1 g CMZ infused for over 1 h every 8 h is an efficacious treatment for iUTI caused by ESBLEC with MIC =< 4 mg/L.

Populations of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae are different in human-polluted environment and food items: a multicentre European study

ObjectivesTo assess the extent to which food items are a source of extended-spectrum β-lactamase (ESBL) -producing Escherichia coli (ESBL-Ec) and ESBL-producing Klebsiella pneumoniae (ESBL-Kp) for humans in five European cities. MethodsWe sampled 122 human polluted (hp)-environments (sewers and polluted rivers, as a proxy of human contamination) and 714 food items in Besançon (France), Geneva (Switzerland), Sevilla (Spain), Tübingen (Germany) and Utrecht (The Netherlands). A total of 254 ESBL-Ec and 39 ESBL-Kp isolates were cultured. All genomes were fully sequenced to compare their sequence types (ST) and core genomes, along with the distribution of blaESBL genes and their genetic supports (i.e. chromosome or plasmid). ResultsSequence data revealed that ESBL-Ec and ESBL-Kp isolates from hp-environments were genetically different from those contaminating food items. ESBL-Ec ST131 was widespread in the hp-environment (21.5% of the isolates) but absent from the food items tested. ESBL-Ec ST10 was in similar proportions in hp-environments and food items (15 and 10 isolates, respectively) but mostly carried reservoir-specific blaESBL. blaCTX-M-1 and blaSHV-12 predominated in food-related E. coli isolates (32% and 34% of the isolates, respectively), whereas blaCTX-M-15 and blaCTX-M-27 predominated in isolates from hp-environments (52% and 15% of the isolates, respectively). ConclusionsWe found a very limited connection between ESBL-Ec and ESBL-Kp populations retrieved in food items and from hp-environments and blaESBL. This suggests that human-to-human contamination, rather than the food chain, is possibly the most frequent route of ESBL-Ec and ESBL-Kp transmission in high-income countries.

Extended Spectrum Beta-Lactamase Escherichia coli in River Waters Collected from Two Cities in Ghana, 2018-2020.

Infections by Extended-Spectrum Beta-Lactamase producing Escherichia coli (ESBL-Ec) are on the increase in Ghana, but the level of environmental contamination with this organism, which may contribute to growing Antimicrobial Resistance (AMR), is unknown. Using the WHO OneHealth Tricycle Protocol, we investigated the contamination of E. coli (Ec) and ESBL-Ec in two rivers in Ghana (Odaw in Accra and Okurudu in Kasoa) that receive effluents from human and animal wastewater hotspots over a 12-month period. Concentrations of Ec, ESBL-Ec and percent ESBL-Ec/Ec were determined per 100 mL sample. Of 96 samples, 94 (98%) were positive for ESBL-Ec. concentrations per 100 mL (MCs100) of ESBL-Ec and %ESBL-Ec from both rivers were 4.2 × 104 (IQR, 3.1 × 103–2.3 × 105) and 2.79 (IQR, 0.96–6.03), respectively. MCs100 were significantly lower in upstream waters: 1.8 × 104 (IQR, 9.0 × 103–3.9 × 104) as compared to downstream waters: 1.9 × 106 (IQR, 3.7 × 105–5.4 × 106). Both human and animal wastewater effluents contributed to the increased contamination downstream. This study revealed high levels of ESBL-Ec in rivers flowing through two cities in Ghana. There is a need to manage the sources of contamination as they may contribute to the acquisition and spread of ESBL-Ec in humans and animals, thereby contributing to AMR.

Etiology and prevalence of ESBLs in adult community-onset urinary tract infections in East China: A prospective multicenter study

ObjectivesCommunity onset urinary tract infections (COUTIs) drew attention recently owing to their increased prevalence and associations with resistant pathogens. The study is aimed at investigating the etiology of COUTIs as well as prevalence and the related risk factors of extended-spectrum β-lactamase (ESBL) in COUTIs in China. MethodsThe prospective study was performed in nineteen hospitals during November 1, 2017 and August 31, 2019. Non-duplicated isolates from COUTIs were included. The ESBL phenotypic confirmation test was performed and whole genomes were sequenced for all the ESBL-positive bacteria for further analysis. The risk factors for ESBL-producing bacterial infections were analyzed using binary logistic regression. ResultsA total of 1760 COUTI cases were included in this study. Escherichia coli (1332, 75.7%), Klebsiella pneumoniae (110, 6.3%) and Enterococcus faecalis (52, 3.0%) were the top three common pathogens of COUTIs in China. The overall positive rate of ESBLs in Enterobacterales was 37.2% (562/1512). The age (OR=1.007, P = 0.041), solid malignant tumor (OR=1.668, P = 0.016), prostate diseases (OR=2.035, P = 0.010), history of lithotripsy for urinary calculi (OR=2.009, P = 0.030), history of urological surgery (OR=1.869, P = 0.009) and cephalosporin use within 3 months (OR=1.503, P = 0.025) were independent risk factors for ESBL-producing organisms causing COUTIs. The predominant ESBL types were CTX-Ms, among which CTX-M-14, CTX-M-55 and CTX-M-27 were the most common subtypes. ST131 and ST1193 were the predominant sequence types of ESBL-producing E. coli (ESBL-EC). Most of the tested antimicrobial agents showed significantly higher non-susceptible rates in the ESBL positive group as compared with ESBL-negative group (P < 0.05). ConclusionsEnterobacterales, especially E. coli, is the most common pathogen in COUTIs in China and ESBL-producers are highly prevalent. Thus, early prediction depending on risk factors seems to be crucial to determine the appropriate empirical therapy for infections caused by ESBL-producing pathogens.

Extended-spectrum beta-lactamase-producing strains among diarrhoeagenic Escherichia coli-prospective traveller study with literature review.

BackgroundAntibiotics are no longer the primary approach for treating all travellers’ diarrhoea (TD): most cases resolve without antibiotics and using them predisposes to colonization by multidrug-resistant bacteria. Data are accumulating on increasing resistance among TD pathogens, yet research into the most common agents, diarrhoeagenic Escherichia coli (DEC), remains limited.MethodsA total of 413 travellers to the (sub)tropics were analyzed for travel-acquired diarrhoeal pathogens and ESBL-PE. To identify ESBL-producing DEC, ESBL-producing E. coli (ESBL-EC) isolates were subjected to multiplex qPCR for various DEC pathotypes: enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enteroinvasive (EIEC) and enterohaemorrhagic (EHEC) E. coli.For a literature review, we screened studies among travellers and locals in low- and middle-income countries (LMICs) on the frequency of ESBL-producing DEC, and among travellers, also DEC with resistance to ciprofloxacin, azithromycin, and rifamycin derivatives.ResultsOur rate of ESBL-EC among all DEC findings was 2.7% (13/475); among EAEC 5.7% (10/175), EPEC 1.1% (2/180), ETEC 1.3% (1/80) and EHEC (0/35) or EIEC 0% (0/5). The literature search yielded three studies reporting ESBL-EC frequency and thirteen exploring resistance to TD antibiotics among travel-acquired DEC. For EAEC and ETEC, the ESBL-EC rates were 10–13% and 14–15%, resistance to fluoroquinolones 0–42% and 0–40%, azithromycin 0–29% and 0–61%, and rifaximin 0% and 0–20%. The highest rates were from the most recent collections. Proportions of ESBL-producing DEC also appear to be increasing among locals in LMICs and even carbapenemase-producing DEC were reported.ConclusionESBL producers are no longer rare among DEC, and the overall resistance to various antibiotics is increasing. The data predict decreasing efficacy of antibiotic treatment, threatening its benefits, for disadvantages still prevail when efficacy is lost.

Prevalence of mobile colistin resistance (mcr) genes in extended-spectrum β-lactamase-producing Escherichia coli isolated from retail raw foods in Nha Trang, Vietnam

The aim of the study was to assess the presence of genes in ESBL-producing E. coli (ESBL-Ec) isolated from retail raw food in Nha Trang, Vietnam. A total of 452 food samples comprising chicken (n = 116), pork (n = 112), fish (n = 112) and shrimp (n = 112) collected between 2015 and 2017 were examined for the prevalence of ESBL-Ec. ESBL-Ec were detected in 46.0% (208/452) of retail food samples, particularly in 66.4% (77/116), 55.4% (62/112), 42.0% (47/112) 19.6% (22/112) of chicken, pork, fish and shrimp, respectively. Sixty-five out of the 208 (31.3%) ESBL-Ec isolates were positive for mcr genes including mcr-1, mcr-3 and both mcr-1 and mcr-3 genes in 56/208 (26.9%), 1/208 (0.5%) and 8/208 (3.9%) isolates, respectively. Particularly, there was higher prevalence of mcr-1 in ESBL-Ec isolates from chicken (53.2%, 41/77) in comparison to shrimp (22.7%, 5/22), pork (11.3%, 7/62) and fish (6.4%, 3/47). mcr-3 gene was detected in co-existence with mcr-1 in ESBL-Ec isolates from shrimp (9.1%, 2/22), pork (8.1%, 5/62) and fish (2.1%, 1/47) but not chicken. The 65 mcr-positive ESBL-Ec (mcr-ESBL-Ec) were colistin-resistant with the MICs of 4–8 μg/mL. All mcr-3 gene-positive isolates belonged to group A, whereas phylogenetic group distribution of isolates harboring only mcr-1 was B1 (44.6%), A (28.6%) and D (26.8%). PFGE analysis showed diverse genotypes, although some isolates demonstrated nearly clonal relationships. S1-PFGE and Southern hybridization illustrated that the mcr-1 and mcr-3 genes were located either on chromosomes or on plasmids. However, the types of mcr genes were harbored on different plasmids with varied sizes of 30–390 kb. Besides, the ESBL genes of CTX-M-1 or CTX-M-9 were also detected to be located on plasmids. Noteworthy, co-location of CTX-M-1 with mcr-1 or mcr-3 genes on the same plasmid was identified. The conjugation experiment indicated that the mcr-1 or mcr-3 was horizontally transferable. All mcr-ESBL-Ec isolates were multidrug resistance (resistance to ≥3 antimicrobial classes). Moreover, β-Lactamase-encoding genes of the CTX-M-1 (78.5%), CTX-M-9 (21.5%), TEM (61.5%) groups were found in mcr-ESBL-Ec. The astA gene was detected in 27 (41.5%) mcr-ESBL-Ec isolates demonstrating their potential virulence. In conclusion, mcr-1 and mcr-3 genes existed individually or concurrently in ESBL-Ec isolates recovered from retail raw food in Nha Trang city, which might further complicate the antimicrobial-resistant situation in Vietnam, and is a possible health risk for human.

Human Colonization with Extended-Spectrum Beta-Lactamase-Producing E. coli in Relation to Animal and Environmental Exposures in Bangladesh: An Observational One Health Study.

Background:Human exposure to intensively farmed livestock is a potential risk for transmission of antibiotic-resistant bacteria (ARB) but few studies have assessed the relative role of animal vs. environmental sources of ARB in low-resource community settings.Objectives:We conducted an observational study to compare ARB colonization and antibiotic-resistant gene prevalence and abundance in humans with high or low exposure to poultry in rural households, commercial poultry farms, and urban markets in Bangladesh.Methods:Extended-spectrum (ESBL)-producing and carbapenem-resistant E. coli were quantified in feces from adults with high or low poultry exposure (, respectively), poultry (), drinking water (), and wastewater () from 40 rural households, 40 poultry farms, and 40 urban markets.Results:ESBL-producing E. coli (ESBL-EC) prevalence was 67.5% (95% CI: 61.0, 74.0) in samples from adults, 68.0% (95% CI: 61.5, 74.5) in samples from poultry, and 92.5% (95% CI: 87.7, 97.3) in wastewater samples. Carbapenem-resistant E. coli prevalence was high in market wastewaters [30% (95% CI: 15.0, 45.0)] but low in humans (1%) and poultry (1%). Human, poultry, and wastewater isolates shared common resistance genes: , qnr, and . Human colonization was not significantly associated with exposure to poultry or setting (rural, farm, or market). Ninety-five percent of commercial poultry farms routinely administered antibiotics. Susceptibility tests were significantly different in household vs. farm and market poultry isolates for four of seven antibiotic classes. In human isolates, there were no differences except aminoglycoside resistance (16.4% high vs. 4.4% low exposure, ). Urban market wastewaters and poultry samples had significantly higher concentrations of ESBL-EC () and () compared with samples from farms and rural households.Discussion:ESBL-EC colonization was high in humans but not significantly associated with exposure to poultry. Bidirectional transmission of antibiotic resistance is likely between humans, poultry, and the environment in these community settings, underlining the importance of One Health mitigation strategies. https://doi.org/10.1289/EHP7670