An overview of carbapenem-resistant organisms from food-producing animals, seafood, aquaculture, companion animals, and wildlife

NDM-5-plasmid diversity in multiple international high-risk Escherichia coli clones associated with canine and feline extraintestinal infections

NDM-5-producing Escherichia coli are the predominant carbapenemase producers of medical and public health importance. The global spread of blaNDM-5-containing plasmids in high-risk E. coli clones has been primarily documented in humans and increasingly reported in animals and the environment. Here, we used whole-genome sequence analysis to describe the genetic diversity of 16 high-risk NDM-5-producing E. coli strains, with a variety of NDM-5 plasmids, isolated from dogs and cats with extraintestinal infections in Thailand between 2017 and 2021. The strains belonged to sequence type (ST) 410 (n = 8), ST354 (n = 3), ST648 (n = 2), ST361 (n = 1), ST617 (n = 1), and ST641 (n = 1). The ST641 strain carried blaNDM-5 on an IncX3 plasmid, while blaNDM-5 was localized on single-replicon or multi-replicon IncF plasmids in other STs. Non-conjugative F1:A1:B49 NDM-5 plasmids were limited to ST410 strains. They contained blaNDM-5 associated with the IS26-bounded complex class 1 integron (Int1) with dfrA17-aadA5-qacEΔ1-sul1 cassette array that shared similarities to nearly identical structures with the plasmids of ST410 strains from humans in Thailand and Myanmar. Conjugative IncFII (F2:A-:B-) NDM-5 plasmids containing Int1 with dfrA12-aadA2-qacEΔ1-sul1 cassette array were present in ST354 and ST648, and heterogeneous plasmid STs of conjugative multi-replicon IncF NDM-5 plasmids were found in ST361, ST410, ST617, and ST648. The blaNDM-5 elements mobilized by IS26 were shared among various IncF plasmids in high-risk E. coli clones but were conserved within the endemic E. coli ST410, representing the predominant lineage in Southeast Asian countries. Dogs and cats can develop infections with NDM-5-producing E. coli, posing the risk of further disseminating carbapenemase in veterinary settings and the community. This emphasizes the need to implement infection control and antimicrobial resistance surveillance programs in veterinary settings.

A systematic review and meta-analysis of carbapenem-resistant Enterobacteriaceae in West Africa

BACKGROUND

In Africa, the problem of carbapenem-resistant Enterobacteriaceae (CRE) is aggravated by many factors. This systematic review attempted to describe the current status of the molecular epidemiology of carbapenem resistance in West Africa (WA).

METHODS

Articles published from 16 West African countries on the molecular epidemiology of carbapenem resistance were reviewed. An extensive literature search was carried out in PubMed, Scopus, Web of Science, and African Journals Online (AJOL) using specific keywords. The meta-analysis and forest plots of major pathogens and carbapenem resistance genes were done using the Open Meta-Analyst, Task Order # 2 software. The data were analysed in binary random model effects by the DerSimonian-Laird method at a 95% confidence interval.

RESULTS

Of the 431 articles found in our initial search, 60 (13.92%) were considered suitable for inclusion. Only seven of the 16 West African countries formed part of the analysis, Nigeria (23/60), Ghana (19/60), Burkina Faso (7/60), Senegal (6/60), Benin (2/60), Mali (2/60), and Togo (1/60). Also, 80% (48/60) of the studies used clinical samples, 16.67% (10/60) used environmental samples, and 3.33% (2/60) used animal samples. The average prevalence was highest in Acinetobacter baumannii (18.6%; 95% CI = 14.0-24.6, I2 = 97.9%, p < 0.001), followed by Pseudomonas aeruginosa (6.5%; 95% CI = 3.1-13.4, I2 = 96.52%, p < 0.001), Klebsiella pneumoniae (5.8%; 95% CI = 4.2-7.9, I2 = 98.06%, p < 0.001) and Escherichia coli (4.1%; 95% CI = 2.2-7.7, I2 = 96.68%, p < 0.001). The average prevalence of the blaNDM gene was 10.6% (95% CI = 7.9-14.3, I2 = 98.2%, p < 0.001), followed by 3.9% (95% CI: 1.8-8.3, I2 = 96.73%, p < 0.001) for blaVIM and 3.1% (95% CI: 1.7-5.8, I2 = 91.69%, p < 0.001) for blaOXA-48.

CONCLUSION

In West Africa, K. pneumoniae, E. coli, A. baumannii, and P. aeruginosa are the main CRE with blaNDM, blaVIM, and blaOXA-48 being the predominant carbapenem resistance genes. In view of these results, ongoing CRE surveillance combined with antimicrobial stewardship improved, laboratory detection methods, and adherence to infection control practices will be needed to control the spread of CRE.

Therapeutic Phage Candidates for Targeting Prevalent Sequence Types of Carbapenem-Resistant Escherichia coli

Carbapenem-resistant Escherichia coli (CREC) is a global threat to public health; therefore, alternative treatment options are urgently needed. Bacteriophages have emerged as promising candidates for combating CREC infections. This study aimed to investigate the genetic basis of phage sensitivity in CREC by evaluating carbapenem resistance among multidrug-resistant (MDR) E. coli isolated in Daegu, South Korea and analyzing their sequence types (STs) with phage susceptibility spectra. Among the 60 MDR E. coli isolates, 80.4% were identified as CREC, with 77.0% demonstrating resistance to imipenem and 66.6% to meropenem. Moreover, 70 lytic E. coli bacteriophages were isolated from hospital sewage water and evaluated against those 60 E. coli isolates. The phages exhibited lytic activity of 33%-60%, with average titers ranging from 5.6 × 1012 to 2.4 × 1013 PFU/mL (Plaque-Forming Unit). Furthermore, multilocus sequence typing (MLST) analysis of the bacterial isolates revealed 14 distinct STs, mostly belonging to ST131, ST410, and ST648. Notably, the phage susceptibility spectra of ST73, ST13003, ST648, ST2311, ST167, ST405, ST607, ST7962, and ST131 were significantly different. Thus, the isolated phages can effectively lyse CREC isolates, particularly those with clinically dominant STs. Conversely, ST410 exhibited a 14.2%-87.14% susceptibility spectrum, whereas ST1139, ST1487, ST10, and ST206 did not lyse, suggesting the presence of more resistant STs. Future studies are warranted to identify the reasons behind this resistance and address it. Ultimately, this study will aid in developing focused treatments to address these pressing global health issues.

Awareness on the spread of carbapenem-resistant Enterobacterales in animals as One Health

One Health is a multisectoral cooperative and collaborative approach aimed at achieving integrated health by recognizing the interconnectedness of people, animals, plants, and the environment. In the modern world, the One Health approach is considered an essential perspective for overcoming various emerging diseases, including antimicrobial resistance (AMR). One of the top priority AMR infections is caused by carbapenem-resistant Enterobacterales (CRE), which are bacterial strains not susceptible to carbapenems, the last-resort antibiotics for clinical Gram-negative bacterial infections. Although carbapenems are not allowed to use in animals in the global community, various types of CRE are being reported among animals, including the carbapenemase-producing Enterobacterales (CPE). Therefore, since the dissemination and clinical infection of CPE represent a shared health threat, measures to raise awareness of this issue should be considered from the perspective of the One Health approach.

Extended-spectrum ß-lactamase (ESBL)- and Carbapenemase-producing Enterobacterales Isolated from Fresh Herbs and Salads at Retail Level in Switzerland

Fresh produce is usually consumed raw or minimally processed, making it a potential vehicle for the transmission of antimicrobial-resistant (AMR) microorganisms to humans. The objective of the study was to assess the occurrence of extended-spectrum ß-lactamase (ESBL)- and carbapenemase-producing Enterobacterales (ESBL-E and CPE), respectively, in 118 fresh herbs and 101 bagged salads collected at retail level in Switzerland and to characterize the isolates' phenotypic and genotypic properties using culture-based methods and whole genome sequencing (WGS). Of the fresh herbs, 6/118 contained ESBL-E and 7/118 yielded CPE. Of the salads, 13/101 contained ESBL-E and 1/101 CPE. Antimicrobial susceptibility testing (AST) identified 9/29 isolates as multidrug-resistant (MDR). ESBL-E were Escherichia coli (n = 6), Klebsiella pneumoniae (n = 4) Enterobacter chuandaensis (n = 1), and Kluyvera spp. (n = 1) carrying ß-lactamase (bla) genes belonging to the cefotaximase-München (blaCTX-M)-groups, Proteus spp. (n = 1) containing Hôpital-Universitaire-de-Genève-bla (blahugA), Raoultella ornithinolytica (n = 1) carrying sulfhydryl reagent variable bla (blaSHV), and Serratia fonticola (n = 7) carrying S. fonticula bla (blaFONA) genes. CPE were Enterobacter asburiae (n = 1) E. cloacae (n = 6) and E. vonholyi (n = 1) carrying imipenemase bla (blaIMI) genes. Several K. pneumoniae sequence types (STs) were identified (ST967, ST628, ST219, and ST1823), which have been linked to human disease and nosocomial outbreaks. They carried blaCTX-M-15 on plasmids detected globally in environmental and clinical samples. E. coli (ST10, ST48, ST609, ST2040, ST6215 and ST3580) and enterotoxigenic E. coli (ETEC) ST2040 carrying blaCTX-M-15 were found. E. cloacae (ST820 and ST1516) with blaIMI-1 have been found previously in clinical settings and community outbreaks. The occurrence and consumption of fresh produce containing MDR ESBL-E and CPE pose substantial public health risks and raise significant food safety concerns.

Escherichia coli from six European countries reveals differences in profile and distribution of critical antimicrobial resistance determinants within One Health compartments, 2013 to 2020

BackgroundAntimicrobial resistance (AMR) is a global threat. Monitoring using an integrated One Health approach is essential to detect changes in AMR occurrence.AimWe aimed to detect AMR genes in pathogenic and commensal Escherichia coli collected 2013-2020 within monitoring programmes and research from food animals, food (fresh retail raw meat) and humans in six European countries, to compare vertical and horizontal transmission.MethodsWe whole genome sequenced (WGS) 3,745 E. coli isolates, detected AMR genes using ResFinder and performed phylogenetic analysis to determine isolate relatedness and transmission. A BLASTn-based bioinformatic method compared draft IncI1 genomes to conserved plasmid references from Europe.ResultsResistance genes to medically important antimicrobials (MIA) such as extended-spectrum cephalosporins (ESC) were widespread but predicted resistance to MIAs authorised for human use (carbapenem, tigecycline) was detected only in two human and three cattle isolates. Phylogenetic analysis clustered E. coli according to phylogroups; commensal animal isolates showed greater diversity than those from human patients. Only 18 vertical animal-food and human-animal transmission events of E. coli clones were detected. However, IncI1 plasmids from different sources and/or countries carrying resistance to ESCs were conserved and widely distributed, although these variants were rarely detected in human pathogens.ConclusionUsing WGS we demonstrated AMR is driven vertically and horizontally. Human clinical isolates were more closely related, but their IncI1 plasmids were more diverse, while animal or food isolates were less similar with more conserved IncI1 plasmids. These differences likely arose from variations in selective pressure, influencing AMR evolution and transmission.

Emerging blaNDM-positive Salmonella enterica in Chinese pediatric infections

Non-typhoidal Salmonella (NTS) is a common zoonotic foodborne pathogen, whose rising antimicrobial resistance has been an urgent threat to global public health. Here, we reported two carbapenem-resistant Salmonella enterica (CRSE) strains (NBFE-049 and NBFE-164) carrying the blaNDM genes, which were recovered from two Chinese children, belonged to Salmonella enterica serovar Typhimurium (S. Typhimurium) monophasic variant (S. 1,4,[5],12:i:-) ST34 (a sequence type) and S. Typhimurium ST19, respectively. Genes blaNDM-5 and blaNDM-13 were detected in NBFE-049 and NBFE-164, respectively. The blaNDM-5 in NBFE-049 was located in an IncHI2-type plasmid, named pNBFE-049. In NBFE-164, the blaNDM-13 was located in an IncI1-type plasmid, named pNBFE-164. The plasmid pNBFE-164 successfully transferred its resistance phenotype into the recipient strain Escherichia coli J53 with a high efficiency of 1.1 × 10-2, while no transconjugants were obtained in pNBFE-049 conjugation assays. We further elucidated the genetic relationships of globally occurring New Delhi Metallo-β-lactamase (NDM)-positive strains and locally distributed clinical strains within the same serovar. The closest relative of NBFE-049 was clinical Salmonella strain 1722, which was recovered in 2020 and differed by only three Single Nucleotide Polymorphisms (SNPs). No NDM-positive ST19 could be found in the National Center for Biotechnology Information (NCBI) database, and NBFE-164 showed a close genetic relationship with the other ST19 in this area. To sum up, we suggested the potential contributions of clonal spread and plasmid-mediated blaNDM transfer in CRSE dissemination. This study reported the complete genome of two blaNDM-carrying S. Typhimurium isolates, shedding new insights into the antimicrobial resistance mechanisms and dissemination patterns of the emerging CRSE.IMPORTANCENTS is one of the most common zoonotic pathogens that causes foodborne illnesses, while S. Typhimurium is one of the most common serovars. With the rising prevalence of multi-resistant Salmonella worldwide, carbapenems have emerged as the last-line antibiotics for treating severe bacterial infections. In this study, we reported the genomic characteristics of two carbapenem-resistant S. Typhimurium strains, which were recovered from two pediatric patients, carrying blaNDM-5 and blaNDM-13, providing new insights into the antimicrobial resistance deteriminants and transmission risk of blaNDM-positive NTS in China. We suggested the potential contributions of clonal spread and plasmid-mediated blaNDM transfer in CRSE dissemination. Future enhanced surveillance policy should mitigate CRSE spreading, and more importantly, clinical antimicrobial therapeutic regimens should be adjusted accordingly.

Prevalence and distribution of carbapenem-resistant Enterobacterales in companion animals: A nationwide study in the United States using commercial laboratory data

BACKGROUND

Carbapenem-resistant Enterobacterales (CRE) are a concern in both human and animal medicine globally. Despite extensive research in humans, limited data exist on CRE in companion animals, with a lack of nationwide prevalence estimates.

HYPOTHESIS/OBJECTIVES

To assess the occurrence and trends of CRE in cats and dogs across the United States by analyzing 4 years of commercial antimicrobial susceptibility testing (AST) data.

ANIMALS

Between 2019 and 2022, 477 426 ASTs were conducted on Enterobacterales isolates against imipenem. Isolates were derived from 379 598 dogs and 97 828 cats. Animal origin was not disclosed.

METHODS

In this retrospective study, antimicrobial susceptibility test data from IDEXX Laboratories were analyzed. Analysis included resistance estimations to imipenem stratified by sampling site, an assessment of resistance patterns over time and location, and the application of space-time cluster analysis to identify potential outbreaks. Antibiograms were produced for carbapenem-resistant isolates.

RESULTS

Susceptibility to imipenem was high, at 98.86%. Temporal analysis indicated stability in susceptibility, with an unexplained reduction in susceptible isolates in June 2019. Spatial analysis identified 2 high-risk clusters along the Western Coast (relative risk [RR]: 23.26; P < .001) and in Texas (RR: 10.72; P < .001) in that month. Three other clusters were found, in Missouri (RR: 39.55; P = .038), Florida (RR: 4.53; P < .001), and New York (RR: 9.20; P < .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

CRE are present at a low prevalence in dogs and cats across the United States. Variations in prevalence across patient-level and environmental factors highlight the need for tailored stewardship programs.

Hospital and municipal wastewater as a source of carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa in the environment: a review

The increase in the prevalence of carbapenem-resistant Gram-negative bacteria, in particular Acinetobacter baumannii (CRAB) and Pseudomonas aeruginosa (CRPA), poses a serious threat for public health worldwide. This article reviews the alarming data on the prevalence of infections caused by CRAB and CRPA pathogens and their presence in hospital and municipal wastewater, and it highlights the environmental impact of antibiotic resistance. The article describes the key role of antibiotic resistance genes (ARGs) in the acquisition of carbapenem resistance and sheds light on bacterial resistance mechanisms. The main emphasis was placed on the transfer of ARGs not only in the clinical setting, but also in the environment, including water, soil, and food. The aim of this review was to expand our understanding of the global health risks associated with CRAB and CRPA in hospital and municipal wastewater and to analyze the spread of these micropollutants in the environment. A review of the literature published in the last decade will direct research on carbapenem-resistant pathogens, support the implementation of effective preventive measures and interventions, and contribute to the development of improved strategies for managing this problem.

Public health aspects of Vibrio spp. related to the consumption of seafood in the EU

Vibrio parahaemolyticus, Vibrio vulnificus and non-O1/non-O139 Vibrio cholerae are the Vibrio spp. of highest relevance for public health in the EU through seafood consumption. Infection with V. parahaemolyticus is associated with the haemolysins thermostable direct haemolysin (TDH) and TDH-related haemolysin (TRH) and mainly leads to acute gastroenteritis. V. vulnificus infections can lead to sepsis and death in susceptible individuals. V. cholerae non-O1/non-O139 can cause mild gastroenteritis or lead to severe infections, including sepsis, in susceptible individuals. The pooled prevalence estimate in seafood is 19.6% (95% CI 13.7-27.4), 6.1% (95% CI 3.0-11.8) and 4.1% (95% CI 2.4-6.9) for V. parahaemolyticus, V. vulnificus and non-choleragenic V. cholerae, respectively. Approximately one out of five V. parahaemolyticus-positive samples contain pathogenic strains. A large spectrum of antimicrobial resistances, some of which are intrinsic, has been found in vibrios isolated from seafood or food-borne infections in Europe. Genes conferring resistance to medically important antimicrobials and associated with mobile genetic elements are increasingly detected in vibrios. Temperature and salinity are the most relevant drivers for Vibrio abundance in the aquatic environment. It is anticipated that the occurrence and levels of the relevant Vibrio spp. in seafood will increase in response to coastal warming and extreme weather events, especially in low-salinity/brackish waters. While some measures, like high-pressure processing, irradiation or depuration reduce the levels of Vibrio spp. in seafood, maintaining the cold chain is important to prevent their growth. Available risk assessments addressed V. parahaemolyticus in various types of seafood and V. vulnificus in raw oysters and octopus. A quantitative microbiological risk assessment relevant in an EU context would be V. parahaemolyticus in bivalve molluscs (oysters), evaluating the effect of mitigations, especially in a climate change scenario. Knowledge gaps related to Vibrio spp. in seafood and aquatic environments are identified and future research needs are prioritised.

Dissemination of clinical Escherichia coli strains harboring mcr-1, blaNDM-7 and siderophore-producing plasmids in a Chinese hospital

BACKGROUND

Carbapenem-resistant E. coli (CREco) pose a significant public health threat due to their multidrug resistance. Colistin is often a last-resort treatment against CREco; however, the emergence of colistin resistance gene mcr-1 complicates treatment options.

METHODS

Two E. coli strains (ECO20 and ECO21), recovered from hospitalized patients in distinct wards, exhibited resistance to carbapenems and colistin. Whole-genome sequencing and phenotypic characterization were employed to study resistance patterns, plasmid profiles, transferability of resistance and virulence genes, and siderophore production capabilities. Comparative genome analysis was used to investigate the genetic environment of mcr-1, blaNDM-7, and virulence clusters.

RESULTS

Both E. coli strains exhibited thr presence of both mcr-1 and blaNDM-7 genes, showing high resistance to multiple antibiotics. Genomic analysis revealed the clonal transmission of these strains, possessing identical plasmid profiles (pMCR, pNDM, and pVir) associated with colistin resistance, carbapenem resistance, and virulence factors. Conjugation experiments confirmed the transferability of these plasmids, indicating their potential to disseminate resistance and virulence traits to other strains. Comparative genomic analyses unveiled the distribution of mcr-1 (IncX4-type) and blaNDM (IncX3-type) plasmids across diverse bacterial species, emphasizing their adaptability and threat. The novelty of pVir indicates its potential role in driving the evolution of highly adaptable and pathogenic strains.

CONCLUSIONS

Our findings underscore the co-occurrence of mcr-1, blaNDM-7, and siderophore-producing plasmids in E. coli, which poses a significant concern for global health. This research is crucial to unravel the complex mechanisms governing plasmid transfer and recombination and to devise robust strategies to control their spread in healthcare settings.

Tackling Carbapenem Resistance and the Imperative for One Health Strategies-Insights from the Portuguese Perspective

Carbapenemases, a class of enzymes specialized in the hydrolysis of carbapenems, represent a significant threat to global public health. These enzymes are classified into different Ambler's classes based on their active sites, categorized into classes A, D, and B. Among the most prevalent types are IMI/NMC-A, KPC, VIM, IMP, and OXA-48, commonly associated with pathogenic species such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The emergence and dissemination of carbapenemase-producing bacteria have raised substantial concerns due to their ability to infect humans and animals (both companion and food-producing) and their presence in environmental reservoirs. Adopting a holistic One Health approach, concerted efforts have been directed toward devising comprehensive strategies to mitigate the impact of antimicrobial resistance dissemination. This entails collaborative interventions, highlighting proactive measures by global organizations like the World Health Organization, the Center for Disease Control and Prevention, and the Food and Agriculture Organization. By synthesizing the evolving landscape of carbapenemase epidemiology in Portugal and tracing the trajectory from initial isolated cases to contemporary reports, this review highlights key factors driving antibiotic resistance, such as antimicrobial use and healthcare practices, and underscores the imperative for sustained vigilance, interdisciplinary collaboration, and innovative interventions to curb the escalating threat posed by antibiotic-resistant pathogens. Finally, it discusses potential alternatives and innovations aimed at tackling carbapenemase-mediated antibiotic resistance, including new therapies, enhanced surveillance, and public awareness campaigns.

The European Union summary report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2021-2022

This report by the European Food Safety Authority and the European Centre for Disease prevention and Control, provides an overview of the main findings of the 2021-2022 harmonised Antimicrobial Resistance (AMR) monitoring in Salmonella spp., Campylobacter jejuni and C. coli from humans and food-producing animals (broilers, laying hens and fattening turkeys, fattening pigs and cattle under one year of age) and relevant meat thereof. For animals and meat thereof, AMR data on indicator commensal Escherichia coli, presumptive extended-spectrum beta-lactamases (ESBL)-/AmpC beta-lactamases (AmpC)-/carbapenemase (CP)-producing E. coli, and the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) are also analysed. Generally, resistance levels differed greatly between reporting countries and antimicrobials. Resistance to commonly used antimicrobials was frequently found in Salmonella and Campylobacter isolates from humans and animals. In humans, increasing trends in resistance to one of two critically antimicrobials (CIA) for treatment was observed in poultry-associated Salmonella serovars and Campylobacter, in at least half of the reporting countries. Combined resistance to CIA was however observed at low levels except in some Salmonella serovars and in C. coli from humans and animals in some countries. While CP-producing Salmonella isolates were not detected in animals in 2021-2022, nor in 2021 for human cases, in 2022 five human cases of CP-producing Salmonella were reported (four harbouring bla OXA-48 or bla OXA-48-like genes). The reporting of a number of CP-producing E. coli isolates (harbouring bla OXA-48, bla OXA-181, bla NDM-5 and bla VIM-1 genes) in fattening pigs, cattle under 1 year of age, poultry and meat thereof by a limited number of MSs (5) in 2021 and 2022, requires a thorough follow-up. The temporal trend analyses in both key outcome indicators (rate of complete susceptibility and prevalence of ESBL-/AmpC-producers in E. coli) showed an encouraging progress in reducing AMR in food-producing animals in several EU MSs over the last 7 years.