Species belonging to Enterobacter cloacae complex have been isolated in numerous environments and samples of various origins. They are also involved in opportunistic infections in plants, animals, and humans. Previous prospection in Guadeloupe (French West Indies) indicated a high frequency of E. cloacae complex strains resistant to third-generation cephalosporins (3GCs) in a local lizard population (Anolis marmoratus), but knowledge of the distribution and resistance of these strains in humans and the environment is limited. The aim of this study was to compare the distribution and antibiotic susceptibility pattern of E. cloacae complex members from different sources in a “one health” approach and to find possible explanations for the high level of resistance in non-human samples. E. cloacae complex strains were collected between January 2017 and the end of 2018 from anoles, farm animals, local fresh produce, water, and clinical human samples. Isolates were characterized by the heat-shock protein 60 gene-fragment typing method, and whole-genome sequencing was conducted on the most frequent clusters (i.e., C-VI and C-VIII). The prevalence of resistance to 3GCs was relatively high (56/346, 16.2%) in non-human samples. The associated resistance mechanism was related to an AmpC overproduction; however, in human samples, most of the resistant strains (40/62) produced an extended-spectrum beta-lactamase. No relation was found between resistance in isolates from wild anoles (35/168) and human activities. Specific core-genome phylogenetic analysis highlighted an important diversity in this bacterial population and no wide circulation among the different compartments. In our setting, the mutations responsible for resistance to 3GCs, especially in ampD, were diverse and not compartment specific. In conclusion, high levels of resistance in non-human E. cloacae complex isolates are probably due to environmental factors that favor the selection of these resistant strains, and this will be explored further.

Wastewater treatment plants are considered hot spots for antibiotic resistance. Most studies have addressed the impact on the aquatic environment, as water is an important source of anthropogenic pollutants. Few investigations have been conducted on terrestrial animals living near treatment ponds. We isolated extended-spectrum-β-lactamase Enterobacter cloacae complex-producing strains from 35 clinical isolates, 29 samples of wastewater, 19 wild animals, and 10 domestic animals living in the hospital sewers and at or near a wastewater treatment plant to study the dissemination of clinically relevant resistance through hospital and urban effluents. After comparison of the antibiotic-resistant profiles of E. cloacae complex strains, a more detailed analysis of 41 whole-genome-sequenced strains demonstrated that the most common sequence type, ST114 (n = 20), was present in human (n = 9) and nonhuman (n = 11) samples, with a close genetic relatedness. Whole-genome sequencing confirmed local circulation of this pathogenic lineage in diverse animal species. In addition, nanopore sequencing and specific synteny of an IncHI2/ST1/bla_CTX-M-15 plasmid recovered on the majority of these ST114 clones (n = 18) indicated successful worldwide diffusion of this mobile genetic element.

Between April 2018 and August 2019, a total of 135 strains of Enterobacter cloacae complex (ECC) were randomly collected at the University Hospital Center of Guadeloupe to investigate the structure and diversity of the local bacterial population. These nosocomial isolates were initially identified genetically by the hsp60 typing method, which revealed the clinical relevance of E. xiangfangensis (n = 69). Overall, 57/94 of the third cephalosporin-resistant strains were characterized as extended-spectrum-β-lactamase (ESBL) producers, and their whole-genome was sequenced using Illumina technology to determine the clonal relatedness and diffusion of resistance genes. We found limited genetic diversity among sequence types (STs). ST114 (n = 13), ST1503 (n = 9), ST53 (n = 5) and ST113 (n = 4), which belong to three different Enterobacter species, were the most prevalent among the 57 ESBL producers. The bla_CTXM-15 gene was the most prevalent ESBL determinant (56/57) and was in most cases associated with IncHI2/ST1 plasmid replicon carriage (36/57). To fully characterize this predominant bla_CTXM-15/IncHI2/ST1 plasmid, four isolates from different lineages were also sequenced using Oxford Nanopore sequencing technology to generate long-reads. Hybrid sequence analyses confirmed the circulation of a well-conserved plasmid among ECC members. In addition, the novel ST1503 and its associated species (ECC taxon 4) were analyzed, in view of its high prevalence in nosocomial infections. These genetic observations confirmed the overall incidence of nosocomial ESBL Enterobacteriaceae infections acquired in this hospital during the study period, which was clearly higher in Guadeloupe (1.59/1000 hospitalization days) than in mainland France (0.52/1,000 hospitalization days). This project revealed issues and future challenges for the management and surveillance of nosocomial and multidrug-resistant Enterobacter in the Caribbean.

Objectives: The Enterobacter cloacae complex is considered an important opportunistic pathogen. It comprises many members that remain difficult to delineate by phenotypic approaches. Despite its importance in human infection, there is a lack of information on associated members in other compartments. Here we report the first de novo assembled and annotated whole-genome sequence of a E. chengduensis strain isolated from the environment. Data description: ECC445 specimen was isolated in 2018 from a drinking water catchment point in Guadeloupe. It was clearly related to E. chengduensis species according to hsp60 typing and genomic comparison. Its whole-genome sequence is 5,211,280-bp long divided into 68 contigs, and presents a G + C content of 55.78%. This genome and associated datasets provided here will serve as a useful resource for further analyses of this rarely reported Enterobacter species.

Here, we describe the genome sequence of ECC486. This Enterobacter oligotrophicus strain was isolated from a wild Anolis marmoratus speciosus specimen, a lizard endemic to the territory of Guadeloupe (French West Indies). Its draft genome sequence consists of 40 contigs and contains a total of 4,504,233 bp, with a G+C content of 54.1%.

Carbapenemase-producing Enterobacterales (CPE) have been designated by the World Health Organization as critical global priority pathogens. Their widespread dissemination and nosocomial outbreaks pose a major public health threat. This study examined the transmission patterns and genetic characteristics of CPE isolated in New Caledonia between 2013 and 2022. A total of 214 CPE isolates were collected, comprising 199 non-duplicate clinical isolates from 164 patients and 15 environmental isolates from hospital surfaces. Isolates were characterized using phenotypic methods and whole-genome sequencing. Among clinical isolates, the most prevalent genera was Enterobacter (n = 68; 34%) and Klebsiella (n = 50; 25%), with 194 isolates (98%) harbouring IMP-type carbapenemases. WGS of 89 selected CPE revealed the predominance of the bla_IMP-4 gene (n = 82; 92%). This gene was primarily associated with IncM2-type plasmids carrying a class 1 integron, identified in 65 sequenced isolates. Long-read sequencing resolved these plasmids into seven distinct variants, differentiated by integron structures and a 9305-bp insertion. Genomic, phenotypic, and epidemiological triangulation have identified 12 hospital spread events, with 10 linked to IMP-4 IncM2 plasmids, whose transferability is confirmed by conjugation assays. These results highlighted the pivotal role of plasmid-mediated dissemination in CPE spread and emphasize the urgency of enhanced surveillance to curb silent transmission. The study provided critical insights for targeted infection control strategies in New Caledonia healthcare system, with broader implications for regional antimicrobial resistance containment.