Molecular epidemiology of carbapenemase-producingEscherichia colifrom duck farms in south-east coastal China

Abstract

Objectives To determine the dissemination and molecular characteristics of NDM-producing Escherichia coli strains from duck farms in south-east coastal China and their threats to human health. Methods A total of 232 NDM-producing E. coli were recovered from 1505 samples collected from 25 duck farms and their surrounding environments in five provinces in China. Resistance genes were confirmed using PCR. Genomic characteristics of the carbapenemase-producing isolates were determined by WGS and bioinformatic analysis. Results The rate of NDM-positive E. coli detected in samples from the five provinces ranged from 3.7% to 28.5%. There was substantial variation in the prevalence of NDM-positive E. coli from different duck farms in each province studied. Three variants (blaNDM-1, blaNDM-4 and blaNDM-5) were found in 232 NDM-positive E. coli; blaNDM-5 (94.8%, 220/232) was the most prevalent. WGS analysis indicated that ST746, ST48, ST1011 and ST167 E. coli isolates were prevalent in the current study and poultry was likely the primary reservoir for NDM-positive ST746 and ST48 E. coli in China. Phylogenomic analysis showed that NDM-positive E. coli isolates from ducks were closely related to those of human origin. In addition, WGS analysis further revealed that blaNDM co-existed with other antibiotic resistance genes, conferring resistance to nine classes of antimicrobials. Conclusions This study revealed that ducks farm in China are an important reservoir for NDM-positive E. coli and STs of the isolates showed obvious distinctive diversities in geographical distribution. The distribution and spread of NDM-positive E. coli in duck farms poses a threat to public health.

Molecular Epidemiology of Fosfomycin Resistant E. coli from a Pigeon Farm in China

“…The fosfomycin-resistant E. coli were investigated by XbaI pulsed field electrophoresis (PFGE) and the locations of the fosfomycin resistance genes in the original isolates were determined by S1-PFGE mapping and Southern blot analysis, as described previously [19]. The PFGE patterns were analysed using a dendrogram of per cent similarity calculated with Dice coefficients using a cut-off of 80% [20]. The transferability of fosfomycin resistance genes was determined by the filter mating method using streptomycin-resistant E. coli C600 as a recipient strain, in accordance with a previous study [19].…”

Co-Occurrence of NDM-9 and MCR-1 in a Human Gut Colonized Escherichia coli ST1011

“…It is worthy to note that NDM-producing E. coli ST-1011 is prevalent in duck farms in southeast coastal China. 18 A previous study conducted in Lebanon found that ST1011 was one of the most widely identified clones associated with mcr-1-carrying E. coli and to the poultry sector. Our work further highlights the cooccurrence of NDM-9 and MCR-1 in E. coli ST1011 from https://doi.org/10.2147/IDR.S321732…”

The Emergence and Molecular Characteristics of New Delhi Metallo β-Lactamase-Producing Escherichia coli From Ducks in Guangdong, China

“…ST156 and ST648 have been associated with the dissemination of bla NDM−5 and mcr-1 -producing E. coli isolates (Yang et al, 2016 ). The bla NDM -positive ST746 and ST354 prevalent in ducks and poultry have become a primary reservoir for bla NDM -positive ST746 E. coli isolates in China (Wang et al, 2021 ). Phylogenomic analysis found that two of the isolates that were recovered from a single sample possessed different genomes, which indicates the development of diversity in the population of bla NDM -positive E. coli isolates from ducks.…”

“…Of note, mcr-1 , conferring resistance to the last-resort antibiotic colistin, was detected in 22 bla NDM -positive E. coli isolates. Some recent studies have reported that bla NDM and mcr-1 coproducing E. coli isolates were recovered from chicken (37/739, 5.0%), swine (16/105, 15.2%), and duck (11/92, 12.0%) farms (Kong et al, 2017 ; Wang et al, 2017 , 2021 ). There was also a high incidence of the co-harboring of mcr-1 and bla NDM in chickens (21/78, 26.9%) (Liu et al, 2017 ).…”

“…Although we previously reported that the rate of bla NDM -positive E. coli isolates at three duck farms in Guangdong was significantly higher than four other provinces in China, the sample collected was limited in western Guangdong province (Wang et al, 2021 ). Thus, in this study, we furthermore examined the epidemiology and molecular characterization of bla NDM -positive E. coli isolates recovered from ducks in representative areas for breeding ducks of Guangdong, China.…”