Occurrence and Characteristics of Extended-Spectrum β-Lactamase-Producing Escherichia coli from Dairy Cattle, Milk, and Farm Environments in Peninsular Malaysia

Abstract

The emergence and spread of antimicrobial resistance genes and resistant bacteria do not recognize animal, human, or geographic boundaries. Addressing this threat requires a multidisciplinary approach involving human, animal, and environmental health (One Health) sectors. This is because antimicrobial agents used in veterinary medicine have been reported to be the same or similar to those in human medicine use. Extended-spectrum β-lactamase (ESBL) E. coli is a growing public health problem worldwide, and the agri-food industry is increasingly becoming a source of clinically important ESBL bacteria. Accordingly, the aim of this study was to investigate the occurrence and characteristics of ESBL-producing E. coli from dairy cattle, milk, and the farm environment. E. coli isolates were identified by their 16sRNA, and their ESBL production was confirmed using ESBL–CHROMagar media and the double disk diffusion method. Genotypes of ESBL producers were characterized using multiplex polymerase chain reaction (mPCR) assay. It was found that 18 (4.8%) of the total samples were positive for ESBL-producing E. coli. Of these, 66.7% were from milk, and 27.8% and 5.5% were from the farm environment and faecal samples, respectively. Predominant ESBL genotypes identified were a combination of both TEM and CTX-M in eight out of 18 (44.4%) isolates. Four (22.2%) isolates produced the CTX-M gene, two (11.1%) isolates produced the TEM gene, and four (22.2%) remaining isolates produced the ESBL genes other than TEM, SHV, CTX-M, and OXA. The SHV and OXA gene were not detected in all 18 isolates. In all, there were four profiles of genetic similarity. The occurrence of these genotypes in indicator organisms from dairy cattle, milk, and the farm environment further re-enforced the potential of food-animals as sources of ESBL-producing E. coli infection in humans via the food chain. Thus, there is the need for the adoption of a tripartite One Health approach in surveillance and monitoring to control antimicrobial resistance.

Mobile Antimicrobial Resistance Genes in Probiotics

“…In 15 samples, E. coli -originated contigs harboured the gene TEM-116 . Plasmid origin is a common feature of ESBL genes such as TEM-116 according to several publications and is often referred to as a feature to facilitate their quick spread [ 91 , 92 , 93 ]. In the E. coli isolate sample s15, one contig had the marA and marR genes.…”

Diversity of Plasmids and Genes Encoding Resistance to Extended-Spectrum β-Lactamase in Escherichia coli from Different Animal Sources

“…These authors were able to confirm the bla ESBL genes transferred by conjugation as bla CTX-M-14 , bla CTX-M-15 , and bla TEM-20 . Others have used the two-step approach, as we did in this study, to identify and confirm ESBL producing E. coli [ 11 , 17 , 38 , 39 ]. Other studies have also found low numbers of ESBL producing E. coli in farm animals.…”

“…All isolates classified as intermediate or resistant using CLSI criteria (≤17 mm) to cefoxitin were suspected to be AmpC producers [ 36 ]. Based on the results of the phenotypic test, strains designed as putative ESBL producers were further analyzed by PCR for genes encoding ESBL genotypes: TEM, OXA, SHV, and CTX-M [ 37 , 38 , 39 , 40 , 41 ]. A strain of ESBLs-producing Klebsiella pneumoniae (ATCC 700603) was used as positive control for ESBLs gene screening as well as standard strain Escherichia coli (ATCC 25922).…”

Mobile antimicrobial resistance genes in probiotics

“…Plasmid origin is a common feature of ESBL genes such as TEM-116 according to several publications and is often referred to as a feature to facilitate their quick spread. [74][75][76] In the E. coli isolate sample s15, one contig had the marA and marR genes. These widespread multiple antibiotic resistance genes had been identified on plasmids before.…”