Antimicrobial Resistance of Escherichia coli and Salmonella isolated from Raw Retail Broiler Chicken Carcasses in Zambia

Abstract

Background Antimicrobial resistance (AMR) of foodborne pathogens is of public health concern, especially in developing countries such as Zambia. This study was undertaken to determine the antimicrobial resistance profiles of Escherichia coli (E. coli) and Salmonella isolated from raw retail broiler chicken carcasses purchased from open and supermarkets in Zambia.Results A total of 189 E. coli and five Salmonella isolates were isolated. Identification and confirmation of the isolates were done using Analytical Profile Index (API 20E) (Biomerieux®) and 16S rRNA sequencing. Antimicrobial susceptibility tests (AST) were performed using the Kirby Bauer disk diffusion technique using a panel of 10 antibiotics. Multiplex PCR was used to determine the presence of three target genes encoding for resistance: tetA, Sul1 and blaCTX-M. WHONET 2018 software was used to analyse AST results. The E. coli isolates were mostly resistant to tetracycline (79.4%), ampicillin (51.9%), and trimethoprim/sulfamethoxazole (49.7%). Two of the five Salmonella isolates were resistant to at least one antibiotic. Forty- seven (45.2%) of the 104 isolates that were screened for the presence of the resistant genes possessed at least one of the targeted resistance genes.Conclusion This study has demonstrated the presence of AMR E. coli and Salmonella on raw retail broiler chicken carcasses from open and supermarkets, which is of public health concern.

Detection of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Enterobacteriaceae from Diseased Broiler Chickens in Lusaka District, Zambia

“…Over the past few years, AMR among the Enterobacteriaceae family has skyrocketed worldwide [ 19 ]. Studies pertaining to AMR have frequently been reported in E. coli and Salmonella from healthy chickens [ 2 , 20 ]. In this study, the most predominant species isolated was Enterobacter (43/103, 47%), which showed multidrug resistance to tetracyclines, sulphonamides, ampicillin, and amoxicillin.…”

“…This could be attributed to the presence of the genes on the same plasmid, as reported previously in Lusaka, Zambia [ 29 ], and in rural Nepal, where E. coli co-harboured the genes bla CTX-M and bla TEM [ 30 ]. Studies performed in Zambia reported a 13% prevalence of bla CTX-M in E. coli isolated from market-ready chickens [ 2 ]. Another study performed on commercial poultry farms in Zambia’s Copperbelt Province revealed 12.8% occurrence of bla CTX-M in Salmonella [ 10 ].…”

“…Therefore, understanding the zoonotic transmission of poultry-associated ESBLs requires a multipronged approach that considers both healthy and diseased chickens. In Zambia, most studies have focused on non-pathogenic bacteria isolated from asymptomatic chickens [ 2 , 9 , 10 ], leaving a gap in the ESBL status among sick chickens. Thus, this study was undertaken to estimate antimicrobial usage, isolate bacterial pathogens, and confirm the presence of ESBL-encoding genes by PCR and sequencing in bacteria isolated from poultry.…”

“…The chicken population is estimated to be 94 million broilers, 15 million village chickens, and 5.8 million layers [1]. Moreover, poultry products in Zambia, like in other developing African countries, form an integral part of the human diet in many households, as they are cheaper source of animal protein and are easier to produce compared with other foods of animal origin [2,3].…”