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bioRxiv · 10.1101/2024.09.22.614308

One Health assessment of poultry and cattle farms as reservoirs for ESBL-producing Escherichia coli

Abstract

BACKGROUNDUnregulated use of antibiotics in animal food production leads to the emergence of multidrug resistant bacteria, notably extended-spectrum beta-lactamases producing Escherichia coli (ESBL E. coli). ESBLs severely limit treatment options and pose a significant threat to public health. Investigating the potential role of livestock and poultry farms in harboring ESBL E. coli is crucial, given the prevalence of ESBL E. coli in humans, animals, and the environment, following the One Health framework. OBJECTIVESThe aim of this study was to assess and compare the potential contribution of cattle and poultry farms along with their respective human handlers to the emergence and spread of ESBL E. coli following One Health approach. METHODSTwenty cattle and twenty poultry farms were surveyed in Ludhiana, India to determine antibiotic usage, prevalent diseases in the farms. Animal faeces/poultry droppings, handler hand swabs, and stool samples were examined for the presence of ESBL E. coli. The isolates were examined for their susceptibility to 16 antibiotics and for the presence of selected antimicrobial resistance genes, including ESBL genes. Generalized linear mixed models were applied to investigate variations in the prevalence of ESBL E. coli associated with farm animal species, farm practices, and farm biosecurity measures. RESULTSOur findings revealed a higher prevalence of ESBL E. coli in poultry farms (53.75%) than in cattle farms (40.72%) and overall lower prevalence (12%) in human handlers. Of the total isolates, 86.52% were multidrug resistant, and 93.91% showed a high multiple antibiotic resistance (MAR) index (>0.2). Isolates from poultry farms exhibited a higher level of resistance with 97% of isolates exhibiting multidrug resistance, 100% isolates with MAR index of more than 0.2, and 90.70% carrying the blaCTXM gene. CONCLUSIONOur findings highlight cattle and poultry farms as potential reservoirs for multidrug-resistant and ESBL E. coli, contributing to the rising environmental burden of antibiotic resistance genes. This emphasizes the urgency of limiting antibiotic use in animal farming, especially in poultry production, to address the escalating problem of antibiotic resistance and protect both animal and human health.

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Malik, H., Singh, R., Kaur, S., Parmar, N., Tyagi, A., Aulakh, R. S., Gill, J. P. S.. 2024-09-22. One Health assessment of poultry and cattle farms as reservoirs for ESBL-producing Escherichia coli. https://doi.org/10.1101/2024.09.22.614308

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