Antimicrobial Resistance Profile and Characterization of Beta-lactamase-producing Escherichia coli in Camels Reared from Laikipia County

Abstract

The abuse and misuse of antimicrobials in clinical and agricultural setups have led to an increased interaction of these agents with human, livestock, and environmental microbes. Camel husbandry management practices are hypothesized to be facilitating exposure to antibiotics, development of antimicrobial resistance (AMR), and spread of zoonotic microbes in Kenya’s Arid and Semi-Arid Lands (ASALs). Disruption in the ecology of microbial communities by antimicrobials in the camel population promotes the spread of antibiotic resistance genes. With increase in camel population by tenfold in the last decade, driven largely by land use changes and widespread use of camel products for nutritional, therapeutic, and cosmetic value, raises possibilities of Extended Spectrum Beta-lactamase (ESBL)-producing Escherichia coli (E. coli), in camels reared in animal production system. This present study aimed at assessing the antimicrobial susceptibility profile, detecting, and characterizing beta-lactamase producing E. coli recovered from camels. Fecal swabs were aseptically collected from 304 camels reared by pastoral communities (extensive production system), (n=137), and ranches (intensive production system), (n=167), and stored in Cary Blair transport media for processing. One hundred and twenty-three (123), E. coli isolates were isolated from fecal swabs of camels reared in the intensive and extensive livestock production. Among the E. coli (n=123), recovered, the highest resistance was observed in Cefaclor 35(28.46%), followed by Cefotaxime 20(16.26%), and Ampicillin12(9.76%). Four (4) ESBL-producing E. coli with multi-drug resistance phenotype harbored blaCTX-M-15 and blaCTX-M-27 genes were identified from these isolates and associated to phylogenetic group B1, B2, and D. Multiple variants of non-ESBL blaTEM gene variants were identified, majority of which were the blaTEM-1 and blaTEM-116 genes. In terms of AMR and beta-lactamase gene prevalence, there was no statistically significant difference between intensive and extensive camel rearing production systems (p-value = 0.61, 95% CI). This study's findings provide insight on the diverse variants of ESBL and non-ESBL producing genes in E. coli from camels in the farming practices. Furthermore, advocates for One Health approach in camel production in ASALs to understand antimicrobial resistance transmission mechanism, risk factors, and proper antimicrobial management practices in camel production systems within ASALs.