Occurrence of Phenotypic Multidrug-Resistant <i>E. coli</i> in Kentucky (USA) Surface Waters and Exploration of Sentinel Antibiotics for One Health Surveillance.
MDR E. coli was found in Kentucky surface waters, with 25% showing resistance from tetracycline-treated media, raising concerns for public health surveillance.
Where it sits
this study against the rest of the tesofensine corpusSummary and findings
This study measured the occurrence of multidrug-resistant (MDR) E. coli in surface waters of Kentucky, focusing on non-susceptibility to tetracycline. Samples were collected from 47 sites between 2022 and 2024. The findings indicated a significant prevalence of MDR phenotypes among the isolates.
Abstract
<b>Background/Objectives</b>: Antimicrobial resistance (AMR) is a global public health threat, and surface waters may serve as surveillance locations for multidrug-resistant (MDR) bacteria within communities. This study explored MDR <i>E. coli</i> in Kentucky (USA) surface waters, primarily evaluating non-susceptibility to tetracycline, for assessing MDR associations. <b>Methods</b>: Surface water samples were collected from 47 sites in East-Central Kentucky during 2022 and 2024. Isolates were obtained using selective differential media, with and without tetracycline (TE) supplementation, targeting <i>E. coli</i> and TE-resistant <i>E. coli.</i> Species identification and antimicrobial susceptibility testing against 21 antibiotics representing 13 categories was performed with recovered presumptive <i>E. coli</i> isolates. MDR was defined as non-susceptibility to at least one antibiotic in three or more antimicrobial categories. <b>Results</b>: Of 151 isolates, 130 (86%) were identified as <i>E. coli</i>. Overall, 25% and 13% of recovered <i>E. coli</i> isolates from media with and without TE had MDR phenotypes, respectively, which included one isolate with non-susceptibility to 10 of 12 designated antibiotic categories. MDR prevalence was higher among incidentally recovered <i>Enterobacter</i> spp. (100%) than <i>E. coli</i>. TE non-susceptibility occurred in 100% and 18% of <i>E. coli</i> isolates recovered from TE-treated and untreated media, respectively. Ampicillin non-susceptibility occurred in 28% and 16% of <i>E. coli</i> isolates from TE-treated and untreated media. Among this non-random set of recovered isolates, ampicillin and cefazolin non-susceptibility demonstrated potential for MDR <i>E. coli</i> prediction. TE-treated media did not significantly improve MDR <i>E. coli</i> recovery. <b>Conclusions</b>: MDR <i>E. coli</i> and one potentially extensively drug-resistant (XDR) <i>E. coli</i> isolate were recoverable from Kentucky surface waters. Ampicillin and cefazolin non-susceptibility demonstrated potential as sentinel markers for informing screening media development for AMR surveillance in Kentucky waters.