Caracterização molecular de Escherichia coli multirresistente na interface humano- animal-ambiental: uma abordagem One Health

Abstract

In the context of the One Health approach, microorganisms such as Escherichia coli have received increasing attention due to their widespread presence at the human-animal-environment interface and their ability to disseminate antimicrobial resistance genes, highlighting their role as resistance vectors. The aim of this study was to investigate the clonal dissemination of resistant E. coli isolated from the human-animal-environment interface, characterizing their resistance and virulence genes, as well as sequence types (STs), in order to evaluate their role in the circulation of these strains from the perspective of the One Health approach. This study adopted two complementary approaches. In the first, the clonal dissemination of E. coli was evaluated by PFGE using 21 isolates from humans, animals, and environments (sewage). The strains showed high resistance to β-lactams (penicillins and 2nd to 4th generation cephalosporins, monobactams), followed by quinolones, while resistance to aminoglycosides, carbapenems, and tetracyclines/glycylcyclines was low or absent. PFGE analysis identified multiple pulsotypes (A–H) among the isolates, with pulsotype B observed in humans and swine carcasses, pulsotype H in humans and in a canine sample, and pulsotype D in humans, animals, and sewage. In the second approach, 17 genomes were sequenced and analyzed for resistome, viruloma, sequence types (STs), and phylogeny. Thirty-six antimicrobial resistance genes were identified, with mutations associated with quinolone resistance standing out in 53% of the samples. Sixty-four virulence genes were identified, with the most prevalent being csgA, fdeC, fimH, gad, hlyE, nlpl, terC, yehA, yehB, yehC, yehD, and yghJ. Virulence determinants associated with adhesion, iron acquisition, and immune evasion, including lpfA, sitA, iss, traT, and ompT, were detected in human, animal, food, and environmental sources. Among the sequence types (STs) analyzed, ST131 and ST224 stood out, with the former found in four human isolates and the latter present in humans, animals, and the environment, sharing adhesion genes. ST10, identified in an environmental sample, showed low pathogenicity and an absence of resistance genes. Gene co-occurrence analysis revealed that virulence factors predominated in the genetic associations, but that resistance and virulence genes also coexist in several isolates, evidencing the circulation of potentially pathogenic and multidrug-resistant clones at the human-animal-environment interface. The findings reinforce the importance of integrated surveillance and the One Health approach in controlling the spread of multidrug-resistant and potentially pathogenic E. coli. In general, we characterized the genomic profile of E. coli strains from multiple sources and demonstrated their ability to harbor various determinants of resistance and virulence. These results emphasize that antimicrobial resistance is a dynamic, complex, and interconnected phenomenon across different environments. The circulation of the same clones among humans, animals, food, and the environment highlights the interconnectedness within the One Health context. Therefore, this study is important for formulating new surveillance strategies to prevent the spread of high-risk strains across different ecological niches.