Escherichia fergusonii Harboring IncHI2 Plasmid Containing mcr-1 Gene: A Novel Reservoir for Colistin Resistance in Brazil

Avian strains of emerging pathogen Escherichia fergusonii are phylogenetically diverse and harbor the greatest AMR dissemination potential among different sources: Comparative genomic evidence

“…Though the organism has been reported from various parts of the world, including Asia , Europe (Toualbia et al, 2018), North and South Americas (Lindsey et al, 2017;Pontes et al, 2021), and Africa (Ben Yahia et al, 2020), they have hardly been reported from India, and the current report, to the best of our knowledge, is the first comprehensive genomic study from India.…”

“…Besides clinical conditions, the organisms were also isolated from the feces of a male patient with leukemia in Italy (Savini et al, 2009). Among non-human sources, E. fergusonii has commonly been identified from avian species including wild and migratory birds (Ben Yahia et al, 2020;Shah et al, 2022), broilers (Forgetta et al, 2012;Oh et al, 2012;Simmons et al, 2016;Pontes et al, 2021;Saha et al, 2021), ducks , and a case of fibro-necrotic typhlitis in ostrich (Herráez et al, 2005). In other animals, E. fergusonii has been identified from diarrheic caprines (Hariharan, 2009) and equines (Weiss et al, 2011), as well as from cases of pneumonia in bovines (Rimoldi and Moeller, 2013).…”

“…Concerns have been raised about increasing multidrug resistance among E. fergusonii strains (Savini et al, 2008;Lagacé-Wiens et al, 2010;Rayamajhi et al, 2011). The presence of AMR genes of clinical importance, such as extended spectrum beta-lactamases (ESBLs) (Lagacé-Wiens et al, 2010), carbapenemases (Ben Yahia et al, 2020), and mobilized colistin resistance (mcr) genes (Adesina et al, 2019;Pontes et al, 2021; among E. fergusonii strains has earned global attention. In addition to harboring AMR genes, previous reports have suggested that the organism can possess multiple virulence factors, such as heat-labile toxin (LT), heat-stable toxin (STa), as well as eae 1 https://lpsn.dsmz.de/species/escherichia-fergusonii gene (Rayamajhi et al, 2011;Oh et al, 2012).…”

Colistin-resistant Escherichia coli belonging to different sequence types: genetic characterization of isolates responsible for colonization, community- and healthcare-acquired infections

“…Resistance to colistin usually rises from selective pressure due to the use of polymyxins 2 . In Brazil, colistin was widely used as a growth promoter in animal production until 2016, when it was banned 26 due to identification of plasmid-mediated colistin-resistant isolates in the country. It is important to point out that the prevalence of colistin-resistance isolates can be underestimated, as colistin-susceptibility is not routinely tested in outpatients’ clinical samples.…”

“…Up to now, the mcr-1 gene is the most frequent plasmid-mediated colistin-resistance gene reported in Brazil 26 , 27 . It has been described in Salmonella enterica isolated from poultry meat 21 , from food 27 , and in E. coli from cattle and humans 28 , 29 and Klebsiella pneumoniae from humans 29 .…”