Silent dissemination of colistin-resistant Escherichia coli in South America could contribute to the global spread of the mcr-1 gene

Abstract

During a Brazilian multicentric antimicrobial resistance surveillance study, colistin resistance was investigated in 4,620 Enterobacteriaceae isolated from human, animal, food and environmental samples collected from 2000 to 2016. We present evidence that mcr-1-positive Escherichia coli has been emerging in South America since at least 2012, supporting a previous report on the possible acquisition of mcr-1-harbouring E. coli by European travellers visiting Latin American countries.

Identification of a novel plasmid-mediated colistin-resistance gene, mcr-2, in Escherichia coli, Belgium, June 2016

“…Since mcr-1 conferring plasmid-mediated colistin resistance was first detected in China, mcr-1 has been identified in 30 countries across five continents [14][15][16][17] (Figure 4). …”

Coexistence of mcr-1 and bla NDM-1 in Escherichia coli from Venezuela

“…In November 2015, however, a new plasmid-mediated colistin resistance mechanism, called MCR-1, was discovered (4). Since its first identification, mcr-1 from human, animal, food, and environmental origins has been widely reported (5)(6)(7). The coexistence of mcr-1 with a carbapenemase is especially worrisome, as therapeutic options in such cases are very limited.…”

MCR-1.6, a New MCR Variant Carried by an IncP Plasmid in a Colistin-Resistant Salmonella enterica Serovar Typhimurium Isolate from a Healthy Individual

“…Since the first report of plasmid pHNSHP45 carrying the mcr-1 gene (1), numerous retrospective studies have been performed worldwide to investigate the presence of this specific gene in strains isolated from environmental samples, food animals, food, and humans (2)(3)(4)(5)(6)(7)(8)(9)(10)(11), and the earliest evidence for its presence dates back to the 1980s (12). The mcr-1 gene was recently found to be carried by different plasmid replicon types, such as IncI2, IncHI2, IncP, IncFIP, and IncX4 (4,(13)(14)(15).…”