The Mobile Colistin Resistance Gene, mcr-1.1, Is Carried on IncX4 Plasmids in Multidrug Resistant E. coli Isolated from Rainbow Trout Aquaculture

Abstract

Colistin, a last resort antibiotic, is important for controlling infections with carbapenem-resistant Enterobacteriaceae. The recent emergence of mobile-colistin-resistance (mcr) genes has threatened the effectiveness of colistin. Aquaculture is hypothesized to be a major contributor to the evolution and dissemination of mcr. However, data on mcr in aquaculture are limited. Here, the occurrence of mcr-1 was assessed in Rainbow Trout in Lebanon, a country with developing antimicrobial stewardship and an established use of colistin for medical and farming purposes. mcr-1 was detected in 5 Escherichia coli isolated from fish guts. The isolates were classified as multidrug-resistant and their colistin minimum inhibitory concentration ranged between 16 and 32 μg/mL. Whole genome sequencing analysis showed that mcr-1 was carried on transmissible IncX4 plasmids and that the isolates harbored more than 14 antibiotic resistance genes. The isolates belonged to ST48 and ST101, which have been associated with mcr and can occur in humans and fish. The mcr-1-positive E. coli persisted in 6-day biofilms, but there was a potential fitness cost. Given the status of infrastructure in Lebanon, there is a high potential for the dissemination of mcr via aquatic environments. Urgent actions are needed to control mcr and to enhance antimicrobial stewardship in Lebanon.

WGS Analysis of Clonal and Plasmidic Epidemiology of Colistin-Resistance Mediated by mcr Genes in the Poultry Sector in Lebanon

“…A strength of our work refers to the identification of mcr-1 -bearing plasmids, which was almost absent from other studies in Lebanon ( Al-Mir et al, 2019 ; Hassan et al, 2020 ; Sourenian et al, 2020 ). With the single exception of one isolate where plasmid or chromosomal location was not clarified, all mcr-1 genes were detected on plasmids, mostly on IncX4 ( n = 36) but also on IncI2 ( n = 24).…”

“…Finally, mcr-1 has also been reported in human clinical isolates in Lebanon that had been collected as early as 2011 ( Al-Mir et al, 2019 ). The plasmidic location of the mcr-1 gene has, however, rarely been investigated in those studies: it was found located on an IncX4 plasmid in human isolates and in a rainbow trout isolate, and on IncX4 and IncI2 in water isolates ( Al-Mir et al, 2019 ; Hassan et al, 2020 ; Sourenian et al, 2020 ). Likewise, data on the bacterial population structure hosting mcr-1 -mediated colistin-resistance remain largely unknown.…”

Antimicrobial Resistance in Escherichia coli Strains Isolated from Humans and Pet Animals

“…According to Hassan et al [ 112 ], a last resort antibiotic is colistin. Colistin is crucial for managing infections with carbapenem-resistant Enterobacteriaceae .…”

First Nation-Wide Analysis of Food Safety and Acceptability Data in Lebanon

“…Food products are the number one exports in Lebanon, accounting for ~$1.7 billion in revenue [ 8 ]. However, Lebanon is currently struggling with wide-spread pollution, weakened infrastructure, political and civil unrest, and the most significant and debilitating economic crisis in its recent history [ 9 , 10 , 11 , 12 ]. Consequently, food safety and security issues in Lebanon have been on the rise with various cases of spoiled and expired food, fraud, and outbreaks that have received national attention [ 9 ].…”

“…Currently, there are a plethora of factors that contribute to the status of food safety in Lebanon, including (1) absence of national baseline data on chemical and microbiological food contaminants, (2) insufficient scientific and technical expertise in the field, (3) scant financial support, (4) poor foodborne illness/outbreak surveillance, (5) inconsistent governmental oversight, transparency, and implementation and enforcement of policies and laws, (6) overlapping and conflicting jurisdictions of governmental agencies that oversee food safety, and (7) weak awareness of safety procedures in small food businesses [ 9 ]. Furthermore, there is limited support for academic research on the prevalence and properties of food contaminants and subsequent control mechanisms [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. Taken together, these issues have left their mark on both the national economy and public health [ 33 ].…”