Antimicrobial-Resistant Escherichia coli Strains and Their Plasmids in People, Poultry, and Chicken Meat in Laos.

Aline I Moser,Christoph Hatz,Esther Kuenzli,Andrea Endimiani,Edgar I Campos-Madueno,Thomas Büdel,Manivanh Vongsouvath,Sayaphet Rattanavong

doi:10.3389/fmicb.2021.708182

Abstract

Antimicrobial resistant (AMR) Enterobacterales are widely distributed among the healthy population of the Indochinese peninsula, including Laos. However, the local reservoir of these pathogens are currently not known and possible sources such as agricultural settings and food have rarely been analyzed. In this work, we investigated the extended-spectrum cephalosporin- (ESC-) and colistin-resistant Escherichia coli strains (CST-R-Ec) isolated from the gut of local people, feces of poultry, and from chicken meat (60 samples each group) in Laos. Whole-genome sequencing (WGS) analysis based on both short- and long-read sequencing approaches were implemented. The following prevalence of ESC-R-Ec and CST-R-Ec were recorded, respectively: local people (70 and 15%), poultry (20 and 23.3%), and chicken meat (21.7 and 13.3%). Core-genome analysis, coupled with sequence type (ST)/core-genome ST (cgST) definitions, indicated that no common AMR-Ec clones were spreading among the different settings. ESC-R-Ec mostly possessed blaCTX–M–15 and blaCTX–M–55 associated to ISEcp1 or IS26. The majority of CST-R-Ec carried mcr-1 on IncX4, IncI2, IncP1, and IncHI1 plasmids similar or identical to those described worldwide; strains with chromosomal mcr-1 or possessing plasmid-mediated mcr-3 were also found. These results indicate a high prevalence of AMR-Ec in the local population, poultry, and chicken meat. While we did not observe the same clones among the three settings, most of the blaCTX–Ms and mcr-1/-3 were associated with mobile-genetic elements, indicating that horizontal gene transfer may play an important role in the dissemination of AMR-Ec in Laos. More studies should be planned to better understand the extent and dynamics of this phenomenon.

Highlights

Gut colonization with extended-spectrum cephalosporinresistant Enterobacterales (ESC-R-Ent) is a major health threat worldwide, as these bacteria represent a risk for subsequent difficult-to-treat extraintestinal infections (Karanika et al, 2016)
Fifty-one (85%) subjects resulted colonized at gut level with Antimicrobial resistant (AMR)-Ec; in particular, 42 (70%) carried extended-spectrum cephalosporin- (ESC-)R-Ec, while 9 (15%) possessed CST-R-Ec
Our results indicate that the prevalence of AMR-Ec in people in the community, poultry, and chicken meat is high, but still does not reach the concerning rates reported from the neighboring countries

Summary

Introduction

Gut colonization with extended-spectrum cephalosporinresistant Enterobacterales (ESC-R-Ent) is a major health threat worldwide, as these bacteria represent a risk for subsequent difficult-to-treat extraintestinal infections (Karanika et al, 2016). While studies from surrounding countries indicated high prevalence rates of ESC-R Escherichia coli (ESCR-Ec) in poultry and chicken meat, data for Laos does not exist (Ueda et al, 2015; Nguyen Do et al, 2016; Tansawai et al, 2019b). Little is known about the possible transfer of AMR pathogens from these reservoirs to humans (Ueda et al, 2015). In this context, a multifaceted One Health approach using state-of-the-art molecular methodologies is essential to understand and try limiting the spread of antimicrobial resistance (Kim and Cha, 2021). Studies implementing wholegenome sequencing (WGS) to characterize AMR-Ec collected simultaneously from different settings and in the same region are still lacking

Methods

Results

Conclusion