AUTHOR=Hayer Shivdeep Singh , Casanova-Higes Alejandro , Paladino Eliana , Elnekave Ehud , Nault Andre , Johnson Timothy , Bender Jeff , Perez Andres , Alvarez Julio 

TITLE=Global Distribution of Extended Spectrum Cephalosporin and Carbapenem Resistance and Associated Resistance Markers in Escherichia coli of Swine Origin – A Systematic Review and Meta-Analysis

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.853810

DOI=10.3389/fmicb.2022.853810

ISSN=1664-302X

ABSTRACT=<p>Third generation cephalosporins and carbapenems are considered critically important antimicrobials in human medicine. Food animals such as swine can act as reservoirs of antimicrobial resistance (AMR) genes/bacteria resistant to these antimicrobial classes, and potential dissemination of AMR genes or resistant bacteria from pigs to humans is an ongoing public health threat. The objectives of this systematic review and meta-analysis were to: (1) estimate global proportion and animal-level prevalence of swine <italic>E. coli</italic> phenotypically resistant to third generation cephalosporins (3GCs) and carbapenems at a country level; and (2) measure abundances and global distribution of the genetic mechanisms that confer resistance to these antimicrobial classes in these <italic>E. coli</italic> isolates. Articles from four databases (CAB Abstracts, PubMed/MEDLINE, PubAg, and Web of Science) were screened to extract relevant data. Overall, proportion of <italic>E. coli</italic> resistant to 3GCs was lower in Australia, Europe, and North America compared to Asian countries. Globally, &lt;5% of all <italic>E. coli</italic> were carbapenem-resistant. Fecal carriage rates (animal-level prevalence) were consistently manifold higher as compared to pooled proportion of resistance in <italic>E. coli</italic> isolates. <italic>bla</italic><sub><italic>CTX–M</italic></sub> were the most common 3GC resistance genes globally, with the exception of North America where <italic>bla</italic><sub><italic>CMY</italic></sub> were the predominant 3GC resistance genes. There was not a single dominant <italic>bla</italic><sub><italic>CTX–M</italic></sub> gene subtype globally and several <italic>bla</italic><sub><italic>CTX–M</italic></sub> subtypes were dominant depending on the continent. A wide variety of carbapenem-resistance genes (<italic>bla</italic><sub>NDM–, VIM–, IMP–, OXA–48</sub>, <sub>and</sub><sub>KPC–</sub>) were identified to be circulating in pig populations globally, albeit at very-low frequencies. However, great statistical heterogeneity and a critical lack of metadata hinders the true estimation of prevalence of phenotypic and genotypic resistance to these antimicrobials. Comparatively frequent occurrence of 3GC resistance and emergence of carbapenem resistance in certain countries underline the urgent need for improved AMR surveillance in swine production systems in these countries.</p>