Comparative Characteristics and Zoonotic Potential of Avian Pathogenic Escherichia coli (APEC) Isolates from Chicken and Duck in South Korea

Abstract

Avian pathogenic Escherichia coli (APEC) causes colibacillosis, which is an economically important disease in the poultry industry worldwide. The present study investigated O-serogroups, phylogenetic groups, antimicrobial resistance, and the existence of virulence-associated genes (VAGs) and antimicrobial resistance genes in 125 APEC isolates between 2018 and 2019 in Korea. The phylogenetic group B2 isolates were confirmed for human-related sequence types (STs) through multi-locus sequence typing (MLST). O-serogroups O2 (12.5%) and O78 (10.3%) and phylogenetic group B1 (36.5%) and A (34.5%) were predominant in chicken and duck isolates, respectively. Out of 14 VAGs, iucD, iroN, hlyF, and iss were found significantly more in chicken isolates than duck isolates (p < 0.05). The resistance to ampicillin, ceftiofur, ceftriaxone, and gentamicin was higher in chicken isolates than duck isolates (p < 0.05). The multidrug resistance (MDR) rates of chicken and duck isolates were 77.1% and 65.5%, respectively. One isolate resistant to colistin (MIC 16 μg/mL) carried mcr-1. The B2-ST95 APEC isolates possessed more than 9 VAGs, and most of them were MDR (82.4%). This report is the first to compare the characteristics of APEC isolates from chickens and ducks in Korea and to demonstrate that B2-ST95 isolates circulating in Korea have zoonotic potential and pose a public health risk.

Isolation, Molecular Characterization, and Antibiotic Resistance of Avian Pathogenic Escherichia coli in Eastern China

“…In addition, we found a similar MDR frequency between chicken (100%) and duck (100%) isolates. This result was different from the recent study in South Korea which reported 77.1% in chicken isolates and 65.5% in duck isolates [ 48 ]. The high MDR rates in our study demonstrate the high antimicrobial resistance and the inappropriate use of certain antibiotics in farm animals in China [ 53 ].…”

“…In this study, the 15 tested virulence genes showed almost similar patterns in chicken and duck isolates. On the contrary, Jiyeon Jeong and coworkers reported that chicken isolates may have a higher virulence potential than duck isolates [ 48 ]. Our findings suggest that chicken and duck isolates may possess a similar potential for virulence genes.…”

Relationship between phylogenetic groups of Escherichia coli and Pathogenicity among Isolates from chickens with Colibacillosis and healthy chickens

“…APEC isolates obtained from diseased poultry occasionally belong to the phylogenetic group D in Thailand ( Thomrongsuwannakij et al, 2022 ) and groups A and D in Japan ( Asai et al , 2011 ; Ozaki et al, 2017 ), based on the original Clermont scheme. Recently, several studies focused on avian colibacillosis strains belonging to phylogroups B2 and F based on the revised Clermont scheme due to their zoonotic potential as an etiologic agent of extraintestinal infections in humans ( Jeong et al, 2021 ; Wang et al, 2021 ; Zhuge et al, 2021 ).…”

Antimicrobial Susceptibility and Detection of Virulence-Associated Genes in Escherichia coli Strains Isolated from Commercial Broilers

“…In birds, E. coli isolates containing virulence factors are designated as avian pathogenic E. coli (APEC), which cause avian colibacillosis, and together with uropathogenic E. coli (UPEC) and E. coli causing meningitis in the newborn (NMEC), they belong among the extra-intestinal E. coli (ExPEC) strains. Since all ExPEC strains present the same phylogenetic origin and a notable degree of overlap in serogroups, sequence types (STs), and virulence-associated genes, several studies have suggested their zoonotic potential [ 1 , 2 ].…”

“…Numerous studies on phylogenetic groups, virulence-associated genes, and antimicrobial resistance in APEC isolates from farm poultry derived from various colibacillosis have been conducted in many countries, to prevent drug-resistant pathogenic strains reaching consumer foodstuffs [ 2 ]. These pathogenic strains result generally from commensals by the acquisition of infectious capacity through horizontal transfer of virulence genes [ 5 ].…”