Escherichia coli isolates from commercial chicken meat and eggs cause sepsis, meningitis and urinary tract infection in rodent models of human infections

Abstract

The zoonotic potential of Escherichia coli from chicken-source food products is important to define for public health purposes. Previously, genotypic and phenotypic screening of E. coli isolates from commercial chicken meat and shell eggs identified some E. coli strains that by molecular criteria resembled human-source extraintestinal pathogenic E. coli (ExPEC). Here, to clarify the zoonotic risk of such chicken-source E. coli, we compared selected E. coli isolates from chicken meat and eggs, stratified by molecularly defined ExPEC status, to human-source ExPEC and to laboratory E. coli for virulence in rodent models of sepsis, meningitis and UTI, and evaluated whether specific bacterial characteristics predict experimental virulence. Multiple chicken-source E. coli resembled human-source ExPEC in their ability to cause one or multiple different ExPEC-associated infections. Swimming ability corresponded with urovirulence, K1 capsule corresponded with ability to cause neonatal meningitis, and biofilm formation in urine corresponded with ability to cause sepsis. In contrast, molecularly defined ExPEC status and individual genotypic traits were uncorrelated with ability to cause sepsis, and neither complement sensitivity nor growth in human urine corresponded with virulence in any infection model. These findings establish that chicken-derived food products contain E. coli strains that, in rodent models of multiple human-associated ExPEC infections, are able to cause disease comparably to human-source E. coli clinical isolates, which suggests that they may pose a significant food safety threat. Further study is needed to define the level of risk they pose to human health, which if appreciable would justify efforts to monitor for and reduce or eliminate them.

Three new serine-protease autotransporters of Enterobacteriaceae (SPATEs) from extra-intestinal pathogenic Escherichia coli and combined role of SPATEs for cytotoxicity and colonization of the mouse kidney

“…It has been shown that certain APEC strains are highly similar to human ExPEC and can belong to the same clonal groups and contain similar virulence gene profiles [2,6,9,11,12,14,24,25]. Previous reports have also tested APEC strains in the mouse UTI model [78][79][80][81]. QT598 is a serogroup O1 strain, which is a common serogroup of both APEC and human ExPEC strains, and is clonally related to some human ExPEC, further supporting verification of the role of SPATEs for this strain in a UTI model.…”

Phylogenetic Backgrounds and Virulence-Associated Traits of Escherichia coli Isolates from Surface Waters and Diverse Animals in Minnesota and Wisconsin

“…The high degree of PFGE profile similarity we identified between some of the present water and animal source ExPEC isolates and archival human clinical fecal isolates, particularly within familiar virulence-associated STs such as STc12, STc73, and STc131 (38), provides added genetic support for the hypothesis that these study isolates represent potential human pathogens. This hypothesis could be explored further by assessing the in vivo virulence capabilities of these isolates in animal models that mimic human extraintestinal infections (39,40).…”

Prevalence and Molecular Characteristics of Avian-Origin mcr-1-Harboring Escherichia coli in Shandong Province, China

“…E. coli is a common inhabitant of the vertebrate intestinal tract and warm-blooded animals (Van den bogaard and Stobberingh, 2000). Moreover, avian-origin E. coli might hold zoonotic potential to cause human infections (Mellata et al, 2018).…”