Spread of avian pathogenic Escherichia coli ST117 O78:H4 in Nordic broiler production

Abstract

Background Escherichia coli infections known as colibacillosis constitute a considerable challenge to poultry farmers worldwide, in terms of decreased animal welfare and production economy. Colibacillosis is caused by avian pathogenic E. coli (APEC). APEC strains are extraintestinal pathogenic E. coli and have in general been characterized as being a genetically diverse population. In the Nordic countries, poultry farmers depend on import of Swedish broiler breeders which are part of a breeding pyramid. During 2014 to 2016, an increased occurrence of colibacillosis on Nordic broiler chicken farms was reported. The aim of this study was to investigate the genetic diversity among E. coli isolates collected on poultry farms with colibacillosis issues, using whole genome sequencing.MethodsHundred and fourteen bacterial isolates from both broilers and broiler breeders were whole genome sequenced. The majority of isolates were collected from poultry with colibacillosis on Nordic farms. Subsequently, comparative genomic analyses were carried out. This included in silico typing (sero- and multi-locus sequence typing), identification of virulence and resistance genes and phylogenetic analyses based on single nucleotide polymorphisms.ResultsIn general, the characterized poultry isolates constituted a genetically diverse population. However, the phylogenetic analyses revealed a major clade of 47 closely related ST117 O78:H4 isolates. The isolates in this clade were collected from broiler chickens and breeders with colibacillosis in multiple Nordic countries. They clustered together with a human ST117 isolate and all carried virulence genes that previously have been associated with human uropathogenic E. coli.ConclusionsThe investigation revealed a lineage of ST117 O78:H4 isolates collected in different Nordic countries from diseased broilers and breeders. The data indicate that the closely related ST117 O78:H4 strains have been transferred vertically through the broiler breeding pyramid into distantly located farms across the Nordic countries.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-3415-6) contains supplementary material, which is available to authorized users.

Characterization and rapid identification of phylogroup G in Escherichia coli, a lineage with high virulence and antibiotic resistance potential

“…In general, phylogroup G strains are uncommon. However, STc117 is the most prevalent phylogroup G lineage and is commonly isolated from poultry and poultry meat products in Northern Europe (Ronco et al, 2017) and Canada (Bergeron et al, 2012). Recently, it has been shown in the East of England that ST117 represents 8% and 20% of livestock (poultry and pigs) and poultry meat E. coli isolates respectively (Ludden et al, 2019).…”

Effect of ceftiofur cessation and substitution with lincomycin-spectinomycin on extended-spectrum-beta-lactamase/AmpC genes and multidrug resistance in E. coli from a Canadian broiler production pyramid

“…In fact, the results of our study are similar to those obtained in Denmark, where the parent flocks which did not receive ceftiofur but for which the grandparent flocks received cephalosporins (19), demonstrated a 93% prevalence of cephalosporin resistant E. coli (most of the samples being positive for bla CMY-2 ). Vertical transmission of APEC from breeders to their progeny is well known (2) and has been demonstrated recently in the Nordic countries where APEC ST117 O78:H4 was transmitted from grand-parent flocks to their broilers in different countries (31). In addition, Nilsson et al demonstrated the vertical transmission of E. coli carrying bla CMY-2 from grand-parent flocks which had been exposed to ceftiofur to parent and broiler flocks which had never received ceftiofur (29).…”

Genomic analysis of Escherichia coli strains isolated from diseased chicken in the Czech Republic

“…Two isolates were assigned to ST117 (phylogenetic group F). Recent studies indicate that this sequence type comprises important APEC lineages that are repeatedly reported from colibacillosis outbreaks in different countries (25,37,(40)(41)(42), but are also highlighted as potential zoonotic pathogens for containing ExPEC-related virulence genes and being isolated from both retail poultry meat and human clinical urinary tract infections (43). The remaining phylogroup F isolate was ST354, another potentially zoonotic ST, reported particularly from human and animal healthcare facilities and characterized by common resistance to antimicrobials including uoroquinolones (44,45).…”