Retrospective Analysis of Bacterial Cultures Sampled in German Chicken-Fattening Farms During the Years 2011–2012 Revealed Additional VIM-1 Carbapenemase-Producing Escherichia coli and a Serologically Rough Salmonella enterica Serovar Infantis

Abstract

Carbapenems are last-resort antibiotics used in human medicine. The increased detection of carbapenem-resistant Enterobacteriaceae (CRE) is therefore worrying. In 2011 we reported the first livestock-associated VIM-1-producing Salmonella (S.) enterica serovar Infantis (R3) isolate from dust, sampled in a German chicken fattening farm. Due to this observation we retrospectively investigated more than 536 stored bacterial cultures, isolated from 45 chicken fattening farms during the years 2011 and 2012. After a non-selective overnight incubation, the bacteria were transferred to selective media. Escherichia (E.) coli and Salmonella growing on these media were further investigated, including antibiotic susceptibility testing, carbapenemase gene screening and whole genome sequencing (WGS). In total, four CRE were found in three out of 45 investigated farms: Besides R3, one additional Salmonella (G-336-1a) as well as two E. coli isolates (G-336-2, G-268-2). All but G-268-2 harbored the blaVIM-1 gene. Salmonella isolates R3 and G-336-1 were closely related although derived from two different farms. All three blaVIM-1-encoding isolates possessed identical plasmids and the blaVIM-1- containing transposon showed mobility at least in vitro. In isolate G-268-2, the AmpC beta-lactamase gene blaCMY-2 but no known carbapenemase gene was identified. However, a transfer of the phenotypic resistance was possible. Furthermore, G-268-2 contained the mcr-1 gene, combining phenotypical carbapenem- as well as colistin resistance in one isolate. Carbapenem-resistant Enterobacteriaceae have been found in three out of 45 investigated chicken flocks. This finding is alarming and emphasizes the importance of intervention strategies to contain the environmental spread of resistant bacteria in animals and humans.

Phylogenetically Diverse Escherichia Coli Strains From Chicken Co-Harbour Multiple Carbapenemase Encoding Genes (blaNDM-blaOXA-blaIMP)

“…The presence of carbapenem resistance in bacteria from animals, including food-producing animals (pigs, bovines and horses) has also been reported from some European countries such as Germany, France and Belgium [9]. The identification of E.coli isolates harbouring multiple (at least two) carbapenemase encoding genes from food animal in this study differentiates it from previous similar studies which mostly reported E. coli isolates harbouring one or two carbapenemase genes [11,12].…”

ChromID® CARBA Agar Fails to Detect Carbapenem-Resistant Enterobacteriaceae With Slightly Reduced Susceptibility to Carbapenems

“…Aside from clinical settings, the carbapenemase enzymes OXA, VIM, NDM, and KPC possess the highest impact in wildlife, pets, and the food chain ( Grundmann et al, 2017 ; Köck et al, 2018 ). In Germany, France, Italy, Spain, and the Netherlands, reports have been published about carbapenem-resistant Enterobacteriaceae (CRE) in companion animals (i.e., dogs, cats, horses) ( Stolle et al, 2013 ; Schmiedel et al, 2014 ; Gonzalez-Torralba et al, 2016 ; Melo et al, 2017 ; Vittecoq et al, 2017 ; Pulss et al, 2018 ), seafood (i.e., shrimps, blue mussels, cockles) ( Roschanski et al, 2016 ; Ceccarelli et al, 2017 ), wild animals (i.e., yellow-legged gulls, black kite) ( Fischer et al, 2013b ; Vergara et al, 2017 ; Vittecoq et al, 2017 ), and food of livestock animals (i.e., beef, chicken meat, pork) ( Schwaiger et al, 2008 ; Leverstein-van Hall et al, 2011 ; Poirel et al, 2012 ; Zurfluh et al, 2016 ; Ceccarelli et al, 2017 ; Fischer et al, 2017 ; Pulss et al, 2017 ; Randall et al, 2017 ; Roschanski et al, 2017 , 2018 ). In 2011, VIM-1-producing Enterobacteriaceae ( Salmonella Infantis and E. coli ) were found in several chicken and pig farms in Germany ( Borowiak et al, 2017 ; Falgenhauer et al, 2017 ; Fischer et al, 2017 ; Irrgang et al, 2017 , 2019 ; Roschanski et al, 2018 ).…”

Horizontal Gene Transfer and Acquired Antibiotic Resistance in Salmonella enterica Serovar Heidelberg followingIn VitroIncubation in Broiler Ceca

“…2A), suggesting a plasmid with ϳ2 copies per chromosome. Recently, Roschanski et al showed that an E. coli isolate carrying an IncB/O/K/Z-like plasmid bearing a bla CMY-2 gene conferred resistance to cephalosporins and carbapenems, and they hypothesized that overexpression of CMY-2 and high plasmid copy numbers (PCNs) (8 per cell) were responsible for decreased susceptibility to carbapenems (21). In our study, this isolate exhibited increased resistance to multiple cephalosporin and penicillin drugs but was susceptible to the carbapenems tested (Table 2), indicative of an extended-spectrum-␤-lactamase (ESBL)-like-producing S. Heidelberg strain.…”