What WGS Reveals about Salmonella enterica subsp. enterica in Wildlife in Germany

Abstract

The aim of this study was to gain an overview of the genetic diversity of Salmonella found in wildlife in Germany. We were particularly interested in exploring whether wildlife acts as a reservoir of certain serovars/subtypes or antimicrobial resistance (AMR) genes. Moreover, we wanted to explore the potential of Salmonella in spreading from wildlife to livestock and humans. To answer these questions, we sequenced 260 Salmonella enterica subsp. enterica isolates sampled between 2002 and 2020 from wildlife across Germany, using short-read whole genome sequencing. We found, consistent with previous findings, that some Salmonella sequence types are associated with certain animal species, such as S. Choleraesuis ST145 with wild boar and S. Enteritidis ST183 with hedgehogs. Antibiotic resistance was detected in 14.2% of all isolates, with resistance against important WATCH group antibiotics present in a small number of isolates. We further found that wildlife isolates do not form separate phylogenetic clusters distant to isolates from domestic animals and foodstuff, thus indicating frequent transmission events between these reservoirs. Overall, our study shows that Salmonella in German wildlife are diverse, with a low AMR burden and close links to Salmonella populations of farm and food-production environments.

Rural Raccoons (Procyon lotor) Not Likely to Be a Major Driver of Antimicrobial Resistant Human Salmonella Cases in Southern Ontario, Canada: A One Health Epidemiological Assessment Using Whole-Genome Sequence Data

“…Our course-grained epidemiological investigation of Salmonella from various sources in southern Ontario has provided insights into potential transmission between these different sources, and provides further evidence that, although raccoons have the potential to disseminate Salmonella and AMR to humans, their contribution appears to be minimal. Our findings build on existing work suggesting that wildlife play a largely indirect role in the transmission of Salmonella, serving primarily as biological intermediaries between humans, livestock and the environment, rather than acting as a primary driver or major reservoir (40)(41)(42)(43)(44). The identification of highly similar or identical cgMLST types (<10 allelic differences) was a rare occurrence in this population of over 600 isolates and was very specific to certain sources and serovars, highlighting potential transmission only in certain contexts (i.e., S. Heidelberg between poultry and humans, S. Newport between raccoons and soil).…”

Antibiofilm Activity and Synergistic Effects of Thymol-Loaded Poly (Lactic-Co-Glycolic Acid) Nanoparticles with Amikacin against Four Salmonella enterica Serovars

“…Salmonella is a genus of the family Enterobacteriaceae. Taxonomically, this genus is separated into two species: Salmonella bongori and Salmonella enterica, which contain six subspecies with serovars like Salmonella Typhi, Salmonella Enteritidis, Salmonella Paratyphi, Salmonella Typhimurium, and Salmonella Choleraesuis [1].Salmonella enterica causes typhoidal and nontyphoidal salmonellosis (NTS) [2]. Te WHO estimates the global typhoid fever disease burden at 11-20 million cases annually, resulting in about 128 000-161 000 deaths per year [3].…”

Zoonotic bacterial and parasitic intestinal pathogens in foxes, raccoons and other predators from eastern Germany

“…While we isolated Y. enterocolitica from 12 out of 77 samples, only one strain isolated from a raccoon harboured the known virulence plasmid and can thus be considered pathogenic. Salmonella Choleraesuis ST‐145 is mainly found in wild boar but has also been reported in foxes in Germany by Uelze et al ( 2021 ). Interestingly, Uelze et al also reported that aminoglycoside resistance genes and ciprofloxacin resistance conferring mutations, which were however, different from the gene and mutation detected in our strain.…”

“…Other pathogens such as Salmonella enterica subsp. enterica (Uelze et al, 2021 ), Yersinia enterocolitica (Carella et al, 2022 ) and Listeria spp. (Nowakiewicz et al, 2016 ) have been reported from predators, but their genomic sequences are largely missing so far, making comparisons to human isolates difficult.…”