Abeni Beshiru (Berlin / DE; Oghara / NG), Etinosa O Igbinosa (Berlin / DE; Benin City / NG), Sascha Al Dahouk (Berlin / DE), Ralf Dieckmann (Berlin / DE), Szilvia Neuhaus (Berlin / DE)
Background
Slaughterhouses are known reservoirs for pathogenic bacteria, and elicit food safety apprehensions. Klebsiella species, recognized opportunistic pathogens, may occur on meat surfaces and require a thorough understanding of their slaughterhouse characteristics for accurate assessment of associated transmission and human health risks. This study investigated phenotypic and genomic features of Klebsiella isolates, shedding light on antimicrobial resistance (AMR) and potential virulence factors, offering valuable insights for public health considerations.
Methodology
Before and after disinfection, surface samples from slaughterhouse underwent Klebsiella species isolation and identification via MALDI-TOF. Antimicrobial and biocide susceptibilities were ascertained for relevant substances, evaluating both minimum inhibitory concentration (MIC) and additionally minimum bactericidal concentration for biocides. Isolates with high biocide MICs were subjected to efflux pump inhibition testing. Further, Klebsiella underwent screening for biofilm formation capabilities. Whole genome sequencing (WGS) was employed to explore genetic diversity and potential traits contributing to persistence.
Results
The majority of recovered isolates was identified as K. pneumoniae (n=105). Additional species included K. aerogenes (n=6), K. quasipneumoniae (n=7), and K. variicola (n=13). Biocide susceptibility varied, with two isolates showing triclosan resistance compared to in-use concentrations. Efflux pump inhibition resulted in increased susceptibility to octenidine dihydrochloride and didecyldimethylammonium chloride. Out of the total isolates, 31 K. pneumoniae (23.7%) exhibited multidrug resistance. Two K. pneumoniae isolates were extended-spectrum β-lactamase producers. Biofilm formation was prevalent, with stronger biofilm forming ability post-disinfection. WGS revealed a broad genetic diversity, encompassing AMR, virulence, biocide, and biofilm genes.
Conclusions
Our findings highlight various public health relevant characteristics of Klebsiella isolates from slaughterhouses, emphasizing diverse AMR profiles and genetic traits.