Faecal carriage of enterococci harbouring oxazolidinone resistance genes among healthy humans in the community in Switzerland. (16th August 2022)

• Record Type: Journal Article
• Authors: Nüesch-Inderbinen, Magdalena; Biggel, Michael; Zurfluh, Katrin; Treier, Andrea; Stephan, Roger
• Is Part Of: Journal of antimicrobial chemotherapy. Volume 77:Number 10(2022)
• Page Start: 2779
• Page End: 2783
• Publication Date: 2022-08-16
• Subjects: Anti-infective agents -- Periodicals; Chemotherapy -- Periodicals; 615.58
• DOI: 10.1093/jac/dkac260
• Languages: English
• ISSNs: 0305-7453

Abstract

Abstract: Objectives: This study aimed to investigate the faecal carriage of enterococci harbouring oxazolidinone resistance genes among healthy humans in Switzerland and to genetically characterize the isolates. Methods: A total of 399 stool samples from healthy individuals employed in different food-processing plants were cultured on a selective medium containing 10 mg/L florfenicol. Resulting enterococci were screened by PCR for the presence of cfr, optrA and poxtA . A hybrid approach combining short-read and long-read WGS was used to analyse the genetic context of the cfr, optrA and poxtA genes. Results: Enterococcus faecalis ( n = 6), Enterococcus faecium ( n = 6), Enterococcus gallinarum ( n = 1) and Enterococcus hirae ( n = 2) were detected in 15/399 (3.8%) of the faecal samples. They carried cfr + poxtA, optrA, optrA + poxtA or poxtA . Four E. faecalis harbouring optrA and one E. faecium carrying poxtA were resistant to linezolid (8 mg/L). In most optrA -positive isolates, the genetic environments of optrA were highly variable, but often resembled previously described platforms. In most poxtA -positive isolates, the poxtA gene was flanked on both sides by IS 1216E elements and located on medium-sized plasmids. Conclusions: Faecal carriage of Enterococcus spp. harbouring cfr, optrA and poxtA in healthy humans associated with the food-production industry demonstrates the possibility of spread of oxazolidinone resistance genes into the community. Given the importance of linezolid as a last-resort antibiotic for the treatment of serious infections caused by Gram-positive pathogens, the detection of the oxazolidinone resistance determinants in enterococci from healthy humans is of concern for public health.