A high prevalence of bla OXA-48 in Klebsiella (Raoultella) ornithinolytica and related species in hospital wastewater in South West England

Abstract

Klebsiella species occupy a wide range of environmental and animal niches, and occasionally cause opportunistic infections that are resistant to multiple antibiotics. In particular, Klebsiella pneumoniae (Kpne) has gained notoriety as a major nosocomial pathogen, due principally to the rise in non-susceptibility to carbapenems and other beta-lactam antibiotics. Whilst it has been proposed that the urban water cycle facilitates transmission of pathogens between clinical settings and the environment, the level of risk posed by resistant Klebsiella strains in hospital wastewater remains unclear. We used whole genome sequencing (WGS) to compare Klebsiella species in contemporaneous samples of wastewater from an English hospital and influent to the associated wastewater treatment plant (WWTP). As we aimed to characterize representative samples of Klebsiella communities, we did not actively select for antibiotic resistance (other than for ampicillin), nor for specific Klebsiella species. Two species, Kpne and K. ( Raoultella ) ornithinolytica (Korn), were of equal dominance in the hospital wastewater, and four other Klebsiella species were present in low abundance in this sample. In contrast, despite being the species most closely associated with healthcare settings, Kpne was the dominant species within the WWTP influent. In total, 29 % of all isolates harboured the bla OXA-48 gene on a pOXA-48-like plasmid, and these isolates were almost exclusively recovered from the hospital wastewater. This gene was far more common in Korn (68 % of isolates) than in Kpne (3.4 % of isolates). In general plasmid-borne, but not chromosomal, resistance genes were significantly enriched in the hospital wastewater sample. These data implicate hospital wastewater as an important reservoir for antibiotic-resistant Klebsiella , and point to an unsuspected role of species within the Raoultella group in the maintenance and dissemination of plasmid-borne bla OXA-48. This article contains data hosted by Microreact.

A large-scale genomic snapshot of Klebsiella spp. isolates in Northern Italy reveals limited transmission between clinical and non-clinical settings

“…A single isolate recovered from the surface of an automated teller machine (ATM) was assigned as a new species belonging to the genus Superficiebacter, designated Superficiebacter maynardsmithii 29 , and was retained as a convenient outgroup. Previous WGS studies did not support the assignment of the Raoultella species as a separate genus 7,23,30 , which is consistent with our data. Hence, we refer to these species as Klebsiella.…”

“…6 Boyd Orr Centre for Population and Ecosystem Health, School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK. 7 Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK. 8 Microbiology and Virology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy.…”

“…Antibiotic resistance has spread rapidly within K. pneumoniae and other members of the genus since the early 1980s 2 ; the plasmid-mediated spread of genes encoding carbapenemases over the last two decades is of particular concern 3,4 . Widespread clones of K. pneumoniae and other Klebsiella species associated with these genes are spread through the healthcare network 5 ; in common with other key antimicrobial resistance (AMR) determinants, genes encoding carbapenemases have also been detected in multiple non-clinical settings including livestock and wastewater [6][7][8] .…”

One Health or Three? Transmission modelling ofKlebsiellaisolates reveals ecological barriers to transmission between humans, animals and the environment

“…K. pneumoniae (K. pne) is by far the most commonly sampled species, accounting for approximately half of the isolates (n=1705). Previous studies based on WGS data do not support the assignment of the Raoultella species as a separate genus 7,26,41 , and this is further supported by our data. Hence in this work we have referred to these species as Klebsiella.…”

“…Widespread clones of K. pneumoniae and other Klebsiella species that are associated with these genes are primarily spread through the health-care network 5 . In addition, and in common with other key AMR determinants, genes encoding carbapenemases have been reported in multiple non-clinical settings including livestock and wastewater [6][7][8] .…”