Colistin-resistant Enterobacterales among veterinary healthcare workers and in the Dutch population

Abstract

Objectives Plasmid-mediated colistin resistance can be transferred from animals to humans. We investigated the prevalence of carriage of mcr-mediated colistin-resistant Escherichia coli and Klebsiella pneumoniae (ColR-E/K) in veterinary healthcare workers and in the general population in the Netherlands. Methods Two cross-sectional population studies were performed: one among veterinary healthcare workers and one in the general population. Participants sent in a faecal sample and filled in a questionnaire. Samples were analysed using selective enrichment and culture. Mobile colistin resistance genes (mcr) were detected by PCR and ColR-E/K were sequenced using Illumina and Nanopore technologies. Results The prevalence of mcr-mediated ColR-E/K was 0.2% (1/482, 95% CI 0.04%–1.17%) among veterinary personnel and 0.8% (5/660, 95% CI 0.3%–1.8%) in the population sample. mcr-1 was found in E. coli from four persons, mcr-8 in K. pneumoniae from one person and another person carried both mcr-1 and mcr-8 in a K. pneumoniae isolate. mcr-1 was found on different plasmid types (IncX4, IncI1 and IncI2), while mcr-8 was found on IncF plasmids only. Conclusions mcr-mediated ColR-E/K resistance was uncommon in both populations. Professional contact with animals does not increase the chance of carriage of these bacteria in the Netherlands at present. mcr-8 was found for the first time in the Netherlands. Surveillance of colistin resistance and its underlying mechanisms in humans, livestock and food is important in order to identify emerging trends in time.

One Health surveillance of colistin-resistant Enterobacterales in Belgium and the Netherlands between 2017 and 2019

“…Fortunately, inter-host transmission between humans and livestock animals was not observed in this study nor in other studies [61,64,65] and resistance to fluoroquinolones, extended-spectrum cephalosporins, aminoglycosides and carbapenems remained low (<10%), providing several alternative treatment options for these colistin-resistant isolates.…”

“…The persistence of the highly related IncX4 plasmids harboring mcr-1.1 or mcr-2.1 over a one-year period in these pig farms emphasizes the need for increased efforts to control the spread of mcr genes. For example, the ban on free use of colistin in animals has reduced the incidence of mcr-1-harboring IncX4-type plasmids, whose presence is associated with an effective dispersal potential in Enterobacterales and across different One Health niches (human, dogs, chickens and flies) [13][14][15]61]. Co-localization of mcr genes with other resistance genes on the same plasmid was not detected in our study, however, the majority of isolates was sequenced using short-read sequencing which complicates this analysis.…”

Colistin Resistance Mechanisms in Human and Veterinary Klebsiella pneumoniae Isolates

“…The plasmid-borne resistance mechanism mediated by mcr-1 was only detected in one human isolate (KP_2442) [ 16 ]. For this mechanism the opportunity of transfer from companion animals or livestock to humans has been described [ 33 , 34 , 35 ]. However, due to the different mutations in LPS-associated genes as well as the diverse sequence types and high number of SNPs, transmission of COL-resistant strains from animals to humans and vice versa seems to not be the main route of dissemination.…”

Epidemiology and Traits of Mobile Colistin Resistance (mcr) Gene-Bearing Organisms from Horses

“…The administration of COL by untrained individuals potentially results in the development of COL resistance. Veterinary healthcare workers (VHWs) are known to have been colonized by COL-r and MGBB [ 52 ], and the role of the veterinary hospital environment as a reservoir for COL-r organisms is recognized [ 53 ]. Therefore, the nosocomial infection of horses by resistant organisms could occur following visitation to veterinary hospitals through the hands of unhygienic VHWs, horse caretakers, and/or the hospital environment [ 54 ].…”