Genetic & virulence profiling of ESBL-positive E. coli from nosocomial & veterinary sources

Abstract

CTX-M genes are the most prevalent ESBL globally, infiltrating nosocomial, community and environmental settings. Wild and domesticated animals may act as effective vectors for the dissemination of CTX-producing Enterobacteriaceae. This study aimed to contextualise blaCTX-M-14-positive, cephalosporin-resistant Enterobacteriaceae human infections and compared resistance and pathogenicity markers with veterinary isolates. Epidemiologically related human (n=18) and veterinary (n=4) blaCTX-M-14-positive E. coli were fully characterised. All were typed by XbaI pulsed field gel electrophoresis and ST. Chromosomal/plasmidic locations of blaCTX-M-14 were deduced by S1-nuclease digestion, and association with ISEcp1 was investigated by sequencing. Conjugation experiments assessed transmissibility of plasmids carrying blaCTX-M-14. Presence of virulence determinants was screened by PCR assay and pathogenicity potential was determined by in vitro Galleria mellonella infection models. 84% of clinical E. coli originated from community patients. blaCTX-M-14 was found ubiquitously downstream of ISEcp1 upon conjugative plasmids (25-150 kb). blaCTX-M-14 was also found upon the chromosome of eight E. coli isolates. CTX-M-14-producing E. coli were found at multiple hospital sites. Clonal commonality between patient, hospitals and livestock microbial populations was found. In vivo model survival rates from clinical isolates (30%) and veterinary isolates (0%) were significantly different (p<0.05). Co-transfer of blaCTX-M-14 and virulence determinants was demonstrated. There is evidence of clonal spread of blaCTX-M-14-positive E. coli involving community patients and farm livestock. blaCTX-M-14 positive human clinical isolates carry a lower intrinsic pathogenic potential than veterinary E. coli highlighting the need for greater veterinary practices in preventing dissemination of MDR E. coli among livestock.

CTX-M ESBL-producing Enterobacteriaceae: estimated prevalence in adults in England in 2014

“… 37 In our study, carriers of bla CTX-M-27 were mainly from the Asian-IPB ethnic group (59%), whereas carriers of bla CTX-M-14 were mainly from the white ethnic group (83%); this variation by ethnicity warrants further investigation. In a Spanish study 38 , CTX-M-14-producing E. coli were mainly isolated from community UTIs; this was also found in a Welsh study, where 83% of the CTX-M-14 genotype were community acquired 39 and they were more common in rural areas. 40 CTX-M-14 E. coli may be indigenous in the UK community, possibly acquired from cattle.…”

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in cattle production – a threat around the world

“…Infection (Hunter et al, 2010) Turkey Faecal (AslantaŞ et al, 2017;Pehlivanoglu et al, 2016) Asia China Faecal (Zheng et al, 2019) Mastitis (Ali et al, 2016(Ali et al, , 2017 South Korea Mastitis (Tark et al, 2017) Hong (Eisenberger et al, 2017;Freitag et al, 2017;Michael et al, 2017) Sick (Michael et al, 2017) Belgium Faecal (Pardon et al, 2017) Infection (Pardon et al, 2017) France Faecal (Haenni et al, 2014;Madec et al, 2008) Mastitis (Dahmen et al, 2013) Sick (Madec et al, 2008) Wales Sick (Tyrrell et al, 2016) Netherlands Faecal (Ceccarelli et al, 2019;Heuvelink et al, 2019;Hordijk et al, 2013a, b, c) United Kingdom Faecal (Cottell et al, 2011;Horton et al, 2011;Randall et al, 2014;Snow et al, 2011) Infection (Hunter et al, 2010) ND (Stokes, 2014;Stokes et al, 2013) Switzerland Faecal (Geser et al, 2012a;Zurfluh et al, 2015) Mastitis (Geser et al, 2012a) Asia China Faecal (Zheng et al, 2012(Zheng et al, , 2019 Mastitis (Ali et al, 2016(Ali et al, , 2017 South Korea Faecal (Rayamajhi et al, 2011;Tamang et al, 2013a) Sick (Lim et al, 2009) Hong Kong Faecal Japan Mastitis (Ohnishi et al, 2013b) Diarrheic (Ohnishi et al,...…”

Whole genome sequences of multi-drug resistant Escherichia coli isolated in a Pastoralist Community of Western Uganda: Phylogenomic changes, virulence and resistant genes

“…A high variation of virulence genes was registered among the E. coli genome from humans than those of cattle origin further supports the hypothesis that the E. coli isolated from the two hosts have a common ancestral origin. However, some studies have found clonal commonality between E.coli isolated from the hospital, the community and animals [36]. The reason for this discrepancy is mainly due to the different methods used.…”