An investigation into the genetic background of Escherichia coli lineages containing multi-drug resistant clones

Cummins, Elizabeth ORCID: 0000-0003-0575-3151 (2024). An investigation into the genetic background of Escherichia coli lineages containing multi-drug resistant clones. University of Birmingham. Ph.D.

Preview

Cummins2024PhD.pdf
Text - Accepted Version
Available under License Creative Commons Attribution Non-commercial.
Download (14MB) | Preview

Abstract

Escherichia coli is a commensal resident of the human gastrointestinal tract that can also cause disease at multiple extra-intestinal body sites. E. coli is globally recognised as a pathogen of concern due to the high prevalence of antimicrobial resistance (AMR) present within the species. However, the prevalence of AMR is not uniform across the enormously diverse E. coli population. Some E. coli lineages remain largely susceptible to antibiotics, whilst others are resistant to many antibiotic classes and are therefore multi-drug resistant (MDR). A wide spectrum of resistance phenotypes have been observed in strains from throughout the E. coli phylogeny, meaning that the ability to acquire and accumulate
resistance determinants is not an exclusively vertically-inherited trait. A simple explanation for the phylogenetic spread of MDR phenotypes could be that the lineages that encounter antibiotics more frequently are more resistant. Yet this is not the case, as multiple longitudinal studies have shown that large, stable proportions of E. coli bloodstream and urinary tract infections are caused by lineages that do not exhibit high levels of resistance. Compounding the problem, MDR E. coli are adept at colonising the gastrointestinal tracts of healthy humans who are not taking antibiotics. Studies of international travellers have documented colonisation with MDR E. coli occurring within days of arriving in AMR endemic areas.

Type of Work:

Thesis (Doctorates > Ph.D.)

Award Type:

Doctorates > Ph.D.

Supervisor(s):