Dr Catherine Ludden


Research Fellow

Keppel Street
United Kingdom

Catherine Ludden obtained a BSc in Medical Science from the Galway-Mayo Institute of Technology. In 2010, Catherine decided to further investigate the genetic diversity, transmission and evolution of antimicrobial resistant bacteria in nursing homes and hospitals during her PhD at the National University of Ireland Galway. Having completed her PhD, Catherine moved to the University of Cambridge to take up a Postdoctoral Research Associate position in Professor Sharon Peacock's group at the Department of Medicine. In April 2016, she joined the Department of Infectious and Tropical Diseases as a Sir Henry Postdoctoral Wellcome Fellow. Her research is based on a One Health approach to investigate the origin and transmission of antimicrobial-resistant E. coli in the UK. This involves the use of whole-genome sequencing to determine the genetic relatedness of isolates and associated mobile genetic elements from different sources to define shared reservoirs. She is also working on integrating whole genome sequencing into health services for the surveillance of Carbapenem resistant Enterobacteriaceae in Ireland. In 2019, Catherine joined the European Centre for Disease Prevention and Control (ECDC) to provide expertise in Antimicrobial Resistance and Healthcare Associated Infections. During her time at ECDC, she was responsible for providing scientific advice and helped with the development of surveillance systems and analysis of whole genome data. Currenly, Catherine is part of the COVID-19 UK (COG-UK) Consortium which is supporting national genomic for surveillance of COVID-19 by delivering large scale, rapid sequencing of COVID-19 samples. As part of the COG-UK Consortium, Catherine is an Operations Coordinator and is responsible for enrolling sample sites to the consortium, coordinating the receipt and processing of samples, assisting with developing sampling strategies and the generation of reports. Catherine is also a Trustee of the Society for Applied Microbiology and an International Ambassador for the Society for Healthcare Epidemiology of America.


Department of Clinical Research
Department of Infection Biology


Centre for the Mathematical Modelling of Infectious Diseases (CMMID)
Antimicrobial Resistance Centre (AMR)


Teaching the module for Practical Procedures in Clinical Microbiology to medical students, including laboratory supervision, practical demonstration, project design, laboratory report corrections and tutorials.

Teaching the topic of "One Health" on the short course entitled Antimicrobial Resistance (AMR): a Multidisciplinary Approach.


The bacterium Escherichia coliis a major cause of infections in people in hospitals and the community. E. coli can become resistant to commonly used antibiotics through the acquisition of resistance-encoding genes. When people are infected with these strains, their infection can be difficult to treat and they are at a higher risk of death. 

Catherine Ludden's research is based on a One Health approach to investigate the origin and transmission of antimicrobial-resistant E. coli in the UK.She will use genome sequence data of antimicrobial-resistant E. coli from hospitalised haematology patients, the hospital environment, livestock, wastewater and bloodstream infections in the UK to determine the genetic relatedness of isolates and associated mobile genetic elements from these different sources to define shared reservoirs. Mathematical modelling will be used to infer transmission, test hypotheses and to determine the likely impact of interventions to reduce transmission of antimicrobial-resistant E. coli.

She is also involved in the development a National Surveillance programme for Carbapenem resistant Enterobacteriaceae in Ireland and integrating whole genome sequencing into health services. This will provide evidence on antimicrobial resistance reservoirs, routes of transmission between them and detection of novel mechanisms of resistance in emerging strains.

Research Area
Drug resistance
Health care policy
Public health
Disease control
Environmental Health
Global Health
Genetic epidemiology
Molecular epidemiology
Mathematical modelling
Molecular biology
Disease and Health Conditions
Emerging Infectious Disease
Hospital acquired infection

Selected Publications

One Health Genomic Surveillance of Escherichia coli Demonstrates Distinct Lineages and Mobile Genetic Elements in Isolates from Humans versus Livestock.
Ludden C; Raven KE; Jamrozy D; Gouliouris T; Blane B; Coll F; de Goffau M; Naydenova P; Horner C; Hernandez-Garcia J
Genomic Surveillance of Enterococcus faecium Reveals Limited Sharing of Strains and Resistance Genes between Livestock and Humans in the United Kingdom.
Gouliouris T; Raven KE; Ludden C; Blane B; Corander J; Horner CS; Hernandez-Garcia J; Wood P; Hadjirin NF; Radakovic M
Sharing of carbapenemase-encoding plasmids between Enterobacteriaceae in UK sewage uncovered by MinION sequencing.
Ludden C; Reuter S; Judge K; Gouliouris T; Blane B; Coll F; Naydenova P; Hunt M; Tracey A; Hopkins KL
Microbial genomics
Within-host evolution of Enterococcus faecium during longitudinal carriage and transition to bloodstream infection in immunocompromised patients.
Moradigaravand D; Gouliouris T; Blane B; Naydenova P; Ludden C; Crawley C; Brown NM; Török ME; Parkhill J; Peacock SJ
Genome medicine
Transmission of methicillin-resistant Staphylococcus aureus in long-term care facilities and their related healthcare networks.
Harrison EM; Ludden C; Brodrick HJ; Blane B; Brennan G; Morris D; Coll F; Reuter S; Brown NM; Holmes MA
Genome medicine
See more Publications