While Dr Emma Roycroft may describe TB research as “niche,” it is also clearly a vital field when it comes to disease surveillance, both nationally and indeed globally. Roycroft is a Specialist Medical Scientist at St James’s Irish Mycobacteria Reference Laboratory (IMRL). She has been working in St James’s Hospital since 2002. Discussing her research with the Office of the Dean of Research, she highlighted how innovations in genotyping have helped progress the area while stressing the need for more supports for TB public health initiatives.

Dr. Roycroft graduated with a BSc in Applied Science (Biomedical Science) from DIT Kevin St. (now TUD) and TCD in 2002. Following this, she joined the Department of Clinical Microbiology in St James’s. After a few years of being in the routine diagnostic microbiology laboratory, she moved to the IMRL and has been there ever since in various roles. During her time there she has completed a taught Masters in Biomedical Science (UCC) focusing on the molecular epidemiology of Varicella zoster virus. She remained interested in TB and two years later she started genotyping the TB strains that were found in Ireland. “Most TB strains isolated nationally are sent to us in the reference lab,” she explains, “so we have a broad view of the molecular epidemiology of TB in Ireland.” This work enabled her to work closely with the Clinical Microbiology department of the School of Medicine (TCD) who have their offices on the same floor.

It was at this point that her PI at the time, Prof. Tom Rogers, was interested in supporting a researcher from the laboratory to conduct research on TB. Roycroft went for a PhD interview and was successful, so she began a part-time programme alongside her own work. Her PhD, ‘Molecular epidemiology, cluster analysis, and drug resistance prediction of mycobacterium tuberculosis complex in Ireland using conventional methods and whole genome sequencing’, was published in 2017.

Most of us might have a vague awareness of TB as an illness, but what exactly is this disease Roycroft monitors? Currently, 10 million people get TB each year. It kills more people than HIV, and it used to be the top infectious killer until the arrival of COVID-19. The W.H.O. has recently taken it on as a high priority. Each country has its own issues with TB, and there are high- and low-burden countries. Ireland is considered low burden, at 6.9 cases per 100,000 crude prevalence rate. TB clusters tend to be linked to lower socio-economic conditions like homelessness and substance abuse. Even though TB may be decreasing, it remains a public health threat.

Along with her PI, Dr. Margaret Fitzgibbon, and the IMRL team, she also identifies and analyses the susceptibilities of over 200 species of non-tuberculosis mycobacteria (or NTMs) that can cause infections in humans. These are usually opportunistic and are soil- or water-based, and can be pathogenic especially in immunocompromised patients with HIV or cystic fibrosis. Many are newly emerging: “So even though TB might be decreasing” she observes, “we still have the NTMs to keep us busy!”

TB, moreover, “doesn’t recognise borders.” As Irish society is a global one, we have a “heterogenous population with a heterogenous population of TB to match that.” There are laboratory networks across the EU: the IMRL is part of the larger European Reference Laboratory Network for TB (ERLN-TB). TB may not go away entirely for various reasons, however. People on immunosuppressive drugs for chronic illnesses like Crohn’s disease can have latent TB, where they are introduced to the infection but may not develop an active case until later in their lives. This means there’s a “constant reservoir of infection.” Travellers from around the world can also bring drug-resistant strains with them: however, this doesn’t seem to have been a cause of onward transmission in Ireland to date.

Much of Roycroft’s work on TB, she notes, has been based on her PhD research. “Translational research aims to bring the research and development from the research lab to the diagnostic lab, benefiting the patient, and we are very proud that we have managed to introduce this cutting-edge technology for outbreak investigation and drug resistance prediction to the IMRL and TB patients nationwide.” Using genome sequencing they’re attempting to speed up the process to ensure patients are on the right regimen and can be treated faster.

She has just had an abstract accepted for an oral presentation at the Union World Conference on Lung Health 2023, entitled ‘Molecular Epidemiology of Mycobacterium tuberculosis Complex in Ireland over a 10-year Period with a Focus on Whole Genome Sequencing of Informative Clusters.’ This work was a collaboration with the Health Protection Surveillance Centre. They are looking at TB outbreaks and the common themes that might be found within them. These collaborations between multi-disciplinary groups and various stakeholders is particularly interesting, Roycroft enthuses, because of the results: “it’s not just science for its own sake, we’re doing it for a reason.”

Indeed, her working schedule is very hands-on. The IMRL regularly meets with a multi-disciplinary team which includes Prof. Joseph Keane and Dr Annemarie McLaughlin, the respiratory consultants in St James’s, TB Clinical Nurse Specialist Lorraine Dolan, and SJH Microbiology medics. There are also often colleagues from pharmacy, public health, radiology and the infectious disease team, as well as experts from other hospitals: “They might get in contact with us, as they can ask questions on difficult cases in that forum.” She often collaborates with Prof. Keane, who has his own team of immunology-based TB research going on in TTMI (Trinity Translational Medicine Institute), so Roycroft’s team “feed into that every now and then.” One major collaboration between the IMRL, the above group, and the Irish Prison Service led to the publication of ‘The largest prison outbreak of TB in Western Europe investigated using whole-genome sequencing’, published in 2021.

Unsurprisingly, Roycroft would highly recommend anyone to study microbiology. As for TB research, “it’s a niche research area but it’s got worldwide appeal. TB is huge, it’s got impact. And what you’re doing has impact on the patient. And that’s big in terms of job satisfaction.”