Dr Melinda Ashcroft
Research Fellow, Respiratory Research, Gallipoli Medical Research
Every day, we are surrounded by bacteria living in the soil beneath our feet, the dust in our homes, and the water flowing through our taps. Most are harmless. Some, however, can cause life-changing disease. Among these are nontuberculous mycobacteria (NTM), bacteria that remain unfamiliar to most people. Although exposure to NTM is part of everyday life, we still know surprisingly little about how they cause infection.
Why do some people develop infection while others exposed to the same environment remain healthy? Why do some infections progress to invasive disease while others remain relatively stable? Why do some people experience repeated infections despite many months of treatment? Even within Queensland, we see striking differences in where infections occur and who is most affected. Understanding these differences is one of the biggest challenges in NTM research.
Answering these questions is increasingly important as NTM infections continue to rise in Queensland [1] and around the world [2, 3]. Lung infections caused by NTM are notoriously difficult to treat. Patients often require combinations of several antibiotics for 12 to 18 months, making treatment a long journey involving frequent medical appointments and uncertainty about whether the infection will return. Despite this, treatments can cause significant side effects and are complicated by antibiotic resistance and relatively low cure rates [4]. For many patients, infections lead to progressive lung damage, reduced quality of life and, in some cases, death.
My path into NTM research has been somewhat unconventional. I originally trained in biotechnology before discovering a passion for computational biology and genomics during my postgraduate studies. My research career began in bacterial genomics before moving into the genomic epidemiology of important antibiotic-resistant pathogens. In 2024, I joined Professor Rachel Thomson and the NTM Australia Research Group at The University of Queensland [5] and Gallipoli Medical Research, where I now investigate NTM infections by combining clinical, environmental and genomic data to answer questions that couldn’t previously be addressed.
Our integrated research approach allows us to investigate NTM infections at multiple levels from population-level patterns to the factors influencing individual patients. We investigate how infections are changing across Queensland, how weather and climate may influence risk, why patients experience different clinical outcomes, and whether bacteria recovered from patients can be linked to those found in their household environments.
For me, that integration is what makes this research so exciting. Rather than studying each piece of the puzzle separately, we can begin connecting the patient, their environment and the bacteria itself. Each provides part of the story, but together they have the potential to answer questions that remain unsolved.
Ultimately, our goal is simple. We want to understand where people acquire these infections, why they only affect some people, and how we can improve outcomes for patients. The knowledge generated through this research will help guide more personalised clinical care, identify opportunities for prevention, and support public health strategies that reduce the future burden of NTM infections in Queensland and beyond.
