A deadly, drug-resistant fungus spreading in hospitals may finally be vulnerable. Scientists have uncovered a key genetic process that could be exploited to develop new treatments against the pathogen, which has caused repeated ICU shutdowns. The finding offers new hope for controlling an infection that has long resisted both containment and therapy.

Candida auris is a dangerous pathogen for patients who are already critically ill, leaving hospitals especially susceptible to outbreaks. While the fungus often lives harmlessly on the skin, people who require ventilators are at significantly higher risk of infection. Once established, it is fatal in roughly 45 per cent of cases and resists all major classes of antifungal drugs, making outbreaks notoriously difficult to control and eradicate in hospital settings.

Figure 1. Candida auris Filaments During Infection

A Global Health Threat on the Rise

Candida auris was first identified in 2008, and its origins remain unknown. Since then, outbreaks have been documented in more than 40 countries, including the UK. Also known as Candidozyma auris, the fungus is now classified as a global health threat and is listed on the World Health Organization’s critical priority fungal pathogens list. In the UK, reported cases have continued to rise steadily. Figure 1. Candida auris Filaments During Infection.

Studying Infection Inside a Living Host

Researchers at the University of Exeter have, for the first time, closely tracked how Candida auris switches on its genes during infection, using an innovative fish-larvae model. Published in Communications Biology and supported by Wellcome, the Medical Research Council, and NC3Rs, the study points to a potential biological vulnerability that could be exploited to develop new antifungal therapies or repurpose existing drugs—if the same genetic behavior is confirmed in human infections.

The study was co-led by NIHR Clinical Lecturer Hugh Gifford of the University of Exeter’s MRC Centre for Medical Mycology. He noted that since its emergence, Candida auris has caused severe disruption in hospital intensive care units, proving deadly for vulnerable patients and costly to eliminate. The team believes their findings may have uncovered an Achilles’ heel in the pathogen during active infection, highlighting the urgent need for further research to determine whether this weakness can be effectively targeted by antifungal drugs.

Why a New Model Was Necessary

A major obstacle in studying Candida auris has been its ability to tolerate high temperatures and unusually high salt levels, traits that have led researchers to speculate about origins in tropical oceans or marine animals. These same characteristics have limited the usefulness of traditional laboratory models. To address this, the Exeter team developed a new approach using Arabian killifish, whose eggs can survive at human body temperature, allowing the researchers to observe infection in a living host under realistic conditions.

Genetic Insights Into Survival and Spread

The researchers found that Candida auris can transform into elongated filament-like forms during infection, a change that may help it seek out nutrients within the host. By tracking gene activity in real time, the team identified patterns that point to possible vulnerabilities. Notably, several genes switched on during infection are linked to nutrient transport systems that capture iron-binding molecules and funnel iron into fungal cells. Because iron is vital for survival, this reliance could represent a key weakness.

Co-senior author Dr. Rhys Farrer of the University of Exeter’s MRC Centre for Medical Mycology explained that this is the first time gene activity has been observed during infection in a living host. He noted that determining whether the same genetic behavior occurs in humans will be crucial. The activation of iron-scavenging genes not only hints at the fungus’s possible origins in iron-poor marine environments but also points to promising targets for both new antifungal treatments and the repurposing of existing drugs.

New Hope for Future Treatments

Dr. Gifford, who also serves as a resident physician in intensive care and respiratory medicine at the Royal Devon & Exeter Hospital, highlighted the clinical significance of the findings. He noted that although further research is needed, the discovery offers an encouraging avenue for future treatments [1]. Existing drugs that interfere with iron-scavenging processes already exist, and the next step will be to investigate whether these could be repurposed to prevent Candida auris infections from causing deaths and forcing ICU closures.

The Arabian killifish larvae model was developed with funding from an NC3Rs project grant as an alternative to traditional mouse and zebrafish models, which are commonly used to study host–pathogen interactions.

Dr. Katie Bates, Head of Research Funding at NC3Rs, said the study highlights the value of this replacement model for investigating Candida auris infection, providing unprecedented insight into cellular and molecular processes in living hosts. She described the work as an excellent example of how innovative alternative approaches can overcome major limitations of conventional animal studies.

References:

1. https://scitechdaily.com/deadly-hospital-fungus-may-finally-have-a-weakness/

Cite this article:

Janani R (2025), Researchers Identify Possible Weakness in Deadly Hospital Fungus, AnaTechMaz, pp. 639