Researchers from Singapore General Hospital (SGH), A*STAR’s Genome Institute of Singapore (GIS), and the Yong Loo Lin School of Medicine at the National University of Singapore (NUS Medicine) have identified a new clade of Candida auris, increasing the total number of known clades globally to six.
Candida auris Overview
Candida auris, often referred to as C. auris, is a highly transmissible and challenging-to-eradicate fungus. It primarily affects patients with severe underlying medical conditions, especially those with invasive medical devices like breathing tubes, feeding tubes, and catheters. The fungus can cause a range of infections, from superficial to severe and life-threatening.
Public Health Concerns
In 2022, the World Health Organization designated C. auris as a critical priority for research and public health action. The U.S. Centers for Disease Control and Prevention (CDC) has also classified it as an ‘urgent antimicrobial resistance threat’ due to its increasing treatment difficulty. This underscores the need for enhanced understanding and mitigation strategies.
Discovery Details
The new C. auris clade was identified in 2023 after a patient at SGH tested positive. Although the patient had not traveled abroad and had been in Singapore for two years, this prompted further investigation. Using a machine-learning technique developed by A*STAR’s GIS, researchers tracked the new clade by reconstructing and characterizing C. auris genomes. This led to the confirmation of the new clade.
The discovery was documented in the study titled “Detection and characterization of a sixth Candida auris clade in Singapore: a genomic and phenotypic study,” published in The Lancet Microbe in July 2024. The team found that the patient’s C. auris clade was genetically distinct from the previously known five clades and identified two additional cases in the hospital’s archive.
Surveillance and Future Directions
SGH has an active surveillance program that screens high-risk patients for C. auris upon admission. Positive cases are isolated, and all patients in the same ward or room are screened to contain the spread. The team is now developing a proof-of-concept machine learning approach to automatically detect new clades early. This is crucial for regional hubs like Singapore, which has a high volume of international visitors.
Dr. Chayaporn Suphavilai, Senior Scientist at ASTAR’s GIS, emphasized that the machine learning approach improves surveillance by detecting unusual outlier genomes. This continuous learning process can enhance the detection of potential novel genomes early. Dr. Niranjan Nagarajan, Senior Group Leader at ASTAR’s GIS and Associate Professor at NUS Medicine, highlighted that integrating genomics and collaborative research is vital for pandemic preparedness and response to emerging public health threats.
Multiple Choice Questions (MCQs):
- What is the total number of known clades of Candida auris as of the new discovery?
- A) Five
- B) Six
- C) Seven
- D) Eight
- Which organization listed Candida auris as a critical priority for research in 2022?
- A) U.S. Centers for Disease Control and Prevention (CDC)
- B) World Health Organization (WHO)
- C) National Institutes of Health (NIH)
- D) European Centre for Disease Prevention and Control (ECDC)
- What is the primary method used by the researchers to detect the new Candida auris clade?
- A) Traditional microscopy
- B) Machine learning technique
- C) Chemical assays
- D) X-ray imaging
- In which journal was the study on the new Candida auris clade published?
- A) The Lancet
- B) The Lancet Microbe
- C) Nature Microbiology
- D) Journal of Infectious Diseases
- What is the focus of SGH’s active surveillance program for Candida auris?
- A) Screening all outpatients
- B) Screening high-risk patients upon admission
- C) Testing wastewater
- D) Conducting annual hospital-wide surveys