Candida auris, a drug-resistant fungus, has been identified in 27 US states, with over 7,000 recorded infections and colonizations in 2025. The organism, which the Centers for Disease Control and Prevention (CDC) classifies as an urgent antimicrobial resistance threat, has also been detected in at least 60 countries globally. Its prevalence and resistance to multiple antifungal medications present challenges for public health, particularly within healthcare settings.
Prevalence and Scope
In 2025, approximately 7,000 cases of C. auris, encompassing both clinical infections where patients exhibit symptoms and colonization cases where the fungus is present without causing illness, were reported across 27 US states. This represents an increase in both case numbers and geographic distribution within the United States compared to previous years. Globally, C. auris, first identified in 2009, has been detected in numerous countries, with reports indicating its presence in at least 60 nations.
Characteristics and Risk Factors
C. auris is a yeast capable of causing invasive infections in the bloodstream, wounds, and ears. It primarily affects critically ill individuals, including those with compromised immune systems, patients in intensive care units, and those using medical devices such as catheters or ventilators. Among infected patients, mortality rates are estimated at approximately 50% in critically ill individuals. The fungus is not considered a significant threat to healthy individuals.
A key characteristic of C. auris is its resistance to multiple classes of antifungal drugs; some strains have demonstrated resistance to all currently available treatments. Its unique cell wall structure contributes to this resistance.
Transmission and Persistence
C. auris can persist on human skin, hospital surfaces, and medical equipment for weeks, which facilitates its transmission within healthcare environments. Transmission has predominantly occurred in healthcare settings, where vulnerable patients are susceptible to exposure. The ability of the fungus to spread easily within these environments and persist on surfaces makes outbreak control difficult. Some outbreaks in US hospitals have led to temporary closures of intensive care units.
Management Challenges and Research Directions
Managing C. auris infections is complex due to several factors:
- Antifungal Resistance: Many strains are resistant to multiple antifungal medications, with only four major classes of antifungal drugs currently available. While three new antifungal drugs have been approved or are in late-stage trials, drug development faces challenges in keeping pace with the fungus's evolution.
- Diagnostic Difficulties: Standard laboratory tests may misidentify C. auris, delaying appropriate treatment and infection control measures.
- Environmental Persistence: The fungus's ability to persist on environmental surfaces for extended periods contributes to prolonged outbreaks in medical wards and nursing facilities.
The rise of Candida auris is noted by the CDC as indicative of a wider increase in antifungal resistance, a trend attributed partly to the overuse and misuse of antifungal medicines in both medical and agricultural contexts.
Researchers recommend several actions to address C. auris, including:
- Developing novel antifungal agents with broad-spectrum activity.
- Improving diagnostic tests.
- Creating immune- and vaccine-based therapies for high-risk patients.
- Increasing awareness of fungal diseases through enhanced surveillance, particularly in regions with limited resources.
Recent research published in Communications Biology identified a potential vulnerability in C. auris. A study using a living-host model revealed that the fungus activates specific genes to acquire iron during infection, a nutrient essential for its survival. This suggests that targeting the iron scavenging process could lead to new treatments or enable the repurposing of existing medications.
Healthcare providers are advised to adhere to stringent infection control protocols, including enhanced cleaning practices, diligent hand hygiene, and patient isolation when necessary, to mitigate further dissemination. Ongoing monitoring and prevention efforts are considered essential.