Candida auris cases have more than doubled in the United States since 2022, according to new data from the US Centers for Disease Control and Prevention, underscoring the rapid spread of a fungal pathogen that is increasingly resistant to treatment and capable of surviving on hospital surfaces for weeks.
Researchers at the CDC reported that the total number of clinical cases reached 6,197 in 2024, up from 2,882 in 2022. The number of clinical cases reported to the agency increased by 3,315 over that period, while cases detected during screening nearly doubled. The yeast was first identified in the US in 2016, but its global emergence is far more recent: C. auris (now reclassified as Candidozyma auris) was first isolated in Japan in 2009. Since then, more than 84,941 cases have been reported across 82 countries, with spread accelerating markedly after the Covid-19 pandemic. The US alone has reported over 65,321 cases as of 2025.
Resistance threatens frontline treatments
The rise in cases is particularly concerning because C. auris is becoming increasingly resistant to antifungal medications. While many infections can still be treated with a class of drugs called echinocandins, resistance is growing. According to the CDC, almost all isolates worldwide are resistant to fluconazole, a first-line antifungal. Some strains have developed resistance to multiple classes of antifungals, and pan-resistant strains — resistant to all available treatments — have been detected globally. Resistance can emerge rapidly while a patient is undergoing treatment.
In the UK, experience from the PHE Mycology Reference Laboratory indicates that while no multidrug-resistant strains were initially found, all isolates tested were resistant to fluconazole and often cross-resistant to other azoles. The UK Health Security Agency, which monitors C. auris as a notifiable organism in England from April 2025, has recorded 862 cases (both colonisations and infections) between January 2013 and September 2025. Annual numbers in England have risen steadily: 26 cases in 2021, 38 in 2022, 93 in 2023 and 178 in 2024. Independent UKHSA data from September 2025 put the 2024 figure at 212 cases. London remains the region reporting the majority of cases, and the fungus has been detected in 72 hospitals across the UK over the past two years.
How Candida auris spreads and why it is so difficult to treat
Candida auris spreads primarily through contact with contaminated surfaces or medical equipment, and via direct contact with infected or colonised individuals. Healthcare workers’ hands and clothing can also carry the yeast, and multiuse patient equipment such as thermometers has been implicated in outbreaks. The yeast can survive on radiators, windowsills, medical equipment and other surfaces for extended periods — weeks or longer — making it exceptionally hard to eradicate from healthcare environments.
A critical feature of C. auris is its ability to colonise patients without causing illness. Colonisation means the yeast is present on the skin or body but does not make the patient sick. According to the CDC, patients who are most likely to spread the yeast often show no symptoms; they are known as “colonised” patients, though both infected and colonised individuals can spread the fungus. UMass Memorial Health notes that colonisation can persist for two or more years after a treated infection, and there is currently no way to treat colonisation. The CDC stresses that people without underlying risk factors — including healthcare workers and visitors — generally do not carry or become sick from C. auris.
The infection typically affects people with severe underlying medical conditions. Common risk factors include indwelling medical devices (such as catheters and arterial lines), prolonged hospital stays, critical illness, a weakened immune system, diabetes, hypertension, renal failure, malignancy, and mechanical ventilation. Invasive infections can include bloodstream infections (candidemia), wound infections and ear infections. Symptoms may include severe, flu-like illness, low blood pressure, low body temperature and a high heart rate, and can lead to organ failure, sepsis and shock, according to the Cleveland Clinic.
Mortality rates are difficult to determine precisely because most patients who die already have other serious health problems. Globally, the mortality rate for invasive C. auris infections has been reported between 30 and 60 percent. In the UK, between January 2013 and September 2025, 15 percent of cases (115 out of 744) died within 60 days of a positive specimen, but the primary cause of death was attributed to other clinical causes for 99 percent of those. In a UK outbreak, no deaths were directly attributed to C. auris infection. The current all-cause mortality for C. auris cases in the UK is approximately 20 percent.
Prevention and screening
Healthcare providers can take several steps to prevent spread. The CDC recommends isolating infected patients, frequently cleaning rooms with special disinfectants effective against C. difficile spores, requiring staff to wear gloves and gowns, and ensuring visitors wash their hands with soap and water. Because patients colonised or infected with C. auris often carry the yeast on their skin or other body sites for a very long time, precautions are maintained until discharge.
The UK Health Security Agency echoes these measures: meticulous hand hygiene (alcohol-based rub or soap and water), single-room isolation or cohorting of colonised or infected patients, and use of hospital-grade disinfectants. Hydrogen peroxide vapour and UV light systems can supplement standard cleaning. Single-patient-use devices are recommended, and reusable equipment should be dedicated where possible.
Screening is a critical tool. The CDC states that screening is how healthcare providers and patients can know whether a patient is colonised and able to spread the fungus. In the UK, active surveillance is recommended for early identification, especially for patients with recent overnight stays in healthcare facilities outside the UK or from affected units. Since April 2025, laboratories in England are required to report C. auris cases to UKHSA as a notifiable organism.
The reasons for the increase in US cases remain unclear, but CDC researchers suggest improved screening and testing may have been a factor, along with the impact of the Covid-19 pandemic. In the UK, the fungus has been emerging over the past decade, with prolonged outbreaks in hospitals since 2015, and the UKHSA is actively working with NHS trusts to investigate outbreaks and strengthen detection and infection control measures.