Cases of a deadly, drug-resistant fungus are spreading across the United States, according to the Centers for Disease Control and Prevention.
Candida auris, or C. auris, is a species of fungus that grows as a yeast and has been detected in more than half of U.S. states so far this year, according to CDC data. Approximately 3,437 clinically confirmed cases have been reported in 27 states as of the week ending July 25, which is still about 1,000 fewer cases than the same week last year. But the pace of emerging infections has the United States on track to reach 2025’s full-year total of 4,290 before the end of 2026.
Federal health data shows that C. auris cases have increased every year since 2019, with the largest annual jump occurring between
2022 and 2023, when cases rose 53.7%. While the total number of detected infections has grown yearly, the CDC said the rate of increase has dropped since 2022-2023. It also noted that more reported infections don't necessarily mean more infections overall; other factors, such as more robust screening and earlier diagnosis, could also account for the increase.
Still, rising cases each year is a concern to health authorities for two primary reasons: The fungus is largely drug-resistant, and it most commonly spreads in healthcare settings where people may already be sick or at-risk. People can also spread it without showing signs of illness themselves.
See which states have cases of C. auris
The Pacific region, which includes Alaska, California, Hawaii, Oregon and Washington, has been hit the hardest with 886 cumulative cases. California is reporting the most single-state infections, with 873 cases the week ending July 25.
What is C. auris? What are the symptoms?
C. auris is a fungus, manifesting as a yeast, that most commonly spreads in healthcare settings, such as hospitals and long-term care facilities. It is transmitted via direct contact with an infected person or contaminated surface, according to the Cleveland Clinic, which adds that it isn't naturally occurring on your body like some other types of Candida.
The fungus can cause serious illness, ranging from mild skin infections to life-threatening sepsis, per the CDCand Cleveland Clinic. Generally speaking, people with a healthy immune system can fight off a C. auris infection, but those with weakened immune systems are at risk.
The fungus can be present on the skin without causing any symptoms, meaning people can spread it to others without ever knowing they carried it.
Symptoms include those of other infections, according to the Cleveland Clinic, such as:
- Fever and chills
- Lethargy
- Low blood pressure and body temperature
- High heart rate
- Pain, pressure or feeling of fullness in your ear (ear infection)
Why is it hard to treat?
C. auris is difficult to treat because it is resistant to most drugs used to fight fungal infections. A CDC analysisof a 2022-2023 outbreak, published in February, found that 95% of C. auris samples did not respond to fluconazole, a first-line antifungal treatment. Another type of medication, called echinocandins, can be used to treat it in many cases, but some strains have also shown resistance to this drug. Doctors may sometimes combine several medications to find an effective treatment, according to the CDC.
C. auris was first detected in the United States in 2016 and has been on the rise since 2019, meaning a lot of research still needs to be done. The mortality rate is unknown, though some studies suggest a range of roughly 30% to over 60%. Major risk factors include the use of breathing and feeding tubes and catheters, which are medical interventions used on people who are already in poor health.
"Most patients who become sick with C. auris were already very sick," the CDC said. "When patients with C. auris die, it is hard to know how much C. auris contributed to their death compared to other pre-existing illnesses."
It's important to note that cases remain relatively rare and are primarily a concern in medical settings. Proper sanitation, sterilization, hygiene and, when necessary, isolation, can help stop the spread.
This article originally appeared on USA TODAY: This deadly drug-resistant fungus is spreading. See affected states
