Deadly fungus became resistant to all existing drugs in 3 unlinked US patients

A deadly fungal pathogen developed the ability to resist all existing antifungal drugs on three separate occasions in the United States, according to a new report.

The fungus, Candida auris, was already classified as an "urgent threat" by the Centers for Disease Control and Prevention. But the emergence of so called "pan-resistant" strains raises additional concern, according to the report's authors, who are infectious disease specialists at the CDC and the New York State Department of Health. They published their findings Thursday in the CDC's publication Morbidity and Mortality Weekly Report.

C. auris was first identified in 2009 in Japan and has since popped up in nearly 40 countries. (It arrived in the US by 2013, and New York City, Chicago, and New Jersey have been hit the hardest.) The insidious germ is known for creeping around healthcare facilities and infecting vulnerable patients, causing invasive infections marked by nondescript fever and chills.

Somewhere between 30 percent and 60 percent of patients die from the infection. (Determining the exact fatality rate is tricky because the fungus often preys upon patients already suffering from life-threatening conditions.)


Surveillance of strains collected in the latter half of 2019 turned up three patients with pan-resistant C. auris, the report says. The patients were all in different medical facilities and had no contact or connection with each other.

In all three cases, the patients' C. auris infections started out with strains that were susceptible to echinocandins and each was treated for prolonged periods with an echinocandin drug. After months on the drugs, subsequent testing showed that their once drug-susceptible infections had developed resistance to all classes of drugs available.

Two of the patients died within weeks of investigators isolating their pan-resistant strains in 2019.

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