Candida Auris and Valley’s Vigilance

Recently, pieces in The New York Times and LA Times and on NPR¹ among others have highlighted a “Potentially deadly fungus spreading rapidly.” Given the popularity of the game and recent HBO series, “The Last of Us,” involving a pandemic of deadly fungal disease, this might be cause of some alarm. What is this all about? 

Candida auris is a yeast similar to Candida albicans, although not linked with mucosal infections such as thrush or yeast vaginitis and not anywhere near as pervasive. It was initially described in 2009 in Japan but probably has been present in Asia since 1996, when archived specimens found it in South Korea. It was originally linked to ear infections but over the years has also been firmly linked with blood stream and wound infections and possibly lung and urinary tract infections. Most victims of C. auris have had many co-morbid conditions and most were diagnosed either in hospitals or long-term care facilities. Co-morbidities have included immunocompromise, post-operative state, and diabetes, among others. Prolonged time in healthcare facilities, indwelling lines and devises, and previous heavy antibiotic and antifungal treatment have also been risk factors for this infection.  Given the severe underlying problems associated with this infection, it is not surprising that over 33% of patients with identified Candida auris infections die, although the role of the infection in these deaths is not always clear. 

Other than the potential for lethal infections, several other issues associated with C. auris make it an infection of concern. First, it can masquerade as other yeasts and be hard to identify. Systems such as Maldi-tof have improved our ability to identify these fungi as has awareness of the species it can hide as². Second, it can be spread readily in the environment from person to person, but also on fomites. It readily can become endemic in healthcare settings. And, it can be hard to remove from the environment once established, requiring bleach cleaning similar to Clostridium difficile. Third, it can be hard to treat. Resistance to azoles like fluconazole , amphotericin and even echinocandins such as micafungin has been reported. There have been strains that are resistant to all 3 classes³. Finally, it is spreading. It has now been reported in 30 countries, including the U.S. and 27 states, since it was first described. In the period between 2019 and 2021, seventeen U.S. states identified their first cases and 3,270 infections were identified in total, with 7,413 other colonized patients found on screening⁴. In 2022, there were an additional 2,377 cases and 5,754 other colonized patients⁵. Fortunately, to date, no cases have been identified yet in the Pacific Northwest, including Washington.   

So, what has UW Medicine | Valley Medical Center done to respond to this? Our recent collaboration with Labcorp has increased our ability to identify this organism should it appear in any of our clinical specimens. This is due to the expanded number of specimens in which species identification is occurring and enhanced technology not previously available to us. We have written policies in place for appropriate isolation and decontamination of rooms if C. auris is identified in a patient. Both our infectious diseases practitioners and our ID pharmacist are aware of the need for special therapeutic approaches needed when C. auris is a possible infection. Finally, and most importantly, we belong to the UW system and to a robust public healthcare system that will let us know if C. auris is in our area or if a potentially infected or colonized patient has been cared for in our system so we can respond with appropriate patient care and screening to make sure it does not spread and take hold here. 

In summary, Candida auris, while not turning people into zombies, is a potentially deadly infection of compromised patients that can be tricky to diagnose, hard to contain, and difficult to treat. Fortunately, it has not “invaded” our area yet, and with continued robust vigilance, it won’t in the future. 

References:

1. Archie, A “The potentially deadly Candida auris fungus is spreading quickly in the U.S.” NPR Health, March 21, 2023
2. Lockhart S et al “Tools for Detecting a “Superbug”: Updates on Candida auris Testing” J Clin Microbiol. 2022 May; 60(5): e00808-21
3. CDC “Candida auris” December 27, 2022
4. Lyman, M et al “Worsening Spread of Candida auris in the United States, 2019 to 2021” Annals of Internal Medicine March 20, 2023, https://doi.org/10.7326/M22-3469
5. CDC “Tracking Candida auris” February 14, 2023