Candida auris: A growing threat in healthcare settings

In the past few years, Candida auris has emerged as a major threat to global health. In the United States, the number of reported cases has grown from 331 clinical cases and 696 screening cases in 2018 to 2,377 clinical cases and 5,754 screening cases in 2022.¹

Three factors account for the high level of concern about C auris among public health professionals, including the Centers for Disease Control and Prevention:

• It spreads rapidly, especially in healthcare settings
• It can cause serious, even life-threatening, invasive infections
• It is resistant to commonly used antifungal drugs

C auris is a type of yeast that may exist on the skin (called colonization) and not cause infection. Infection may occur in almost any body tissue. It can cause bloodstream infections, wound infections, and other infections, including respiratory and urine. C auris spreads most often by fomites, or objects or surfaces carrying the yeast, and can spread from person to person. Patients with indwelling catheters, feeding tubes, and central lines appear to be at higher risk for infection.

According to the CDC, “in the United States, C auris infection has primarily been identified in people with serious underlying medical conditions who have received multiple antibiotics, and who have had prolonged admissions to healthcare settings or reside in healthcare settings. Otherwise healthy people do not seem to be at risk for C auris infections but can be colonized on their skin.”²

Treatment of C auris infection can be challenging. Many cases respond to treatment with antifungal drugs called echinocandins. However, some cases of infection have proved to be resistant to these and other classes of antifungals, requiring prolonged, high-dose, multi-drug treatment. Treatment should be in consultation with an infectious disease specialist.

Preventing spread
The CDC recommends screening for C auris colonization for patients at high risk, including those with close contact with a confirmed clinical case, and those who have had an overnight stay in a healthcare facility outside the US, especially countries with documented cases of C auris. Colonization is detected by swabbing commonly affected areas, including the groin, axilla, and the nasal passages. More details are available from the CDC.³

Species-level testing is necessary to identify C auris. For surveillance testing, Quest Diagnostics provides qualitative real-time PCR testing. PCR provides the species-level identification that healthcare facilities need to understand their risk of an outbreak.

For diagnostic testing, the CDC recommends that healthcare facilities “work with your laboratory to ensure the fungus identification method used in your facility can identify C auris.” If it cannot, suspected isolates should be sent out for specialized testing. Cases of C auris are a nationally notifiable condition; some states require reporting as well.

For diagnosing suspected active infection with C auris (patients with signs or symptoms), Quest offers culture testing using methodology that correctly identifies C auris.

References

1. Centers for Disease Control and Prevention. Tracking Candida auris. Accessed April 3, 2023.
    https://www.cdc.gov/fungal/candida-auris/tracking-c-auris.html 
2. Centers for Disease Control and Prevention. Healthcare Professionals FAQ. Accessed April 3, 2023. 
   https://www.cdc.gov/fungal/candida-auris/c-auris-health-qa.html
3. Centers for Disease Control and Prevention. Screening for Candida auris Colonization. Accessed April 3, 2023. 
   https://www.cdc.gov/fungal/candida-auris/c-auris-screening.html