Candida auris — a fungus with attitude

The COVID-19 pandemic has driven a significant shift in both awareness and practical application of improved infection prevention and control practices. The pandemic has driven advances in disease prevention from hand hygiene, environmental cleaning and disinfection, to improved Infection control awareness.

However, there are still many other pathogens that need to be eliminated to best protect patients, staff and the general public. Maintaining a singular pathogen focus on COVID-19 potentially exposes us to greater risk of and things other pathogens, which will lead to increased adverse health outcomes and morbidity. Primarily this is due to the different products, methods and disinfectant efficacy that need to be factored when dealing with the complex multi-pathogen risks.

Candida auris (C.auris) is a fungus from the same group of germs that cause thrush (Candida albicans) or serious blood stream infections in immune-compromised patients (C.glabrata, C.parapsilosis, C.krusei and C.tropicalis). Unlike most of the other candida species which live in the gastrointestinal tract, this fungus is also commonly found living on the skin. It is more resistant than other fungi to common treatments and over 90% of C.auris cases to date have been resistant to Fluconazole, the standard treatment for Candida infections.

Multi-resistant C.auris has only emerged relatively recently; it was first identified in Japan and South Korea. C.auris is of particular interest to clinicians due to the following characteristics of the fungus:

• Pathogen — it causes disease
• Risk to all patients
• Misclassification in laboratory diagnostic tests
• Few treatment options
• Easily spread
• Resistant to environmental disinfection

Healthcare facility outbreaks

As with other resistant pathogens, C.auris has been implicated in hospital outbreaks around the world. A large outbreak lasting over 12 months between 2015 and 2016 in a London resulted in 50 cases. Contact with an environment contaminated with C.auris was found to be a significant source of infection with the fungus.

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Infection prevention and control

C.auris cases should be taken very seriously in all healthcare facilities and strict measures put in place to prevent spread to other patients as follows:

1. Notify IPC and infectious diseases experts
2. Isolate patient with contact and isolation precautions
3. For symptomatic disease, consult with infectious disease specialist and begin treatment
   a. (treatment of asymptomatic colonization is not recommended)
4. Contact tracing and screening to determine local transmission risks
5. Increase environmental disinfection

Environmental disinfection

Removing C.auris from environments is a challenge due to the ease which it spreads and its resistance to common cleaning agents. The environment can remain contaminated for weeks. Subsequently many guidelines for the management of these infections advise daily and terminal or discharge cleaning with a strong environmental disinfectant such as a sporicidal disinfectant.

As with all environmental disinfection options, success will be easier if the area is regularly cleaned so that surface biofilm is not allowed to build up. Importantly as with other pathogens ensuring suitable contact time exposure to the disinfectant and sporicidal agent is essential in effective outcomes and pathogen reduction.

Summary

Multi-drug resistant Candida auris is an important pathogen which demands attention and action when identified in the healthcare setting. As well as implementing common IPC measures, disinfection of a potentially contaminated environment must be a priority. Always follow requisite guidelines for managing this pathogen and ensure contact times are enforced, noting that for any disinfectant or sporicidal agent the contact times against different pathogens may vary.

References

^{Schelenz, Silke, et al. "First hospital outbreak of the globally emerging Candida auris in a European hospital." Antimicrobial Resistance & Infection Control 5.1 (2016): 35.}

^{Schwartz, Smith & TC Dingle. “Something wicked this way comes: What health care providers need to know about Candida auris”. Can Commun Dis Rep (2018);44(11):271–6.}

Image caption: iStockphoto.com/Dr_Microbe