Key Factors to Consider for Candida auris Screening in Healthcare Settings: A Systematic Review.

Background: Candida auris is an emerging fungal pathogen that is often multidrug-resistant. It can persist on skin and in hospital environments, leading to outbreaks and severe infections for patients at risk. Several countries and institutions are working on establishing guidelines and recommendations for prevention. This review aims to assess the evidence on factors associated with C. auris colonisation or infection, the duration of such colonisation, possible colonisation sites, and the risk of secondary cases to inform screening recommendations.

Methods: We systematically searched five databases for primary studies and systematic reviews of our four outcomes. We excluded studies on treatment, management, laboratory methods, drug resistance, and environmental screening. From each paper, we extracted relevant data and summarised them in tables. Main findings were described narratively.

Findings: We selected 117 studies for inclusion. Most of the studies were observational studies. Without taking the method of testing into account, the duration of C. auris colonisation varied, with up to and beyond a year being common. The predominant sites of colonisation were the axillae and groin, with the nares and rectum being less common sites. The risk of secondary cases saw considerable variation across the studies, and the secondary cases primarily involved patients and not healthcare workers. Critical care settings, invasive medical devices, recent antimicrobial use, and comorbidities were often associated with C. auris colonisation and infection.

Conclusion: Our review highlights that, despite relevant findings on factors influencing C. auris colonisation and infection, substantial gaps remain in the evidence supporting screening practices. Most studies were conducted reactively, in outbreak settings, and lack systematic protocols. Given these limitations, screening guidelines are likely to be more successful if grounded in medical theory and yeast microbiology rather than relying solely on current studies. Rigorous, well-designed research is urgently needed to inform future C. auris screening and control efforts.