Containment of a Candidozyma auris Outbreak in an Acute Care Hospital using a Comprehensive Screening and...

Candidozyma auris (C. auris) causes prolonged asymptomatic colonization and widespread silent healthcare transmission. An unknown proportion of patients who are colonized will progress to invasive candidiasis. Although culture has been the traditional method of colonization detection, PCR-based assays are now increasingly used for diagnosis and for evaluation of healthcare outbreaks.

During a six-month, multi-hospital unit C. auris outbreak in a 500-bed urban public hospital, screening transitioned from chromogenic culture to open-access low-throughput PCR and house-wide high-throughput PCR, mandated via electronic admission order sets. Infection prevention and control interventions included electronic health record contact tracing, "Contact Plus" precautions, double-bleach cleaning, dual UV-C disinfection, and ATP environmental monitoring. Whole genome sequencing evaluated clonality.

Admission screening was performed for all newly admitted patients and weekly surveillance testing for all inpatients during the outbreak, with testing scaled from 1,181 cultures to 1,539 low-throughput PCRs and 8,918 high-throughput PCRs, reducing median turnaround times from 82.1 to 37.6 and 20.3 hours, respectively. Twenty-nine colonized patients were identified, with 50% of secondary cases linked to bed spaces previously occupied by colonized individuals. Sequencing confirmed a highly clonal Clade I cluster. Transmission was halted only after introducing universal PCR screening alongside enhanced infection prevention and control interventions. Notably, no patients experienced symptomatic infection with C. auris or required antifungal therapy.

High-throughput, rapid PCR screening combined with rigorous infection prevention and control practices can successfully contain healthcare-associated C. auris outbreaks. Transitioning laboratory-developed tests to open-access, high-throughput platforms significantly enhances hospital outbreak response capacity.