The comparative efficacy of antiseptics against Candida auris biofilms

Candida auris has emerged as a significant clinical entity due to its ability to cause outbreaks within the healthcare setting. A key feature of its nosocomial lifestyle is its ability to transfer between patients, yet little is known about the mechanisms behind this. A panel of C. auris clinical isolates was screened for their planktonic and sessile susceptibilities to skin disinfection challenge using povidone iodine, chlorhexidine and hydrogen peroxide. C. auris biofilms displayed increased tolerance to these strategies compared to planktonic cells. Additionally, analysis using a complex biofilm model demonstrated reduced susceptibility against clinically relevant concentrations of chlorhexidine and hydrogen peroxide, with complete eradication achieved only using povidone iodine. Principal component analysis (PCA) also revealed distinct clustering of C. auris biofilms in comparison to C. albicans and C. glabrata biofilms, and directionality with respect to different treatments. These findings indicate differential responses of different Candida species with respect to antiseptic challenge against biofilms, with C. auris appearing to be more resilient as a complex community.