In Vitro Antifungal Activity of Commonly Used Antiseptics and Disinfectants Against Candida auris Isolates.

OBJECTIVE

Candida auris (C. auris) has emerged as a multidrug-resistant nosocomial pathogen associated with outbreaks in healthcare settings and high mortality rates. Its ability to persist in the hospital environment highlights the importance of effective disinfection strategies. This study aimed to evaluate the in vitro susceptibility of clinical C. auris isolates to commonly used antiseptics and disinfectants under conditions reflecting routine clinical practice.

METHODS

Ten clinical C. auris isolates, along with reference strains of C. krusei (ATCC 6258) and C. parapsilosis (ATCC 22019), were tested. Sodium hypochlorite (5%, 1%, 0.5%), hydrogen peroxide (6%, 3%), povidone-iodine (10%, 5%, 2.5%), a chlorhexidine/n-propanol-containing liquid soap, and an ethanol/isopropyl alcohol-based hand disinfectant were evaluated by a qualitative suspension test at contact times of 1, 2, 5, 10, and 30 minutes. Growth inhibition was assessed after incubation.

RESULTS

Povidone-iodine at all concentrations, chlorhexidine/n-propanol-containing liquid soap, alcohol-based hand disinfectant, and sodium hypochlorite at 5% and 1% achieved complete growth inhibition of all isolates within the first minute. In contrast, 0.5% sodium hypochlorite and hydrogen peroxide showed reduced efficacy at early contact times. Growth was observed in some C. auris isolates after 1 minute of exposure to 6% hydrogen peroxide, and in a larger proportion of isolates after 1-2 minutes of exposure to 3% hydrogen peroxide. Similar variability was observed in reference strains, particularly with hydrogen peroxide.

CONCLUSIONS

Commonly used antiseptics and disinfectants are effective against C. auris when applied at appropriate concentrations and contact times. However, reduced efficacy at lower concentrations and with shorter exposure times underscores the importance of proper disinfectant use in preventing environmental persistence and transmission in healthcare settings.