Survival, Persistence, and Isolation of the Emerging Multidrug-Resistant Pathogenic Yeast Candida auris on a Plastic Health Care Surface

Abstract

The emerging multidrug-resistant pathogenic yeast <i>Candida auris</i> represents a serious threat to global health. Unlike most other <i>Candida</i> species, this organism appears to be commonly transmitted within health care facilities and causes health care-associated outbreaks. To better understand the epidemiology of this emerging pathogen, we investigated the ability of <i>C. auris</i> to persist on plastic surfaces common in health care settings compared with that of <i>Candida parapsilosis</i>, a species known to colonize the skin and plastics. Specifically, we compiled comparative and quantitative data essential to understanding the vehicles of spread and the ability of both species to survive and persist on plastic surfaces under controlled conditions (25°C and 57% relative humidity), such as those found in health care settings. When a test suspension of 10⁴ cells was applied and dried on plastic surfaces, <i>C. auris</i> remained viable for at least 14 days and <i>C. parapsilosis</i> for at least 28 days, as measured by CFU. However, survival measured by esterase activity was higher for <i>C. auris</i> than <i>C. parapsilosis</i> throughout the 28-day study. Given the notable length of time <i>Candida</i> species survive and persist outside their host, we developed methods to more effectively culture <i>C. auris</i> from patients and their environment. Using our enrichment protocol, public health laboratories and researchers can now readily isolate <i>C. auris</i> from complex microbial communities (such as patient skin, nasopharynx, and stool) as well as environmental biofilms, in order to better understand and prevent <i>C. auris</i> colonization and transmission.