, Jorge Chavez, Thomas Iverson, John Hergert, Kelly Oakeson, Nathan LaCross, Chidinma Njoku, Andrew Gorzalski, and Daniel Gerrity
Figure 1. Culture-based isolation of Candida auris from wastewater, southern Nevada, USA, 2022, showing the effects of incubation temperature and fluconazole selection on competing organisms. A, B) Incubating the enrichment broth at 42°C (B) instead of 40°C (A) mitigated growth of competing filamentous fungi present in wastewater. C, D) Adding fluconazole to the salt Sabouraud dulcitol broth (SSDB) enrichment broth was essential for recovering C. auris from the southern Nevada wastewater samples. We plated 100 μL aliquots of inoculated enrichment broths incubated at 42°C after 2 days on HardyCHROM Candida medium (Hardy Diagnostics, https://hardydiagnostics.com) or BBL CHROMagar Candida medium (Becton, Dickinson, and Co., https://www.bd.com). Inoculation in SSDB without fluconazole resulted in overgrowth of an unidentified competing yeast (C), whereas inoculation in SSDB with fluconazole enabled isolation of C. auris colonies (D).