Prospective study of Candida auris nucleic-acids in wastewater solids in 190 wastewater treatment plants in the United States suggests widespread occurrence

Candida auris is an emerging, multidrug-resistant fungal pathogen that poses a significant public health threat in healthcare settings. Despite yearly clinical cases rapidly increasing from 77 to 8,131 in the last decade, surveillance data on its distribution and prevalence remains limited. We implemented a novel assay for C. auris detection on a nationwide scale prospectively from September 2023 to March 2024, analyzing a total of 13,842 samples from 190 wastewater treatment plants across 41 U.S. states. Assays were extensively validated through comparison to other known assays and internal controls. Of these 190 wastewater treatment plants, C. auris was detected in the wastewater solids of 65 of them (34.2%) with 1.45% of all samples having detectable levels of C. auris . Detections varied seasonally, with 2.00% of samples positive in autumn versus 1.01% in winter (p<0.0001). The frequency of detection in wastewater was significantly associated with states having older populations (p<0.001), sewersheds containing more hospitals (p<0.0001), and sewersheds containing more nursing homes (p<0.001). These associations are in agreement with known C. auris epidemiology. This nationwide study demonstrates the viability of wastewater surveillance for C. auris surveillance, and further highlights the value of wastewater surveillance when clinical testing is constrained.