Candida auris fungaemia outbreak in a tertiary care academic hospital and emergence of a pan-echinocandin resistant isolate, Greece, 2021 to 2023

After the start of the COVID-19 pandemic, a rapid rise in reported numbers and wide geographic spread of <i>Candida auris</i>-related invasive infections has been observed globally. However, the contemporary epidemiology of <i>C. auris</i> fungaemias in Greece remains unknown. An outbreak of <i>C. auris</i> bloodstream infections has been ongoing for almost 3 years in a Greek tertiary care academic hospital, with 89 <i>C. auris</i>-driven episodes appearing in five waves every 6-7 months following peaks in colonisation rates by 3-4 months. All isolates clustered in clade I and were genetically related, 84% were fluconazole-resistant and all were non-resistant to amphotericin B and echinocandins, except one pan-echinocandin-resistant isolate (<i>FKS1S639F</i> mutant) recovered from a patient on empiric therapy with anidulafungin. Notably, <i>C. auris</i> was in 2023 the most prevalent (34%) cause of candidaemia in our hospital. The accelerated and long-term transmission dynamics of <i>C. auris</i> fungaemia underscore the need for rigorous infection control measures, while antifungal stewardship is warranted to contain the selection of echinocandin-resistant isolates.