Climate change, animals, and Candida auris: insights into the ecological niche of a new species from a One Health approach.

BACKGROUND

One of the most puzzling traits of Candida auris is the recent simultaneous and independent emergence of five genetically distinct clades on three continents. Global warming has been proposed as a contributing factor for this emergence owing to high thermotolerance of C. auris compared with phylogenetically close Candida species. This hypothesis postulates that climate change induced an environmental ancestor to become pathogenic through thermal adaptation and was then globally disseminated by an intermediate host.

OBJECTIVES

The aim of this review is to compile the current knowledge on the emergence and ecological environmental niches of C. auris and highlight the potential role of animals in transmission.

SOURCES

A literature search was conducted using PubMed, MEDLINE, Google Scholar, and Web of Science from May 2022 to January 2023.

CONTENT

We discuss the up-to-date data on the ecological niches of this fungus and its mechanisms of emergence, transmission cycle in nature, and worldwide dissemination. We highlight the possibility of an originally intermediate host possibly related to marine or freshwater ecosystems on the basis of recent molecular and microbiological evidence from a One Health perspective. The consequences of harmful human impact on the environment in the rise of new fungal pathogenic species, such as C. auris, are also analysed and compared with other animal precedents.

IMPLICATIONS

The present knowledge can prompt the generation of new evidence on the ecological reservoirs of C. auris and its original mechanisms of environmental or interspecies transmission. Further research on the highlighted gaps will help understand the importance of the relationships between human, animal, and ecosystem health as factors involved in the rise and spread of emerging fungal pathogenic species.