Diversity of Candida spp. isolated from microbiota and infectious processes in wild mammals: a systematic review

Yeasts of the genus Candida are microorganisms of significant relevance in clinical practice, particularly within intensive care units, where they are classified as high-risk pathogens due to their impact on immunocompromised patients. Despite this, fungi frequently remain neglected in comparison to other infectious agents, and their ecological role, specifically concerning wildlife, remains underexplored. Historically, wild animals have been utilized as a source of subsistence by riverside and rural communities, although such consumption has been increasingly regulated in recent years. The interaction among wild animals, domestic species, and humans facilitates microbial exchange across diverse ecological niches, thereby increasing the risk of the transmission of pathogenic microorganisms and underscoring the principles of the One Health concept. Accordingly, this literature review consolidated studies regarding the isolation of Candida spp. from commensal sites and infectious processes in wild mammals. Thirty-four studies were analyzed, encompassing 21 Candida species across 74 mammalian species. Although Candida spp. are present in the vast majority of healthy individuals, their presence in free-ranging animals may serve as an indicator of ecological alterations and anthropogenic influence within these habitats. Furthermore, under specific circumstances, these commensals can cause infections, particularly in cases of immunological fragility. These data underscore the necessity for further research into the role of wildlife as hotspots or sentinels in the dissemination of these yeasts, contributing to the monitoring and management of emerging diseases, as well as to the health and conservation of wild populations.