Figure 1. The mycobiota during health and in dysbiosis.

A) During homeostasis, diverse fungal communities reside all human barrier surfaces during homeostasis, such as the mouth³²; lung⁵³; skin⁹, gut²² and vagina⁵⁷ (left hand side). The pie charts represent the relative abundance of the observed taxa at the phylum and genus levels (inner and outer circles, respectively). Of note, the data for the vagina are estimates that are based on culture-dependent studies, due to a lack of sequencing-based studies related to disease conditions (indicated with an asterisk). ‘Other’ refers to sequences with <5% relative abundance. During diseases, those communities are perturbed (right hand side). Dysbiotic fungal communities are observed in the oral cavity³² and the vagina⁵⁸ of HIV patients; in the lung of cystic fibrosis patients⁵¹; on the skin of primary immunodeficiency⁶¹ and chronic wounds⁶³ patients; in the gut of Crohn’s disease²² patients. B) Factors contributing to fungal dysbiosis at different barrier surfaces. AF, antecubital fossa; HF, hind foot; STAT3, signal transducer and activator of transcription 3.