The Impact of Climate Change on Human Fungal Pathogen Distribution and Disease Incidence

This review aims to compile the current knowledge on the impact of climate change on human pathogenic fungi. Ongoing surveillance of the fungal lineages described here will be imperative to predict disease burden and geographic expansion.

Emerging infectious diseases are increasing in frequency and impact in response to anthropogenic expedited climate change. The simultaneous global emergence of the multidrug-resistant fungus Candida auris has been hypothesized to be intimately related to warming temperatures. Diverse evolutionary pressures, including higher average temperatures caused by climate change and conditioning of pathogens to endothermy, has contributed to antifungal resistance in several fungal lineages. Endemic fungi (e.g., species of Coccidioides, Blastomyces, and Histoplasma) known to be largely constrained by environment and host range are expanding in distribution and increasing disease burden. The COVID-19 pandemic illuminated the vulnerability of human populations to aspergillosis and mucormycosis co-infections. The increasing frequency of extreme weather events presents favorable circumstances for opportunistic fungal infections.

Long-term shifts in temperatures and weather patterns are anticipated to influence emergence, expansion, and virulence of human pathogenic fungi. This includes warming temperatures and stochastic precipitation that may aid in expanding the distribution of several endemic fungal pathogenic lineages and increase disease burden. Here, we review both long-term climate patterns and short-term environmental disruption events that affect dispersal and incidence of human pathogenic fungi. Population growth, urbanization, intercontinental travel, and increased human longevity coupled with progressively damaging climate change effects generate conditions that make communities increasingly vulnerable to fungal pathogens.