UC Santa Barbara

In an era of increase of emerging infectious diseases, fungal pathogens have historically received little attention despite their growing importance 1–4. Fungal infectious disease emergence events began increasing dramatically in the 70s and 80s 5, and global anthropogenic change will likely cause this trend to continue. Fungal pathogens require unique methods for detection, modeling, management, and therapeutics; yet tools for understanding and mediating fungal pathogens are underdeveloped 2,4. While different in many ways from other pathogen classes, fungal pathogens nonetheless can have similarly devastating impacts on forests, crops, wildlife, and humans 1,3,6–8. The understudied nature of fungal pathogens coupled with a predicted rise in occurrence makes learning more about these organisms critical.

Developing tools for monitoring fungal pathogen emergence is challenging due to their unique characteristics which set them apart from other pathogen groups. Specifically, long-lived environmental stages, saprobic reproduction, and a broad host range can make detection, risk estimation, and understanding of disease dynamics difficult 6,9. New, readily-available molecular methods for fungal detection are recent 10, and the low number of organisms often required to induce infection is poorly matched with PCR detection limits that often require relatively high loads 11.

Batrachochytrium dendrobatidis (Bd) is a primary example of a fungal pathogen which has caused devastating global declines and for which new methods are required for detection and prediction. In my PhD thesis, I explore three questions: (1) can we detect Bd on environmental reservoirs; (2) can we predict Bd in amphibians using only information about the amphibian’s habitat; and (3) can Drosophila melanogaster be a vector of Bd, and be used to study invertebrate-Bd dynamics? Throughout the work presented here, I demonstrate how Bd may cause variable responses in amphibian populations (i.e., epidemic vs. endemic states), and understand more about how Bd interacts with its environment as a generalist, fungal pathogen rather than an amphibian specialist.