Brooke Byars

Graduate Student, PhD


Dr. Jon Chorover


Environmental Science


Coccidioides Hot Spots and Hot Moments: Characteristics and Dynamics of Valley Fever-Ridden Arizona Soils

Coccidiomycosis, more commonly known as Valley Fever, is a lung disease caused by inhalation of the fungal arthroconidium, or “spore,” of Coccidioides spp. The endemic region of Coccidioides was previously defined by lower elevation semi-arid regions in the southwest United States, including regions of Arizona, California, Nevada, New Mexico, Utah, and Texas. However, the region is thought to be expanding based on case reports of Coccidioidomycosis and subsequence Coccidioides isolation from the soils in Washington State and northeastern Utah. The factors controlling the geographic range and distribution of Coccidioides are not well understood, although climate, environment, and soil properties are likely important. Chemical and physical properties including, mineralogy, major elemental composition, pH, salinity, organic matter, texture, soil temperature, and soil moisture will be analyzed in Coccidioides positive soils from Arizona, and compared to negative soils, to determine conditions that are essential to fungal growth and constrain Coccidioides habitat. Results from this project will be combined with results from other work in a Tri-University Collaboration, funded by the Arizona Board of Regents, to develop a better understanding of Coccidioides ecological niche, distribution models, to identify risk and reduce exposure, and predictive models for the geographic range that is likely to expand with the changing environment.