Coccidioidomycosis, commonly referred to as Valley Fever, is caused by the soil-borne saprophytic fungus C. immitis and posadasii. These species have historically been found in the desert southwest and Mexico; however, in 2010 there were three coccidioidomycosis cases identified in central Washington. Colonization of soils by C. immitis has been confirmed at exposure sites associated with these cases. Multiple studies have identified a relationship between environmental conditions and C. immitis growth areas, but these relationships have not been evaluated in Washington. The Washington State Department of Health has been conducting environmental surveillance in an effort to understand the geographic distribution of C. immitis in central Washington and the associated risk to humans and animals. Here we describe our environmental surveillance efforts and present preliminary findings related to environmental conditions of C. immitis growth areas in central Washington.
Our objective is to describe the environmental conditions associated with confirmed Coccidioides immitis growth and accumulation sites in south central Washington in an effort to understand the ecology and identify additional potential sites across this emerging endemic zone.