Valley Fever

About Valley Fever

Coccidioidomycosis, commonly known as Valley Fever, is caused by the fungi Coccidioides immitis and Coccidioides posadasii. The fungi live in soil in arid regions, particularly the southwestern United States including Arizona and California. Spores are inhaled when soil is disturbed by wind, construction, or farming. Roughly 10,000 to 20,000 cases are reported annually in the US, but true numbers are likely higher. Most infections are asymptomatic or mild, but a minority develop serious or long term lung disease and around 1 percent or fewer develop disseminated infection affecting skin, bones, joints, or meninges. African Americans and Filipinos have higher risk of dissemination. The disease was first described in Argentina in 1892 by Alejandro Posadas. Climate change is expanding the geographic range of Coccidioides. Construction and agricultural workers are at highest risk. There is no vaccine. The NIH is funding vaccine development. Valley Fever is reportable in states where it is endemic.