CausesBy Mayo Clinic Staff
The fungi that cause valley fever — Coccidioides immitis or Coccidioides posadasii — thrive in the arid desert soils of southern Arizona, Nevada, northern Mexico and California's San Joaquin Valley. They're also endemic to New Mexico, Texas, and parts of Central and South America — areas with mild winters and arid summers.
Like many other fungi, coccidioides species have a complex life cycle. In the soil, they grow as a mold with long filaments that break off into airborne spores when the soil is disturbed.
The spores are extremely small and can be carried hundreds of miles by the wind. Once inside the lungs, the spores reproduce, perpetuating the cycle of the disease.
May 27, 2015
- Ferri FF. Coccidioidomycosis. In: Ferri's Clinical Advisor 2015: 5 Books in 1. Philadelphia, Pa.: Mosby Elsevier; 2015. https://www.clinicalkey.com. Accessed April 23, 2015.
- Nimmer N, et al. Coccidioidomycosis. Pediatrics in Review. 2015;36:181.
- Nguyen C, et al. Recent advances in our understanding of the environmental, epidemiological, immunological, and clinical dimensions of coccidioidomycosis. Clinical Microbiology Reviews. 2013;26:505.
- Wilken JA, et al. Coccidioidomycosis Among Cast and Crew Members at an Outdoor Television Filming Event — California, 2012. MMWR. 2014;63:321.
- Galgiani JN, et al. Primary coccidioidal infection. http://www.uptodate.com/home. Accessed April 23, 2015.
- Longo DL, et al. Coccidioidomycosis. In: Harrison's Principles of Internal Medicine. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com. Accessed April 23, 2015.
- Coccidioidomycosis. Centers for Disease Control and Prevention. http://www.cdc.gov/fungal/diseases/coccidioidomycosis/index.html. Accessed April 23, 2015.
- Papadakis MA, et al., eds. Mycotic infections. In: Current Medical Diagnosis & Treatment 2014. 54th ed. New York, N.Y.: The McGraw-Hill Companies; 2015. http://www.accessmedicine.com. Accessed April 23, 2015.
- Coccidioidomycosis (Valley fever) — Jobs at risk. Centers for Disease Control and Prevention. http://www.cdc.gov/niosh/topics/valleyfever/risk.html. Accessed April 30, 2015.
- Bennett JE, et al. Coccidioidomycosis. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2010. https://www.clinicalkey.com. Accessed April 23, 2015.