Valley Fever is primarily a disease of the lungs that is common in the southwestern United States and northwestern Mexico. It is caused by the fungus Coccidioides sp., which grows in soils in areas of low rainfall, high summer temperatures and moderate winter temperatures. These fungal spores become airborne when the soil is disturbed by winds, construction, farming and other activities. Infection occurs when a spore is inhaled. Within the lung, the spore changes into a larger, multicellular structure called a spherule. The spherule grows and bursts, releasing endospores which develop into spherules. Valley Fever symptoms generally occur within three weeks of exposure. Valley Fever is not a "contagious" disease, meaning it is not passed from person to person. Second infections are rare. |
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| DIAGRAM OF LIFE CYCLE |
Valley Fever derives its name from its discovery in the San Joaquin Valley of California, where it was also referred to as "San Joaquin Valley fever", "desert fever" or "desert rheumatism". The medical name for Valley Fever is coccidioidomycosis (often shortened to "cocci", pronounced KOK-SEE), meaning a fungal infection ("mycosis") caused by the fungus Coccidioides.
Valley Fever is prevalent in the San Joaquin and Central Valleys of California, and in the hot, desert regions of southern Arizona (especially in the Phoenix and Tucson areas), southern Nevada, southern Utah, southern New Mexico, western Texas (especially around El Paso), and Mexico (in the states of Sonora and Chihuahua). In addition, Coccidioides is found in semiarid and arid soils in Central and South America. Valley Fever can be a serious illness. It is estimated that there are about 150,000 cases in the southwestern U.S. each year, most of which resolve on their own. In patients with serious complications from the disease and those with immunosuppression (including AIDS and organ transplants), diagnosis and treatment is often complicated and expensive, and current therapy is sometimes inadequate to cure patients. Additionally, many visitors from regions where Valley Fever is not endemic develop Valley Fever after returning home from the Southwest, and their physicians may not be familiar with the disease.
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