Sputum culture of Coccidioides immitis on Sabouraud's medium, showing white, cottony fungus growth.

Coccidioides immitis is a pathogenic fungus that resides in the soil in certain parts of the southwestern United States, northern Mexico, and a few other areas in the Western Hemisphere.

It, along with its relative Coccidioides posadasii, can cause a disease called coccidioidomycosis (Valley Fever), and it is a rare cause of meningitis, mostly in immunocompromised persons. It has been declared a select agent by both the U.S. Department of Health and Human Services and the U.S. Department of Agriculture, and is considered a biosafety level 3 pathogen.

In Popular Culture

Coccidioides immitis is used as a plot device in Thunderhead, a novel by Douglas Preston and Lincoln Child. The fungus (prepared from infected victims) is revealed to be the principal agent in corpse powder (based on corpse poison used by Witch (Navajo)). It was also mentioned by Dr Gregory House on the Television Series, House MD (episode Lines in the Sand).

External links

• Coccidioides
• Coccidioides immitis

Microscopic appearance of an old culture of Coccidioides immitis, showing fragmented chlamydospores. This is the infective form of the fungus occurring in nature.

Septate hyphae of Coccidioides immitis with 90 degree branching and thick walled barrel shaped arthoconidia alternating with empty cells.