Coccidioides immitis is a fungus that causes a disease known as coccidioidomycosis, or valley fever. It primarily thrives in arid regions, particularly in the southwestern United States, Mexico, and parts of Central and South America. The fungus is found in soil and can become airborne, leading to inhalation by humans and animals. Once inhaled, Coccidioides immitis can cause respiratory symptoms, such as cough, fever, and chest pain. In some cases, it can lead to more severe complications, especially in individuals with weakened immune systems. Diagnosis typically involves laboratory tests, and treatment may include antifungal medications.