These spores can be easily inhaled unknowingly. On reaching alveoli they enlarge in size to become spherules, and internal septations develop. This division of cells is made possible by the optimal temperature inside the body. Septations develop and form endospores within the spherule. Rupture of spherules release these endospores, which in turn repeat the cycle and spread the infection to adjacent tissues within the body of the infected individual. Nodules can form in lungs surrounding these spherules. When they rupture, they release their contents into bronchi, forming thin-walled cavities. These cavities can cause symptoms including characteristic chest pain, coughing up blood, and persistent cough. In individuals with a weakened immune system, the infection can spread through the blood. The fungus can also, rarely, enter the body through a break in the skin and cause infection. Diagnosis
Coccidioidomycosis diagnosis relies on a combination of an infected persons signs and symptoms, findings on radiographic imaging, and laboratory results. The disease is commonly misdiagnosed as bacterial community-acquired pneumonia. The fungal infection can be demonstrated by microscopic detection of diagnostic cells in body fluids, exudates, sputum and biopsy tissue by methods of Papanicolaou or Grocotts methenamine silver staining. These stains can demonstrate spherules and surrounding inflammation.With specific nucleotide primers, C. immitis DNA can be amplified by polymerase chain reaction (PCR). It can also be detected in culture by morphological identification or by using molecular probes that hybridize with C. immitis RNA.
In retrospect, Smith played a major role in both medical research and raising awareness about coccidioidomycosis, especially when he became dean of the School of Public Health at the University of California at Berkeley in 1951. Coccidioides immitis was considered by the United States during the 1950s and 1960s as a potential biological weapon. The strain selected for investigation was designated with the military symbol OC, and initial expectations were for its deployment as a human incapacitant. Medical research suggested that OC might have had some lethal effects on the populace, and Coccidioides immitis started to be classified by the authorities as a threat to public health. However, Coccidioides immitis was never weaponized to the publics knowledge, and most of the military research in the mid-1960s was concentrated on developing a human vaccine. Currently, it is not on the U.S. Department of Health and Human Services or Centers for Disease Control and Preventions list of select agents and toxins. In 2002, Coccidioides posadasii was identified as genetically distinct from Coccidioides immitis despite their morphologic similarities and can also cause coccidioidomycosis. Research
As of 2013, there is no vaccine available to prevent infection with  Coccidioides immitis or Coccidioides posadasii, but efforts to develop such a vaccine are underway. Other animals
Valley fever is not contagious. In dogs, the most common symptom of coccidioidomycosis is a chronic cough, which can be dry or moist. Other symptoms include fever (in approximately 50% of cases), weight loss, anorexia, lethargy, and depression.