142 • INFECTIONS CAUSED BY MOLDS 



individual reacting has had a sensitizing contact with the fungus 

 since few non-residents react to the test. This specific skin sensi- 

 tivity is usually acquired early in childhood by the residents of an 

 endemic area, usually without having had a recognized infection. A 

 small percentage (higher in those exposed for the first time as adults) 

 of reacting persons may have had a respiratory infection of some 

 clinical importance. Very few infected individuals (probably a small 

 fraction of 1 per cent of those who become skin sensitized) develop 

 the grave generalized form of the disease. During the period 1893 

 to 1931 only 254 cases of the generalized form were known from 

 California where it is a reportable disease. There is probably no 

 notable increase in the incidence of coccidioidal granuloma, except as 

 recent mass movements of susceptible adults in the armed forces 

 have enormously increased the number of exposures. However, since 

 1936 there has been a great increase in the recognition of the acute 

 respiratory type of the disease. Dickson suggested the latter be 

 designated primary coccidioidomycosis and that coccidioidal granu- 

 loma be called progressive or secondary coccidioidomycosis. 



Clinical. The present concepts of coccidioidomycosis have been 

 well summarized by Smith.^'^ Although primary skin lesions have 

 been reported in a few cases the important portal of entry is the 

 respiratory tract. Cases in which the time of exposure is known or 

 can be estimated accurately show that symptoms may appe&r 8 to 

 21 days after inhalation of the chlamydospores of the fungus and 

 skin sensitivity to coccidioidin is acquired 10 to 45 days after the 

 exposure. 



Initial or primary coccidioidomycosis , which follows inhalation of 

 the spores of the fungus, is self-limited and focalized in the lungs. 

 It is usually asymptomatic and is then recognized only by the acqui- 

 sition of skin sensitivity to coccidioidin. However, it may be an 

 acute respiratory condition following an influenzal or pneumonic 

 pattern. There may be pleural, joint, and muscle pains, headache, 

 cough which is usually non-productive, malaise, fever, chills, night- 

 sweats, and anorexia. In some cases there may be formation of 

 pulmonary cavities which close spontaneously and promptly, or per- 

 sist for a considerable time. It is estimated that 2 to 5 per cent of 

 individuals with initial coccidioidomycosis develop erythema no- 

 dosum or erythema multiforme. When this allergic manifestation 

 is present the disease is commonly called San Joaquin fever. Valley 

 fever, desert rheumatism, or desert fever, designations given to the 

 condition as it was seen within the endemic area of the San Joaquin 

 Valley of California long before its etiology was known. Human 



