Coccidioidomycosis in Phoenix, Arizona.

Interest in the Incidence of coccidioidomycosis throughout the desert areas of the western slopes of the Rockies and the southwestern desert country has been accelerated by studies made at the airbases and by the many new endemic foci which have been discovered during the past three years. The purpose of this study is to attempt to evaluate the Importance of this infection in the civilian population of Phoenix and environs. Data have been accumulated that indicate that a large percentage of the population has been sensitized to the fungus. This observation is based largely upon the use of the coccidioidin skin test. Its significance seems to parallel to a large extent the significance of the tuberculin test. The diagnosis of this disease must in the majority of cases be based upon clinical manifestations, x-ray findings, and a positive coccidloidin test. It Is rarely possible to make an absolute diagnosis because it Is only occasionally found that the organism can be recovered on sputum examinations and by staining methods. Furthermore, the advisability of culture examinations in the laboratory Is questioned because of the hazard from cultures to the laboratory technician. In the last twenty years knowledge of coccidioidomycosis infections has progressed from the recognition of the extensive granulomatous lesions of the lungs, bones and joints, frequently terminating fatally to the present time when we know that infection with the fungus is usually mild and transitory and produces subclinical lesions more frequently unrecognized than diagnosed. The studies of Smith and others from 1937 to 1940 demonstrated that the San Joaquin Valley was the principal endemic area of the Pacific Coast and that there Is a close relationship between coccidioldomycosis and erythema nodosum and erythema multiforme. Farness focused attention on the problem of coccidloidomycosis Infection in the desert area of the Southwest by reporting ten cases in southern Arizona. Aronson, et al,3 in a study of Indians in the central Arizona desert areas found a large percentage reacting positively to coccidioldin, many of whom had negative tuberculin reactions yet calcification showing in chest x-ray films. Of 700 persons examined, 14.7 per cent reacted negatively to the tuberculin test but gave positive coccldioidin reactions. This further demonstrated the similarities between hyper-