The Epidemiology of Coccidioidomycosis - 15 California Counties, 2007-2011 (POSTER)

Coccidioidomycosis or "Valley Fever" is a highly infectious disease caused by inhalation of the soil fungi Coccidioides immitis or C. posadasii.  Risk factors include occupational exposure to disturbed soil in endemic areas and exposure by visitors or new residents in those areas.  The current U.S. Centers for Disease Control and Prevention (CDC) map of the coccidioidomycosis endemic areas in the United States indicates that the known endemic area in California is restricted to the southern San Joaquin Valley.  The central coastal counties and all of southern California are listed as “possibly endemic”.  The CDC map may significantly under-estimate the coccidioidomycosis endemic areas of California. 

Image: www.cdc.gov

The California Coccidioidomycosis Collaborative met in 2012 to review the current epidemiology of the disease.  Fifteen California counties contributed a standardized coccidioidomycosis data set for the period 2007-2011.  The collaborating fifteen counties reported a total of 16,843 cases for the period 2007-2011. Kern County reported 46% of the collaborative cases.  Kern, Tulare, Kings and Fresno counties reported 76% of the cases.  If the 158 cases that Madera County reported to the state were added to the collaborating county data, the five counties classified as endemic for coccidioidomycosis by CDC would still account for only 76% of the cases reported.  Four of the top ten counties in California by number of cases are located outside the San Joaquin Valley.  A significant number of coccidioidomycosis cases have been reported in areas of California presently designated by the CDC as only “possibly endemic.”  For the period 1997-2011, these areas of the state contributed substantially to the burden of coccidioidomycosis hospitalizations in California.   The under-diagnosis of coccidioidomycosis in the United States is generally acknowledged.  The appropriate designation of the endemic areas of California should lead to improved awareness of the risk of coccidioidomycosis by California physicians, environmental health specialists and industrial hygienists.