Revisiting the Geographic Distribution of Dimorphic Mycoses in the U.S.

Rising numbers of histoplasmosis, coccidioidomycosis, and blastomycosis (dimorphic mycoses [DM]) cases outside the regions historically considered endemic have been observed. To better define these evolving geographic regions with respect to DM incidence, investigators analyzed data from Medicare's Chronic Conditions Warehouse from 2007 through 2016. The primary outcome was incidence of DM in each county. Incidence thresholds of 100/100,000 person years for histoplasmosis and coccidioidomycosis and 50/100,000 for blastomycosis were considered clinically relevant.

During the study period, 79,749 histoplasmosis diagnoses, 37,726 coccidioidomycosis diagnoses, and 6109 blastomycosis diagnoses were documented. Clinically relevant incidence of his…