The epidemiology of blastomycosis in Illinois and factors associated with death.

Background: Blastomycosis is a systemic fungal disease that may be asymptomatic or progressive and may lead to death.

Methods: In response to a reported increase in the number of cases of blastomycosis in Illinois, surveillance data reported to the Illinois Department of Public Health from January 1993 to August 2003 were analyzed and the medical records of 4 patients who died were reviewed.

Results: Among the 500 cases reported, the median age of the patients was 43 years (range, 4-87 years), and 34 patients (7%) died. Higher rates of mortality were observed among persons who were black, who were > or =65 years of age, and who were male. The median time from onset of illness to diagnosis was 128 days (range, 12-489 days). Death was associated with a time from onset of illness to diagnosis of > or =128 days (OR, 2.1; 95% CI, 1.0-4.8). During the period from 1993 through 2002, the number of cases reported per year increased from 24 to 87 (P<.05).

Conclusions: The incidence of blastomycosis has been increasing in Illinois. To reduce mortality related to delay in diagnosis and treatment, medical providers need to be educated about blastomycosis, with an emphasis on symptom recognition, methods of diagnosis, and appropriate antifungal treatment.