Definition of Blastomycosis:

Blastomycosis is a rare infection that may develop when people breathe in (inhale) a fungus called Blastomyces dermatitidis, which is found in wood and soil.

Causes, incidence, and risk factors:

Blastomycosis occurs in people living in the south-central and midwestern United States and Canada. The infection is seen in 1-2 out of every 100,000 people in areas where the fungus most often occurs. It is even less common outside those areas.

Being around infected soil is the key risk factor.

The disease usually affects people with weakened immune systems, such as those with HIV or who have had an organ transplant. Men are more likely to be affected than women.