Blastomycosis (Blasto)

Blastomycosis, or “blasto” is a fungal infection caused by the naturally occurring fungus, blastomyces. Although the disease is not common, there are several Lincoln County residents that are diagnosed every year with blasto, especially in fall and spring. You can get blasto by breathing in air around dirt that has been disturbed. Pay special attention when dirt is:

• Near a water source (lake or river) and has been disturbed.
• Moved by gardening, camping, hunting, hiking, riding all-terrain vehicles, or cleaning brush.
• Near an excavation or construction site.

Signs and Symptoms

Symptoms of blasto develop 2-15 weeks after being infected with blastomyces. Symptoms include:

• Cough
• Fever or chills
• Shortness of breath
• Chest or back pain
• Feeling very tired
• Skin sores that may look crusted and growing in size

Risk and Prevention

Blasto cannot be spread from person to person. Dogs can be infected with blastomyces, but cannot spread it to people. 

About half of people infected will not have any symptoms. People with a weakened immune system or a chronic illness are more likely to show symptoms. The best way to avoid serious illness:

• Talk to your healthcare provide when experiencing any symptoms. Blasto is treatable with antifungal medications.
• If you have been diagnosed with pneumonia, tell your healthcare provider if you may have been exposed to blasto.
• People who have weakened immune systems may want to consider avoiding activities that involve disrupting the soil in these areas.

DHS Fact Sheet Blastomycosis (English) DHS Fact Sheet Blastomycosis Employers and Workers (English)(Spanish) DHS Fact Sheet Blastomycosis and Pets  (English) Marshfield Clinic Blastomycosis Info graphic (English)

Useful Links:

• Blastomycosis – WI Department of Health Services
• Blastomycosis – Centers for Disease Control and Prevention