07/10/2026
Blastomycosis: The Silent Killer Hiding in Our Backyards
As many pet owners in the Midwest know, blastomycosis is not rare, and unfortunately Illinois and Wisconsin are considered hot spots for this dangerous fungal disease.
Blastomycosis is caused by a fungus that lives in moist soil, decaying leaves, wooded areas, riverbanks, lakefronts, and areas rich in organic material. When the soil is disturbed, tiny spores become airborne and can be inhaled by your dog.
⚠️ There is NO vaccine. ⚠️ There is NO monthly preventative medication. ⚠️ Early symptoms often look like kennel cough, allergies, or a simple respiratory infection.
Areas that may carry a higher risk include:
🐾 Dog parks with dirt or mulch surfaces
🐾 Riverbanks and creek beds
🐾 Forest preserves and wooded trails
🐾 Construction sites and freshly dug soil
🐾 Areas with decaying wood or leaves
🐾 Hunting fields and training grounds
🐾 Swampy or muddy areas near lakes and ponds
🐾 Areas where dogs frequently dig or disturb the soil
Common symptoms include:
• Coughing or difficulty breathing
• Loss of appetite
• Weight loss
• Lethargy
• Eye redness or blindness
• Skin sores that won't heal
• Limping or swollen joints
• Fever and enlarged lymph nodes
Many dogs are very sick by the time they are diagnosed, which is why early veterinary care is critical.
💲 Treatment is expensive. Diagnosis often requires chest x-rays, bloodwork, urine testing, biopsies, and fungal testing. Diagnostic costs alone can run $1,500 to $5,000 or more, followed by months of antifungal medications. Treatment commonly lasts 3 to 6 months, sometimes longer.
📊 What is the survival rate?
The good news is that dogs diagnosed early and started on treatment quickly have a fighting chance. Studies show approximately 50% to 75% of dogs survive and recover with treatment, with some reports showing recovery rates approaching 70-80% in uncomplicated cases. Unfortunately, dogs with severe lung involvement have survival rates closer to 50% or less.
The difficult reality is that without treatment, blastomycosis is often fatal.
Living in the Midwest doesn't mean your dog should never enjoy the outdoors. It simply means we need to stay aware, recognize symptoms early, and seek veterinary care quickly if something seems off.
If your dog develops a persistent cough, unexplained weight loss, eye problems, lethargy, or skin lesions after spending time outdoors, ask your veterinarian whether blastomycosis should be considered.
❤️ Awareness saves lives. Early diagnosis saves lives. Please share this information with fellow pet owners throughout Illinois, Wisconsin, and the Great Lakes region.
