🐾 Vet’s Guide to Blastomycosis in Cats: Symptoms, Treatment & Prevention in 2025 🐾

By Dr Duncan Houston BVSc

Blastomycosis is a systemic fungal infection caused by the organism Blastomyces dermatitidis. While more commonly diagnosed in dogs and humans, cats are also susceptible. This guide provides comprehensive information on blastomycosis in cats, tailored for Australian cat owners in 2025.

🔬 Understanding Blastomycosis

Blastomycosis is contracted through the inhalation of fungal spores, typically found in moist soil and decaying organic matter. Once inhaled, the spores can cause a primary infection in the lungs and may disseminate to other organs, including the skin, eyes, bones, and central nervous system.

🦠 Causes and Risk Factors

Cats become infected by inhaling spores from environments where Blastomyces dermatitidis thrives. Risk factors include:

• 🐾 Living in or visiting areas with moist, acidic soil rich in organic matter.
• 🐾 Exposure to environments near water bodies, such as rivers and lakes.
• 🐾 Outdoor access, especially in endemic regions.

🐱 Recognizing Symptoms

Symptoms of blastomycosis in cats can vary depending on the organs affected. Common signs include:

• 🐾 Respiratory issues: coughing, difficulty breathing, nasal discharge.
• 🐾 Lethargy and weight loss.
• 🐾 Fever and decreased appetite.
• 🐾 Skin lesions or abscesses.
• 🐾 Eye problems: inflammation, redness, or blindness.
• 🐾 Lameness or limping due to bone involvement.
• 🐾 Neurological signs if the central nervous system is affected.

🧪 Diagnosis

Diagnosing blastomycosis involves:

• 🐾 Thorough physical examination and history taking.
• 🐾 Imaging studies like X-rays to assess lung involvement.
• 🐾 Cytology or histopathology to identify the fungus in tissue samples.
• 🐾 Fungal cultures, though they may take weeks for results.

💊 Treatment Options

Treatment typically involves antifungal medications:

• 🐾 Itraconazole: The preferred oral antifungal for cats.
• 🐾 Fluconazole: An alternative, especially if itraconazole is not tolerated.
• 🐾 Amphotericin B: Used in severe cases, administered intravenously.

Treatment duration can extend for several months, and it's crucial to continue medication even after symptoms improve to prevent relapse.

🛡️ Prevention Strategies

Preventing blastomycosis involves minimizing exposure to environments where the fungus is prevalent:

• 🐾 Keeping cats indoors, especially in endemic areas.
• 🐾 Avoiding activities that disturb soil in areas known to harbor the fungus.
• 🐾 Regular veterinary check-ups to monitor health.

📍 Considerations for Australian Cat Owners

While blastomycosis is more common in certain regions of North America, awareness is essential for Australian cat owners, especially those traveling with pets. Environmental changes and global travel can introduce new risks. Consult with your veterinarian about any concerns, especially if your cat shows unexplained respiratory or systemic symptoms.

📱 Stay Informed with Ask A Vet

For personalized advice and support, consider downloading the Ask A Vet app. Our platform connects you with licensed veterinarians for real-time consultations, helping you keep your feline friend healthy and happy.

🐾 Download the Ask A Vet app today and ensure your cat's well-being is always a tap away! 📲