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CMS Viral 🟠 Severe

Cardiomyopathy Syndrome

🦠 Piscine myocarditis virus (PMCV) · Totiviridae

📋 Definition

A chronic cardiomyopathy of large sea-water farmed Atlantic salmon caused by PMCV, characterised by progressive degeneration of the heart spongy layer.

📊 Key Facts

Causative Agent
Piscine myocarditis virus (PMCV)
Agent Family
Totiviridae
Genome Type
dsRNA
Peak Mortality
15%
Onset to Peak
months (chronic)
Geographic Range
Norway, Scotland
Transmission Routes
Horizontal, water-borne
Primary Host
Atlantic Salmon (large sea-water fish)
Treatment
✗ None
Vaccine
✗ None / Experimental
First Described
1985

🩺 Clinical Signs

Sudden death in large fish, pale/swollen heart, haemorrhage in pericardium, ascites, liver congestion.

🔬 Symptoms

🔬
Sudden death
Systemic Acute
🔬
Cardiac degeneration
Circulatory Chronic
🔬
Pericardial haemorrhage
Circulatory Acute
🔬
Ascites
Abdominal Subacute

🧪 Diagnosis

Histopathology (cardiomyocyte necrosis), RT-PCR for PMCV.

💊 Treatment

⚠️ No universally approved treatment is currently available. The information below covers supportive care and experimental approaches.
No treatment. Avoid crowding and handling of affected fish.

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
No vaccine. Minimise stress in large pre-harvest fish.