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VHS Viral 🔴 Fatal 🔔 OIE Notifiable

Viral Haemorrhagic Septicaemia

🦠 Viral haemorrhagic septicaemia virus (VHSV) · Rhabdoviridae

📋 Overview

VHS has the broadest host range of any fish virus — over 80 wild and farmed species are susceptible. It is a major threat to rainbow trout aquaculture in Europe and caused catastrophic mortality events in Lake Erie and the Great Lakes after introduction of the IVb strain in 2005.

📊 Key Facts

Causative Agent
Viral haemorrhagic septicaemia virus (VHSV)
Agent Family
Rhabdoviridae
Genome Type
ssRNA, negative-sense
Serotypes
Genogroups I–IV
Peak Mortality
80%
Onset to Peak
2–3 weeks
Geographic Range
Europe (all), North America Great Lakes (VHSV IVb), North Pacific
Transmission Routes
Water-borne, horizontal, wild carrier fish (herring, sprat)
Primary Host
Rainbow Trout, Turbot, Herring, >50 species
Treatment
✗ None
Vaccine
✗ None / Experimental
First Described
1938

🩺 Clinical Signs

Haemorrhages in muscle, eyes, skin and viscera; exophthalmia; anaemia; abnormal swimming; darkening of skin.

🔬 Symptoms

🔬
Petechial haemorrhages in muscle
Musculoskeletal Acute
🔬
Exophthalmia
Ophthalmic Acute
🔬
Skin darkening
Integumentary Subacute
🔬
Anaemia
Circulatory Acute

🧪 Diagnosis

Cell culture (BF-2, EPC), RT-PCR, virus neutralisation test.

💊 Treatment

⚠️ No universally approved treatment is currently available. The information below covers supportive care and experimental approaches.
No treatment available. Stamping out on farms.

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Biosecurity, movement restrictions, disinfection of water supply.