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LCD Viral 🟢 Mild

Lymphocystis Disease

🦠 Lymphocystivirus (LCDV) · Iridoviridae

📋 Overview

Lymphocystis is one of the most recognisable and widespread fish viral diseases. Infected fibroblast cells become massively enlarged (up to 1000× normal volume), forming distinctive cauliflower-like nodules. Mortality is generally low but the disfiguring lesions reduce market value in aquaculture and affect ornamental fish significantly.

📊 Key Facts

Causative Agent
Lymphocystivirus (LCDV)
Agent Family
Iridoviridae
Genome Type
dsDNA
Peak Mortality
5%
Onset to Peak
weeks
Geographic Range
Worldwide, >150 host species
Transmission Routes
Water-borne, through skin wounds
Primary Host
Flounder, perch, pike, many ornamental fish
Treatment
⚠ Supportive only
Vaccine
✗ None / Experimental
First Described
1874

🩺 Clinical Signs

White, grey or pink wart-like nodules on skin, fins, and occasionally gills; lesions may coalesce; fish may become lethargic.

🔬 Symptoms

🔬
Wart-like skin nodules
Integumentary Chronic
🔬
Fin deformity
Integumentary Chronic

🧪 Diagnosis

Clinical signs, histopathology (giant hypertrophied cells with basophilic inclusion bodies), PCR.

💊 Treatment

ℹ️ Treatment options are supportive. Consult a qualified fish health professional.
No effective antiviral. Remove infected fish. Lesions may resolve spontaneously over weeks to months.

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Prevent skin injuries, reduce stocking density, good water quality.