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Bacterial 🟡 Moderate ✓ Treatable

Pseudomonas Septicaemia

🦠 Pseudomonas fluorescens, P. anguilliseptica · Pseudomonadaceae

📋 Overview

Pseudomonas spp. are ubiquitous environmental bacteria that rarely cause disease in healthy fish. Outbreaks occur when fish are stressed by handling, poor water quality, or concurrent disease. P. anguilliseptica causes "sekiten-byo" (red spot disease) in Japanese eel farms.

📊 Key Facts

Causative Agent
Pseudomonas fluorescens, P. anguilliseptica
Agent Family
Pseudomonadaceae
Peak Mortality
40%
Onset to Peak
days
Geographic Range
Worldwide in freshwater and marine aquaculture
Transmission Routes
Water-borne, opportunistic under stress
Primary Host
Eel (Anguilla spp.), Freshwater fish generally
Treatment
✓ Available
Vaccine
✗ None / Experimental
First Described
1970

🩺 Clinical Signs

Haemorrhagic petechiae on skin, fin rot, ulcers, exophthalmia, darkened coloration, systemic septicaemia.

🔬 Symptoms

🔬
Petechial skin haemorrhages
Integumentary Acute
🔬
Fin rot
Integumentary Subacute
🔬
Ulcerative lesions
Integumentary Chronic

🧪 Diagnosis

Culture, biochemical identification (oxidase positive), PCR.

💊 Treatment

Oxytetracycline, fluoroquinolones (subject to regulations).

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Reduce stress, optimise water quality, avoid overcrowding.