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SRS Bacterial 🔴 Fatal 🔔 OIE Notifiable 💉 Vaccine Available

Piscirickettsiosis

🦠 Piscirickettsia salmonis · Piscirickettsiaceae

📋 Definition

A salmonellosis-like rickettsial disease of salmonids caused by the obligate intracellular bacterium Piscirickettsia salmonis, causing systemic infection and high mortality.

📊 Key Facts

Causative Agent
Piscirickettsia salmonis
Agent Family
Piscirickettsiaceae
Peak Mortality
40%
Onset to Peak
2–6 weeks
Geographic Range
Chile (primary), Norway, Canada, Scotland
Transmission Routes
Water-borne, horizontal
Primary Host
Atlantic Salmon, Coho Salmon, Rainbow Trout (Chile)
Treatment
⚠ Limited
Vaccine
✓ Available
First Described
1989
Economic Impact
Largest disease cost to Chilean salmon industry — >US$100M/year

🩺 Clinical Signs

Pale gills, lethargy, pale/mottled liver, haemorrhagic kidney, ulcerative skin lesions, exophthalmia.

🔬 Symptoms

🔬
Pale mottled liver
Hepatic Subacute
🔬
Haemorrhagic kidney
Renal Acute
🔬
Ulcerative skin lesions
Integumentary Subacute
🔬
Lethargy
Systemic Acute

🧪 Diagnosis

PCR (gold standard), immunofluorescence, culture in fish cell lines (difficult).

💊 Treatment

ℹ️ Treatment options are limited. Consult a qualified fish health professional.
Florfenicol and oxytetracycline (limited efficacy due to intracellular location). High antibiotic use in Chilean industry.

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Vaccination (limited efficacy), biosecurity, site fallowing.