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Environmental 🟠 Severe

Thermal Stress Syndrome

🦠 Extreme water temperature events — both thermal shock and chronic sub-lethal stress · Non-infectious

📋 Definition

Physiological dysfunction and mortality caused by water temperatures exceeding (or falling below) the thermal tolerance range of a fish species.

📊 Key Facts

Causative Agent
Extreme water temperature events — both thermal shock and chronic sub-lethal stress
Agent Family
Non-infectious
Peak Mortality
100%
Onset to Peak
hours to days
Geographic Range
Worldwide
Transmission Routes
Non-infectious
Primary Host
All fish species; stenothermal species most vulnerable
Treatment
⚠ Supportive only
Vaccine
✗ None / Experimental

🩺 Clinical Signs

Loss of equilibrium, surface gasping, loss of schooling, erratic swimming, mass mortality in acute thermal shock. Chronic: reduced immunity, increased disease susceptibility, reduced growth.

🔬 Symptoms

🔬
Loss of equilibrium
Neurological Acute
🔬
Surface gasping
Respiratory Acute
🔬
Erratic swimming
Neurological Acute

🧪 Diagnosis

Water temperature measurement; absence of infectious agents.

💊 Treatment

ℹ️ Treatment options are supportive. Consult a qualified fish health professional.
Transfer to thermoregulated water if possible.

🛡️ Prevention

ℹ️ Prevention is the most effective strategy for managing this disease in aquaculture and aquarium settings.
Shade, flow-through cooling, careful site selection, climate change adaptation in aquaculture planning.