Shrimp Disease Management: EMS, WSSV and Welfare Implications

Disease outbreaks in farmed shrimp cause mass mortality and significant welfare suffering; prevention is vastly preferable to treatment.

Key Facts

Early Mortality Syndrome (EMS/AHPND) caused by Vibrio bacteria kills shrimp within 35 days of stocking.
White Spot Syndrome Virus (WSSV) is a highly contagious viral disease causing 100% mortality within days of outbreak.
Both diseases cause rapid physiological deterioration; affected shrimp show lethargy, reduced feeding, and discolouration.
Biosecurity — water treatment, SPF stock, exclusion of wild shrimp — is the primary prevention strategy.
Probiotics and water quality management reduce Vibrio loads and disease susceptibility in well-managed ponds.
Vaccination against WSSV is in development but not yet commercially available for shrimp.

Welfare Considerations

Shrimp disease outbreaks cause suffering at enormous scale — billions of individuals affected annually. While shrimp sentience evidence is still being established, the precautionary principle supports minimising stress, injury, and disease. Prevention through biosecurity, genetics, and environmental management is both the most welfare-positive and economically rational approach. Mass culling of diseased ponds, while sometimes necessary, should be conducted as humanely as possible.

What You Can Do

Support shrimp aquaculture certification schemes that require documented biosecurity and disease management plans.
Choose products from certified producers with transparent disease management records.
Advocate for mandatory disease reporting in shrimp aquaculture to improve industry-wide surveillance.
Support research into WSSV vaccines and sustainable disease management alternatives to pond abandonment.