Aquaculture

Farmed Prawn Disease Management: EHP and WSSV Biosecurity

Emerging diseases including EHP (Enterocytozoon hepatopenaei) and White Spot Syndrome Virus threaten farmed prawn welfare and production. Biosecurity is the primary management tool.

Key Facts

WSSV can cause 100% mortality in farmed shrimp within 3-7 days of infection
EHP causes growth retardation and crowding syndrome, increasing suffering and mortality
Both pathogens spread rapidly through shared water and infected broodstock
PCR testing of broodstock and postlarvae is the most reliable detection method
Specific pathogen free (SPF) broodstock programmes have transformed disease management
Biosecurity gaps during stocking are the primary introduction route for both pathogens

Welfare Considerations

Shrimp experiencing WSSV infection or severe EHP infestation suffer significant welfare impacts before death - diseased animals show abnormal behaviour, lose the ability to feed normally, and die in large numbers. Mass mortality events represent welfare emergencies in which vast numbers of animals die unnecessarily. Prevention through rigorous biosecurity is both more effective and more welfare-positive than attempting to treat established disease outbreaks.

What You Can Do

Support certification schemes requiring biosecurity and disease monitoring standards
Ask retailers about disease management standards in their prawn supply chains
Advocate for SPF broodstock requirements in prawn farming regulations
Contribute to research into prawn disease prevention and welfare
Avoid prawn products from farms without transparent health management records