Infectious Salmon Anemia

ISA-infected fish may show one or more of the following symptoms:

• Pale gills
• Raised scales
• Pinpoint areas of bleeding
• Bloated abdomen
• Bulging eyes
• Swimming close to the surface

In some cases, ISA-infected fish won't show any signs of illness. They maintain a normal appetite and then die suddenly.

Because the signs of ISA can occur with other fish diseases, testing for ISA is the only way to determine if a fish has the disease.

ISA can spread via contact with infected fish and water contaminated with the virus. Biosecurity can help prevent it from infecting aquaculture facilities.

If you're a fish producer, here's what you can do:

• Clean and disinfect equipment between uses.
• Do not share equipment or transfer fish between sites.
• Coordinate stocking of farms in shared waters.
• Quickly remove any potentially sick or dead fish.
• Farm only one age group of fish at a time.
• Control facility access.
• Obtain eggs and brood stock that are tested ISA-free.
• Leave sites empty between production cycles (fallowing).
• Work with other producers to coordinate biosecurity among sites.
• Conduct regular surveillance for disease and report any signs or symptoms.
• Discuss vaccination with your veterinarian.

There is no treatment for ISA. If found on a farm (land-based or in open water), APHIS will work with the farm owner and State authority to respond to the detection. Each response is case specific and may include additional sampling of the affected population, a biosecurity review, and the development of a controlled marketing plan.