Infectious hematopoietic necrosis virus: Certification and diagnostic testing

WADDL health aquatic lab
Jo-Lynn Reno, left, uses a microscope and a video display to examine a virus that is attacking fish cells as she works in the Aquatic Health section of the Washington Animal Disease Diagnostic Laboratory on Nov. 9, 2022, in the College of Veterinary Medicine at Washington State University Pullman. (College of Veterinary Medicine/Ted S. Warren)

What is infectious hematopoietic necrosis virus (IHNV) in fish?

Infectious hematopoietic necrosis virus (IHNV) infects fish across the world and is one of the most common viruses for which fish health regulators require testing. It is regularly detected in wild salmon populations in the Pacific Northwest and is endemic to the United States. IHNV can cause significant disease and mortality, particularly in sockeye salmon, which is why it is of concern to fish health regulators.

What should I know about certification testing for IHNV?

For producers moving fish interstate or internationally, fish health regulators will almost always require certification testing for IHNV following methodology from the American Fisheries Society-Fish Health Section Blue Book’s USFWS/AFS-FHS Standard Procedures for Aquatic Animal Health Inspections or the Aquatic Manual of the World Organization for Animal Health (formerly known as the OIE).Both testing methods use cell culture to screen fish tissues (such as ovarian fluid or tissue samples) for the virus, but they vary slightly in how they are performed. WADDL’s Aquatic Health Laboratory Section offers cell culture testing that clients can request to be performed following either the Blue Book or WOAH testing methods to meet their certification needs.

How long does it take to complete certification testing for IHNV?

Certification testing with cell culture takes 29 days to complete, so producers should schedule sample collection and submission with this timeframe in mind.

What diagnostic testing options for IHNV are available?

For producers whose fish are having increased morbidity and/or mortality, IHNV may be a disease their veterinarian recommends testing for. WADDL offers several different diagnostic tests for IHNv, including a PCR test that has a significantly faster turnaround time than traditional cell culture testing. WADDL has fish veterinarians with production, clinical, and diagnostic experience on staff available to answer veterinarians’ and producers’ questions about diagnostic testing for fish, including for IHNV.

How can I get more information about certification and diagnostic testing for IHNV?

For more information about testing aquatic species at WADDL, please call us at 509-335-9696.