TOOLS TO FIGHT BIVALVE VIRUSES
Researchers developed early detection and diagnostic tools for emerging bivalve aquaculture diseases to improve emergency preparedness, rapid response and regulatory decision-making.
Carolyn S. Friedman, University of Washington, School of Aquatic and Fishery Sciences
Brady Blake, Washington Department of Fish & Wildlife
Colleen Burge, University of Baltimore
Christopher Dugan, Maryland Department of Natural Resources
James Moore, California Department of Fish & Wildlife
Kimberly Reece, The College of William and Mary
Oyster aquaculture contributes millions of dollars to the Washington State economy. But emerging, rapidly spreading diseases such as the ostreid herpesvirus (OsHV-1) call for tools that will enable regulatory agencies and industry to respond effectively to such outbreaks. Towards that, researchers developed molecular and diagnostic tools and data for early detection of OsHV-1 and its variants. They also conducted field and laboratory trials to identify which oyster lines grow well when exposed to the virus. The viral genomes used in infection trials were sequenced to better understand how such diseases develop and to select resistant oysters.
Pacific oyster syndrome (POMS), caused by a DNA virus, threatens Pacific oyster populations globally. Since the disease first emerged in the 1990s, it has hit shellfish beds from France to California, killing millions of oysters and leaving growers reeling in its wake. In 2008,the virus mutated in several sites outside the U.S., becoming more lethal. Many Washington State oyster growers worry they could be impacted next. Understanding how POMS would affect Washington oysters is crucial to helping the industry avoid or overcome an outbreak of the virus should it strike.
The first year’s results suggest a wide variability in susceptibility of each oyster line to the virus. Kumamoto and Olympia oysters experienced low mortalities at all of the field sites, and Pacific oyster mortality ranged by particular stock and site. In the lab, Pacific oysters also varied in susceptibility to the French and Australian POMS strains. This information could eventually be used in breeding disease-resistant oysters, thought to be the most effective strategy for mitigating the spread of the virus.