Monster Seminar Jam - Viral hemorrhagic septicaemia virus (VHSV): the old and the new
Dr. Kyle Garver, Pacific Biological Station, Fisheries and Oceans Canada,
Viral hemorrhagic septicaemia virus is an aquatic pathogen that has recently received a resurgence of interest in North America. Since its first discovery in North America in 1988, it has been thought that VHSV is a pathogen of marine ecosystems rather than freshwater environments. Two decades of surveillance and monitoring of marine species demonstrated widespread marine reservoirs of VHSV and associated the virus with outbreaks in wild fish. Diseased marine fish ranged from cod in AK to mortalities of Pacific herring, sardines, and cultured Atlantic salmon in the marine waters off the coast of British Columbia. However in 2005 a new strain of VHSV (known as VHSV-IVb) was detected in the Great Lakes basin, the largest freshwater source in North America. The virus was initially detected in Lake Ontario and was associated with mass mortalities of freshwater drum. Since this discovery, VHSV-IVb has subsequently been found in all Great Lakes with the exception of Lake Superior and has also been identified in inland waters in New York, Wisconsin, and Michigan. The virus is infecting a broad host range of freshwater fish in the Great Lakes region with over 19 different species found to be susceptible to date, including but not limited to rainbow trout, yellow perch, large and smallmouth bass, walleye, and muskellunge. Phylogenetic analyses of multiple isolates taken from sites located throughout the Great Lakes area revealed that VHSV from the Great Lakes region was genetically related, but not identical, to isolates from the Atlantic coasts of North America suggesting that the virus was introduced into the Great Lakes via an eastern North American marine reservoir. Investigations aimed at characterizing North American strains of VHSV and possible modes of transmission will be discussed.
Date and Time:
February 28, 2008,
11:00 am - 12:30 pm