February 15-18, 2009 Washington State Convention Center Seattle ...

THE EMERGENCE OF VIRAL HEMORRHAGIC SEPTICEMIA VIRUS TYPE IVB IN THE
LOWER GREAT LAKES BASIN
Geoffrey H. Groocock*, Stephen A. Frattini, Geoffrey E. Eckerlin, Rodman G. Getchell, Gregory A. Wooster,
William T. Heath, Kristine M. Hope, Rufina N. Casey, John M. Farrell, James W. Casey and Paul R. Bowser
Aquatic Animal Health Program
Department of Microbiology and Immunology
College of Veterinary Medicine
Cornell University
Ithaca, New York 14853 USA
This presentation will present a timeline of events from the initial identification of viral hemorrhagic septicemia virus (VHSV)
type IVb in the Lower Great Lakes basin to the current extent of the disease in New York State waters. The emergence of
VHSV in New York State has provided more insight into the spread of a new pathogen into a naïve environment.
The first detection of VHSV in New York State waters occurred in May 2006. The virus was isolated and identified from a
mortality event of round gobies collected from the St. Lawrence River. The initial clinical signs displayed by these gobies and
resulting gross and histopathology will be presented.
Subsequent isolations of VHSV in 2006 included 21 different mortality or morbidity events from 16 locations, including the
Great Lakes, the St. Lawrence River and the first inland isolation in Conesus Lake. An initial surveillance effort among healthy
fish from the St. Lawrence River also detected VHSV in an additional 12 species.
In 2007 VHSV was diagnosed in a total of fourteen cases. These cases identified VHSV in the following new species in New
York State: gizzard shad, carp, rainbow trout and lake trout. New locations for 2007 included more locations along Lake Ontario
and Lake Erie, Skaneateles Lake, Seneca-Cayuga Canal, Little Salmon River and a private pond in Ransomville.
Detections of VHSV in 2008 were limited to isolations of the virus from round gobies. The impact of VHSV and the potential
future implications of this emerging pathogen will be discussed.
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