The VHS virus has been found in many places throughout the globe, and is widespread in many areas. For example, in Wisconsin the VHS virus has infected both Lake Michigan and Lake Superior, as well as the Lake Winnebago system. In VHS is also suspected to have made it’s way into the upper Mississippi River and Lower Wisconsin river as well, however there is not sufficient evidence to support that the virus has actually moved into these waters.

Across the globe, VHS has been found in a number of places.  In Europe, the virus has been found in Britain, France, Ireland, Greenland, Denmark, Finland and Norway. The Black Sea, the Baltic Sea, Both oceanic coastlines in North America as well as the great lakes, Japan, and Korea have also been discovered to carry fish infected with the virus.

A Phylogenetic tree of the different VHS strains, property of Nicolas Kapecki

Type I was the only known strain of VHS up until 1988, when type IV-a was found in the Pacific Northwest of the United States. Since then, other strains have been found, and it can be guessed that this was the viruses' genetic progression from the areas it has been found in. Type I-a was found in regions of continental Europe. From there, the disease moved to the Baltic Sea and East Asia, where Type I-b has been found. This likely gave rise to the Type IV strains in the America's, and the Type II strain in the Baltic Sea. Types III and I-c through e are all found in Europe, and likely rose from Type I-a. This tree is based strictly on geographical evidence

Though strains of the virus may vary from country to country, the overall effect on the fish population carries the same deadly results. This virus is affecting economies on a global scale.

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