The 1918 epidemic originated in the US[/QUOTE]
Thats one hypothesis but it is not established fact.
In addition, the haemagglutinin glycoproteins of the virus suggest that it was around far prior to 1918 and other studies suggest that the reassortment of the H1N1 virus likely occurred in or around 1915.[23]
and frome the same open source encyclopedia
Hannoun considered several alternative hypotheses of origin, such as Spain, Kansas, and Brest, as being possible, but not likely.[31] Political scientist Andrew Price-Smith published data from the Austrian archives suggesting the influenza began in Austria in early 1917.[34]
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