H3N1 is a subtype of the species Influenza A virus, mostly affecting pigs.
The known subtypes of Influenza A virus that create influenza in pigs and are endemic in pigs are H1N1, H1N2, H3N1 and H3N2.
See also strains named by isolate Fujian flu strains named by typical host Bird flu Dog flu Horse flu Human flu Swine flu
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