The 1872 epizootic.
D000818:Animals; D004196:Disease Outbreaks / Q000266:history / Q000662:veterinary*; D049672:History, 19th Century; D006734:Horse Diseases / Q000266:history*; D006736:Horses; D007629:Kentucky; D009976:Orthomyxoviridae Infections / Q000266:history / Q000662:veterinary*