Abstract: This invention relates to a method and resulting temperature-sensitive (ts) reassortant virus produced by modifying wild-type equine influenza viruses by utilizing mutagenized human influenza viruses possessing ts lesions and shut off temperatures in the area of 37.degree.-39.degree. C., preferably 37.degree.-38.degree. C. When utilized as a vaccine for equines, these temperature-sensitive recombinant viruses have the facility to develop only mild symptoms while producing protection against infectious equine influenzal disease.

Abstract: Method and composition for the diagnosis of equine infectious anemia virus infection in animals involving the use of an immunodiffusion reaction plate, wherein separate wells in the reaction plate contains an antigen associated with the virus, an antiserum to the virus and the serum of the suspect animal. A positive response is indicated by a precipitin line of identity between the antigen well, antiserum well and the suspect serum well. Also disclosed is a novel antigen composition and a method for obtaining the same which is particularly suited in a diagnostic test for equine infectious anemia in animals.