Abstract: Disclosed herein is a vaccine which provides immunity to mammals from infection and/or disease caused by a lentivirus, such as equine infectious anemia virus, human immunodeficiency virus (HIV), feline immunodeficiency virus (FIV), bovine immunodeficiency virus (BIV) or simian immunodeficiency virus (SIV) said composition comprising a deletion in a gene that blocks replication of the virus in vivo. Preferably said composition encompasses at least one deletion in a lentivirus which provides protection from exposure to wild-type lentiviruses. It also encompasses a marker vaccine in which a foreign gene is inserted into the gene-deleted region, said inserted gene providing a diagnostic tool for use in vaccinated mammals. The scope of the invention encompasses an EIAV vaccine that allows equines to be safely vaccinated and protected from disease without converting to a seropositive status on the Coggin's Test or any other test wich measures p26.

Abstract: The invention relates to a method for infecting equines with an equine infectious anemia virus (EIAV) in order to reproduce a natural infection challenge model. More specifically, the invention provides a multiple low dose equine EIA challenge model comprising administering at least 1 median horse infective dose to an equine using an intravenous route of administration. It is preferable that the EIAV be administered on a repeated basis. The multiple low dose EIA challenge model described herein can be used for testing efficacy of vaccines, treatments and diagnostic tests.

Abstract: Disclosed herein is a vaccine which provides immunity to mammals from infection and/or disease caused by a lentivirus, such as equine infectious anemia virus, human immunodeficiency virus (HIV), feline immunodeficiency virus (FIV), bovine immunodeficiency virus (BIV) or simian immunodeficiency virus (SIV) said composition comprising a deletion in a gene that blocks replication of the virus in vivo. Said composition allows differentiation between vaccinated and non-vaccinated, but exposed, mammals and provides safety and immunity when administered as a vaccine to mammals. Preferably said composition encompasses at least one deletion in a lentivirus which allows mammals to be safely vaccinated and provides protection from exposure to wild-type lentiviruses. It also encompasses a marker vaccine in which a foreign gene is inserted into the gene-deleted region, said inserted gene providing a diagnostic tool for use in vaccinated mammals and, potentially, protection from infection from a foreign disease.

Abstract: Disclosed herein is a vaccine which provides immunity to mammals from infection and/or disease caused by a lentivirus, such as equine infectious anemia virus, human immunodeficiency virus (HIV), feline immunodeficiency virus (FIV), bovine immunodeficiency virus (BIV) or simian immunodeficiency virus (SIV) said composition comprising a deletion in a gene that blocks replication of the virus in vivo. Said composition allows differentiation between vaccinated and non-vaccinated, but exposed, mammals and provides safety and immunity when administered as a vaccine to mammals. Preferably said composition encompasses at least one deletion in a lentivirus which allows mammals to be safely vaccinated and provides protection from exposure to wild-type lentiviruses. It also encompasses a marker vaccine in which a foreign gene is inserted into the gene-deleted region, said inserted gene providing a diagnostic tool for use in vaccinated mammals and, potentially, protection from infection from a foreign disease.