Attenuated pseudorabies virus having a deletion of at least a portion of a gene encoding an antigenic, nonessential protein, vaccine containing same and methods of identifying animals vaccinated with the vaccine

Abstract

Attenuated pseudorabies viruses are provided which comprise DNA including a sequence essential for replication of the attenuated pseudorabies virus, at least a portion of which is present in a sequence essential for replication of a naturally-occurring pseudorabies virus. The DNA encodes mRNAs which, in an animal infected with the attenuated pseudorabies virus, are translated into antigenic pseudorabies virus gene products which invoke in the infected animal an immunological response distinguishable from an immunological response invoked in an animal infected with a naturally-occurring pseudorabies virus. Also provided are vaccines which comprise the attenuated pseudorabies virus of the present invention and methods of immunizing animals against pesudorabies virus disease. The invention further provides a method for distinguishing an animal vaccinated with a vaccine of the present invention from an animal infected with a naturally-occuring pseudorabies virus.

Dependencies are inferred from the claim text.