New technology for improved vaccine safety and efficacy

Nearly all of the 2000 vaccines presently licensed by the US Department of Agriculture for veterinary use in the United States are conventional vaccin es containing either killed or modified live whole bacteria or viruses. Rec ent advances in molecular biology, immunology, microbiology, and genetics a nd in understanding microbial pathogenesis have led to the development of a wide variety of new approaches for developing safer and more effective vac cines. This article briefly describes these new technologies and their pote ntial advantages and disadvantages as compared with conventional killed and modified live vaccines.