SECTION 1: Today's Live Attenuated Vaccines -- Live Vaccines and their Role in Modern Vaccinology -- Live Attenuated Vaccines: Influenza, Rotavirus and Varicella Zoster -- Classical Live Viral Vaccines -- SECTION 2: Genetically Attenuated Micro-Organisms as Vaccines -- Recombinant Live Vaccines to Protect Against the Severe Acute Respiratory Syndrome Coronavirus -- Live Attenuated Shigella Vaccines. Is encouraging good enough? -- New generation BCG vaccines -- SECTION 3: Manipulating Host-Pathogen Interactions to Make Vaccines -- Basic Science Paves the Way to Novel Safe and Effective Pestivirus Vaccines -- Live Attenuated Influenza Virus Vaccines: NS1 Truncation as an Approach to Virus Attenuation Approaches -- An Attenuated Herpes implex Virus 1 Live Virus Vaccine Candidate that is Replication Competent but Defective in Epithelial Cell to Cell and Neuronal Spread -- RSV Deletion Mutant - Innate Immunity -- Live Attenuated Cholera Vaccines: Flagella and Reactogenicity -- SECTION 4: New Types of Replicating Vaccines -- Replication-defective Herpes simplex Virus Mutant Strains as Genital Herpes Vaccines and Vaccine Vectors -- Nucleic Acid-Based Infectious and Pseudo-Infectious Flavivirus Vaccines -- Application of Cleavage Activation Mutants of Influenza Virus as Live Vaccines -- Alphavirus Particle-based Vaccine Vectors -- Recombinant, Chimeric, Live, Attenuated Vaccines against Flaviviruses and Alphaviruses. Technological advances, together with a better understanding of the molecular biology of infectious microorganisms, are creating exciting possibilities for a new generation of replicating vaccines. Historically, live vaccines have been either directly derived from a natural source or attenuated by empirical approaches using serial passages and host cell adaptation. Currently, we are witnessing a quantum leap in our technological capabilities to specifically modify the genetic make-up of viruses and bacteria, making it possible to generate improved live vaccines and to develop completely new types of replicating vaccines, such as vectored vaccines, single-round infectious vaccines and replicon vaccines. This book highlights some of the most exciting recent developments towards a new generation of replicating vaccines.