Continuous genetic variation and selection of virus subpopulations in the course of RNA virus replications are intimately related to viral disease mechanisms. The central topics of this volume are the origins of the quasispecies concept, and the implications of quasispecies dynamics for viral populations.

"Continuous genetic variation and selection of virus subpopulations in the course of RNA virus replications are intimately related to viral disease mechanisms. The central topics of this volume are the origins of the quasispecies concept, and the implications of quasispecies dynamics for viral populations. TOC:Preface.- What is a Quasispecies?.- Quasispecies in Changing Environments: Theoretical Aspects.- Viruses as Quasispecies: Biological Implications.- Virus Fitness: Concepts, Quantification and Application to HIV Population Dynamics.- Population Bottlenecks in Quasispecies Dynamics.- HIV Diversity and the Control of AIDS.- Evolution of Virulence in Picornaviruses.- Molecular Mechanisms of Poliovirus Variation and Evolution.- Viral Population Dynamics During Hepatitis C Virus Infections.- Evolutionary Influences in Arboviral Disease.- Arenavirus Diversity and Evolution: Quasispecies in vivo.- Mutant Clouds and Occupation of Sequence Space in Plant RNA Viruses.- Parvovirus Variation for Disease: a Difference with RNA Viruses?- Conceptual Transitions in our Understanding of RNA Virus Evolution: A Historical Perspective.- Subject Index."

What Is a Quasispecies?.- Quasispecies in Time-Dependent Environments.- Viruses as Quasispecies: Biological Implications.- Virus Fitness: Concept, Quantification, and Application to HIV Population Dynamics.- Population Bottlenecks in Quasispecies Dynamics.- Evolutionary Dynamics of HIV-1 and the Control of AIDS.- Evolution of Virulence in Picornaviruses.- Molecular Mechanisms of Poliovirus Variation and Evolution.- Hepatitis C Virus Population Dynamics During Infection.- Evolutionary Influences in Arboviral Disease.- Arenavirus Diversity and Evolution: Quasispecies In Vivo.- Mutant Clouds and Occupation of Sequence Space in Plant RNA Viruses.- Parvovirus Variation for Disease: A Difference with RNA Viruses?.- Transitions in Understanding of RNA Viruses: A Historical Perspective.