Quasispecies Concept And Implications For Virology

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.

Virus as Composition, Complexity, Quasispecies, Dynamics, and Biological Implications, Second Edition, explains the fundamental concepts surrounding viruses as complex populations during replication in infected hosts. Fundamental phenomena in virus behavior, such as adaptation to changing environments, capacity to produce disease, and the probability to be transmitted or respond to treatment all depend on virus population numbers. Concepts such as quasispecies dynamics, mutations rates, viral fitness, the effect of bottleneck events, population numbers in virus transmission and disease emergence, and new antiviral strategies are included. The book's main concepts are framed by recent observations on general virus diversity derived from metagenomic studies and current views on the origin and role of viruses in the evolution of the biosphere. Features current views on key steps in the origin of life and origins of viruses Includes examples relating ancestral features of viruses with their current adaptive capacity Explains complex phenomena in an organized and coherent fashion that is easy to comprehend and enjoyable to read Considers quasispecies as a framework to understand virus adaptability and disease processes

New viral diseases are emerging continuously. Viruses adapt to new environments at astounding rates. Genetic variability of viruses jeopardizes vaccine efficacy. For many viruses mutants resistant to antiviral agents or host immune responses arise readily, for example, with HIV and influenza. These variations are all of utmost importance for human and animal health as they have prevented us from controlling these epidemic pathogens. This book focuses on the mechanisms that viruses use to evolve, survive and cause disease in their hosts. Covering human, animal, plant and bacterial viruses, it provides both the basic foundations for the evolutionary dynamics of viruses and specific examples of emerging diseases. NEW - methods to establish relationships among viruses and the mechanisms that affect virus evolution UNIQUE - combines theoretical concepts in evolution with detailed analyses of the evolution of important virus groups SPECIFIC - Bacterial, plant, animal and human viruses are compared regarding their interation with their hosts

While the study of viral evolution has developed rapidly in the last 30 years, little attention has been directed toward linking the mechanisms of viral evolution to the epidemiological outcomes of these processes. This book intends to fill this gap by considering the patterns and processes of viral evolution at all its spatial and temporal scales.

A renaissance of virus research is taking centre stage in biology. Empirical data from the last decade indicate the important roles of viruses, both in the evolution of all life and as symbionts of host organisms. There is increasing evidence that all cellular life is colonized by exogenous and/or endogenous viruses in a non-lytic but persistent lifestyle. Viruses and viral parts form the most numerous genetic matter on this planet.

Completely revised and updated to reflect important advances in the field, Principles of Virology, Second Edition continues to fill the gap between simple introductory texts and very advanced reviews of major virus families, introducing upper–level undergraduates, graduate students, and medical students to all aspects of virology. The second edition retains all of the defining and much–praised features of the first edition, focusing on concepts and principles and presenting a comprehensive treatment from molecular biology to pathogenesis and infection control. Written in an engagingly readable style and generously illustrated with over 400 full–color illustrations, this approachable volume offers detailed examples that illustrate common principles, specific strategies adopted by different viruses to ensure their reproduction, and the current state of virology research. The book is divided into chapters that focus on specific topics rather than individual viruses, and allows the student to visualize common themes that cut across virus families, emphasizing the shared features of different viruses. Drawing on the extensive teaching experience of each of its distinguished authors, Principles of Virology illustrates why and how animal viruses are studied and demonstrates, using well–studied systems, how the knowledge gained from such model viruses can be used to study viral systems about which our knowledge is still quite limited. A thorough introduction to principles of viral pathogenesis, a broad view of viral evolution, a discussion of how viruses were discovered, and how the discipline of virology came to be are also provided. A variety of special boxes highlight key experiments, background material, caveats, and much more. The text focuses on concepts and principles and covers not only aspects of molecular biology, but also pathogenesis, evolution, emergence, and control, and will also be a valuable resource for practicing physicians and scientists. New in the Second Edition Completely revised pathogenesis chapters Pathogenicity Snapshots: an appendix highlighting teaching points for major viral diseases Expanded appendix on viral life cycles New chapter on viral genomes and coding strategies Detailed glossary Expanded references after each chapter new textboxes

This book provides a comprehensive look at the field of plant virus evolution. It is the first book ever published on the topic. Individual chapters, written by experts in the field, cover plant virus ecology, emerging viruses, plant viruses that integrate into the host genome, population biology, evolutionary mechanisms and appropriate methods for analysis. It covers RNA viruses, DNA viruses, pararetroviruses and viroids, and presents a number of thought-provoking ideas.