Basic Virology

Martinez J. Hewlett, David Camerini, David C. Bloom

• Editore: Wiley-Blackwell
• Anno: 2021
• ISBN:
  9781119314066
• Edizione: 4
• Argomento: Biological Sciences
• Categoria: Microbiology

The foundational textbook on the study of virology

Basic Virology, 4 th Edition cements this series' position as the leading introductory virology textbook in the world. It's easily read style, outstanding figures, and comprehensive coverage of fundamental topics in virology all account for its immense popularity.

This undergraduate-accessible book covers all the foundational topics in virology, including:

• The basics of virology
• Virological techniques
• Molecular biology
• Pathogenesis of human viral disease

The 4 th edition includes new information on the SARS, MERS and COVID-19 coronaviruses, hepatitis C virus, influenza virus, as well as HIV and Ebola. New virological techniques including bioinformatics and advances in viral therapies for human disease are also explored in-depth. The book also includes entirely new sections on metapneumoviruses, dengue virus, and the chikungunya virus.

PART I
Virology and Viral Disease

• Introduction – The Impact of Viruses on Our View of Life
  • The Science of Virology
• An Outline of Virus Replication and Viral Pathogenesis
  • Virus Replication
  • Pathogenesis of Viral Infection
• Virus Disease in Populations and Individual Animals
  • The Nature of Virus Reservoirs
  • Viruses in Populations
  • Animal Models to Study Viral Pathogenesis
• Patterns of Some Viral Diseases of Humans
  • The Dynamics of HUMAN–VIRUS Interactions
  • Patterns of Specific Viral Diseases of Humans
  • Some Viral Infections Targeting Specific Organ Systems
• Problems for Part I
• Additional Reading for Part I

CHAPTER 1
Introduction – The Impact of Viruses on Our View of Life

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• THE SCIENCE OF VIROLOGY
• The effect of virus infections on the host organism and populations – viral pathogenesis, virulence, and epidemiology
• The interaction between viruses and their hosts
• The history of virology
• Examples of the impact of viral disease on human history
• Examples of the evolutionary impact of the virus–host interaction
• The origin of viruses
• Viruses have a constructive as well as destructive impact on society
• Viruses are not the smallest self‐replicating pathogens
• QUESTIONS FOR CHAPTER 1

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THE SCIENCE OF VIROLOGY

The study of viruses has historically provided and continues to provide the basis for much of our most fundamental understanding of modern biology, genetics, and medicine. Virology has had an impact on the study of biological macromolecules, processes of cellular gene expression, mechanisms for generating genetic diversity, processes involved in the control of cell growth and development, aspects of molecular evolution, the mechanism of disease and response of the host to it, and the spread of disease in populations.

In essence, viruses are collections of genetic information directed toward one end: their own replication. They are the ultimate and prototypical example of “selfish genes.” The viral genome contains the “blueprints” for virus replication enciphered in the genetic code, and must be decoded by the molecular machinery of the cell that it infects to gain this end. Viruses are thus obligate intracellular parasites dependent on the metabolic and genetic functions of living cells.

Given the essential simplicity of virus organization – a genome containing genes dedicated to self‐replication surrounded by a protective protein shell – it has been argued that viruses are nonliving collections of biochemicals whose functions are derivative and separable from the cell. Yet this generalization does not stand up to the increasingly detailed information accumulating describing the nature of viral genes, the role of viral infections in evolutionary change, and the evolution of cellular function. A view of viruses as constituting a major subdivision of the biosphere, as ancient as and fully interactive and integrated with the three great branches of cellular life, becomes more strongly established with each investigational advance.

It is a major problem in the study of biology at a detailed molecular and functional level that almost no generalization is sacred, and the concept of viruses as simple parasitic collections of genes functioning to replicate themselves at the expense of the cell they attack does not hold up. Many generalizations will be made in the survey of the world of viruses introduced in this book; most if not all will be ultimately classified as being useful, but unreliable, tools for the full understanding and organization of information.

Even the size range of viral genomes, generalized to range from one or two genes to a few hundred at most (significantly less than those contained in the simplest free‐living cells), cannot be supported by a close analysis of data. While it is true that the vast majority of viruses studied range in size from smaller than the smallest organelle to just smaller than the simplest cells capable of energy metabolism and protein synthesis, the mycoplasma and simple unicellular algae, the recently discovered mimivirus (distantly related to poxviruses such as smallpox or variola) contains nearly 1000 genes and is significantly larger than the smallest cells. With such caveats in mind, it is still appropriate to note that despite their limited size, viruses have evolved and appropriated a means of propagation and replication that ensures their survival in free‐living organisms that are generally between 10 and 10 000 000 times their size and genetic complexity.

The effect of virus infections on the host organism and populations – viral pathogenesis, virulence, and epidemiology

Since a major motivating factor for the study of virology is that viruses cause disease of varying levels of severity in human populations and in the populations of plants and animals that support such populations, it is not particularly surprising that virus infections have historically been considered episodic interruptions of the wellbeing of a normally healthy host. This view was supported in some of the earliest studies on bacterial viruses, which were seen to cause the destruction of the host cell and general disruption of healthy, growing populations of the host bacteria. Despite this, it was seen with another type of bacterial virus that a persistent, lysogenic infection could ensue in the host population. In this case, stress to ...