Viruses (Science Foundations)

139 Pages·2011·5.836 MB·English

by  Phill Jones

s c i e n c e
f o u n d a t i o n s
Viruses
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SCIENCE FOUNDATIONS
Artificial Intelligence
Atomic Structure
The Big Bang
Cell Theory
Electricity and Magnetism
Evolution
The Expanding Universe
The Genetic Code
Germ Theory
Global Warming and Climate Change
Gravity
Heredity
Kingdoms of Life
Light and Sound
Matter and Energy
Natural Selection
Planetary Motion
Plate Tectonics
Quantum Theory
Radioactivity
Theory of Relativity
Vaccines
Viruses
The Water Cycle
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s c i e n c e
f o u n d at i o n s
Viruses
phill jones
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Science Foundations: Viruses
Copyright © 2012 by Infobase Learning
All rights reserved. No part of this book may be reproduced or utilized in any
form or by any means, electronic or mechanical, including photocopying, re-
cording, or by any information storage or retrieval systems, without permission
in writing from the publisher. For information, contact:
Chelsea House
An imprint of Infobase Learning
132 West 31st Street
New York, NY 10001
Library of Congress Cataloging-in-Publication Data
Jones, Phill.
Viruses / by Phill Jones.
p. cm. — (Science foundations)
Includes bibliographical references and index.
ISBN 978-1-60413-341-7 (hardcover)
ISBN 978-1-4381-3919-7 (e-book)
1. Viruses—Juvenile literature. 2. Virus diseases—Juvenile literature. I. Title.
QR365.J66 2011
579.2—dc22 2010047648
Chelsea House books are available at special discounts when purchased in
bulk quantities for businesses, associations, institutions, or sales promotions.
Please call our Special Sales Department in New York at [phone] or
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Text design by Kerry Casey
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Composition by EJB Publishing Services
Cover printed by Yurchak Printing, Landisville, Pa.
Book printed and bound by Yurchak Printing, Landisville, Pa.
Date printed: October 2011
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
Th is book is printed on acid-free paper.
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of publication. Because of the dynamic nature of the Web, some addresses and
links may have changed since publication and may no longer be valid.
SSFF VViirruusseess__dduummmmyy..iinndddd 44 1111//22//1111 22::2211::3355 PPMM
1 Introduction to Viruses 7
2 Cell Hosts for Viruses 16
3 The Life Cycle of Viruses 30
4 Viruses and Disease 44
5 Diagnosis of a Viral Disease 58
6 Treatment of Viral Disease 73
7 Prevention of Disease
with Vaccines 83
8 Viral Mutations and Emerging
Viruses 97
9 Challenges and Controversies 110
Glossary 118
Bibliography 121
Further Resources 130
Picture Credits 132
Index 133
About the Author 137
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Introduction to
Viruses
umans have tried to understand the nature of diseases for
H
thousands of years. Knowledge about a disease can inspire
methods for treating the illness and measures for avoiding the ill-
ness. For a long time, doctors thought that some unseen thing in
the air brought disease. The invention of the microscope revealed
the existence of bacteria. The presence of the tiny life forms sug-
gested a cause of diseases that spread from one person to another.
Then, scientists proposed that some infectious diseases were caused
by agents smaller than bacteria. These agents were too small for the
microscope. They were almost invisible.
Theories abouT Disease: From baD
air To Viruses
Doctors used to blame bad air for causing disease. Hippocrates, per-
haps the greatest doctor of his time, wrote a theory of disease in his
book, On Airs, Waters and Places (400 b.c.). In it, he suggested a
connection between disease and poorly drained land that emitted
foul air. Vapors, also called miasma, caused disease. Over the years,
others expanded the miasma theory of disease to include vapors giv-
en off by rotting bodies and vegetable matter. By the second century,

  Viruses
Figure 1.1 An 1832 cartoon called Sniffing for Cholera depicts the
miasma theory.
the foul-smelling breath of ill people had been added to the list of
disease-spreading vapors. The nineteenth century brought crowded
European cities with little or no sanitation. The cities had a lot of
bad air. The constant spread of many diseases among city dwellers
seemed to confirm the miasma theory.
Doctors and nurses urged that hospitals must be clean to purge
miasma from the buildings. They promoted cleanliness, good ven-
tilation, and the wide spacing of beds to separate ill patients. Engi-
neers paid attention to the miasma theory when they built closed
drainage and sewer systems. Along with garbage collection and pub-
lic baths, the fears of foul air led to improved public health. The mi-
asma theory sparked a sanitation revolution. Yet the revolt occurred
for the wrong reason. Infectious disease was spread by something
other than bad air.
After the invention of the microscope, some doctors suggest-
ed that small life forms might provide the answer to disease. In the
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introduction to Viruses  
eighteenth century, Scottish doctor Sir John Pringle wrote that mi-
crobes, rather than bad air, might explain how diseases are spread. In
1840, German physician Friedrich Gustav Jacob Henle argued that
infection by microbes was a major cause of disease. London doctor
Figure 1.2 London doctor John Snow traced the source of a cholera
outbreak in the Soho district of London, England, in 1854.
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