antibioticsbooks

Antiviral Drugs
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Introduction to Antiviral Drugs
The term virus has interesting meanings in popular
culture: it is commonly used to describe something
that has or can spread quickly from person
to person, such as a computer virus or a “viral”
video, a video that gains quick popularity through
Internet or e-mail sharing. This usage represents
a basic understanding of the high transmissibility
of many respiratory viruses, such as influenza
and the rhinoviruses that cause the common cold.
However, many less-understood viruses, particularly
those that cause chronic disease, can be
confusing.
The world of viruses is very different from that
of prokaryotes and eukaryotes. Viruses are dependent
on cells to replicate and cannot perpetuate
without them. They are considerably smaller than
eukaryotes and even much smaller than most
prokaryotes, though they vary widely in size (see
Figure 1–2). They are relatively simple organisms
compared with prokaryotes or eukaryotes, but they
outnumber all life forms on earth. Scientists have
debated for many years about whether viruses are
life forms or not, and no clear consensus yet exists.