Dennis Szeszko
Mon, 20 Nov 2006 10:06:13 PST
> The same is true for human viral infections,m
> > i.e., chickenpox, one "gets over "  the disease, but it can recur years
> > later in the form of "shingles".  Which is very painful and can be
> lethal.

Actually, this is a different mechanism.  The  Varicella-Zoster virus that
causes chickenpox and shingles often retreats to ganglia bundles near the
spinal cord after the body mounts an impressive immune response to fight off
the childhood chickenpox infection.  While the virus is in the nerves it
cannot be "seen" nor attacked by the immune system because the human immune
system is designed not to interfere with the nervous system.  For some
reason, possibly as a result of an immuno-compromised state or stress, the
virus reactivates later on and spreads down the nerve pathways.  In short,
the chickenpox virus is never truly eliminated from the body but only kept
in check.  (The same thing occurs with "cold sores" and concomitant herpes

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