RS> That does not mean that you necessarily get the population
RS> immune to the virus forever after tho. Like I say, it
RS> depends on what causes the survivors to survive.

RL> And virii have the common trait of mutating to enable survival.

Thats a bit garbled, you make it sound like the virus noticed
the problem and chooses to mutate. It doesnt work like that,
just like with everything else, the mutations just happen and
that strain may or may not have an advantage over the other strains.

In the case of the HIV strain which never sero converts,
it has clearly ended up with a mutation which is worse.

And there is a vast variation in mutation rates too. Some are extremely stable
like smallpox, some mutate at a hell of a rate like the common cold and flu.
@EOT:

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