
HIV evolving 'into milder form' - GotAnyMegadeth
http://m.bbc.co.uk/news/health-30254697
======
thanatosmin
Reading the original paper, they compare Botswana and S Africa and find a
correlation between seroprevalence and viral load. There is not good evidence
to suggest this is causative however--this may be, for example, that as you
get to higher frequencies of cases differently aged people are more likely to
be infected and show different viral loads. A direct causal link between these
two factors doesn't make a huge amount of sense, because (AFAIK) HIV is
thought to sample all viral sequences within each host (so population-level
selection should represent individual-level variation).

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ars
That's pretty typical for parasites (which include viruses).

Killing your host is never a good idea, the best parasites cause minimal
disruption to their host.

All animals and humans are infected with countless parasites, but you never
notice. For example
[https://en.wikipedia.org/wiki/Face_mite](https://en.wikipedia.org/wiki/Face_mite)
(don't scratch).

~~~
GotAnyMegadeth
Sometimes if the parasite moves from host to host as part of it's life cycle,
and this can include aiding the death of one host. An example of this is a
parasite that causes frogs to grow extra legs so that they are easier to catch
for birds. The parasite then transfers to the bird, where it can lay it's
eggs.

[http://phenomena.nationalgeographic.com/2013/02/13/a-flurry-...](http://phenomena.nationalgeographic.com/2013/02/13/a-flurry-
of-frog-legs/)

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nsajko
[http://www.davidbrin.com/givingplague.html](http://www.davidbrin.com/givingplague.html)
A very nice story of Brin based on the notion of a process of infectious
agents "watering down" over time.

~~~
chadgeidel
Thank you! I was _just_ going to ask for that story!

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BrainInAJar
"In theory, if we were to let HIV run its course then we would see a human
population emerge that was more resistant to the virus than we collectively
are today - HIV infection would eventually become almost harmless."

Because millions (or billions) of people would die, leaving only those with
resistance.

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pistle
> "Twenty years ago the time to Aids was 10 years, but in the last 10 years in
> Botswana that might have increased to 12.5 years, a sort of incremental
> change, but in the big picture that is a rapid change."

20 years ago, the ARV's and mixes weren't what they were 10 years ago and
awareness + access to therapy also changed. Therapy initiation guidelines
changed - which would directly impact time to AIDS.

Throw that statement away in relation to the meaning of the study results -
except if this statement is there, it raises a concern about bias or mistakes
in the study due to an insufficiently rigorous handling of the data and
contexts/meaning.

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guard-of-terra
I wonder if infecting a person with AIDS with milder form of HIV will make
them better.

~~~
ars
That would imply that HIV viruses compete with each other, and this
competition is able to suppress each other.

This is typical with bacteria, but I don't think it happens with viruses.

~~~
couradical
Sure it can - think of smallpox: the first smallpox "vaccine" was actually
inoculation with cowpox - a similar, but less virulent virus. The provoked
immune response rendered a smallpox infection less lethal, and provided a
measure of protection.

\-
[http://en.wikipedia.org/wiki/Smallpox_vaccine](http://en.wikipedia.org/wiki/Smallpox_vaccine)

~~~
ars
That's quite different, we are speaking of have two pathogens compete, not
about triggering an immune response.

If you took someone who is already infected with smallpox and gave them cowpox
it would not help.

You confused in what order the infections occur.

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ruairinewman
Surely this process means that HIV is just as capable of evolving into
something even more lethal over time, given the right environment? Given the
relatively closed environment of a country like North Korea (for example)
where diversity is restricted, its evolutionary path may take a different
route than that observed by the University of Oxford research team?

~~~
jowiar
Can random mutations make HIV more lethal? Sure. The argument here is that
lethality makes HIV "less fit" from an evolutionary standpoint, which makes
sense, as, given the means of transmission, killing the host isn't a
particularly useful thing for the virus to do.

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fenomas
As is so often the case, William Gibson came pretty close to predicting this:

[http://everything2.com/title/J.D.+Shapely](http://everything2.com/title/J.D.+Shapely)

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astralship
strikes me that human immune systems are working collaboratively in the case
of HIV

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billpg
What viruses "want" is to reproduce. Killing you is an unfortunate unplanned
side effect.

If only we could negotiate and agree to allow them to reproduce and not kill
us, we'd all get along much better.

~~~
cJ0th
That's an interesting thought. It's like they posses "artificial
intelligence", i.e. they behave like the famous paper clip maximizer.

~~~
snowwrestler
Obviously viruses are not intelligent and they don't "want" to reproduce.

However, they do reproduce, just like pretty much every other form of life.
The question of why life does that is closely related to the question of what
life _is_ and how it came to exist. Those are deep questions and we don't
really have a clue as to the answer right now. There's certainly nothing in
the fundamental physical laws of the universe, as we understand them today,
that seems to indicate or require the existence of life.

~~~
Justsignedup
What if life is just an accidental misshapen rock which spreads itself
changing constantly to adapt to ever hostile environments.

OMG What if we're the cancer of the universe, who is in itself a giant
amoeba!??!!?!?!?

deep thoughts, with jack handy

~~~
dredmorbius
Closer than you might think. Howard Odum in 1971 suggests that humans are
something of a decomposer, working on a backlog of accumulated energy and
mineral deposits:

 _Sometimes in half-seriousness we say that man may have been evolved by the
system as a mechanism to get the fossil fuels and other minerals back into
circulation. We hope he is pre-adapted for other roles after that._

From _Environment, Power, and Society_.

An analog I use is to opportunistic benthic whale fall communities. The emerge
and develop rapidly. They do not sustain.

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kornakiewicz
Good guy HIV.

