[extropy-chat] Game theory of common cold

[Robert J. Bradbury]

On Mon, 19 Jan 2004, Rafal Smigrodzki wrote:

> Assume that
> the source of new versions of the virus, frequently China, keeps on churning
> our new viruses yearly, and there is some accumulation of the viruses in
> various reservoirs (e.g. networks with slowly spreading, sporadic infection
> among small, separate communities).

Rafal, are you sure about this?

I was taught that most "colds" are the result of rhinoviruses which
have over 100 different serotypes.  You become immune to an individual
serotype after being infected but if you only have 1 cold/yr it takes
you 100 years to develop immunity to all of them.  I ran into this
problem when I started going to Russia -- almost every time I went
I would end up with a cold (probably due to different serotypes
from the U.S.) -- but after a few years I stopped catching colds
(presumably due to accumulated immunity.  In fact its been years
since I recall having a serious cold since I'm probably immune to
the most common U.S. and Russian serotypes.

[This characteristic makes me wonder why one just doesn't expose
a young person to all 100 serotypes at the same time at a young
age and be done with it.  This approach is being taken with
vaccinations against the cancer causing types of pappiloma viruses.]

If Anders model is going to be accurate and we are talking only
about rhinoviruses I think one has to take into account the 100+
serotypes as well as the advantages of accumulating local population
immunity.  To do it accurately you have to know the number of
serotypes circulating within relatively "isolated" populations
and the rate of introduction of new serotypes in our increasingly
interconnected world.

Now influenza on the other hand is a real problem because it is
a multi-segment genome that can recombine novel segments from
other species (birds, esp. Ducks, and pigs usually).  When
discussing China as a source of new viruses, it is generally
influenza that is discussed, not rhinoviruses.  Though at the
current time it appears that Vietnam is on the WHO watch list
for producing new viruses.  I haven't read whether they are
rhinoviruses, influenza or something completely new though.

Robert