Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!rutgers!clyde!cuae2!ihnp4!houxm!mtuxo!jasond
From: jasond@mtuxo.UUCP (j.demont)
Newsgroups: net.puzzle,sci.math,sci.med
Subject: Math of Diseases
Message-ID: <2188@mtuxo.UUCP>
Date: Thu, 30-Oct-86 10:35:06 EST
Article-I.D.: mtuxo.2188
Posted: Thu Oct 30 10:35:06 1986
Date-Received: Fri, 31-Oct-86 13:51:35 EST
Organization: AT&T Information Systems Labs, Holmdel NJ
Lines: 30
Xref: mnetor net.puzzle:1554 sci.math:86 sci.med:148

I have a question relating to the mathematics of modeling the spread of a
contagious disease throughout a population.  I recently read an article 
where an "expert" said that the number of AIDS victim will increase
exponentially *indefinitely*.

It appears to me that for any communicable disease, that while the number
of victims is much, much smaller than the total population, the growth
curve of the number of victims could approximate an exponential curve.
However I speculate that the true curve approximates a hysteresis that
asymtotically approaches the total number of the population.  My conjecture
is based (perhaps falsely) on the notion that as the number of people
with the disease increases, the chances of giving the disease to an
uninfected person decreases, but is partially offset by the fact that there
are more carriers avaiable to communicate it.  It appears that after a while
most of the carriers will be infecting other carriers.

I would like to model the spread of the disease before it is apparent that
anyone even has it.  Therefore I would like to add the constraints that it
is chronically contagious, non-fatal and in no way can be known or guarded
against.  I would prefer that this be a discussion on modeling and not on
the peculiarities of the spread of AIDS.

Does anyone in net-land have experience with such modeling or have any
other thoughts on the matter?

Thanks,
Jason De Mont
AT&T
Lincroft, New Jersey
ihnp4!mtuxo!jasond