From: Ian A. York
Newsgroups: misc.kids.health,sci.med
Subject: Re: Smallpox and medical men (Merz)
Date: 4 Sep 2000 19:52:32 GMT

In article <39B3B6BC.F7EE39ED@lumbercartel.com>,
D. C. & M. V. Sessions <dcs@lumbercartel.com> wrote:
>John Scudamore wrote:
>>
>> I would like to know where vaccinia came from?
>
>It's an indigenous disease of cattle (cowpox).  A couple of

No, it's not.

Vaccinia and cowpox are different viruses; they're closely related, but
they're not the same.  Both are closely closely related to variola virus
(smallpox), and both confer protection to smallpox (and to other related
poxviruses, such as monkeypox) because of this close relationship.

Jenner's original vaccine was cowpox.  But somewhere between his vaccine
and modern virology, the virus became vaccinia.  The true host for
vaccinia is not known; it's entirely a virus of cultured cells (with some
exceptions; it has been known to escape, and, for example, buffalopox is
quite probably vaccinia that escaped from a vaccinated human and infected
a buffalo).

Ian
--
    Ian York   (iayork@panix.com)  <http://www.panix.com/~iayork/>
    "-but as he was a York, I am rather inclined to suppose him a
     very respectable Man." -Jane Austen, The History of England