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From: dyer@spdcc.UUCP (Steve Dyer)
Newsgroups: net.med
Subject: Re: Re: Where are drugs (antibiotics) legal?
Message-ID: <27@spdcc.UUCP>
Date: Tue, 4-Mar-86 22:36:11 EST
Article-I.D.: spdcc.27
Posted: Tue Mar  4 22:36:11 1986
Date-Received: Fri, 7-Mar-86 05:48:17 EST
References: <156@proper.UUCP> <12057@ucbvax.BERKELEY.EDU> <915@felix.UUCP> <22@spdcc.UUCP> <2292@aecom.UUCP> <700@osiris.UUCP>
Reply-To: dyer@spdcc.UUCP (Steve Dyer)
Organization: S.P. Dyer Computer Comsulting, Cambridge MA
Lines: 21
Keywords: chicken feed

With the small amounts of antibiotics found in meat and poultry when
they are used as a feed supplement, I'd think the concern about exposure
to trace amounts of the chemicals is more aesthetically than clinically
important.  Not that having any of that stuff in your food is *good*,
but the clear and present danger comes from the development of resistant
strains of bacteria which can also infect humans, as in the case of an
outbreak of Salmonella food poisoning which was traced to an antibiotic-
resistant strain found in farm animals.  What's worse, the genes for
antibiotic resistance are found on extra-nuclear packets of DNA called
plasmids, many of which can be passed via conjugation (single-cell sex,
if you will) to other non-resistant bacteria, when then also become
resistant without every having been exposed to the original drug.
Finally, it looks as if these plasmids tend to remain in a bacterial
population once established; that is, there are clear evolutionary
pressures for the ability to receive a plasmid coding for resistance,
but little genetic overhead in continuing to carry it.

-- 
Steve Dyer
dyer@harvard.HARVARD.EDU
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