Antimicrobial Usage & Spread of Resistance -Reply

Steven Projan PROJANS at
Tue Jan 21 16:34:57 EST 1997

I've seen it written and said many times that the using antibiotics
for treating what may be a viral infection represents a missue of
antibiotics and is a major cause of antibiotic resistant bacteria.  

Indeed this could be true but before we accept this oft repeated
theory as fact, how about someone shows us some data?

1)  We can be fairly certain that the use of low doses of antibiotics
in animal feed can select for the emergence and dissemination of
resistant bacteria.  There is good data on this subject.

2)  We also can be pretty sure that certain patterns of hospital use
of antibiotics can select for mutliply resistant bacteria (like
vancomycin resistant enterococci).  Again lots of data on this issue
have been published.

But 3)  For the most part antibiotic resistance genes are usually not
found to arise in the U.S. but are "imported" with the initial
emergence of pathogenic, resistant strains arising elsewhere (like
methicllin resistant staphylococci and penicillin resistant
pneumococci).  This may be caused by even worse abuses abroad or
environmental factors abroad - like antibiotic use coupled with poor
sanitation and poor personal hygiene.

In fact community acquired infections from resistant bacteria,
although on the rise, are far rarer than hospital infections from
resistant bacteria - therefore one might well hypothesize that
resitance is spread into the community from hospitals and/or nursing
homes.  So what real impact is there from ex-hospital use in terms of
the emergence and spread of resistance?

And do we actually know how often antibiotics are prescribed for
viral infections?  And how many people with viral infections then go
on to contract a secondary bacterial infection (which an antibiotic
may therefore prevent)? And what if only 20% of such infections are
really bacterial - do we let those 20% suffering from bacterial
infections get sicker until we get the culture results?  Is that
smart practice?  Since when does the Hipocratic oath say "Do no

Sorry but before I can accept the premise that bad family doctors
writing antibiotic prescriptions for what may be a viral infection
cause antibiotic resistance all I can say is:

SHOW ME THE DATA!!!  And I don't mean The New York Times or that
semi-informed, hyperbolizing, plague of a tabloid journalist Laurie
Garrett, I mean good, solid peer reviewed, New England Journal of
Medicine-type data.

Steve Projan
Wyeth-Ayerst Research
(a big bad pharmaceutical company)

More information about the Microbio mailing list