Some thoughts in response to Russ Bulluck's wonderful thinking on
soil-borne enteric (gut-residing) bacteria that he's been sharing
lately. I drafted most of this in September, but wanted to let it sit
awhile.
Some time ago there was a thread of discussion here on SANET about
the effects of antibiotics in livestock and poultry operations.
Epidemiologists and other folks with a systems perspective on health
and disease have been pointing out for some years now that the use of
antibiotics in humans and animals is decreasingly effective for what
these drugs were intended for: to fight/control disease. And that
this poses some unprecedented specters for large organisms like
humans.
Antibiotics wipe out a broad range of flora and fauna in the bodies
of the organisms that are dosed with them. Theoretically, in wiping
out those microbes, the target one also falls victim. Some
antibiotics are more targeted than others...and some are quite
wide-spectrum.
When you wipe out any life form, there will be some survivors. They
survive by virtue of having resistance to whatever it was that wiped
out their amigos. There's no mystery in this: life is an ancient
thing on this planet--the fossil record shows the first prokaryotes
appearing 3.8 billion years ago. And today's bacterial microbes are
just that--one-celled packets of DNA, no nucleus. Whose genes encode
a vast history of trial and error. Bacteria have spent nearly all
their history working on that DNA. Rather than, like larger
creatures, devoting so much energy and intelligence and code to
making different nifty tools like beaks or the anglerfish's worm or
the chameleon's tongue, or variations in color, or size.
When the survivors of a wipe-out event reproduce, they pass along
that survivability to whatever killed their fellows--and they even
engineer new types. So in the case of bacterial resistance to
antibiotics, when they next come into contact with a host organism,
they're likely to be even more devastating. Because they are
resistant not only to the organism's natural defenses (which they
challenged to begin with, and survived) but to these engineered drugs.
Not to mention that bacteria go through many more generations than
their hosts in the same amount of time. I believe it was Russ who
pointed out that some microorganisms cycle through a new generation
every 20 minutes. It takes us 20 years. So when there are selection
pressures, who's going to adapt more quickly? Not on the individual
basis, mind you--on the species basis. (Only humans apparently have
the arrogance to worry about themselves on an individual basis, never
mind to try to change species to suit their individual needs.)
This raises the stakes rapidly from the perspective of us macrobes,
who are trying to stay a few inches ahead of the microbes and other
small beings whose era this is. What starts out as an effort to
control disease (antibiotics) turns out to be an experiment in
natural selection--one that encourages these microbes to evolve more
quickly and get a lot smarter, fast. The pressure is then on the drug
engineers to engineer new drugs...and everybody from CDC and WHO to
your next door neighbor is quickly figuring out that that's not a
race we can win. We may be smart primates with opposible thumbs, but
the rules of life were laid down long before the first flint knife
was knapped.
Unless, of course, you live in Kansas, where people can choose to
ignore observable biological realities because they're just too hard
to think about, and their consequences are at odds with a very recent
story about how humans were created to have dominion on a planet
where they are such newcomers. Reminds me of the technoyuppies who
are gentrifying the Mission here; to hear them tell it, they and
their gods (computers) invented the place. Gosh, Toto, let's not
think about the fact that god created cyanobacteria so long before
bipedal primates showed up; it's SOOO depressing. (Remember what
happened to Giordano Bruno for claiming that the universe didn't
revolve around the earth? But I digress.)
The antibiotic resistance issue parallels the model of pesticide use
that industrial ag has given us, by the way. That's another losing
game not, as some would suggest, because we in sustag have the wrong
politics or foofy spirituality, but because from a biological point
of view, technicians are not smart enough to outwit How Life Works.
Though our Gene Jockeys with their DNA six-shooters and our spray n
pray boys think they are. However, all they can do is develop new
"technologies" with very impressive initial effects. Like the
knockdown effect of DDT. That quickly dissolve, or have unexpected
events because we don't fully understand the context in which the
effects unfold.
Back to antibiotics. The widespread use of antibiotics pretty much
guarantees that the "leading edge" of dangerous microbes will expand
rapidly in the direction of Appallingly Virulent. Antibiotics
accelerate natural selection by constantly stressing the microbial
community, encouraging microbial genomes to express and evolve latent
resistances.
Antibiotics also wipe out the complex balances of microbial activity
that for billions of years have held evolution in check for any given
species/strain. What epidemiologists are increasingly warning us
about is that, in our zeal for killing off Microbe X, we've flushed
out whole microbial ecosystems that for billions of years have
co-evolved with that microbe.
If any people in society right now have lessons to teach about that,
it's us in sustainable and organic ag, on the basis of our having
witnessed the failure and tragic farce of pesticides in the second
half of this century.
Entomologist Ken Raffa at UW-Madison (one of CIAS's early research
partners) once told me, and I paraphrase: "There's no need to nuke
insects to control their populations, but that's the approach we're
taught in ag. The fact is that insects hold on to the slippery slope
of survival by their fingernails. More research needs to focus on
dislodging their tenuous hold on that slope, rather than obliterating
them altogether. We've learned over and over that when you try to
wipe out a species, you in fact end up losing control tools--because
whatever you used to wipe them out won't be effective any longer with
the offspring of those who survived that tool. This is basic biology.
But too many researchers have this B-movie view of insects as these
vastly frightening, horribly powerful creatures that need to be
obliterated at any or all costs. The irony is, they *can* be, if we
upset the balance enough."
By comparison to insects (never mind humans), microbes are damnably
smart (adaptive, creative) creatures. THINK about this:
/Staphylococcus/ was 100 percent vulnerable to penicillin in the
early 50s; in 30 years, fewer than 10 percent of all clinical
/Staph./ cases could be cured with penicillin. By the early 90s,
vancomycin was seen as the only surefire killer of /Staph./, yet if I
remember correctly, the first documented death due to a
vancomycin-resistant /Staph./ infection occurred in New York City in
1998 (I'm taking that from memory; don't quote me on that).
How did /Staph./ do this? Danged microbes did their own genetic
engineering, and picked up a gene packet that defused the penicillin
bomb. The microbes who had this little innovation thrived despite
penicillin, passed along their trick to their offspring...voila.
New /Staph./ strains grow thousands of times faster, give off enzymes
that make penicillin-class antibiotics ineffective, and generate
potent T-cell stimulators that cause not only hyperexcitation of the
human immune system...but eventual collapse of it (as in the case of
TSST-1, the strain that causes Toxic Shock Syndrome).
Did I mention that penicillin-class antibiotics--like most
antibiotics--are derived from organisms found naturally in the soil?
The actinomycetes that Chuck asked about (I'm spinning a response to
his question separately). Yep, and /Staph./ originate in the soil as
well. So why would it come as a surprise that critters that have been
co-evolving with certain selection pressures for billions of years
are really crafty in devising ways to outfox them? Or that they can
devise these ways in just a few decades?
We're tinkering with the life of soil, in all of this--the soil we
come out of, and return to, has a vast life-web of its own, and has
fought battles within itself that we know nothing of. But instead of
building host resistance to microbial threats on human health, we
focus on upping the ante by developing more and more potent
antibiotics. Which in turn lead to the development of more and more
potent microbial threats. Or by telling ourselves we can someday
"read" the "genetic code" and understand it.
This looks, to me, like a game we can't expect to come out ahead on,
never mind win.
So is it accidental that some of these hugely virulent microbes--like
/E. coli/ 0157:H7 and /Salmonella typhimurium/ DT104--are suddenly
turning up? Which of them can live in the soil, and for how long? We
know that /S. typhimurium/ DT 104 can be passed along thru the feces
of many different animals...what other unwitting experiments in
genetic engineering (the selection-pressure type, as well as the
gene-splicing type)--brought to you by the same pharmaceutical
industry that's consolidating its control of GMOs--are passing
through the innards of critters in your average factory farm?
When are these people who are so clever with their laboratory
techniques going to go back to the drawing board, and learn a bit
about Life on Earth 101: How Things Work Here? Will we in sustainable
ag do the same?
It doesn't appear that these answers are easy to get at. I spoze
someone could trumpet the need for More Research. That's one of those
suggestions that is rarely wrong...but likewise rarely able to keep
up with the costs of the technology that caused the problems in the
first place. Antibiotic resistance is a side-effect of antibiotic
use. Just like pesticide resistance is a side-effect of pesticide use.
Here we are, back at the Precautionary Principle.
My point is that, if we're doing these experiments in the gut of
livestock--exposing enteric microbes to such tough selection
pressures--is it far-fetched to imagine that Bossy might suddenly be
plopping out some pretty tough bacterial customers, like /E. coli/
0157:H7? And other players to be named later?
That brings me back to the issue of organics. I have strong doubts
that such new outbreaks can be blamed on organic farming. To begin
with, even if certified organic farmers ARE spreading raw manure on
their crops, which they aren't (though I'm sure that J. Random
Sensationalist Journalist or Dennis Avery could find an example or
two to the contrary, to make headlines with), it's going to be from
organically raised animals, not animals who've been hosts to these
unwitting and bizarre experiments in evolution and natural selection,
generation after generation.
Organically raised animals are likely to be animals with immune
systems (reminding me of how one of the first things that dairy
farmers report after one to three years in a management-intensive
grass-based system is that their animals "get healthy"), as well. I'd
like to see some research on whether this strain of /E. coli/ can get
a foothold in organisms whose immune systems are not compromsed. What
I've heard from the FDA about this and other "food poisoning" issues
is that it is PRECISELY among the immunocompromised that these
microbes' effects go from distressing to fatal. But instead of making
it an agenda to build immune system competence, the focus ends up
being on more potent antibiotics. From a compassion standpoint,
wholly understandable...but clearly at odds with life on earth.
The whole point of organics is to try to restore natural balance to
ecosystems, and to substitute management for control. It isn't just
about "clean food." Which leads me to conclude that, some day,
organics, as well as evolution, will be illegal in Kansas--for the
crime of daring to posit that the web of life on earth is more
complicated than described in the two conflicting versions of the
creation myth appearing in the book of Genesis.
Here is the World Health Organization's 1997 report on antibiotic use
in the food chain:
http://www.who.int/emc-documents/antimicrobial_resistance/whoemczoo974c.html
peace
misha
(PS--By the way, I adore the book of Genesis, but not nearly so much
as the chapter in Job, where--after he's sitting there howling for 37
chapters about how mean god is, and unfair life is, etc., on and
on--he says, "YEAH, and if god were here, I'd give him a piece of my
mind and tell him what I think and make him see things my way!" And
then, the story goes, the voice spake out of the whirlwind, "Job,
gird up your loins like a man, for I'll question you, and you'll
answer me." It is, for me, the funniest moment in the Old Testament.
You can just imagine the look on Job's face. Then god goes on to
wallop him about his arrogance, and the theme is loosely this: "Who
do you think you are, claiming to understand your fate and my nature,
when you don't even understand the most basic things about life on
this planet and how the cosmos works?" Really. Read it for yourself.
The litany of the mysteries of the earth, Job 38-41.)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Michele Gale-Sinex
Communications manager
Center for Integrated Ag Systems, UW-Madison
http://www.wisc.edu
UW voice mail: 608-262-8018
Home office: 415-504-6474 (504-MISH)
Home office fax: Same as above, phone first for enabling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I eat everything. If anything is there, I eat it. I presume it is
safe and good. --U.S. Secretary of Agriculture Dan Glickman
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