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Before we can conceive solutions to a problem, we need to accurately identify the source(s) of said problem. Rather than a one-way street where doctors simply unnecessarily prescribe too many antibiotics and the rest of us just haplessly consume them, 3 C’s, namely, culture, convenience, cost explain why we overuse antibiotics even though it’s undeniably counterproductive, for us, for our future and for the future of untold life forms on this planet. No one gets to wag a finger at others on this issue. All of human society is complicit in creating or enabling the culture of antibiotic over-usage.

Our culture actively enables, even encourages, excessive antimicrobial use
First, the cultural norm that ‘germs‘ are bad and need to be eliminated from our bodies, our lives and our environment. Why do ads proudly extol cleaners, wipes, sprays and lotions that eliminate 99.9% of germs? Because we, the consumers of such ads, tacitly agree that ‘germs‘ are bad and need to be eliminated from our lives. The prescribing and consuming of vast amounts of antibiotics occurs not in a vacuum but in thrall to a cultural construct of microbe-as-our-mortal-enemy that’s prevailed since the late 19th century when Koch and Pasteur discovered them in the context of human diseases. An absurdly wrong-headed notion of course but substantial numbers among us continue to believe it, and all because of that historical accident of how microbes were discovered. It’ll take time, maybe even generational time for the concept of human as human-microbe ecosystem to percolate through to society at large. Only then will the cultural norm shift to microbe as not our enemy. The distinction is nuanced but critical. Some, not all, microbes are pathogenic.

Our short-sighted focus on convenience and cost enables, even encourages, excessive antimicrobial use. How? Simple. We insist on abundant and cheap meat consumption.
Second, human antibiotic use is easily dwarfed by the scale of antibiotic use in industrial livestock agriculture.

Until fairly recently in recent human history, meat eating was by and large a luxury, typically consumed infrequently such as once a week, say the traditional Sunday post-church supper in pre-20th century USA. If meat-eaters, especially meat-eaters descended from meat-eaters cared to reminisce on familial practices, they would invariably reach an inflection point in their recent past prior to which meat was a luxury, a relatively rare treat for most humans.

Fast forward to today and in industrialized nations, frequent and copious meat eating is the norm. In fact meat eating is now a luxury for only a relatively tiny, decidedly marginalized and impoverished fraction of the population. In the US, for example, meat and fast food are mostly synonymous, and fast food joints are the mainstay of strip malls permeating the American landscape in superfluous abundance like dandelion seeds in fallow fields. Fast food in turn is economically cheap food, affordable by all but the poorest. Unsustainable at best, the deep-rooted and vexing problem is that it’s also eminently desirable in the popular imagination. Thus, such decidedly odious cultural practices as cheap and copious meat-eating end up becoming the norm. For e.g., recently China has even overtaken the rest in total meat production and consumption rates. Over the century or so as this tidal wave of cultural change set in, meat supplies grew, not modestly, but decidedly exponentially. How could this happen and so rapidly? How did meat become so abundant so suddenly? Widespread refrigeration and refrigerated transport? Certainly helped in making meat widely available but they couldn’t create over-abundant amounts of meat in the first place. Industrialization of livestock or industrial food animal production (IFAP) in CAFO (Confined Animal Feeding Operations) needed something else to spark over-abundant meat yields.

Antimicrobial Growth Promotion (AGP) in Industrial Food Animal Production (IFAP) is far and away the largest use of antibiotics
As food animal production rapidly switched from the pre-industrial pastoral mode to IFAP, especially CAFO, exponentially increased meat yields couldn’t happen without AGP. AGP what? AGP as in Antimicrobial Growth Promotion

  • As seems the norm in science, discovered by accident, still not understood, AGP is a poster child of decidedly mindless commercial exploitation.
  • World War II was a time of widespread protein shortage, even in the US.
  • Soy and corn were the mainstay for livestock. Such diets lacked essential B vitamins.
  • Looking for a cheap vitamin B12 source, scientists at Lederle Laboratories found that Streptomyces aureofaciens cultures used for producing chlortetracycline (Aureomycin) were as effective as animal liver extracts in enhancing vitamin B12-deficient chickens (1). Turned out the effect came from the antibiotic.
    • Pure aureomycin, penicillin and streptomycin enhanced chicken and pig growth (1, 2).
    • Turns out sub-therapeutic antibiotic treatments mysteriously accelerated livestock growth.
    • Less feed costs, less time to market. The economic rationale wrote itself.
    • Flurry of patents followed, and AGP became firmly ensconced in the IFAP system.
  • AGP in IFAP by far dwarfs human consumption of antibiotics, by at least ~4X conservatively (see figures below from 3).
  • China leads world usage of antibiotics by leaps and bounds (see figure below from 3).
  • Another mystery? Only anti-bacterials, not anti-fungals or anti-virals, produced this magic rapid weight gain effect.
  • Rapid weight gain, not treatment of bacterial illness, drives humungous antibiotic use in farm animals. In other words, impetus for AGP is economic, not medical.

 

  • Of course, no surprise that AGP in IFAP inevitably leads to bacterial antibiotic resistance in humans.
  • First reported in 1976 (4), steady avalanche of studies shows agricultural antibiotic use contributes to widespread bacterial resistance (see figure from 5 below for a recent example from Spain).
  • In fact, in 2002 an entire issue of the scientific journal, Clinical Infectious Diseases, focused on the link between prophylactic antibiotic use in CAFO and generalized antibiotic resistance in bacteria (6).


From antibiotics used in AGP for IFAP is a short step to well their presence everywhere (see figure below from 7).
1. Antibiotic-resistant bacteria colonize and grow

  • in animals.
  • on surfaces.
  • in manure.
  • and are carried beyond by flies, rats, wild birds.

2. Airborne pathogens from IFAP are spread by

  • Ventilation Fans.
  • Decomposing manure.

3. IFAP workers have

  • Higher rates of respiratory illness.
  • Higher rates of psychological distress.
  • Colonized by antibiotic-resistant bacteria.
  • Which are potentially transmissible to their communities.

4. IFAP waste is usually spread on agricultural lands

  • Includes antibiotics, excreted hormones, heavy metals.
  • Spreads into environment through ground and surface waters.

Horizontal gene transfer further spreads antibiotic-resistant genes far beyond IFAP, microbe-to-microbe all through the environment.

 


Meta-analysis of 33 studies on community exposure to IFAP (see figure below from 7) shows that it’s associated with

  • Respiratory problems.
  • MRSA (Methicillin-resistant Staphylococcus aureus) colonization.
  • Q fever.
  • Stress.


A 2008 review in the Annual Reviews of Public Health (5) succinctly summarizes the grave risks that ensue from such widespread antibiotic use, risks to not just human health but to all of our ecosystem.


Even more profound than antibiotics permeating all through our environment from massive IFAP use is the potential for their effect on every living cell.

  • Our mitochondria originated from bacteria themselves, proteobacteria to be precise, and recent studies show that many clinically approved antibiotics such as tetracyclines can potently inhibit mitochondrial ribosomes and protein synthesis (8).
  • Similar effects also seen in plant chloroplasts, another ancient bacterial remnant inside eukaryotic cells (8).
  • Thus, antibiotic influence of metabolism and function extends far beyond bacteria.
  • It’s one thing to take antibiotics to stave off an infection.
  • Quite another to be constantly exposed to them pervasively through our environment.
  • But that’s the largely invisible price for our mindless insistence on cheap and abundant meat.


So what can be done to reduce such excessive antibiotic use? What can WHO/UN do? Rather can they do something, anything?

Small countries first, followed by the EU as a whole led the way in banning AGP in IFAP

  • Denmark banned AGP, i.e., non-therapeutic antibiotics in farm animals followed by a complete EU ban by 2006.
  • Unfortunately, this led to increased therapeutic antibiotic use in livestock. Obviously some other way was needed.
  • In the Netherlands, a unique confluence of government policies, public pressure and voluntary private sector participation reduced all antibiotic use in IFAP by >50% in just 5 years (see figures below from 9).
  • While this is heartening, there is no simple formula or blueprint to disseminate this practice to other countries.
  • Rather, each country will likely evolve its own unique path to AGP-free farming.
  • Maybe it will even take an epidemic or two or three.

 

 


These government and public pressure-driven policy changes drive the obvious question.

  • If AGP drove accelerated weight gain which in turn engendered lower feed costs and less time to market, how could cheap and abundant meat production be sustained when AGP’s removed?
  • Turns out, the mystery of the AGP effect is not so mysterious after all.
  • AGP’s rendered superfluous when food animals are housed cleanly with diligent attention paid to their hygiene.
  • Analysis of data generated by a commercial chicken supplier itself (a US company called Perdue) showed this to be the case (5, 10, 11, 12).
  • So AGP wasn’t driven by just simple economic sense. Sheer sloth plays a role. As well disdain as in disdain for the very life forms being raised in the billions for food.


Bottomline, these data serve to highlight several knotty and distasteful conundrums.

  • One, they illuminate the extensive degree to which science remains subservient to culture.
  • Two, out of sight, out of mind. Billions of animals forcibly raised in CAFO is the invisible iceberg sustaining current sky-rocketing meat consumption levels. Sustaining? That’s at the very least obscenely funny because there’s nothing sustainable about the IFAP system.
  • And certainly nothing healthy about antibiotic use in IFAP. But hey, at least the meat’s cheap and convenient.


With such equations firmly ensconced in our societies, we cannot expect logic and reason to prevail. Even the most persuasive rational arguments are likely to fail because we time and again demonstrate Pavlovian preference for convenience and cost. The Guardian newspaper recently wrote that Industrial farming is one of the worst crimes in history. One of the worst? Hardly does justice. The worst? Certainly. Even more so given the astronomical and utterly atrocious degree of global food wastage. Estimates suggest that a third to a half of all world food production is simply wasted (rots/thrown away) (*).

Major recent government reports that draw a line in the sand, or at least attempt to do so, against the practice of AGP in IFAP include those by the European Food Safety Authority (EFSA), the Union of Concerned Scientists, the US Institute of Medicine published by the National Academies Press, and the US FDA (Food and Drug Administration) and USDA (the US Department of Agriculture).
EFSA reports:
Page on efsa.europa.eu
Page on efsa.europa.eu
Union of Concerned Scientists:
Page on ucsusa.org
US Institute of Medicine (IOM) reports published by the National Academies Press:
Reading: Microbial Threats to Health: Emergence, Detection, and Response
Reading: Antibiotic Resistance: Implications for Global Health and Novel Intervention Strategies: Workshop Summary
FDA’s 2012 Guidance document on use of antibiotics in livestock agriculture:
Page on fda.gov
USDA’s 2009 report:
Page on usda.gov

Bibliography

  1. Jukes, T. H. “The history of the” antibiotic growth effect”.” Federation proceedings. Vol. 36. No. 11. 1977.
  2. Luecke, R. W., et al. “The growth promoting effects of various antibiotics on pigs.” Journal of animal science 10.2 (1951): 538-542.
  3. Wang, Xu, et al. “Antibiotic use and abuse: A threat to mitochondria and chloroplasts with impact on research, health, and environment.” BioEssays 37.10 (2015): 1045-1053. Page on wiley.com
  4. Levy, Stuart B., George B. FitzGerald, and Ann B. Macone. “Changes in intestinal flora of farm personnel after introduction of a tetracycline-supplemented feed on a farm.” New England Journal of Medicine 295.11 (1976): 583-588.
  5. Silbergeld, Ellen K., Jay Graham, and Lance B. Price. “Industrial food animal production, antimicrobial resistance, and human health.” Annu. Rev. Public Health 29 (2008): 151-169. http://www.researchgate.net/prof…
  6. Clinical Infectious Diseases, Volume 34 Supplement 3 June 1, 2002  Table of Contents
  7. Casey, Joan A., et al. “Industrial Food Animal Production and Community Health.” Current environmental health reports 2.3 (2015): 259-271. Page on researchgate.net
  8. Wang, Xu, et al. “Antibiotic use and abuse: A threat to mitochondria and chloroplasts with impact on research, health, and environment.” BioEssays 37.10 (2015): 1045-1053. Page on wiley.com
  9. Speksnijder, D. C., et al. “Reduction of veterinary antimicrobial use in the Netherlands. the Dutch success model.” Zoonoses and public health 62.s1 (2015): 79-87. Page on wiley.com
  10. Engster, H. M., D. Marvil, and B. Stewart-Brown. “The effect of withdrawing growth promoting antibiotics from broiler chickens: a long-term commercial industry study.” The Journal of Applied Poultry Research 11.4 (2002): 431-436. Page on oxfordjournals.org
  11. Graham, Jay P., John J. Boland, and Ellen Silbergeld. “Growth promoting antibiotics in food animal production: an economic analysis.” Public health reports 122.1 (2007): 79. Page on nih.gov
  12. Miller, Gay Y., et al. “Productivity and economic effects of antibiotics used for growth promotion in US pork production.” Journal of agricultural and applied economics 35.03 (2003): 469-482. http://ageconsearch.umn.edu/bits…


* Tirumalai Kamala’s answer to How can a physicist, mathematician, or computational scientist get involved with solving world hunger?

https://www.quora.com/If-we-know-that-overusing-antibiotics-will-cause-resistant-bacteria-why-do-we-still-give-out-so-much-of-it-Especially-in-some-parts-of-the-world/answer/Tirumalai-Kamala

 

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