Thursday, August 20, 2009

AVMA and the use of antibiotics in food animals

My professional association, the AVMA, has come out opposing the passage of H.R. 1549 and S. 619, the Preservation of Antibiotics for Medical Treatment Act (PAMTA). The bills aim to ban the use of certain antibiotics in large food animal production and finishing facilities, known as CAFOs (concentrated animal feeding operations). Within two years of enactment, the Preservation of Antibiotics for Medical Treatment Act (PAMTA) would require the Food and Drug Administration (FDA) to review the previous approvals for animal feed uses of seven classes of antibiotics that are important to human medicine. Any found to be associated with human antibiotic resistant bacteria will have their approvals rescinded.

The FDA, AMA, Union of Concerned Scientists and many other consumer, scientific and agricultural associations support passage of this bill. The agricultural industry and AVMA do not. The Pew Charitable Trust to the Johns Hopkins Bloomberg School of Public Health was commissioned to investigate problems with industrial farm animal production, resulting in the Final Report of the Pew Commission on Industrial Farm Animal Production: I was saddened to read this quote:

“There have been some serious obstacles to the Commission completing its review…while some agriculture representatives were recommending potential authors for technical reports to the Commission staff, other industrial agriculture representatives were discouraging those same authors from assisting us by threatening to withhold research funding for their college or university. We found significant influence by the industry at every turn: in academic research, agriculture policy development, government regulation and enforcement”.

I’ve become uncomfortable with the AVMA’s close relationship with ‘big agriculture’ and their stance on this bill, primarily because the AVMA is supposed to represent me and my colleagues. I’ve read the entire Pew Commission report (http://www.ncifap.org/_images/PCIFAPFin.pdf) as well as the AVMA’s response to it (http://www.avma.org/advocacy/PEWresponse/PEW_report_response.pdf), and I remain unconvinced that AVMA is really advocating for its 67,000+ members (constituting about 86% of veterinarians in the U.S.).

What I’ve gleaned from the response is this:
1. AVMA disagrees with the Pew’s contention that prophylactic use of antibiotics in food animal production can be classified as “nontherapeutic”. AVMA says that antibiotics recommended for feed efficiency or growth promotion prevent or treat subclinical disease. My take: antibiotics NEVER *prevent* disease – they don’t work when bacteria are not present. So they are preventing undiagnosed, uncharacterized bacterial diseases before they become clinical. I was taught in vet school that antibiotics should be used intelligently, with knowledge of what kind of bug is likely present in a documented infection. Maybe that’s good, maybe it’s not, but the point being raised is that widespread indiscriminate use is EXACTLY what causes antibiotic resistance.

2. AVMA believes that everyone is all up in arms about nothing until risk assessments have been done. In fact, there are 4 strong studies mentioned in the Pew report that suggest CAFOs contribute to environmental pollution, and the AVMA refutation quotes from one of them (p. 26) that the present study is only preliminary and deserves further study. Um, this is a common dissimulation pretty much required of any author publishing a strong but small or early study in an area. That doesn’t lessen the strength of the association in this case.

3. Weirdly, the Pew report says that after the antibiotic ban in Sweden and Denmark, animal reservoirs for antibiotic resistant pathogens were reduced and that there was no diminishment in animal health (citing a 2002 WHO report -Impacts of antimicrobial growth promoter termination in Denmark. In: International Invitational Symposium: Beyond Antimicrobial Growth Promotersm in Food Animal Production. Panel wir (ed). Who Department of Communicable Diseases, Prevention and Eradication: Foulum, Denmark.). AVMA directly disputes this, and yet neither report give references to peer-reviewed publications. AVMA cites a report from Denmark in 2007 (http://www.danmap.org/pdfFiles/Danmap_2007.pdf) That summary report says things like this:

“The veterinary antimicrobial consumption in animals increased by 5.2% from 115.2 tonnes in 2006 to 121.1 tonnes in 2007.”

“These results support that the use of antimicrobial agents might select for multiple resistant clones and that this might be the driver of changes in antimicrobial resistance within a serovar.”

“Increased use of cephalosporins in the animal production and for humans has undoubtedly led to the present situation with increasing prevalence of ESBL producing bacteria.”

” Like in previous years, resistance to ciprofloxacin, nalidixic acid and tetracycline was significantly higher in C. jejuni from imported broiler meat compared to Danish broiler meat.”

I did not see the following referenced inn the AVMA report, which actually DOES support its position: http://jac.oxfordjournals.org/cgi/reprint/52/2/159.pdf

My take: it’s too early to tell if animal health has really declined from the antibiotic ban by what is now almost the entire EU (if Pew is correct), but by 2007, we are still documenting the danger of using antibiotics prophylactically in food animals.

4. AVMA notes that one cannot make assumptions about the level of animal health based on the size of the farm, and imputes that Pew seems to have a bias against big farms. AVMA pointedly avoids referring to intensive and factory farms, which is what MOST if not all of these large farms do. They even defend big farms by saying that more veterinarians are employed by big farms than small ones, saying that veterinary oversight is a critical preventive strategy. I agree, but I’m not sure that’s why big farms employ more veterinarians – maybe it’s because big farms express more production-based illness. While I would like to support large animal veterinarians, I do think we need to take a looking glass to this defense by AVMA.

5. Pew makes quite a few recommendations for increased monitoring and regulation by government agencies. AVMA counters most of the recommendations with the claim that the infrastructure is already there. Yeah, but…is it working?

6. Pew claims that CAFOs have serious detrimental effects on the environment, particularly because of animal waste. They show how large and small farms use recycled manure effectively as fertilizer. Strangely, AVMA attacks Pew’s contention that CAFOs have detrimental effects, then go on to show how large farms use recycled manure as fertilizer. Whatever, but I wonder, don’t we get E.coli and salmonella infected produce because…the big CAFOs are leaching or selling manure contaminated with antibiotic resistant bacteria? Hm?

7. AVMA makes a very reasoned response to the Pew’s contention that animal welfare is suboptimal in CAFOs, but it doesn’t directly address some of the examples given by Pew. I’ll go back to my old favorite- ramming a metal tube down a duck’s throat for weeks in order to make fois gras isn’t *proven* to be painful (maybe because no one has bothered to study it), but let’s have a little common sense, shall we? We know that if we wear a parachute when falling out of an airplane, we are likely to have fewer injuries and that if we stop catastrophic bleeding, we’ll probably feel better and have a chance of living longer. Do we really need studies to tell us that this is unpleasant for the duck? Or that dehorning and castrating cattle without anesthesia is painful? Or that amputating tails on dairy cattle and sheep without anesthesia is painful?

AVMA may be correct that we can’t guess at the unintended consequences of banning prophylactic antimicrobial use in food animals – I’ve no doubt about that. But I’m a little confused by a minor hypocrisy I’ve seen lately. Recently I brought up the possibility of rabies vaccine exemptions for sick pets, and was thumped down at my local VMA because the people accustomed to working with public health and political officials said ‘if we were blamed for even ONE human death from rabies, the consequences would be unimaginable’. I ask now – have we been responsible for even ONE human death by giving intensively raised, stressed out food animals antibiotics that contributed to bacterial resistance? I fear that our use of antibiotics to support an intensive production system is unfair to animals, and in addition enables Americans to eat more animal protein that makes them fatter and unhealthier with each passing year.

I appreciate AVMA’s need to rely on science-based policy making, but where science is absent, we cannot fail to act. And anyway, science does not exist in a vacuum, and is accountable, at least where the public health and public funding is concerned, to the public.

However you feel about this, you should read the bill and both reports, then contact your legislator. And if you're a veterinarian, contact your AVMA delegate.

2 comments:

  1. Dr. Wynn,

    I wish I had read your blog post before publishing a similar response. It's very well done. I would loved to have quoted or linked to your post.

    You and your readers my find my recent post on the www.livablefutureblog.com interesting.

    Best,

    Ralph - former Communications Director for the Pew Commission on Industrial Farm Animal Production

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  2. I wish I had as coherent and well prepared rebuttal to AVMA's document as this one. Everyone, please read it. And write to your representatives. And veterinarians - WRITE TO YOUR AVMA DELEGATE to tell them we're not buying into this relationship with big pharma and industrial ag.

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