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Chickens in intensive confinement. Photograph via Google Images (CC).

Farm Antibiotics: Still Headed In The Wrong Direction

New federal data released at the end of last week indicates that sales of antibiotics for use in food animals in the United States are still rising, despite public pressure to change the practice and condemnation by medicine that farm misuse and overuse is contributing to antibiotic resistance that threatens human health.

That’s not good. It’s especially not good because the numbers just released cover the year 2014—the first year in a voluntary three-year period, set by the Food and Drug Administration, during which use of farm antibiotics is supposed to be reduced. If agriculture and the veterinary pharma industry didn’t manage reductions in Year 1, they have a hard task ahead of them to create significant change in Years 2 and 3.

Here’s the short version of the news about the numbers:

  • The amount of all antibiotics sold for use in food animals in the United States (in 2014: 15.36 million kilograms, or 33.86 million pounds, or 16,930 tons) rose 4 percent between 2013 and 2014, and 22 percent from when the FDA began measuring in 2009.
  • The amount of “medically important” antibiotics—that is, ones that are also used in human medicine, which makes producing resistance against them doubly dangerous—rose 3 percent from 2013 to 2104, and 23 percent from when the FDA began measuring in 2009.

There are a lot of other details in the report—formally, the 2014 Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals, and informally “the ADUFA report” for the legislation that created it—that are troubling and important. I’ll get to those in a minute. If you’ve been reading here for a while and know the basics, skip down to this paragraph. (If you’d like to catch up on your own, my past posts are here and here.) Otherwise, keep reading for a short course on why this is a big deal.

OK so: Whenever we give an antibiotic, we take the risk that resistance—bacteria’s ability to evolve molecular defenses against compounds sent to kill them—will result. Thus, in human medicine, we try to use antibiotics responsibly: giving them in the right dose, in the drug family that will work against the organism, and allowing for any resistance that has already developed. What we’re doing, when we tune antibiotic use in that manner, is balancing the benefit of achieving a cure against the risk that resistance will arise.

In agriculture, over decades, we’ve allowed that risk-benefit balance to tilt all out of whack. Only a small percentage of the antibiotics given to animals that will become food, in the US and worldwide, actually go to cure illness. Much larger amounts go either to prevent the possibility of illness—caused by the conditions animals are kept in, not by known disease in the flock or herd—or to improve the rate at which they put on tasty muscle mass. In other words, most of the use of antibiotics in food animals is all risk of resistance, without achieving the benefit of a cure.

(And resistance does arise, and passes from animals to humans. I’ve written many posts on this, but for a short version, see this recent one on a UK government-chartered report examining the evidence.)

To rectify that risk-benefit imbalance, the FDA created a voluntary program at the end of 2013 in which veterinary-antibiotic manufacturers were invited to change their drugs’ labels so that using antibiotics for one of those two risky uses—”growth promotion,” or encouraging weight gain—would no longer be legal. (The FDA made it voluntary because, for decades, Congress prevented the FDA from regulating farm antibiotic use.) The agency gave the manufacturers three years to change their labels, with the goal of squeezing growth promoters out of the market by the end of 2016. By mid-2014, all the veterinary-antibiotic manufacturers selling in the US said they would go along with the new policy. But based on the numbers just released, no one is moving very fast.

OK, we’re caught up. Here are the details of ADUFA 2014.

The first important point is the trend: more use when sales should be decreasing.

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Sales of all antibiotics used in food animals (lower yellow box), and farm antibiotics that create resistance hazardous to humans (upper yellow box), are rising. Graphic from ADUFA 2014 report, table 10. Original here.

Second concern: How large a percentage is still going to growth promotion. Here the report shows how difficult parsing agricultural antibiotic use can be: Antibiotics being sold for animal use are listed as growth promotion (“production”) or growth promotion and also disease prevention (“production/therapeutic”). Overall, less than one-third of the antibiotics sold for animal use are going only for the treatment of an identified disease; the rest are going for growth promotion, or to guarantee that animals won’t be made sick by the conditions of intensive confinement, or both. (The messiness of these distinctions explains why, earlier this year, California banned any antibiotic use  in livestock that is not treatment of a diagnosed disease.)

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Only 29 percent of antibiotic sales (sum of the yellow boxes) go for disease treatment; 71 percent (sum of the orange boxes) go for disease prevention or growth promotion. Graphic from ADUFA 2014 report, Table 5; original here.

Another concern—or, maybe, question: If federal policy at last is focused on reducing antibiotic use on farms, why are these amounts and percentages still so high? This third chart from the ADUFA report explains it: Almost all of the antibiotics going for farm use in the United States are sold over the counter—that is, no one is involved in the decision to buy or use them but the farmer him- or herself.

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Almost 99 percent (sum of the yellow boxes) of the antibiotics sold for use in food animals in the US are sold over the counter, that is, without a prescription. Graphic from the ADUFA 2014 report, Table 6; original here.

How antibiotics are acquired by farmers is supposed to change in the near future. Along with its policy on voluntarily relinquishing growth promoters, the FDA has also directed that antibiotics used in any other manner—to treat or prevent disease—must be ordered by a veterinarian. That change is meant to shut down over the counter sales, and it should take effect by the end of 2016. But, as these 2014 numbers show, over the counter sales are flourishing to this point.* (And as I’ve written elsewhere, other countries that attempted this distinction soon found that it created huge loopholes.)

To sum up: After decades of political interference, the FDA created a policy that should reduce unwise overuse of antibiotics in livestock raising. It gave manufacturers, and by extension producers, three years to get used to the idea. One year in, nothing in the numbers suggests that veterinary pharma, or agriculture, is moving quickly. This could be recalcitrance, refusing to cooperate; or it could be brinksmanship, waiting until the last moment before the 2016 deadline crashes down.

Until we get through 2016, we won’t know. But right now, the numbers don’t look good.

Here are what researchers and advocates on the issue had to say about the FDA report:

Laura Rogers, deputy director, the Antibiotic Resistance Action Center, George Washington University: “We’ve seen a lot of dire news lately on the crisis of antibiotic resistance, including the discovery of a dangerous new antibiotic-resistance gene that has spread from livestock to people in China and has just been found in Europe. This news underscores why in order to slow the spread of antibiotic resistance, we must reduce use in all settings, especially in animal agriculture, where the majority of drugs are sold for use… We need much greater reductions if we are truly going to protect human health and make headway in slowing the global threat of antibiotic resistance.”

Karin Hoelzer, veterinarian and microbiologist, The Pew Charitable Trusts: “This report shows a 23 percent increase in the amount of medically important antibiotics sold from 2009 through 2014, but it doesn’t tell us how or why these drugs are actually being used on the farm. It reinforces the need for additional data about how antibiotics are being used in animals – and the resources to collect that data.”

Avinash Kar, senior attorney, Natural Resources Defense Council: “We can no longer rely on the meat and pharmaceutical industries to self-police the responsible handling of these precious drugs. FDA must follow the lead of California and outlaw routine use of antibiotics on animals that are not sick in meat production nationwide. If we want to keep our antibiotics working for people when we need them, the agency must take urgent action.”

Susan Vaughn Grooters, policy analyst, Keep Antibiotics Working: “This troubling trend reaffirms that an approach based largely on voluntary industry reductions, is inadequate faced with the public health crisis of antibiotic resistance. There is no indication that FDA’s change in policy has yet resulted in any meaningful reductions on antibiotic sales and usage in food animal production. Over the counter sales clearly indicate that veterinary oversight couldn’t come soon enough.”

*Footnote: People often ask me whether it’s really true that antibiotics can be bought over the counter, without a prescription, for veterinary use. They assume it’s an exaggeration. As proof it is not: Here are 2 lbs of aureomycin (also called chlortetracycline), which I bought online without anyone asking me whether I was a veterinarian, or treated or possessed animals, or, well, anything at all.

Aureomycin (chlortetracycline) bought online.
Aureomycin (chlortetracycline) bought online.
Photograph by Maryn McKenna.