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Know the West

Is that MRSA in your porkchop?


I've not written much about antibiotic use (or overuse) in livestock facilities. It always seemed like one of those perennial important-yet-not-going-anywhere topics where a group of concerned scientists write research-based, impassioned letters to the federal Food and Drug Administration listing all the potential consequences, but the agency never takes action.

Which is not to say the exceedingly high use of antibiotics in livestock facilities (as much as 70 percent of the total antibiotics in the United States goes to livestock) is not problematic. It is.

Evidence that antibiotic-resistant bacteria gets from live animals into the meat most Americans eat keeps piling up: In January, scientists sampled 395 cuts of pork from 36 stores in three states. Twenty-six of these harbored methicillin-resistant Staphylococcus aureus bacteria; similar percentages of MRSA, as it is called, have been found in other studies sampling grocery store meat products. Just last week, researchers looking at antibiotic resistance in soil bacteria found that agricultural soils amended with manure from animals treated with antibiotics contained bacteria with a much higher level of antibiotic resistance than the bacteria found in non-amended soils.

As far back as 1977, the FDA was concerned about the impacts of antibiotic-resistant bacteria from feedlot animals, but despite being required by law to take action on this concern, it never did. And while study after study has piled up over the years, each showing an increase in antibiotic resistant bacteria, in many cases spreading from animals to humans, the FDA has sat on its hands. In fact, just this December, it stopped its process (began in 1977 but never completed) to withdraw the antibiotics penicillin and tetracyclines from what's called "non-therapeutic" livestock use, which basically means the antibiotics are fed to livestock whether they are sick or not, as a preventative measure and to promote their growth.

But just last week, a federal judge ruled the FDA has to hold hearings on the safety of antibiotic use in livestock and then make a decision on withdrawing them. In its December decision, FDA had said instead it planned to focus on industry-supported "voluntary" measures, to curb antibiotic overuse. The judge said that wasn't enough.

"The ruling compels FDA to take action on its own safety findings by withdrawing approval for most non-therapeutic uses of penicillin and tetracyclines in animal feed, unless the industry can prove in public hearings that those drug uses are safe," the Natural Resources Defense Council, which was part of a coalition that sued the FDA, wrote in a press release.

Now that this ruling has been handed down, it looks like FDA will be required to hold hearings where the pharmaceutical industry will be forced to defend the use of this "growth promoter" antibiotic use and prove it is not dangerous to humans. The hearing schedule has not been pinned down yet, and will be worked out between the coalition that sued FDA and the agency.

When the hearings take place, it seems as if the antibiotics manufacturers will be hard pressed to defend the position that non-therapeutic use does not pose risks to humans. As the excellent Wired "Superbug" blogger Maryn McKenna, who has covered the issue of antibiotic resistant bacteria extensively, writes:

"A good portion of the scientific evidence, though not all, supports the contention that growth promoter antibiotic use encourages the evolution of antibiotic-resistant bacteria that move off the farm to create antibiotic-resistant illness elsewhere."

It's not rocket science that when animals in close quarters are administered exceedingly high levels of antibiotics, the bacteria living in those systems quickly evolve to be resistant to such bacteria. Nor is it a giant scientific leap to hypothesize, and then prove, that those resistant bacteria get into the animals' meat and their manure, and then sometimes into humans, where treatment options become increasingly limited due to the drug resistance of those bacteria.

It's a little encouraging to know that, after 35 years of inaction by the agency in charge of protecting consumers from these dangers, the body of scientific research on antibiotic-resistant bacteria spreading from feedlots to humans will be aired in front of the public. While curbing the use of antibiotics won't fix all the problems inherent in the factory farm system, it will at least shine a light on that system, and perhaps improve one harmful aspect of it. Here's hoping.

Stephanie Paige Ogburn is the online editor at High Country News.

Image of pork chops courtesy Flickr user Artizone.

Image of a flesh eating, antibiotic resistant methicillin-resistant Staphylococcus aureus staph infection (and there are many worse photos out there) courtesy Flickr user Herbie Robinson.