How does the livestock industry talk about antibiotics? Well, it depends on who’s doing the talking, but they all say some version of the same thing. Take the National Cattlemen’s Beef Association; they say there is “no conclusive scientific evidence indicating the judicious use of antibiotics in cattle herds leads to antimicrobial resistance in humans [MRSA].”

Or Ron Phillips of the Animal Health Institute (a drug-industry front group). In an interview on Grist last year, he said that before you can draw any conclusions:

… You have to look at specific bug/drug combinations and figure out what are the potential pathways for antibiotic-resistant material to transfer from animals to humans. Studies have been done, and have come to the conclusion that there is a vanishingly small level of risk.

The message is clear. Until scientists trace a particular bug from animals to humans and show precisely how it achieved resistance and moved from farm to consumer, there’s no smoking gun. Thus industry leaders’ heads can remain firmly buried in the sand.

Ladies and gentlemen, we now have a smoking gun! NPR reported on it first; here’s their take:

A study in the journal mBio, published by the American Society for Microbiology, shows how an antibiotic-susceptible staph germ passed from humans into pigs, where it became resistant to the antibiotics tetracycline and methicillin. And then the antibiotic-resistant staph learned to jump back into humans.