McDonald’s may give us false hope when it comes to the Gaelic sorcery that lurks in its Shamrock Shakes, but the fast food chain just made good on a more important promise. Last year, the home of the Hamburglar announced a plan to stop buying chicken served in its U.S. restaurants from farmers that use antibiotics prescribed to humans. Groups that campaign against the overuse of antibiotics, like the Natural Resources Defense Council (NRDC) and Pew Charitable Trusts are applauding McDonald’s for reaching the milestone ahead of its own deadline.

A move like this — especially made by an oft-maligned fast food giant — really matters. The more we use antibiotics, the more germs evolve to resist them. Human use of antibiotics is the biggest cause of antimicrobial-resistant diseases, but there’s good evidence that agricultural use of antibiotics can contribute to the problem as well.

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The spring of 2015 was a tipping point for corporate pledges: Around that time, just about every U.S. food company that uses poultry (with one defiant exception) made a commitment to stop using antibiotics that are important for human medicine. If you wondered if a corporation like McDonald’s can stick to a pledge, now you know: Reform is possible.

Of course, this doesn’t fix the problem entirely — these pledges apply to the United States, but antibiotic resistance knows no borders. And because we continue to spur the evolution of resistance every time we prescribe antibiotics to humans, we must invent alternatives. To paraphrase words of the great philosopher and space pirate, Mark Watney: In the face of overwhelming odds, we are left with only one option. We’re going to have to science the shit out of this.

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