A Tyson processing plant. (NELL REDMOND/Bloomberg News)

EVERY ONCE in a while, glaciers crack on long-stalled public policy issues. That is the welcome case now after decades of inaction on antibiotic resistance — the emergence of bacteria that can defeat the lifesaving drugs used in human medicine since the 1940s. The problem leads to 23,000 deaths and 2 million illnesses a year in the United States from infections that are difficult or impossible to treat. Now, at last, the longstanding refusal of food producers to recognize and address the problem appears to be waning.

The latest development came Tuesday when Tyson Foods, the largest chicken producer in the United States, said it will attempt by 2017 to eliminate the use of human antibiotics in its U.S. broiler flocks, which are chickens raised for meat. Tyson, which processes 2 billion chickens a year, already had stopped using antibiotics in its 35 hatcheries. For decades, the agriculture industry has defended the use of antibiotics in feed and water to help animals grow faster and larger on the same amount of feed and to prevent disease in a whole flock or herd. Tyson said it would continue to use antibiotics to treat sick animals, which is legitimate, but would strive to eliminate other uses of all antibiotics needed for human medicine.

Tyson’s president and chief executive, Donnie Smith, said the decision was taken out of concern for global threats to human health posed by the rise in resistance. This is an important declaration. In the past, agricultural industry leaders often blamed the problem on overuse of antibiotics by doctors and in hospitals, while claiming agriculture was not the problem. Tyson said it would begin working on ways to cut back on antibiotics in its beef, pork and turkey supply chains.

The announcement follows McDonald’s decision in March to curtail the use of antibiotics in U.S. chicken products over the next two years. Tyson is a major supplier to McDonald’s, so the change makes commercial sense. Taken together, the curbs may prompt others to follow suit. To grow healthy chickens without antibiotics will require changes in procedures and housing, valuable know-how that can be shared.

The Obama administration also has devoted new and welcome attention to the problem, organizing a major study by the President’s Council of Advisors on Science and Technology last year and following up with a proposed budget that nearly doubles the amount of federal spending for combating and preventing antibiotic resistance to more than $1.2 billion. The added resources will go toward improving stewardship of antibiotics — how they are used by doctors and in hospitals — as well as boosting research on the nature of resistance and finding new diagnostics and surveillance methods.

Government action is important, but it is extremely heartening to see Tyson and other companies stepping forward on their own. In the 1980s and 1990s, serious warnings about resistance went unheeded. At long last, this glacier appears to be cracking.