Last year McDonald’s made headlines when it announced it would no longer sell chicken raised on antibiotics important in human medicine in the U.S. Today, the chain said it would prohibit the use of antibiotics most valuable in human medicine in chicken served at its restaurants worldwide by 2027.

Antibiotics have long been used on factory farms to prevent disease outbreaks that can occur when livestock live in close quarters. They also tend to speed the growth of animals, which can shorten the time to market for farmers. But the overuse of antibiotics in livestock is one of the major contributors to the development of superbugs—bacteria that are immune to the effects of even multiple antibiotics. Nearly 23,000 Americans die each year from antibiotic-resistant infections.

McDonald’s will eliminate the use of a group of antibiotics the World Health Organization has defined as “High Priority Critically Important” in human medicine in the production of chicken sold at its restaurants worldwide. As of January 2018, the policy would take effect in Japan, Brazil, Canada, and South Korea. McDonald’s chicken produced in Europe, Russia, and Australia would achieve this goal by the end of 2019. However all markets would not eliminate these high-value antibiotics until 2027.

"Overall, as one of the world’s largest food companies, we use our scale as an opportunity to achieve impactful change on a key societal issue," a representative for McDonald's told CR in an emailed statement.

“This move, if fully implemented, will go a long way toward keeping antibiotics working when people need them to,” says Jean Halloran, director of Food Policy Initiatives at Consumers Union, the policy and mobilization arm of Consumer Reports. “While several big chains, such as KFC and Subway, have stepped up their antibiotics policies in chicken in recent years in the U.S., McDonald’s is the first to make such changes in the global supply chain.” (See how the top 25 chain restaurants rate on reducing their antibiotic use in the 2016 Chain Reaction report. This report is produced annually by Consumers Union and several other consumer, environmental, and health organizations. The new report will be out on September 27.)

More on Antibiotics

Currently chicken sold in McDonald’s U.S. restaurants is not raised with any medically important antibiotics, although ionophores (antibiotics only used in animals) are permitted. If any chicken gets sick, it is treated as necessary, but that chicken must be removed from the company’s U.S. supply chain. Under the new policy, however, chickens treated because of a disease outbreak can still end up in chicken products sold at  McDonald’s outside the U.S.

In a meeting with Consumers Union and other consumer and environmental organizations on August 17, McDonald’s said it plans to eventually limit the use of antibiotics in its beef, but it did not specify when that policy will go into effect or what the details might be.

Still, Halloran calls this announcement a “potential game changer” because of the fast-food company’s massive market clout. McDonald’s sells millions of pounds of chicken each year across Asia, Europe, Latin America, the Middle East, and North America, from conventional items that Americans may be familiar with, such as Chicken McNuggets, to some regional adaptations, such as the Seoul Spicy Chicken Burger in South Korea.

“We hope that the action McDonald’s took today inspires other fast food companies to act as well to protect public health,” says Halloran. 

Editor's Note: This article has been updated to include a comment from McDonald's.