Misuse and overuse of antibiotics is fueling a scourge of drug-resistant infections, a dire threat to public health. While doctors are working to become better stewards of the life-saving medicines, many health experts are taking aim at farms, which soak up nearly 80 percent of the antibiotics sold in the United States.

Today, researchers at the University of California, San Francisco are calling commentary in the American Journal of Public Health to call on the country’s hospitals to ditch meat from farms that pump their livestock with antibiotics. The UCSF Medical Center’s cafeterias and catering services have been phasing out such meat for the past two years, they report. And the effort parallels that of some restaurant chains, most notably, Chipotle. The strategy could limit life-threatening infections and help preserve the effectiveness of antibiotics, experts say.

The fear is that meat from antibiotic-friendly farms harbors drug-resistant bacteria, which could spread to humans when they touch or eat the meat.

Those drug-resistant microbes arise from the routine practice of giving animals unnecessary doses of antibiotics. Instead of treating the occasional sick animal, farmers often pepper their flocks and herds with low doses of antibiotics to curb potential illness—and to fatten them up. A small helping of the drugs can quell symptomless infections and help animals grow faster and bigger on the same amount of food. The practice increases the profit margins on livestock but also provides an ideal breeding ground for drug-resistant microbes.

With the risk of those potentially deadly microbes spreading to humans, the practice is far too costly. Drug resistant infections sicken at least two million people each year in the United States, killing at least 23,000, as the Centers for Disease Control and Prevention reports. And treating those antibiotic resistant infections costs the US health care system up to $34 billion a year, according to the Infectious Diseases Society of America.

Today’s call by UCSF doctors follows a landmark move by the state of California last weekend. Gov. Jerry Brown signed into law the country’s toughest restrictions on agricultural antibiotic use. The law, which will come into effect in 2018, bans farmers from overusing medically relevant antibiotics on their livestock.