While recent moves by McDonald’s and Chick-fil-A to reduce the use of antibiotics in the meat they serve may indicate a shift in the industry’s attitude about drugged-up cows and chickens, the overwhelming majority of large fast food and family restaurant chains continue to source beef and poultry raised on unnecessary antibiotics that could result in the spread of drug-resistant bacteria.

A new report [PDF] from a coalition that includes the Natural Resources Defense Council and our colleagues at Consumers Union looked at the nation’s top 25 restaurant chains and graded them on their stated antibiotics policies — which many of them simply don’t have — and on their transparency with regard to these practices.

Only five of the chains earned passing overall grades, with Chipotle and Panera Bread each taking home grades of “A” for having policies that apply to most of their meat products. These companies also have their antibiotics policies available for review online and use third-party audits to verify their antibiotic-free claims.

Chick-fil-A, which is in the middle of phasing out the use of antibiotics in its chicken, scored a “B” but mostly because only 20% of its meat supply meets the drug-free standard at this point. Presumably that grade will improve as it sources more chicken raised without antibiotics. The company’s stated goal is to have 100% drug-free chickens by 2019.

McDonald’s and Dunkin’ Donuts each earned passing “C” marks for having solid policies but currently very limited availability of antibiotic-free meats. McDonald’s has just begun dipping its toes into the antibiotic-free waters, so only a small amount of its menu and meat supply has been affected thus far. According to the report, Dunkin’s policy provides no timeline for its suppliers to meet the standards the company sets for drug-free meat.

After those five companies, it’s a nosedive into “F” territory. A full 14 restaurant chains — including KFC, Olive Garden, Taco Bell, Sonic, and Papa John’s — have no apparent policy with regard to antibiotic use in the beef, poultry, and pork they source. Nor did they respond to the researchers’ survey.

Some chains earned slightly higher “F” grades. For instance, Wendy’s earned some points on the report card for at least making its policy available online. However, while that policy says the chain won’t source meats raised on antibiotics for growth-promotion purposes, it still allows for the widespread use of sub-therapeutic doses of the drugs for the purposes of disease prevention. The problem is that many scientists believe it’s precisely this low-dose, continual prophylactic application of antibiotics that contributes to the development of drug-resistant bacteria.

Subway’s “F” grade was the highest of all the failing chains. The company, which has been the target of a campaign calling for it to switch to drug-free meats, earned some credit because Subway has publicly stated on its website that the company supports the “elimination of sub-therapeutic use of antibiotics.” There have been reports that Subway does soon intend to start buying meat raised without antibiotics, but since the company hasn’t announced any actions to source only drug-free meat, its statement in opposition to the overuse of these drugs may be nothing more than lip service.

“Overusing antibiotics in meat production helps to create drug-resistant superbugs.” said David Wallinga, MD, Senior Health Officer with the NRDC. “Restaurants billing themselves as a ‘healthier’ option, like Subway, have a particular responsibility to live up to that image by reducing antibiotics. Increasing consumer demand for antibiotic-free meat is transforming the marketplace, and the companies continuing with business-as-usual will be left behind.”

“U.S. restaurant chains must take responsibility for how the meat they sell is contributing to the rise of antibiotic resistance.” said Jean Halloran, director of food policy initiatives at Consumers Union, the policy arm of Consumer Reports. “We are urging other major chains, such as Subway and Burger King, to take immediate action in their meat supply chain to address the urgent problem of antibiotic resistance.”

Congresswoman Louise Slaughter of New York — a trained microbiologist and a vocal critic of the use of antibiotics in farm animals — applauded today’s report and called on the failing companies to consider the growing public concern about antibiotic overuse.

“More and more Americans are realizing that the misuse of antibiotics in corporate agriculture is having a direct impact on their own health,” said Rep. Slaughter in a statement. “Antibiotic-resistant infections are on the rise, and the usefulness of one of our most precious medical resources is on the decline… The companies that have failed to change their practices should examine this report and immediately make the change that the American public is demanding. Lives literally depend on it.”

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