The results are out for this year’s ranking on the top 25 fast foods that are committed to serving antibiotic-free meat to consumers.

Chain Reaction II, a report put together by six nonprofit organizations, evaluated the performance of different fast food restaurants in bringing down or eradicating antibiotic-treated meat in their menu. It shows an improvement from last year’s results, as the number of fast foods that “passed” has doubled.

Panera Bread and Chipotle Mexican Grill still got the highest ranking, with both getting an “A” grade.

Chick-fil-A, one of the pioneers in transitioning to antibiotic-free meat, received the same B rating as of last year. More than 23 percent of the chicken meat it uses is now antibiotic-free.

On the other hand, Olive Garden and KFC were seen to lag behind in terms of effort in dropping antibiotic treated meat.

Overall, however, there was progress, and this was mostly due to the influence of consumers.

“I think it shows consumers are driving change in how meat is produced,” lead study author Sasha Stashwick from the Natural Resources Defense Council, said.

Many food chains are veering away from the use of antibiotics for chicken.

McDonald’s announced early this year to eradicate antibiotics from its chicken supply. McDonald’s said it has completely transitioned to antibiotic-free chicken for almost 14,000 branches in the U.S.

The popular fast food chain received a rating of C plus this year, which is a half grade higher than last year’s. However, McDonald’s has yet to lay down its plans for beef and pork.

Subway climbed to a B grade from last year’s F. The jump could be attributed primarily to the restaurant’s decision this year to completely remove antibiotics from its meat supplies, which is a welcome move considering Subway did not participate in last year’s survey.

Taco Bell and Wendy’s both received a C grade, while Pizza Hut and Papa John’s got a D grade.

Still, 16 of the top 25 fast food restaurants were given an F grade for taking “no action to reduce use of antibiotics in their supply chains," including Burger King, Domino’s, Applebee’s, IHOP, Chili’s and Starbucks.

Antibiotic resistance is one of the most serious health problems that plague doctors and scientists today. Years of eating meat from animals treated with antibiotics has rendered many individuals immune to the drugs. This makes it difficult to treat infections that could have otherwise been addressed by taking antibiotics.

According to a fact sheet released by the World Health Organization: “Antimicrobial resistance (AMR) threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi. AMR is an increasingly serious threat to global public health that requires action across all government sectors and society. Without effective antibiotics, the success of major surgery and cancer chemotherapy would be compromised.”

Every year, 480,000 people develop immunity to drugs that combat tuberculosis. Diseases like HIV and malaria are also becoming more difficult to treat. On top of these, the cost of health care for patients who display antimicrobial resistance is higher compared to those who have not developed resistance.

“Curbing the misuse of antibiotics in the meat industry is a public health imperative,” the study authors wrote.