The U.S. Food and Drug Administration is asking veterinary drug companies to voluntarily agree to make it illegal to feed healthy animals some antibiotics. If the antibiotic is on the FDA’s list of drugs that are related to drugs used to fight infections in people—including everything from bronchitis to urinary tract infections to Lyme disease to infections after surgeries—then the agency is asking companies to stop their use for fattening up pigs, chickens and other animals people eat.
The move is meant to reduce the amount of antibiotics farmers feed to food animals. “With these changes, there will be fewer approved uses [for animal antibiotics] and the remaining uses will be under tighter control,” Michael Taylor, the FDA’s deputy commissioner for foods and veterinary medicine, said in a conference call for reporters. Scientists have long warned that the constant use of antibiotics in farm animals is a threat to human health, but U.S. agencies haven’t taken a lot of official action on the issue.
After talks with industry folks, FDA officials believe companies will comply with the new program. Making the changes this way—voluntarily—is faster than the FDA’s legal process, which would require the agency to evaluate every antibiotic individually, Taylor added.
Critics of the program say it may not make much of a dent in how antibiotics are used on animal farms. “Even if it were observed by the industry, there’s no guarantee that the usage profile for these drugs would change,” Keeve Nachman, who studies food production at the Johns Hopkins Bloomberg School of Public Health, tells Popular Science. Nachman and other critics worry farmers and farming companies will simply switch from saying the medicines are for making animals grow, to saying they’re for preventing illness in animals. For many antibiotics, the dosages for both indications are similar.
Why cut down on antibiotic use? Concern about the rise of antibiotic-resistant microbes is the primary reason. Such microbes can give people diseases that no modern antibiotics are able to cure. One recent U.S. Centers for Disease Control and Prevention report found that 2 million Americans get antibiotic-resistant illnesses every year and 23,000 Americans die from them.
These illnesses evolved recently, after decades of unnecessary antibiotic use among farmers, doctors and patients. On many farms, animals eat low doses of antibiotics mixed into their food, either to make them grow faster or grow more on less food. It’s not clear exactly why low-dose antibiotics fatten animals up, although one study done in mice hints that it’s got something to do with changes to the animals’ gut microbes.
Farmers and farming companies don’t need prescriptions from veterinarians to get drugged feeds; they get them from feed stores. Once inside livestock’s bodies, the medicines kill off most microbes, but leave behind so-called superbugs that are able survive a round of antibiotics. The low doses used to promote growth are especially prone to leaving superbugs behind.
Eventually, the resistant microbes come out of the animals’, uhh, other ends, and from there may spread to crops as fertilizer, get carried around by birds and eventually make it to people. Multiply this by millions of farm animals and years of antibiotic use and you eventually breed large populations of superbugs.
Getting farms to stop using antibiotics unnecessarily would be a major step toward slowing the evolution of superbugs. The argument now is whether the FDA’s new program actually does this.
Critics worry that farms will continue to use antibiotics widely while complying with the FDA’s request to the letter. This blog post from National Resources Defense Council lawyer Avinash Kar summarizes that argument. The National Resources Defense Council has sued the FDA over the use of antibiotics in farm animals.
“This is a critical issue because obviously we want the effect to be real and the effect on resistance to be real,” FDA’s Taylor said. The key to addressing the issue, Taylor said, is that when companies agree to the new FDA program, non-growth uses of antibiotics should require the equivalent of a prescription from a veterinarian. “It’s a big shift from the current situation,” in which animal antibiotics are available to farming companies over-the-counter, Taylor said.
Others are not so sure veterinarians will act as good gatekeepers to reduce unnecessary antibiotic use. “It potentially could help, but unless these veterinarians believe these uses are creating a public health problem, they have no incentive to do that,” says Steven Roach, a program director for public health at the Food Animal Concerns Trust, a farm animal welfare organization based in Chicago.
Companies have 90 days to write to the FDA, saying they intend to follow the new program. After that, they’ll have three years to phase in the changes.