The international community needs to set hard targets for using antibiotics in agriculture and should act as soon as possible to reduce the drugs’ use, a project chartered by the British government said in London today.
The Review on Antimicrobial Resistance, which has been examining how to fix antibiotic overuse and resistance for more than a year—since it released the jaw-dropping estimate that resistant bacteria will kill 10 million people per year by 2050—said in a report and press conference that there can no longer be any dispute that farm misuse of antibiotics contributes to the global burden of resistance.
But to remedy that, the group makes a novel proposal. Instead of focusing on categories of antibiotic use—the path followed by Europe and the United States, which have placed controls on the daily micro-doses called growth promoters—it recommends focusing on quantities. It proposes that the international community agree to a maximum allowable amount of agricultural antibiotic use, while permitting nations to decide how best to meet it—provided that they do meet it within 10 years.
It also proposes what such a standard might look like: less than 50 milligrams of antibiotic per kilogram of livestock under production—about what is now used in Denmark, a country that operates intensive agriculture with minimal antibiotic use, and more than three times what is used in the United States.
At the same time, the Review calls for close attention to which antibiotics are allowed in agriculture, and recommends that nations carve out an international agreement on which crucial last-resort drugs ought to be reserved for human medical use. The danger of using antibiotics in agriculture without regard to their scarcity was underlined in the past few weeks when researchers revealed that resistance to colistin, a last-gasp antibiotic preserved from the 1950s, is moving through pigs, retail pork and chicken meat, and human patients in China, and appearing in Europe.
The target-based approach proposed today resembles the national emission limits that are under discussion in Paris this week at the international climate talks. Lord Jim O’Neill, the Review’s chairman and the former chief economist for Goldman Sachs, said in an interview that the timing of the new report was accidental, but that the group kept in mind the disputes between rich and developing nations that have hobbled agreements to slow global warming.
“What we’re really saying is, just to have a ban on use for growth promotion is a bit blunt,” he said by phone. “If you have an overall limit globally and for each country, it in essence allows them to shift their approach, depending on what their own perception of the relative domestic challenge is.”
Avoiding bans by category, he said, would encourage farm-antibiotic control even in nations that have not developed their agricultural sector enough to use the drugs much. At the same time, it would prevent developed-world countries with large amounts of intensive, antibiotic-using agriculture from executing a dodge that advocates have warned about: redefining banned growth promoters into another category of drug use, such as disease prevention, so that growth-promoter use appears to diminish but real change does not occur.
The proposal released today marks the first time that any group has mapped out a specific target for reducing antibiotic use in meat animals, though plenty of institutions—from the World Health Organization to the White House to medical and public health organizations—have recommended recently that reductions be made.
Countries vary greatly in the quantities of antibiotics they use in farm animals.
Grophic courtesy the Review on Antimicrobial Resistance.
Routinely giving antibiotics to meat animals that are not sick has been standard practice since the 1950s; and since at least the 1970s, researchers have shown that using antibiotics in that manner allows antibiotic resistance to emerge and travel off farms. In its report, the Review endorses this conclusion, saying that it conducted a review of the scientific literature that found more than 100 papers confirming the link, and only seven that argued there was no link.
“We believe that there is sufficient evidence showing that the world needs to start curtailing the quantities of antimicrobials used in agriculture now,” the report says. “Given all that we know already, it does not make sense to delay action further.”
Advocates and researchers who have been pressing for reductions in agricultural antibiotic use said Monday that this approach has the potential to create real change.
“I commend the Review on Antimicrobial Resistance report, and its call for the creation of a global reduction target of antibiotic use in food animal production,” Laura Rogers, the deputy director of the Antibiotic Resistance Action Center at George Washington University, told me by email. “In order to bring down antibiotic resistance, we must set reduction goals in food animal production.
“Here in the U.S., President Obama has launched a national action plan to combat antibiotic resistance and included practical measures for improved stewardship of antibiotic usage in human medicine, along with time-bound, measurable goals for reductions. Yet it was virtually silent on animal use and offered no measurable goals for antibiotic reductions in food-animal production, nor did it address antibiotic use for routine disease prevention. We must set a meaningful reduction goal of antibiotic use in agriculture here in the U.S. and we need to put a system into place to ensure we meet the goals we set.”
Most of the antibiotics used on livestock go to animals that are not sick, and are not used to treat disease. Graphic courtesy the Review on Antimicrobial Resistance.
Karin Hoelzer, PhD, a veterinarian and officer at the Pew Charitable Trusts, told me by phone: “This is an international problem that requires international action, even though it is up to every country to make a difference and to take action on a national level.” She cautioned that attempting international negotiations on this touchy issue would require important first steps, chiefly reaching agreement on just which human-use antibiotics deserve the most protection from misuse. The Review report says that at the moment there are at least two different schemes defining which drugs are most precious, and recommends those be harmonized within a year. “That is a really important first step,” Hoelzer said.
Paralleling its evaluation of agricultural antibiotic use, the Review also tackles the tough subject of antibiotic pollution, calling for strict controls on antibiotic makers to prevent their dumping manufacturing waste—effectively, raw antibiotics—into water sources. And it calls for much better data-gathering on farm antibiotic use and antibiotic-manufacturing emissions, saying that good information is crucial to tracking the emergence of resistance and the paths it takes to human patients.
Most of the antibiotics used in agriculture are also used in human medicine.
Graphic courtesy the Review on Antimicrobial Resistance.
The recommendations published today are another chapter in a two-year examination of antibiotic resistance that the Review is undertaking at the request of British Prime Minister David Cameron, who chartered the group in July 2014. It has also examined the worldwide burden and cost of resistance, the need for more spending by governments, the difficulty of reviving antibiotics manufacturing and the challenge of developing rapid diagnostic tests and devices that could improve prescribing and lessen misuse.
The group’s findings will be summarized in a final report that it is expected to present to Cameron in mid-2016. O’Neill said their goal will be to develop strategies for dialing back resistance that can be backed by the United Nations and World Health Organization, and crucially, by the Group of 20, the international forum of major economies, which committed at the end of its recent meeting in Turkey to examining antibiotic resistance as a global threat. The leadership of the G-20 has just been taken by China, now the world’s leading producer and consumer of antibiotics. With the news of the emergence of colistin resistance, China may feel it must be seen to be taking action to combat drug resistance worldwide.
“One of the most wonderful things about leading this effort, as we creep through it, is that I can feel there is more and more response to the noise we are making,” O’Neill told me. “”I do feel this is being taken seriously internationally.”