he World Health Organization is urging countries to restrict the amount of antibiotics given in food animal production by prohibiting their routine use in growth promotion and disease prevention.
The recommendation is one of a number the WHO issued Tuesday aimed at preserving the effectiveness of antibiotics. The vast majority of antibiotics used globally are given to animals used for food production, a practice that is driving the alarming rise of antibiotic resistance among bacteria.
The agricultural sector has resisted limits on the use of the drugs, which are fed to animals to promote growth and to fend off costly infections that might otherwise sweep through factory farming-type operations.
“WHO is fully aware of the impacts of these guidelines that may happen beyond the public health sector,” said Dr. Kazuaki Miyagishima, director of the department of food safety and zoonoses.
“These impacts may be positive or negative. WHO considers, however, that the need to preserve antimicrobials or antibiotics for human medicine by far outweighs possible impacts in some other sectors.”
The recommendations are only guidelines. The WHO does not have the authority to require countries to follow its advice.
But Ramanan Laxminarayan, director of the Center for Disease Dynamics, Economics and Policy, said the recommendations will help health ministries around the world make the case for banning growth promotion to agricultural ministries, which generally wield more power.
“I think the Ag ministry, left to itself, would certainly do nothing. Even pushed by the health ministry may do nothing. But pushed by the health ministry with a WHO recommendation — if nothing else, it stiffens the spine of health ministries in asking for this,” Laxminarayan told STAT.
The WHO said that in some countries, 80 percent of medically important antibiotics consumed are used in the food animal production sector.
Antibiotics have been used in food animal production for decades, since scientists discovered that chickens fed the drugs grew bigger and faster. Animals raised in conditions that could have given rise to outbreaks of costly diseases — crowded quarters, no access to the outside — were also routinely given the drugs to prevent disease.
Some countries have already banned the use of antibiotics as growth promoters in agriculture. The European Union barred the practice in 2006 and a voluntary U.S. ban on use of “medically important” antibiotics kicked in at the beginning of this year.
It’s not yet clear whether the U.S. ban is having any impact. It came with an important loophole — veterinarians can prescribe antibiotics for whole herds or flocks for disease prevention — that experts insist undermines its usefulness.
“No evidence yet and the jury’s still out,” Laxminarayan said. “It’s possible that it’s done something but my bet is it hasn’t done very much, because there are too many loopholes.”
The practice of prescribing antibiotics for a whole flock or herd for disease prevention is one the WHO recommends be banned. The agency is now recommending antibiotics only be given to sick animals, or animals that are part of a herd in which an illness that can be cured by antibiotics has been diagnosed.
“That’s why the WHO guidelines are meaningful, they make clear that in order to stop the misuse of antibiotics in the meat industry we need policies that prohibit antibiotic use for both growth promotion and disease prevention where no illness is present,” said Matthew Wellington, antibiotics program director at U.S. PIRG.
The WHO is also suggesting that when antibiotics are used on animals the drugs should be selected from a list of those that are least important for human health and that a corresponding list of drugs that are critically important for humans should be off limits.