Last week, the FDA withdrew two 34 year-old proposals to limit the use of two non-therapeutic antibiotics (penicillin and tetracycline) in cattle feed, opting instead to recommend voluntary withdrawal. This is particularly outrageous in light of the dozens of countries that have instituted these bans successfully.
Upon hearing this latest bit of news, I got in touch with Dr. David Wallinga, a renowned expert in the link between the ubiquity of antibiotics in animal feed and increased human resistance to these drugs. I had the pleasure of meeting Dr. Wallinga at the American Dietetic Association annual conference this past October, where he was part of a point-counterpoint panel on that very issue.
I wanted to get his thoughts on the FDA decision, as well as on the public health threats posed by antibiotics in cattle feed. His responses below:
As someone whose work focuses on issues of antibiotic use in animal feed, how surprised — if at all — were you by the FDA’s decision last Thursday to withdraw their proposals to limit the use of non-therapeutic penicillin and tetracycline, and instead rely on voluntary guidelines to industry?
I was not very surprised. For some time, both privately and publicly, the FDA has admitted that they consider it too hard to act proactively on their congressional mandate to protect public health. Instead, their chosen path time and again has been to ask the regulated industries to voluntarily act, which of course they have every incentive – financial and otherwise – to not do.
The FDA first went on record with concerns about a possible link between antibiotics in animal feed and human antibiotic resistance in 1977. Why has there been such little action since?
The FDA proposal in 1977 was not acted upon because congress shut the FDA down. It’s fair to say that FDA has acted afraid of its own shadow ever since. It certainly doesn’t help that the FDA relies upon the industries that it is supposed to regulate for much of the budget that it relies upon to pay staff and to operate. Could one design a regulatory agency more emasculated or incapable of protecting the public? I think you would be hard pressed.
What do you consider to be the most flawed arguments in favor of administering antibiotics in cattle feed?
Just about all of them, based upon what every microbiologist knows about bacteria and their tendency to get more resistant the more exposed they are to antibiotics. The industry arguments really haven’t a leg to stand on, no matter how much they protest to the contrary.
(Note: One statement Dr. Wallinga made at the point-counterpoint panel that has stuck with me: antibiotics for animal feed were approved decades ago, when their impact on human gut flora wasn’t a requirement for approval. The public health community has since pointed out some troubling implications).
For those who may not be aware, can you provide an overview of the link between antibiotics in animal feed and “superbugs”? Also, given the recent FDA decision, how much worse do you think this situation can get?
Well to answer the latter question first, it can get worse by more people dying of resistant infections even more quickly. We know that is already happening, and the overuse of antibiotics in agriculture has speeded that process. But deaths and expensive illness from resistant infections are likely to get much worse before — or if — they get better.The linkages between use and resistant infections goes something like this:
- Antibiotic use drives resistance.
- 80% of antibiotic use occurs in agriculture; about three-quarters of this use is thought to be via the addition of antibiotics to animal feed for animals that aren’t yet sick.
- Over half the latter is thought to be in the form of antibiotics that are “medically important” meaning they are identical or nearly so to drugs also used in human medicine — meaning, classes of antibiotics like penicillins and tetracyclines.
- Over time, superbugs have gotten more lethal because they are not only getting resistant to more drugs, but also that resistance is physically linked. That means smart superbugs can “teach” other bugs to be resistant to multiple drugs very quickly by transfering the genes or gene-based information that makes them multidrug resistant in one fell swoop. Because of the huge use of antibiotics in farm environments, we are creating reservoirs of these superresistant bugs around farms, among farmworkers and in the food supply. The creation and rapid spread of more lethal and more resistant strains of superbugs is accelerating far, far quicker than the almost non-existent creation of novel new antibiotics. This is a recipe for disaster as doctors are literally running out of antibiotics to try and use in patients infected with harder and harder-to-treat bacteria.
David Wallinga, M.D., M.P.A., is Senior Advisor in Science, Food and Health, at the Institute for Agriculture and Trade Policy. Dr. Wallinga applies a systems lens to think about health impacts of food and how it is produced, processed, packaged and distributed in today’s global, industrialized food system. From 2009 through 2010, Dr. Wallinga was a William T. Grant Foundation Distinguished Fellow in Food Systems and Public Health at University of Minnesota, School of Public Health. He received a medical degree from the University of Minnesota Medical School, a master’s degree from Princeton University and a bachelor’s from Dartmouth College.