CEI submitted comments this week on an FDA proposed guidance that “encourages” farmers and antibiotics manufacturers to stop using “medically important” antibiotics for livestock growth promotion purposes. When I first started researching the topic, I was sympathetic to the view that at least some of the antibiotics that serve as essential human therapies probably shouldn’t be used in livestock. Sure, I thought, cheaper meat is a huge consumer benefit, but why surrender our last line of defense in the war against germs? I wasn’t as strident as this Los Angeles Times editorial (“Antibiotics and meat don’t mix”), but I did think that maybe a few limits couldn’t hurt.
Naturally, I was surprised to find out how much it really could hurt. There’s actually a pretty large body of scientific research showing how much so-called sub-therapeutic doses actually contribute to consumer health by reducing pathogen loads in animal-derived foods and have a positive impact on human safety (see here, here, here, and here, for just a few examples). Plus, when the European Union banned antibiotics for livestock growth promotion, the expected decrease in the incidence of resistant human pathogens did not occur. In most cases, the number of resistant bacteria continued rising, and in some cases they rose dramatically. Moreover, the incidence of foodborne illness also rose substantially. This shouldn’t have come as much of a surprise, since it’s estimated that livestock uses account for as little as 10 percent of the problem with antibiotic resistant bacteria.
The effect of antibiotic resistance on human health is a complex problem that cannot be solved by superficially appealing solutions. What we need to do is optimize the mix of long-term efficacy and near-term benefits from antibiotics use. We ordinarily expect that market forces can do this kind of thing, and that government regulation would exacerbate problems. The appropriate market forces are attenuated here, however, since the off-patent status of most antibiotics makes them a “commons”, with little incentive for anyone to maximize the net present value. Add in cross-resistance issues (i.e. resistance to one antibiotic can, at times, make a pathogen resistant to another one in the same or similar chemical class), and the end result is that we have to become more creative about instituting the right incentive mechanisms. But one thing is certain: an FDA decision to cut off a whole category of uses because the agency is solely concerned with long-term efficacy is shortsighted at best.
Here at CEI, we have long observed that far too many governmental (and some private) efforts to limit exposure to certain risks unintentionally increases exposure to other, potentially more hazardous risks. Whether you’re talking about human or animal use, banning beneficial uses today can have negative impacts on human and animal health just as surely as a lack of long-term drug efficacy can. And it seems pretty clear that use of antibiotics for livestock growth promotion purposes can coexist with the optimal antibiotics use.