An recent news article from Thailand entitled Superbugs lurk in local food systems came to my inbox the other day. There’s nothing really new in it, but it has some talking points that are commonly used (and sometimes misused) when we discuss and debate antimicrobial use (AMU) and antimicrobial resistance (AMR) in food animals.

Here I’ll break down these various statements, not really to defend, support or criticize them, but hopefully to show some of the complexities and challenges around these issues (the article quotes are in italics).

Antibiotics are the silent props of the factory farm system, preventing stressed, confined animals from otherwise getting sick due to the dismal conditions they live in.

  • I don’t like it when articles start with “factory farm.” It shifts the focus from AMU/AMR to the ethics of large scale food animal production systems. That’s not to say there aren’t (sometimes major) issues there, but we need to separate those out. Some huge farms do a great job with AMU (and welfare). Some small farms are horrible with both. Certainly, large farms can have more challenges, and bad practices can have disproportionate impacts when they involve so many animals. However, “big = bad” and “small = good” isn’t accurate. There’s likely a sweet spot in the middle, where farms are big enough to have the expertise and finances to improve animal health and animal management, incorporate optimal disease prevention strategies and have a good antimicrobial stewardship program, but small enough to limit some of the other concerns that often come with large-scale production. These factors also vary a lot by animal species.
  • Like most things around AMR in livestock, over-simplification and buzz words can make us lose focus.

Around 131 000 tons of antibiotics each year are used in farming globally, comprising 3/4 of the antibiotics produced in the world, and the amount is expected to rise to 300 000 tons in 2030, according to an academic article entitled “Reducing antimicrobial use in food animals” published in the journal Science in 2017

  • There’s no doubt massive amounts of antibiotics are used in animals, mainly in food animals. The relative use of various drug classes in food animals and humans tends to quite different, and we’re trying to foster less use of “critically important’” antimicrobials in animals.
  • Looking at the mass (tons) of antimicrobials used is (relatively) easy, but oversimplifies things and can therefore be misleading. Explaining this alone could be a whole series of blog posts, so I’ll just add a few comments for now. Not all drugs are equally potent. If I change from using a drug that is dosed at 20 mg/kg two times a day to one that is used at 2 mg/kg once a day, I’ve dropped from 40 mg/kg/d to 2 mg/kg/d.  If I look at tons of drug used, that would look like a huge improvement, and a farm could do that quite easily in some situations. But, if in the process they switch from a lower-tier drug (e.g. a penicillin) to a “highest priority critically important” antibiotic, that would be a huge mistake that can cause a lot of harm, even though it looks good from a tonnage perspective.
  • There are also some drugs that are used in animals that have no relevance in humans – they are not used in people and there’s no cross resistance with antibiotics that are used in people. They are largely irrelevant from an AMR standpoint (at least in terms of human health) but can skew the tonnage data for AMU in animals.
  • We need better metrics for measuring AMU and more thought and analysis than just looking at a single number. The easy sound-bite approach to data collection and dissemination isn’t really helpful.

There is now abundant research showing how this overuse of antibiotics in farming is a leading cause of “superbugs”, and that these superbugs are infecting workers and spreading into the food supply chain and our environment.

  • “A” is an important word here. Most AMR issues in humans relate to AMU in humans. At conferences, I’ve occasionally asked the audience “what percentage of AMR in people is likely attributable to AMR in animals?” I’ve gotten responses from 1-96%. It’s probably actually fairly low, but there are nonetheless some important issues there and AMU in animals is absolutely a contributor to AMR in people. How much of a contributor…? We don’t know.
  • So, AMU in farm animals is an important factor when it comes to AMR. However, it’s not an issue of addressing AMU in just farm animals. We need to address AMU in all sectors, including people. Failing to do that means we’ll never address the problem adequately.

Indeed, more than 100 Thais die every day because of superbugs. Yet even though the mortality rate is higher than COVID-19, there is almost a complete lack of awareness about this public health threat.

  • A great statement. AMR has been called the “silent pandemic.” It was well established before COVID-19, and it isn’t going away soon. Yet, people pay relatively little attention to it. Governments have less motivation to properly fund work on AMR and AMU, whether that’s research or stewardship initiatives. Canada has a framework for a national action plan for AMR that was released in 2017 and has been sitting on a desk for 5 years. We have a plan (that’s getting outdated) but no funding or action. So, we don’t have a plan, really.

Antibiotics are typically used at factory farms to either treat sick animals, promote their growth, or prevent disease. Fortunately, the use of antibiotics for growth promotion in several countries, including Thailand, has been bannedThe abuse of antibiotics in farming in Thailand is mostly to prevent stressed animals from getting sick due to farms’ poor welfare and management. The drugs are typically mixed with food and water and given across group herds. 

  • It varies by region, but there is definitely a large component of this in animal agriculture. Antibiotics can be used as a crutch to compensate for poor management, especially if antibiotics are cheaper and easier than good management or changes to things like animal housing.
  • As indicated, antibiotics aren’t used for growth promotion in many countries now. But, we need to increase that number. That’s relatively low hanging fruit. It just needs action at the national level in countries where antimicrobials are still used like this, and support for farmers to improve their practices so they don’t feel a need to use antimicrobials as growth promoters.

The root cause of the issue is the poor welfare in which farmed animals are kept in factory farms, and this must be addressed. Improvement in this area will support United Nations Sustainable Development Goal to ensure access by all to safe food. 

  • This is may be the most important statement in the article (although I’d remove the factory farm comment). As a member of the Global Leader’s Group on AMR, I bring this up repeatedly. We need to improve animal health systems to reduce the need for antimicrobials in animals, and to improve how they are used, when they are needed. Similarly, we need improvements in human health systems to optimize AMU in people. Healthier people and healthier animals need fewer antimicrobials.

Pig factory farms in Thailand are discharging huge quantities of pig waste (manure and urine), containing significant quantities of antibiotic-resistant genes and superbugs, into public waterways and the wider environment. 

  • AMR is a classic One Health issue, impacting human, animal and environmental health. Environmental impacts are often ignored, in part because they’re harder to see and understand. However, it’s impossible to argue that AMU in animals (and humans) doesn’t have profound environmental impacts. Some of those can come back to bite us too, as the environment can be a source of new resistant bacteria or resistance genes.

These findings by World Animal Protection also raise questions as to why superbugs from banned antibiotics can still be found in the environment near factory farms four years into the implementation of the national plan. 

  • Whether it’s in the environment, animals or people, changes in antibiotic use don’t instantly result in changes in resistance. It can take a long time to see changes, sometimes decades. We still see widespread chloramphenicol resistance in bacteria in livestock in Canada, despite the fact that this drug has been banned in food animals for decades. There’s no easy or quick fix for AMR. That’s why we need to focus on prevention and act now.

A ban on the preventive use of antibiotics in factory farms by increasing animal welfare standards would drastically reduce the presence of superbugs in our environment, but also guarantee safe meat for all. 

  • As with many things, a bit more nuance is needed. Bans aren’t the way out of the AMR problem. Reductions are (ideally massive reductions). Banning certain drugs and practices is reasonable. However, even well-raised animals (and people) sometimes need antibiotics. Sometimes, short courses of preventive treatment using lower-tier drugs are better for both health and AMR than needing to treat sick (or sicker) animals with other drugs, maybe for longer periods of time.
  • A lot of preventive use is unnecessary. Sometimes it’s done because of poor management. Sometimes it’s done because of inadequate education. Often it’s done because of historical reasons (“I’m doing this because that’s the way we’ve always done it and I’m afraid to make a change.”). Reducing AMU requires addressing all these factors, with improved health, improved education, access to better decision support mechanisms and addressing the social science components of AMU that are too often neglected.

This is a huge topic, and this long blog post can’t even start to do it justice. However, hopefully it raises awareness of some of the issues and highlights some of the complexities of the situation.

Everyone has a role to play in controlling AMR. It’s not just prescribers, farmers and regulators. It’s everyone involved in the chain of drug production to prescription to use to disposal. That’s pretty much everyone. The average person may think there’s little they can do, but there are lots of little things we can all do:

  • don’t press for antibiotics (for people or animals)
  • use antibiotics properly when prescribed
  • improve health of people, animals and the planet through other means (even small things)
  • call for change (give governments a reason to act)

That sounds a bit daunting, but for most people, it’s just little things, and lots of people doing little things can have a big impact.