How animal drugs are breeding superbugs and driving pandemic risk

Cows in Burgundy, France. (Credit Unsplah/Stijn te Strake)

Animals, not humans are the largest consumers of antimicrobial drugs – and thus the leading factor driving antimicrobial resistance. But WHO and other UN actors are still dancing around the "cattle, chickens and pigs" in the room. And member states aren’t keen to track animal antibiotic use trends – even at the cost of future health risks.

More than 73 per cent of all antimicrobial drugs sold in the world are used in animals. And more than human uses, the booming veterinary drug market is most probably the leading factor in growing antimicrobial resistance that is rendering common antibiotics and antiviral agents progressively more useless – also driving pandemic risks.

Even so, there is no systematic global tracking of drugs sold and used on animals as well as humans by the three big UN and multilateral organizations responsible, including the World Organization of Animal Health (OIE), the World Health Organization (WHO) and the Food and Agriculture Organization (FAO). Despite pledges to tackle pandemic risks and antimicrobial resistance (AMR) together, it’s unlikely such surveillance will begin anytime soon.

Meanwhile, around the world, veterinarians are making huge profits from selling animal drugs to farmers and thus driving their swelling use – particularly in India, China and other parts of Asia, said Thomas Van Boeckel of the Swiss Federal Institute of Technology Zurich (ETHZ) at a seminar on Achieving Sustainable Antibiotic Access using a One Health Approach on Tuesday.

“In 2017, about three quarters of all the antibiotics that we sold on this planet were used in animals, mostly to help them grow faster and to prevent infection,” Van Boeckel said at the Geneva Health Forum event.

“So in the context of development, if you see the emergence of new resistant genes, it’s like playing the lottery and losing, well, you have more chances to lose the [AMR] lottery in animals. And once they’re there [drug resistant microbes] they can eventually result in untreatable infections in humans if they’re transmitted.”

The ticking AMR time bomb no one is tracking

Van Boeckel and his interdisciplinary team, comprised of food scientists, ecologists, pharmacists and veterinarians, as well as disease modelers and epidemiologists from Brazil, China, and India as well as Europe and the United States, have mapped hundreds of studies to come up with an initial “heat map” of the world’s AMR hotspots. They are constantly developing that knowledge base on the open data site,

Mapping of AMR hotspots. (Credit: Thomas Van Boekel)

The group’s findings combine exhaustive data from animal drug sales, with reference to over 100 different types of antibiotics reported by countries – and mapped against livestock densities of cattle, chickens, and pigs.  They then compared that data with hundreds of local studies and reports of antimicrobial resistance, referring to major indicator bacteria, like E coli, Staphylococcus, Campylobacter, and salmonella.

Combined together, they yield a profile of the leading AMR hotspots across the world: The resulting “heat maps” demonstrate a clear correlation between drug overuse and drug resistance by mutating pathogens.

Their research relies upon hundreds of local studies on farms, markets and slaughterhouses, routinely done “by academics and veterinarians and microbiologists, who go out and look at what’s around their institute, to identify new resistant [pathogen] genes – something microbiologists like to do very much”.  But such studies typically are scattered across the literature and published in small journals that “hardly get any exposure”. Brought together, however, they provide powerful insights.

“One of the cool things is that you can zoom in to see where the problem is inside a country as well as the main regions identified as having high resistance,” said Van Boeckel.

Not surprisingly, most of the AMR hotspots are largely in the same places that have the largest use of antibiotics, per kilogram per meat, such as South India, South and Northeast China, and some parts of Latin America.

Trends in Asia are particularly worrisome since antimicrobial use for livestock and poultry is slated to grow even more across Asia in this decade, and represent two-thirds of the world’s veterinary consumption of antimicrobials by 2030.

“In 2017… the world used around 90,000 tons of antimicrobials in animals – at the time China was by far the largest consumer of antibiotics in animals,” reported Van Boeckel.

“By 2030, Asia will use more than two-thirds of the veterinary antibiotics in the world – while Africa will use only 6 per cent. So arguably, Africa has little responsibility for the state of resistance and AMR today,” he said.

“And in Europe and North America, we’ve had fairly high levels of antibiotic use over the last 20 years, but they are slowly declining, thanks to increased awareness about the need for stewardship in our farms.”

With the notable exception of Brazil, most of the 40 countries reporting systematically on veterinary antimicrobial use are major meat exporters, “which likely want to keep a good image in the securities export market”, said Van Boeckel.

But among countries producing meat mostly for domestic consumption, systematic national reporting is more sparse – and the researchers had to gather their data from a hybrid of commercial and research study sources.

Low and middle income countries failing to track AMR trends

Perhaps even more significantly, low and middle income countries are generally not tracking trends in AMR trends in livestock in any systematic manner, Van Boeckel pointed out.

Such surveillance is critical since the first sign of superbugs is likely to occur in and around animals, not people, given their role of animals as the world’s biggest antibiotic consumers.

“In Europe, we have systematic surveillance systems with a compelling metric for AMR for two to three decades, and we report this information at the national level,” Van Boeckel said. That surveillance eventually helped drive a wave of awareness and ultimately a European Union ban on the use of health promoting antibiotics in 2006.

Now, as the bulk of veterinary antibiotic use has shifted to low and middle income countries, “that’s really where the attention should be in the future”.

However, out of 135 low and middle income countries that the team explored, only Colombia had a government-run surveillance system that generates public data.

Pigs and chickens as superbug incubators

The team also has mapped trends by species. And that shows resistant pathogens increasing at a faster rate amongst pigs and chickens – whereas the prevalence of AMR amongst cattle is rising more moderately.

“Our goal for the next step is going to be to use that information to produce a global map of resistance levels across limited income countries. So concretely, we want to move from content information to continue continuous coverage of resistance level to do what some would call a heat map,” he said.

Superbugs increased almost 200% more in pigs and chickens than cattle. (Credit: Thomas Van Boekel)

One key factor driving trends are the financial incentives offered by animal health companies to veterinarians – which reap a hefty profit from selling more and more drugs to farmers with little knowledge of the products. They do so with minimal interference from governments, not only in Asia but also in some developed countries too, Van Boeckel says.

Another is the growing, and seemingly unquenchable hunger for more animal products in emerging economies as well as developed countries, which is the more fundamental driver of soaring livestock production, which in turn leads to more veterinary antibiotic use.

Van Boeckel compared the daily, per capita consumption of meat in Mali, which averages less than 27 grams a day, to that of China at 136 grams, and Australia at a whopping 260 grams. Those contrasts are captured in a series of photos that reflect a family’s typical weekly household food consumption across the three continents.

The photos reflect not only more meat, but also heavier consumption of ultra-processed foods and sugary drinks in emerging economies and developed ones – dietary trends that are simultaneously harming people’s health, the planet – and driving AMR.

A user fee for veterinary antibiotics?

Along with better tracking, global agencies need to be thinking about the kinds of policy solutions that would really bring the AMR under control, he stresses.  His team mapped out several key possibilities to project their results:

  • Regulatory action to reduce the use of antibiotics in livestock worldwide to 50 milligrams per kilogram of meat produced – roughly the European median – would reduce veterinary antibiotic use by 64 per cent.

  • Regulatory action among only OECD countries and China to do the same would lead to an almost equally sharp reduction in veterinary antibiotics of 60 per cent.

  • Consumer action to reduce meat consumption to just 60 grams a day – “about the equivalent of one Big Mac” – also would reduce antibiotic use in livestock by some 66 per cent.

“In other words, maybe we shouldn’t undermine the development of certain countries through livestock farming, as long as we have the OECD and China in the deal. We can make a significant difference,” says Van Boeckel.

Thomas Van Boeckel, of Zurich ETH, explains how soaring animal consumption of antibiotics, and human consumption of industrial meat, are the leading factors driving AMR (Credit: Health Policy Watch)

Yet another solution is to impose stiffer taxes, or user fees on antibiotics, which would in turn curb the incentives that now exist to farmers to purchase them at all – particularly when alternatives exist such as better sanitation practices, including more vaccination against preventable diseases.

One Health rhetoric, but little action

Such systematic global tracking of human and veterinary drug sales, and AMR trends should in fact be done by governments, and collected by the UN, Van Boeckel asserts.

But data on antimicrobial drug sales for human and animal use – and AMR trends in both populations – is not collated and reported systematically by the major UN and multilateral organisations responsible.

WHO, through its Global Antimicrobial Resistance and Surveillance System (GLASS), is trying improve surveillance of AMR in association with drugs used for human health, said Jorge Matheu Alvarez of WHO, who also appeared at the session. But tracking antibiotic consumption in animals or AMR in livestock isn’t really WHO’s job, he said.     

OIE tracks some data on veterinary use of antimicrobials, but that data remains very partial, with only 133 countries reporting to OIE at all. Many countries that do report lack data on actual quantities of antibiotics used or sold. In addition, the data is not transparent.  Some 71 per cent of countries that do report to OIE don’t make their data public. And therefore OIE’s data is presented only in terms of aggregate global quantities, rather by region or country.  No data on AMR trends in animals is published by the member state organisation. 

WHO, FAO and OIE have recently launched a new one health collaboration together with the UN Environment Programme.  Both FAO and OIE have included antimicrobial stewardship in the animal sector in their global action plans, Alvarez noted saying: “We are making progress in the collaboration in these one health areas.”

Alvarez says FAO, OIE and WHO will soon begin placing the surveillance data they do collect on a single platform, called the Tripartite Integrated Surveillance System on AMR (TISSA).

“Here we will host the one health information collected by the different organizations on AMR, antimicrobial consumption and use of antimicrobials,” he told Health Policy Watch.

But animal and human data thus collected won’t likely be reported and presented in a comparable manner for some time to come, he admits, because of different data collection methods.

Member states are highly resistant to reporting on their antibiotic drug sales and consumption because they see it has implications for their global trade in meat, the panelists also noted.

“We need to be clearer and provide more guidance in the animal sector,” Alvarez told the panel session. It was hosted by the Global Antibiotic R&D Partnership (GARDP), which aims to accelerate the development of new antibiotic treatments for drug resistant infections and also attended by the Foundation for Innovative New Diagnostics (FIND), which is ramping up the development and deployment of infection tests to reduce unnecessary use of antibiotics in humans.

Van Boeckel said: “I’ve been in this field for about ten years, and I thought something would have happened by now. I’ve been expecting a globally harmonised AMR surveillance system by the FAO and OIE that reports that data. And I can only ask the question, why hasn’t that happened?”

Until those agencies, and the member states that control them, rise to the challenge, surveillance of critical AMR trends will likely remain the purview of research teams such as Van Boeckel’s.  But meanwhile, the neglect of animals’ antibiotic consumption remains just another pandemic waiting to happen.

“If we want to inform policy in the short term, we need an alternative systematic surveillance system for LMICs, where we’ve seen that conditions may unfortunately be the worst, when it comes to development of resistance, in the coming decades,” he warned.

This story appeared first on Health Policy Watch.