The booming use of antibiotics and other antimicrobial agents in farming is giving rise to resistant bacteria
By
A world where common infections are untreatable is no longer a remote possibility; we already live there. In 2019, more than 1.2 million people died as a direct result of antibiotic-resistant bacterial infections; a number that is expected to rise to ten million by 2050. Yet, while the dangers of antimicrobial resistance have been known for some time, we’ve been slow to act. According to the Global Leaders Group on Antimicrobial Resistance (GLGAMR) – a collection of world leaders and experts working to accelerate action on antimicrobial resistance – we’ve left ourselves a ‘narrow window of opportunity’ to avert a looming crisis.
Antimicrobial agents, often shortened to antimicrobials, are a broad category of substances (which include antibiotics) that are used to kill or inhibit the growth of microorganisms such as bacteria, viruses and fungi. The World Health Organization calls them the ‘cornerstone of modern medicine’.
Over the last few decades, however, the demand for antimicrobials has soared – particularly in farming, where, in addition to treating sick animals, they’re often used prophylactically (to prevent animals from getting sick in the first place) and as livestock ‘growth promoters’. This excessive use has given rise to antimicrobial-resistant bacteria, which have spread through the food chain, jeopardising the effectiveness of antibiotics in treating human infections.
In many countries, antimicrobial use in agriculture now surpasses human consumption. A 2017 study led by researchers at the One Health Trust found that globally, 73 per cent of all antimicrobials used that year had been administered to livestock. In response, the GLGAMR is calling for a 30–50 per cent reduction in agricultural antimicrobial use by 2030 and the complete eradication of medically important antibiotics in healthy livestock and in crops.
To date, there has already been some progress towards a reduced reliance on antimicrobials in farming. In 2022, following a ban on the routine use of antibiotics in healthy livestock, or to compensate for poor hygiene and animal husbandry practices, farm antibiotic sales fell by 12.7 per cent across 31 EU countries.
However, the picture isn’t universally positive. In low-and middle-income countries (LMICs) a booming demand for meat, fuelled by growing populations and rising incomes, is driving an increase in intensive livestock production. This, in turn, fuels the need for antimicrobials to prevent disease outbreaks and maintain productivity. As a result, experts estimate that global antibiotic use is set to increase by eight per cent by 2030, with the largest increase expected in LMICs such as Pakistan, where nationwide use could rise by as much as 44 per cent.
Some experts are worried that the current suggested global targets for tackling antimicrobial resistance are unrealistic for many LMICs. ‘If the target is too ambitious and is to be delivered in too short a timeframe, some countries will ask, “Why bother?”’ says Timothy Walsh, director of biology at the Ineos Oxford Institute for Antimicrobial Research.
In addition to more realistic reduction targets, Walsh says there’s a need for sustained financial support for the countries facing the biggest obstacles to reaching those targets, to help them to implement different disease-prevention strategies. ‘While we urgently need to reduce the amount of antibiotics used in agriculture, we cannot expect farmers to do this without providing alternative solutions,’ he says. ‘A ban without alternatives will lead to a decrease in meat production, to price increases and a loss of income for farmers. If we do not address the bigger picture, such targets will result in an increase in global poverty.’
In Pakistan, the world’s third-largest dairy producer, nearly half the country’s workforce is employed in agriculture. The country’s dairy farmers face a number of challenges, from hot weather to a lack of access to better farming practices and veterinary services, and anecdotal evidence suggests that antimicrobial resistance is on the rise in their livestock. At the Sustainable Development Study Center in Lahore, researchers found that while 60 per cent of local dairy farmers were aware of the risks associated with antibiotic misuse, more than 90 per cent reported that the cost of completing an antibiotic course was prohibitive, and they often kept them for future use or to share with friends and family.
While many of the tools to tackle antimicrobial resistance already exist – vaccination programmes and better animal husbandry practices can significantly reduce the need for antibiotics in the first place – many countries will need support to access them. Walsh adds that while many high-income countries have reduced their own use of antibiotics in farming, paradoxically, they’re still exporting drugs such as colistin (a last-resort human antibiotic) to LMICs. The GLGAMR puts the current cost of such support at US$46 billion per year. However, without swift action, it’s estimated that the rise of antimicrobial resistance could drive up global healthcare costs by US$412 billion a year as early as 2035.
