Antibiotic-resistant superbugs are springing up in farms around the world, the direct result of our overconsumption of meat, with potentially disastrous consequences for human health, a study has found.
Areas in north-east India, north-east China and the Red River delta in Vietnam were identified as hotspots in Asia, with areas as widely separated as Mexico and Johannesburg also affected. But the hotspots are expanding quickly. The study found areas where resistance to antibiotics among farm animals was starting to emerge in Kenya, Morocco, Uruguay, southern Brazil, central India and southern China.
The scientists said there was a “window of opportunity” to limit the rise of resistant bacteria “by encouraging a transition to sustainable animal farming practices” around the world, particularly in the countries highlighted.
“Regions affected by the highest levels of AMR [antimicrobial resistance] should take immediate actions to preserve the efficacy of antimicrobials that are essential in human medicine, by restricting their use in animal production,” the authors said.
They called the rise in demand for meat “the most notable dietary trend of our time”, with demand rising by nearly 70% in Asia alone since 2000. But as the demand is being met from highly intensive farming, often with animals raised in poor conditions, it has fuelled the use of antibiotics, used in many countries to keep the livestock healthy and promote faster growth.
This overuse leads to the development of superbugs that are resistant to key medicines, which is likely to spread from the hotspots already identified, with “potentially serious consequences for public health”
China and India are home to more than half the world’s pigs and chickens, but controls on antibiotic use in farming are lax. Nearly three-quarters of the antibiotic medicines used in total around the world are used on animals grown for food, and growing resistance to such medicines is breeding superbugs that can transfer to humans. The study shows the proportion of pathogens infecting farmyard chicken and pigs that were “significantly resistant” to antibiotics rose between 2000 and 2018.
Coilin Nunan, the scientific advisor to the Alliance to Save Our Antibiotics, said the study raised “serious concerns” about global meat consumption and the intensification of livestock farming.
“The increases in antibiotic resistance in developing countries are significantly higher in pigs and poultry than cattle, consistent with the greater intensification of farming practices,” he said. “There are also far more hotspots found in Asia where livestock is more intensive than in Africa where meat consumption is generally low. But even in Africa livestock farming is gradually intensifying and the study found emerging hotspots.” He added, “If the government decides to cut tariffs on imported meat, there could be an increase in imports from countries where there are low animal-welfare standards and weak or non-existent regulations on farm antibiotic use.”
Catrin Moore, of the Big Data Institute in Oxford, said internationally coordinated action was needed. “There needs to be a number of measures taken concurrently, such as new antibiotics being developed, a good diagnostic tool to determine the infectious agent [when livestock fall sick], and resistance information to target the infection rather than using prophylactic antibiotics,” she said. “Plus stopping the use of antibiotics as growth promoters, and their use prophylactically.”Kristen Reyher, a reader in veterinary epidemiology at the University of Bristol, who was not involved in the study, said: “This highlights the importance of monitoring and surveillance of antimicrobial-resistant pathogens and antimicrobial use, in both human and animal populations. It is crucial to understand the reasons why these medicines are used in livestock systems, to address the drivers for use and transmission of antimicrobial resistance.”