October 21, 2019


Antibiotic resistance in livestock close to tripling, report states


Antibiotic use in livestock have spiked due to the rising consumption of animal proteins in developing nation, consequentially leading to a near tripling of antibiotic resistance, a recent report in the journal Science stated. 

Using close to 1,000 publications and unpublished veterinary reports from around the world, researchers from ETH Zurich, the Princeton Environmental Institute (PEI), and the Free University of Brussels were able to create a map of antimicrobial resistance in low- to middle-income countries.


The report puts the spotlight on the bacteria Escherichia coli, Campylobacter, Salmonella and Staphylococcus aureus - serious disease that affect both animals and humans.


Between 2000 and 2018, the proportion of antibiotics showing rates of resistance above 50% in developing countries increased in chickens from 0.15 to 0.41 and in pigs from 0.13 to 0.34, the researchers reported. This means that antibiotics purposed for treatment failed more than half the time in 40% of chickens and one-third of pigs raised for human consumption.


The researchers found that antibiotic resistance in livestock was most widespread in China and India, with Brazil and Kenya emerging as new hotspots. Since 2000, meat production has grown by more than 60% in Africa and Asia, and by 40% in South America, as countries on those continents shifted from low- to high-protein diets. More than half of the world's chickens and pigs are in Asia.


"This paper is the first to monitor antibiotic resistance in animals globally and it finds that resistance has gone up dramatically during the past 18 years," said Ramanan Laxminarayan, co-author and senior research scholar of PEI.


The research was supported by the PEI Health Grand Challenge programme and included co-author Julia Song, a graduate of Princeton's Class of 2018 and a past PEI research assistant.


"We certainly do want higher-protein diets for many people, but if this comes at the cost of failing antibiotics, then we need to evaluate our priorities," Laxminarayan added.


Meat production accounts for 73% of global antibiotic use. Antibiotics have made large-scale husbandry and widespread meat consumption possible by reducing infection and increasing the body mass of livestock.


The skyrocketing emergence of antibiotic resistance in livestock is especially troubling in developing countries, said the report's author Thomas van Boeckel, an assistant professor of health geography and policy at ETH Zurich. Those nations continue to experience explosive growth in meat production and consumption, while access to veterinary antimicrobials remains largely unregulated.


The researchers suggest that developing nations should start restricting the use of human antibiotics in farm animals. In addition, affluent nations should support a transition to sustainable farming, possibly through a global fund to subsidise biosafety and biosecurity improvements.


- News-Medical.Net