University of Oxford, Africa, Asia
24 July 2024
A new study from the University of Oxford reveals that the widespread use of the antibiotic colistin to prevent infections and promote growth in animals raised for human consumption, such as poultry, is leading to significant consequences.
Colistin is one of the few remaining antibiotics used as a last resort to treat multi-drug-resistant infections, including pneumonia, and is deemed critically important for human medicine by the World Health Organization.
The research, led by scientists from the University of Oxford, UK, and the University of Agriculture Faisalabad in Pakistan, found that despite colistin’s ban in agriculture in many high-income countries, including China and several European nations, these countries still export colistin to low- and middle-income countries such as Pakistan, Nigeria, and Bangladesh.
This international study is a collaboration between the University of Oxford, University of Agriculture Faisalabad, the National Institutes of Health in Pakistan, Ahmadu Bello University in Nigeria, Dhaka Medical College Hospital in Bangladesh, and Cardiff University.
Despite global agreements to limit antibiotic use in agriculture, the lack of regulation at the commercial and national levels means that colistin is still widely used in countries where alternative treatments are expensive or inaccessible. The study also identified a range of colistin products manufactured for pediatric use and marketed as ‘Antibiotic – Anti-Diarrhea.’
Researchers identified an increasing rate of colistin-resistant E. coli isolated from the environment and food-producing animals in Pakistan, with 7% of samples compared to the global average of 4.7%. Resistance was also observed in human isolates.
Professor Timothy Walsh, Director of Research at the Ineos Oxford Institute for Antimicrobial Research and co-lead author of the study, stated, “The use of human antibiotics in animal feed is one of the biggest drivers of antibiotic resistance globally. While many high-income countries have reduced antibiotic use in livestock, paradoxically, they still export drugs like colistin to low- and middle-income countries. We need to stop using human antibiotics in animal feed. Reducing meat production, increasing prices, and causing farmers to lose income. One of our main focuses at the Ineos Oxford Institute is developing new drugs that can be used exclusively in animal feed, as well as helping farmers improve farm hygiene and protect animal welfare to reduce dependence on human antibiotics.”
The extensive study, published in The Lancet Microbe, indicates that farmers using these drugs have limited understanding of the consequences of colistin use and underscores the importance of supporting farmers in making sustainable improvements, including better hygiene in their farming practices.
Dr. Mashkoor Mohsin of the University of Agriculture Faisalabad, Pakistan, co-lead author of the study, said, “We need to change the way antibiotics are produced, traded, licensed, and used for veterinary purposes. At the same time, we cannot overlook the welfare of animals and the livelihoods of farmers in countries like Pakistan and Bangladesh. Such global change will require significant commitment from national governments, financial institutions, pharmaceutical companies, and international trade regulators.”
Translated by Võ Văn Sự from: University of Oxford, Africa, Asia. 24 July 2024. “Use of colistin in animal feed is increasing antibiotic resistance amongst humans.” Source