Veterinarian preparing injection to piglet on farm

Research carried out by a UK-China collaboration played a key role in the introduction of a ban on the use of the antibiotic colistin as a feed additive for animals in China.

The Chinese Ministry of Agriculture’s ban was supported by the work of a team led by Professor Jianzhong Shen, of the Beijing Advanced Innovation Center for Food Nutrition and Human Health at China Agricultural University, Beijing, in collaboration with Professor Timothy Walsh, of the School of Medicine at Cardiff University, and Dr Jian-Hua Liu of South China Agricultural University in Guangzhou, China.

In 2015, the team identified a gene called MCR-1 that allowed bacteria to survive colistin treatment in animals and humans in China. MCR-1 is a ‘mobile gene’, meaning that it can be easily transferred to other bacteria, making them resistant too, and the team identified the gene in a strain of bacteria called Escherichia coli found in pigs.

Colistin is an important ‘last resort’ antibiotic, used to treat serious bacterial infections in humans resistant to other antibiotics. It is also used in animal feeds to help rear healthy animals but widespread use of the antibiotic encourages the development of resistance genes.

Following their discovery, the team worked with the Chinese Government to investigate the impact of MCR-1 on colistin use in animals and humans.

Newton funding helped them to continue the work and the immediate implication was the withdrawal of more than 8,000 tonnes of colistin as a growth promoter from the Chinese veterinary sector, which will be replaced by other non-human antibiotics, supplemented by traditional Chinese medicines.

The European Medicines Agency has also taken steps to update its advice on reducing the use of colistin in European veterinary practices.

Professor Jianzhong Shen said: “Antibiotic usage in food animals is becoming a global issue associated with food safety and public health. All countries in the world should use antibiotics in animals more prudently and rationally.

“On the basis of the evaluation of risk assessments of such antibiotics, the Chinese Government worked promptly to remove colistin in the list of feed additives for the purpose of growth promotion.”

Professor Timothy Walsh said: “This is a remarkable example of how scientific discoveries can positively impact on animal and human populations.”

The work was mainly funded by the National Key Basic Research Program of China and the National Natural Science Foundation of China, with additional support from the UK Medical Research Council (MRC).

Dr Jonathan Pearce, Head of Infections and Immunity at the MRC, said: “Antimicrobial resistance (AMR) poses a global challenge to healthcare and agriculture. Our response to this challenge must span nations and disciplines.

“By pooling our research efforts, we can develop a deeper understanding of the drivers of AMR. Through collaboration with society, industry and policy makers, we can apply this knowledge to turn the tide against the AMR threat.”