Worrying new findings of antibiotic resistance in humans and livestock have prompted warnings the world is on the verge of a ‘post-antibiotic era’ unless steps are taken to address the problem.
A study in China found high levels of resistance to an important antibiotic, colistin, used to treat E. coli on farms and in human patients.
It has led to renewed calls for drugs used to treat humans not to be used in livestock.
The study, published in the Lancet, found resistance in E coli isolates collected from more than one on five, 166 out of 804, animals tested between 2011 and 2014.
Resistance was found in 15 per cent of more than 500 samples of raw meat tested.
It was also found in a small number, 16 out of 1322 samples equating to 1 per cent, of inpatients with infection.
The researchers said the emergence of MCR-1, the resistance mechanism identified in the study, ‘heralds the breach of the last group of antibiotics, polymyxins, by plasmid-mediated resistance’.
While resistance to colistin has been detected before, this study had prompted extra concern because of the way the mutation that causes the resistance is known to be easily shared between bacteria.
Although currently confined to China, they warned MCR-1 was likely to ‘emulate other global resistance mechanisms’ in spreading around the world. It could it previously treatable infection becoming untreatable.
“Our findings emphasise the urgent need for coordinated global action in the fight against pan-drug-resistant Gram-negative bacteria,” the researchers said.
Professor Timothy Walsh, who collaborated on the study, from the University of Cardiff, is reported to be meeting both the agricultural and health ministries in China this weekend to discuss whether colistin should be banned for agricultural use.
He told the BBC News website: "All the key players are now in place to make the post-antibiotic world a reality.
"If MRC-1 becomes global, which is a case of when not if, and the gene aligns itself with other antibiotic resistance genes, which is inevitable, then we will have very likely reached the start of the post-antibiotic era.
"At that point if a patient is seriously ill, say with E. coli, then there is virtually nothing you can do."
Professor Laura Piddock, from the campaign group Antibiotic Action, said the same antibiotics ‘should not be used in veterinary and human medicine’.
She told the BBC News website: "Hopefully the post-antibiotic era is not upon us yet. However, this is a wake-up call to the world."
A commentary in the Lancet said the implications of the study were ‘enormous’ and unless action is taken doctors would ‘face increasing numbers of patients for whom we will need to say, ’Sorry, there is nothing I can do to cure your infection’’.