Antibiotic use is a collective agreement: we all remain safer so long as everyone follows a set of common rules.
Four years ago, a group of scientists conducting a routine study at a farm in Shandong, eastern China, found something they weren’t supposed to. In a sample obtained from an apparently healthy pig, the researchers discovered a new gene located on a strain of e-coli bacteria that was resistant to colistin, the world’s antibiotic of last resort. It had never been seen before.
If you’ve got a stubborn infection that refuses to heed all other drugs, colistin is your last bet. Its status as an antibiotic of “last hope” is why doctors are parsimonious and precise about prescribing it. No new antibiotics have been discovered for treating the infection that colistin can be used upon, and the European Medicines Agency says the prospect of discovering alternatives in the near future is “limited”.
So it was a grim surprise when scientists discovered the resistant gene had travelled to chickens, too. “We’d known there were colistin resistant bacteria for some time, but the difference with this one was that it was mobile – it could spread – from poultry, to humans,” Timothy Walsh, a professor of microbiology at the University of Cardiff and honorary chair at the Chinese Agricultural University, tells me over the phone. “We realised it was a tsunami coming our way.”
Antibiotic resistance, where a microbe mutates or develops a gene that resists antibiotic treatment, is one of the greatest threats to human life. Already in Europe an estimated 33,000 people die each year from antibiotic-resistant infections. The UK’s chief medical officer Sally Davies has described the threat as a looming “apocalypse” that could wipe out humanity before climate change does – and has called for an Extinction Rebellion-style campaign to meet the challenge of antibiotic resistance. If bacteria become resistant to drugs like colistin, we will return to a pre-penicillin age; simple infections will become fatal, and routine operations like hip replacements and caesareans impossible.
These rare drugs are being willfully squandered for profit. Livestock farmers often use antibiotics across entire herds – not to cure illness, but to prevent it. Chinese farmers had been dousing animal feed with colistin to artificially fatten pigs, a practice that has been illegal in the EU since 2006 (one of the side effects of dosing animals with antibiotics is enhanced growth). Once scientists discovered the resistant gene among pigs and poultry, they successfully pressured China’s government into banning the drug in animal feed. “We now remove 8,000 tonnes of colistin from Chinese agriculture every year,” Walsh tells me.
When antibiotics are used in farming, they diffuse into the atmosphere through water and slurry, making the surrounding environment into a reservoir for residues, resistant pathogens and antimicrobial properties – a toxic soup with unpredictable effects for human bodies. Though the World Health Organisation has urged governments to restrict colistin use to people, British farmers are still …read more
Source:: New Statesman