A gene which helps bacteria resist the only antibiotic group that works when all others fail has been discovered by Chinese and British scientists.
Antibiotics were the seminal breakthrough of medical science, revolutionizing medical care in the 20th century. For a few decades (between the 1950s and 60s whole classes of new antibiotics were discovered) new strains of antibiotics were discovered faster than bacteria could adapt to them. This trend has since reversed, with no new classes discovered for the three decades between the 1980s to 2000s and only one class discovered just this year (2015).
On the cusp of the new millennium, the BBC cited a report made by The Standing Medical Advisory Committee: “In the closing years of the century, there is an uneasy sense that micro-organisms are ‘getting ahead’ and that therapeutic options are narrowing“… a prediction which will turn out to be true.
UK specialists from Bristol and Cardiff have worked together with Chinese doctors to publish their research on the Lancet Infectious Diseases journal.
Their conclusions aren’t particularly pleasant, as they predict a return to the Dark Ages where even contraction of common diseases could prove fatal.
“These are extremely worryingly results,” professor and co-author on the study Liu Jian-Hua, from China’s Southern Agricultural University, said in a press release.
The researchers examined Chinese farms, believing that bacteria with increased resistance could be spawned there.
They discovered MCR-1 (three letters and one digit have never been so terrifying) the gene which allows common bacteria to develop resistance to polymixins- an antibiotic that we rely on to combatsuperbugs.
E. Coli and K. Pneumoniae are relatively common bacteria, and this is where MCR-1 was detected by the scientists. The gene is also easily spread between strains, allowing faster adaptation.
“The polymyxins (colistin and polymyxin B) were the last class of antibiotics in which resistance was incapable of spreading from cell to cell,” the author explained further. “Until now, colistin resistanceresulted from chromosomal mutations, making the resistance mechanism unstable and incapable of spreading to other bacteria.
“The emergence of MCR-1 heralds the breach of the last group of antibiotics,”Liu continued. “Although currently confined to China, mcr-1 is likely to emulate other resistance genes … and spread worldwide. There is a critical need to re-evaluate the use of polymyxins in animals and for very close international monitoring and surveillance of mcr-1 in human and veterinary medicine.”
“This is a worrying report, as polymyxins are often the last resort antibiotic to treat serious infections,” Laura Piddock, professor of microbiology at the University of Birmingham, said, according to AFP. “Equally worrying is that this type of resistance can be easily transferred between bacteria.” And according to Piddock, the spread could mirror other drug resistance mechanisms, such as that of tuberculosis.
Chinese farms often use Colistin, and bacteria with the MCR-1 gene were found in pigs, chickens andpeople in South China. This is by no means an isolated problem; factory farms around the world have been known to use all manner of antibiotics on their animals as an easy method of increasing their profits at our expense… and the US FDA has been accused of ignoring antibiotic use in animals.
The gene was discovered accidentally; lab results from patients of two hospitals were matched with routine test results taken from pigs and chickens that had been in contact with the individuals.
“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,“ Professor Timothy Walsh of the University of Cardiff, who collaborated on the study, told the BBC News.
“At that point if a patient is seriously ill, say with E. Coli, then there is virtually nothing you can do.”
“The finding that this type of resistance can be shared by different bacteria – irrespective of whether from food, an animal or a person – is further evidence that the same drugs should not be used in veterinary and human medicine,”said Piddock.