Aoife McLysaght: Post-antibiotic era will bring us back to the ‘dark ages’

19 Nov 2015

It sounds post-apocalyptic, but we appear to be on the brink of moving into the post-antibiotic era where common diseases become untreatable, with a bacteria that is resistant to all antibiotics having just been discovered.

The ushering in of the post-antibiotic era is widely considered a matter of when, not if, with this recent discovery showing that, because of the overmedication of livestock in China, a bacteria that is resistant to our last line of antibiotic defence, colistin, exists.

According to the BBC, Chinese scientists discovered the mutated gene, MCR-1, which is totally resistant to colistin and, in a report in the journal Lancet Infectious Diseases, found resistance in 15pc of the samples of raw meat analysed.

Not only that, but this mutated gene has been found in other bacterial strains, including E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, all discovered in China, Laos and Malaysia.

One of Ireland’s leading geneticists, Prof Aoife McLysaght, has been one of the most prominent people speaking of the inevitability of the onset of the post-antibiotic era and, in conversation with, explained how this strain came about.

Bring us back to the dark ages

“The resistant bacteria were identified in farm animals where antibiotics are often used pre-emptively (ie not only in case of infection) and they use the same antibiotics as in human medicine,” she said.

“This creates a selection pressure on bacteria to evolve antibiotic resistance. And we already know that evolution by natural or unnatural (as in this case) selection is very powerful. If there are no effective antibiotics then we are back to the dark ages of people dying of ‘ordinary’ infections.”

When asked whether this could have been avoided, ultimately, she said yes and even suggested that if we’re lucky it could be limited if we act immediately.

“[Not using colistin on animals] would have helped – and perhaps still could – but also limiting antibiotic use to cases of veterinary need. [Antibiotics are used] in some countries, including the US, just to maximise growth.”

If there is indeed any sense of hope, at the beginning of the year reported on the discovery of a new potential antibiotic called teixobactin, which was the first discovery of any form of antibiotic in three decades.

The study that found this resistant bacteria said that the “implications [of this study] are enormous” adding fear that we “face increasing numbers of patients for whom we will need to say, ‘Sorry, there is nothing I can do to cure your infection’.”

Sick couple in bed image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic