— End of one era, dawn of another
WE’RE NEARING THE end of the antibiotic era. Ever since penicillin became widely available after 1945, people stopped worrying about infections. Sore throats or infected cuts were quickly sorted out by antibiotics from a kindly doctor followed by a few days in bed. Later generations quickly forgot that simple infections could be deadly.
Antibiotics were such a wonderful cure-all that doctors prescribed them with abandon, like sweets. They weren’t just good for curing infections in people: they also had a surprising side effect as growth accelerators for chickens, pigs and cows. As a result, antibiotics have flooded our environment. This has killed off a lot of microbes, but left room for their antibiotic-resistant relatives to thrive. It’s a textbook example of evolution: when the environment changes, the fittest individuals gain the upper hand and multiply.
The ranks of antibiotic-resistant microbes have now swelled dramatically. You might encounter a resistant strain of golden staph during routine surgery in an Australian hospital, or a trip to New Guinea might land you with a multidrug-resistant strain of tuberculosis.
In 2016, the UK government commissioned economist Jim O’neill to measure the scale of the crisis. He found 700,000 people die each year due to infections by drug-resistant microbes. By 2050, that figure will rise to 10 million if nothing is done.
One response is to try to turn the tables on the enemy by taking away its selective advantage. By slowing the tap that drips antibiotics into the environment, particularly into farm animals, we can make life easier for antibiotic-susceptible microbes, which should slow the advance of the resisters.
Meanwhile, we are in dire need of a new generation of weaponry. Our lead story this issue takes a look at what’s in the pipeline. One approach looks back in time.
Penicillin was developed in response to the crisis of the Second World War. But the First World War had led to another antibacterial treatment: like fleas that have littler fleas on their backs to bite ’em, bacteria themselves are prey to tiny viruses called bacteriophages.
Bacteriophage therapy was superseded by the use of penicillin and other antibiotics, which was easier to industrialise. But Eastern European countries have continued to use bacteriophages to treat infections. Because phages can outcompete bacteria in the evolutionary arms race, they are an important weapon to which many Western researchers are now returning.
Others are exploring new strategies. These include “defanging” disease-causing bacteria without killing them, using a deadly phage extract called lysin as a drug, or stopping overgrowth in bacterial ecosystems using compounds called “quorum quenchers”.
We’re witnessing the birth of a smart new arsenal designed with an eye to being evolution-proof. Gain hope from reading Dyani Lewis’s report.
ELIZABETH FINKEL Editor-in- chief