Tiny hitchhikers on viruses could promote resistance to antibiotics

FROM caesarean sections to chemotherapy, antibiotics make much of modern medicine possible by keeping bacterial infections at bay. That is why the growing bacterial resistance to those drugs is so worrying. The United Nations estimates that by 2050 infections with drug-proof bacteria could claim up to 10m lives a year, more than double the current toll.A problem with tackling such resistance is that scientists have an incomplete sense of how it arises. One way is essentially random: a chance mutation in a particular bacterium may make a certain drug less lethal. If that bacterium survives a dose of treatment, its descendants will inherit that same resistance. But the speed at which bacterial drug resistance spreads means that cannot be the whole story. “I always felt there were additional mechanisms of evolution. And probably more powerful ones,” says John Chen at the National University of Singapore.