Our antibiotics are failing us. In 2025, the UK Government said antibiotic resistance (AMR) contributes to more than 35,000 deaths each year in the UK. Emergency doctors say they are losing patients on a regular basis when they run out of ways to treat them.

Antibiotics have saved countless lives, but alongside them, there is another unlikely sounding ally in this fight: viruses, so small that they can attack and kill the bacteria causing these devastating infections. They are called bacteriophages, or phages for short. There are more of them than any other commonly occurring natural entity on the planet. And we could be about to see doctors using them on very ill patients in the UK. The thing is scientists have studied bacteriophages for nearly a century. They are used routinely in other countries, and science journalist Marnie Chesterton, who has been following this story for nearly a decade, asks why, suddenly, is phage all the rage?