Are viruses the key to fighting infections?

Yes and no. There are some viruses that are solely designed to fight bacterial infections, called bacteriophages (phages). These viruses attach to bacterial cells and inject their genome into the cell. The bacteria then produces the viral genome instead of its own, and this interferes with its ability to function, effectively halting the bacterial infection.

There are thought to be billions of phages on Earth; they have co-evolved with the bacteria they prey on for millennia, keeping their numbers under control.

Phage therapy is the use of active phages to kill bacteria that cause human diseases while leaving other bacteria unaffected. Phages have been around for a long time – they were officially discovered in 1915-17 and they have been used ever since as therapeutics, especially in countries like Russia, Belgium and Georgia. The reason why phage therapy was abandoned was mostly because of the discovery of antibiotics. But now there is a lot of hope that phages could help to destroy antibiotic-resistant strains of some of the most resilient superbugs in existence.

However, there are several obstacles to using phage therapy more widely. Phages are specific to particular bacteria, and those bacteria can evolve resistance. And it is proving challenging to recreate the way viruses behave in the body in lab environments. However, it is an exciting field to watch out for, and research is evolving to explore potential applications.

Time will tell whether these viruses are the key to fighting infection.

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Dr Nish Manek is a GP in London. She completed her medical degree at Imperial College and was runner-up in the University of London Gold Medal. Manek has also developed teaching courses for Oxford Medical School, and has penned articles for The Guardian and Pulse magazine.