As concern about resistance to antibiotics grows a new type of therapy could prove vital.
When British 17-year-old Isabelle Carnell-Holdaway contracted a life threatening infection she was given a carefully selected cocktail of viruses to infect the bacteria that would've otherwise killed her.
She was given a less than 1 per cent chance of survival by doctors at Great Ormond Street Hospital who decided to use the untested "phage therapy" on her.
Now, the BBC reports that Isabelle is "learning to drive and studying for her A-levels."
The treatment was so successful health professionals are now looking at how to treat other dangerous infections with phage therapy.
Watch the BBC report above to find out more about the groundbreaking treatment that saved Isabelle's life.