Antibiotic resistance: What is a superbug?

The world is on the cusp of a "post-antibiotic era", scientists have warned after finding bacteria resistant to drugs used when all other treatments have failed.

Doctors identified bacteria able to shrug off the drug of last resort - colistin - in patients and livestock in China.

Bacteria becoming completely resistant to treatment - also known as the antibiotic apocalypse - could plunge medicine back into the dark ages.

BBC Online Health Editor James Gallagher explains what Thursday's warning means - and the potential impact of a so-called superbug.