LONDON: Canadian pop singer Justin Bieber is showing early signs of making a recovery after he was diagnosed with a virus that left half of his face paralysed, according to a surgeon who specialises in face paralysis.

In a video posted on Instagram, Bieber said he had contracted Ramsay Hunt syndrome, which affected nerves in his ear and face. He noted that his right eye was not blinking.

Charles Nduka, a consultant plastic reconstructive surgeon in Britain and the co-founder of health charity Facial Palsy UK, said about 75% of patients with the syndrome who receive early treatment, including steroids and antivirals, make a full recovery.

"I did notice in the video shared by Mr Bieber that he does appear to have some evidence of recovery, which is encouraging," Nduka told Reuters.

"With facial paralysis one of the most obvious things is patients are unable to close their eye fully to blink and they are unable to smile," Nduka added.

"Before the smile recovers, the first thing that will develop is there is increasingly symmetry in the face at rest. So, the base of the nose often elevates slightly, and the mouth becomes more even. On the video that was shared I could see some signs that there is some early recovery."

Bieber, 28, said he was physically unable to perform his upcoming shows.

Nduka said he works with patients in the entertainment industry and it is important they first address any issues weakening the immune system before returning to work.

"They will be under financial pressures and all sorts of pressures to get back out there as soon as possible, but doing so will only lead to longer term problems," he said.