Doctors taking care of triple Formula 1 world champion Niki Lauda have given a positive update on his recovery after undergoing a lung transplant.

The Austrian, who now sits as non-executive chairman at Mercedes, was notably absent from the final two races before the summer break after falling ill on holiday from what was believed to be a severe case of summer flu.

After flying home, it was later diagnosed as a serious lung disease resulting in the successful transplant which took place late last week.

“Everything is currently going very well and we are very satisfied,” confirmed the head of thoracic surgery at the Vienna hospital where Lauda was treated.

“Considering the not very easy circumstances we are very, very happy with the developments."

The news also came around the 42nd anniversary of Niki's infamous crash at the Nurburgring in 1976 which left him with severe burns and lung damage after inhaling the smoke and other fumes from his fiery Ferrari.

Unsurprisingly, the question was asked if there was a link.

“One can absolutely assume that lung transplantation is not a late consequence of the fire accident,” he said.

Writing on Twitter before signing off for the summer break, Mercedes motorsport boss Toto Wolff paid tribute to the 69-year-old.

"The world knows Niki as an F1 legend with incredible power and resilience, for all of us at Mercedes he is our chairman, our mentor and our friend," he said.

"We have missed him by our side in Hockenheim and Hungary, and can’t wait to have him back with us.

"The recovery he faces is not a race, but I’m sure he will soon be telling every nurse and doctor that he has had enough of hospital.

"We wish him a safe and speedy recovery – in that order – and send all our positive energy to him and his family.

"I miss you my friend," he added.

Doctors believe it could around a month before Lauda is back at full health.