Austrian said last month that his operation was worse than when he was badly burned in 1976 in a Formula One crash
Formula One legend Niki Lauda is back in hospital in Vienna with the flu, five months after undergoing a lung transplant.
Lauda, 69, was flown in early January from the Spanish island of Ibiza, where he had been on holiday, to a hospital in the Austrian capital.
Oesterreich report that Lauda was in intensive care, but should be released from the hospital later this week.
Last month Lauda has claimed undergoing the op in August was worse than his infamous Nurburgring crash.
The Austrian revealed he was in constant contact with Lewis Hamilton from his hospital bed as the British superstar won his fifth world title last month.