Former Formula One world champion Niki Lauda has returned to intensive care five months after undergoing a lung transplant, Austrian media sites reported Sunday.
Lauda, 69, is reportedly suffering from flu and has been transferred to hospital in Vienna where he was previously treated in the summer.
Austrian publication Oesterreich reported on its website that Lauda was flown back to his home country from the Spanish island of Ibiza, but the website also suggested he could be released from hospital next week.
Lauda was seriously injured in a crash at the Nurburgring in 1976 which left him with severe burns to his head and damage to his lungs and blood.
He was taken ill at the beginning of August and his condition was described as 'extremely critical' at the time of surgery.
The airline entrepreneur and Mercedes non-executive chairman had been hoping to return to the paddock for the season-opening Australian GP in Melbourne on Mar. 17 as he gradually recuperated from the complicated operation.