The Duke of Edinburgh spoke briefly about his health on Wednesday morning as he officially opened the Francis Crick Institute – alongside Her Majesty The Queen.
When touring the new £650 million biomedical research centre, the 95-year-old Duke said that he hadn’t suffered from the flu in over 40 years.
The Duke made the revelation after speaking to flu immunity to expert Dr Yi Pu Lin.
Prince Philip asked Dr Lin if it was possible for somebody to develop an immunity to the flu, and asked: “Why haven’t I had flu for the last 40 years?”
After the event, Dr Lin said: “He said he was now 95 and he may previously been infected and now he has immunity, even with new viruses coming the immunity can be stimulated, so that’s possible.
The fact that the Queen’s husband says he feels so well comes as a relief to some royal watchers who have been concerned in recent years that his health was declining following hospital visits.
Back in December 2011, the Duke was treated at Papworth Hospital, near Cambridge, after undergoing heart surgery to have a stent fitted.
He was kept there over Christmas until he was discharged five days later to rejoin the Queen at the Sandringham Estate.
The more recent health scare was in 2012, where he was admitted to the King Edward VII Hospital in London for several days after a bladder infection. This occurred at the time of Her Majesty’s Diamond Jubilee, and as a result, he missed part of the celebrations.
He was released just in time to celebrate his 91st birthday with his family.
Later, Dr Lin, assistant director of the London institute’s worldwide influenza centre, which plays a part with other global centres in determining the content of flu vaccines, tried to explain the Duke’s lack of flu symptoms.