Alex is one of the participants in the trial.

He said: “At 77, despite being quite fit and healthy, if I got norovirus and there was nothing there to help me, I would be very worried.”

Fellow attendee Dennis said he wanted to take part as it was a chance to “give back to the NHS”.

Claire Conclan, a ward nurse at the Royal Bournemouth Hospital, said a vaccine would be “amazing”.

She explained: “I’ve been nursing here for 20 years and I’ve seen some catastrophic winters with patients who have been so sick, so it would be an absolute miracle to give them that vaccine.”