I was incredibly strong and fit,” says Lucy Keighley. And she looks it, in the photo she is showing me, taken a few years ago. She is with her best friend, Lorna; they have just completed a 15-mile race on the North York Moors. “It was a brutal race,” she says. “But it was great. I was happy.” Today, although it’s quite dark in the room (she doesn’t get on well with bright light), I can see a tear rolling down her cheek. “I don’t know if I’m ever going to get back there.”

In the most recent findings by the Office for National Statistics, released in April, an estimated 2 million people in England and Scotland (3.3% of the population) self-reported experiencing long Covid, meaning symptoms that continued for more than four weeks after infection, although many reported their symptoms had lasted two years or longer. Of those, about 1.5 million felt their day-to-day activities were affected, while 381,000 said their day-to‑day activities were “limited a lot”. Worldwide, at least 65 million people are estimated to have long Covid.