Chris Ryan had been hooked up to oxygen after contracting the virus, which left him struggling to breath and walk.
Once a keen runner, with multiple Great North Runs under his belt, it was a challenge when the physio tasked him with walking a total of ten metres from his bed in the ward he shared with two other patients, to the bathroom and back.
Chris, 55, from Forest Hall, said: “When I got ill, my sense of smell was fine, but I didn’t eat for a week, I was exhausted.
"When my son took me to the Northumbria Specialist Emergency Care Hospital in Cramlington he thought I had cancer because of how bad I looked.
“I was put on oxygen and had quite a high level of support. The team at the hospital were fantastic and really looked after me.
“What gave me focus was regaining my general health. I’d been working from home, and I fell into the trap of working longer hours during the week and doing even more on a weekend.
"I wasn’t running. I was getting out of bed, plonking myself down at a computer and working long hours, not eating properly.
“What I want to help people understand is how important it is just to be healthy. People living good lifestyles and looking after themselves, that’s how we are going to get healthier and build up our immune systems.
“Getting healthier and going from struggling to go to the bathroom and back in hospital to doing the Kielder 10k, having just done the Great North Run, is really exciting for me and I’m just thrilled to be back running.”
Dr Rob Whittle, head of critical care at Northumbria Healthcare, said: “It’s great news to hear that Chris has recovered enough to take on one of the events at Kielder this weekend.
"It is no surprise to me that he is complimentary about the care provided by our hard-working staff at the Northumbria.”