My wife had the bad luck to attend a meeting with an elementary school teacher. 3 days later, she was down with that virus and 2 days later I had it. Down into our lungs it went. We were unable to exercise or do much of anything for a month. We both had asthma, my wife bad enough to get scary. We had our flu shots, too.
We're OK now and back at it, but wow are we crappy. My resting HR was up 15 beats and we lost about 1/3 of our power on the tandem. I figure we'll be back to where we were in about 3 months. We're doing zone 1 or 2 either outside or on our trainers every day and an hour twice a week at the gym.