I have been curious. Back in December 2019, myself, my dad, my boss and some other friends and family all got sick. It lasted about 3-4 weeks. It was a weird cold. None of us really got that sick, but we all felt terrible, weak and lethargic, aches and pains, slightly feverish some days then not other days, a really bad sore throat to the point where swallowing hurt and not really a cough, but badly congested lungs. Breathing was hard and it was hard to clear the congestion.
It was the length of time that was the most strange and all of us were sick for pretty much the same length of time.
It wasn't the flu, if i get sick that long with the flu, I get fucked up, and colds never last that long for me. This was just like a month of general shittyness. Even then it took probably until around the end of January before I felt 'normal.' again.
We've all sort of speculated half seriously that maybe we had covid, but never really took it seriously.