Comment by TeMPOraL

"Common cold" is what we call flu/COVID/bunch of other stuff when symptoms aren't severe enough to bother checking. There is no "cold virus", as cold isn't a specific sickness but a destination; it's a catch-all for respiratory pathogens that evolve their potency away.

By the time someone is able to tell they have "the flu", they should've been on a sick leave for 2-3 days already.