I meant if I have a fever with persistent, unproductive coughing after the flu itself has seemingly subsided. A fever would suggest a lung infection, either causing the bronchitis or vice-versa, but which in any event might require antibiotics lest it degenerate into pneumonia.

I've had pneumonia at least twice as an adolescent, but which went untreated for awhile because it was typical for me to have prolonged coughing and lethargy after a respiratory illness. So while I'll treat my own bronchitis, I have to be mindful that the bronchitis could be secondary, or could have resulted in an infection.