Earlier quoted context omitted.
Flu are caused by the viruses, pneumonia is the serious bacterial infection of the lungs potentially caused by having influenza. You would count seasonal pneumonia if you wanted to see how serious that seasonal flu was.
Technically no, in addition to bacterial pneumonia (which is often caused by opportunistic infection after a virual invection), there is straight viral pneumonia without any bacterial infection. Even fungi by themselves can cause pneumonia. The difference is that flu does not always cause pneumonia.
Did not think I implied it did. But no, you’re right, it’s why the flu is more dangerous old people.
My understanding of fungus introduced to the lungs is that it’s also carrying bacteria. But yes, there are lots of things you can introduce the lungs cause light to severe pneumonia.
If you want to pro tip, stirring your protein powder well, if you don’t and inhale as powder it on your first sip you can have a bad couple weeks.