is bacterial pneumonia contagious?

Answer 1

Yes it's contagious. Patients in hospitals typically get invaded by Pseudomonas aeruginosa, which is a bacteria. The source of Psudomonas is typically outside the body, so it's contagious.

Merriam-Webster defines contagious as "catching" a "disease". "A disease is the invasion of the body by pathogens." -(quoted from Wikipedia.) Pathogen is defined by Merriam-Webster as "a specific causative agent (as a bacterium or virus) of disease" So I would say both bacteria and viruses are both contagious.

As for Viral Pneumonia NOT being contagious (as answered earlier...) I'm not so sure about that one. I think it is as contagious, if not more so. If you think about it, viruses need to invade healthy cells to reproduce. Therefore they need to be contagious to survive.
Besides, everyone would agree that Chicken Pox (Varicella simplex) is contagious... and that damn thing is a virus. It's caused by the varicella-zoster virus (VZV).

Whereas the source of most bacterial infections already live in your body. If you're talking about respiratory tract, bacterial pneumonia is often caused by poor oral hygiene. The bugs live in your mouth and you end up inhaling them into your alveoli (particularly when your immune system is down, or when you've already been invaded by a viral infection).

If you define contagious as passing from one person to another. It is true. You can cough/sneeze on your hand... handle a door knob and give it to the next person who walks by (when they rub their eyes/nose with their infected hand).

Common resistant bugs include MRSA which is essentially a resistant Staphylococcus aureus, (gram positive bacteria). You hear it in the news all the time. Most recently they made a big stink about MRSA infecting some kid in a high school locker-room. So contagious is the answer.

Answer 2

Yes.Bacteria typically enter the lung when airborne droplets are inhaled, but can also reach the lung through the bloodstream when there is an infection in another part of the body. Many bacteria live in parts of the upper respiratory tract, such as the nose, mouth and sinuses, and can easily be inhaled into the alveoli.

Answer 3

yes it is. it's only viral pneumonia that's not contagious.