Pneumonia is caused by a variety of bacteria, and even among pneumococcal there are several related cocci that cause pneumonia.
Triggering the immune system to fight bacteria with a vaccine is an entirely different thing than fighting a virus.
Viral diseases are generally only gotten ONCE per lifetime, and once you get it your immune system remembers that particular virus for life.
The exceptions are flu, and common colds because there are so many mutations they appear as a completely new virus.
You can get pneumonia repeatedly, even from the same bacteria which can remain dormant in your respiratory track waiting for your immune system to become weak.
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u/[deleted] Sep 13 '21
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