What Is Walking Pneumonia

“Walking pneumonia" sounds like it could be the name of a sci-fi horror flick. But it's actually the least scary kind of pneumonia. It can be milder than the other types, and you usually don’t have to stay in the hospital. You could have walking pneumonia and not even know it.

It Might Feel Like a Cold
Walking pneumonia is how some people describe a mild case of pneumonia. Your doctor might call it “atypical pneumonia” because it’s not like more serious cases.
https://www.webmd.com/lung/walking-pneumonia