The two most common causes of pneumonia are from viral pathogens or bacterial pathogens. Bacteria. The most common type of bacterial pneumonia is called pneumococcal pneumonia.
While all pneumonia is inflammation caused by an infection in your lungs, you may have different symptoms depending on whether the root cause is a virus, bacteria or fungi. Bacterial pneumonia tends to be more common and more severe than viral pneumonia. It’s more likely to require a hospital stay.