Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Pneumonia ?
    ### Response:
    Many germs can cause pneumonia. Examples include different kinds of bacteria, viruses, and, less often, fungi.
                
Most of the time, the body filters germs out of the air that we breathe to protect the lungs from infection. Your immune system, the shape of your nose and throat, your ability to cough, and fine, hair-like structures called cilia (SIL-e-ah) help stop the germs from reaching your lungs.
    