http://www.lungusa.org/site/apps/nlnet/content3.aspx?c=dvLUK9O0E&b=2060321&content_id=%7B08C669B0-E845-4C9C-8B1E-285348BC83BD%7D¬oc=1
This fact sheet provides statistical information on the prevalence of pneumonia in the United States, and discusses the differences between viral and bacterial pneumonia. Vaccination for high risk groups is recommended.