"People have died from phenomena that is not a disease but is an illness"

Per the National Institutes of Health of the United Staes of America, pneumonia most definitely IS a disease. http://www.niaid.nih.gov/topics/pneu...s/default.aspx

Pneumonia is a lung disease. Pneumococcal pneumonia can infect the upper respiratory tract and can spread to the blood, lungs, middle ear, or nervous system.