How many diseases are caused by microorganisms?

All diseases by definition are caused by micro-organisms, such as viruses and bacteriae.

For example; Tuberculosis (Bacteria), Aids (Virus), Sars (Virus), Smallpox (Virus), Rabies (Virus), and Yellow Fever (Virus).

Some things that we call diseases are actually afflictions caused by chemicals (such as Miner's Lung), errors in our body processes (Cancer, Hyperactive Thyroid) or contaminations from outside out body (such as gangrene or necrosis of frozen body parts). These would technically not fall under the "disease" category but are conditions.

--The word "Microorganisms" refers to all diseases. The word "disease" refers to an affliction caused by gram-negative bacteria; meaning this, all diseases are results of damage done by gram-negative bacteria, which the word "microorganisms" is a different grouping name for gram-negative bacteria, with "microorganisms" being a larger classification, and gram-negative bacteria being a branch(or type) of microorganism. ~Simple Answer: ALL DISEASES ARE CAUSED BY A MICROORGANISM.