The Human Microbiome: A True Story about You and Trillions of Your Closest (Microscopic) Friends

... of historic agents of change, while modern day infectious diseases include malaria, tuberculosis, cholera and HIV/AIDS, to name a few. The scientific study of microbiology, which led to important discoveries such as Louis Pasteur's "germ theory of ...

http://www.actionbioscience.org/genomics/the_human_microbiome.html