Hamilton, Gary. Dead Man Walking. New Scientist 2303:30-33, 11 Aug 2001
As an example of microorganisms causing disease (or perhaps not!) check out an interesting article on H. Pylori and ulcers. As usual, the situation is more complex than modern medicine is easily able to deal with, although the bottom line here appears to be that H. Pylori is bad, even though it may have some good effects.
The human ecosystem needs to be investigated as a rainforest of microorganisms with complex ecological balances. The epidemiology of the internal human system is a new science that needs to be launched, funded, and studied to answer many of the open questions of the day. What really causes heart disease? Why do statin drugs decrease the risk of some heart disease while increasing ther risk of other types of heart disease? Why can’t we prevent or cure cancer? If we had a cure, cancer survival rates would be going up dramatically and they are definitely not as shown in a previous posting. Why is medical error the third leading cause of death after heart disease and cancer? And on and on. The list of unanswered questions is endless.