Check this out, if you didn't already know about whale.to
http:// whale.to/a/smallpox_hoax.html
The sources are from millennia ago, when's the last time a doctor did this
"Dr Rodermund, a physician in the state of Wisconscin, created a sensation by smearing his body with the exudate of smallpox sores in order to demonstrate to his medical colleagues that a healthy body could not be infected with the disease. He was arrested and quarantined in jail, but not before he had come into contact with many people. Not a single case of smallpox developed through this "exposure"....I have ...handled intimately thousands of cases of contagious diseases, and I do not remember a single instance where any of us was the least affected by such contact."---Henry Lindlahr MD (Philosophy of Natural Therapeutics p 39)