links:
http://en.wikipedia.org/wiki/Pasteurization
http://en.wikipedia.org/wiki/Small_pox
http://en.wikipedia.org/wiki/Cowpox
http://en.wikipedia.org/wiki/Pasteurization
http://en.wikipedia.org/wiki/Small_pox
http://en.wikipedia.org/wiki/Cowpox
"The Universe is run by the complex interweaving of three elements: energy, matter, and enlightened self-interest." G'Kar-B5