Have you ever wondered why the Black Plague, Ebola and HIV-AIDS don't ever seem to infect some people, I have been wondering about this for some time and lo and behold a documentary appeared on TV over here last night - a pity my TV wasn't working, but after some-one made a comment to me this morning I started searching for evidence for this phenomenon and found it.
http://www.planetpatrol.info/bd.html
http://www.pbs.org/wnet/secrets/previous_s...ague/index.html
Cheers