Most of Us Should Be Covered...

Interesting: Old Smallpox Vaccination Probably Still Protective

More than 90% of people who received the smallpox vaccine 25 to 75 years ago show substantial immunity against vaccinia, the virus used in the vaccine, according to a report published in the August 17th online issue of Nature Medicine.

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Even decades after vaccination, most people showed significant immunity against vaccinia. If these levels of immunity are at least partially protective, then the illness and death rates as a result of an intentional smallpox outbreak would be 'substantially reduced,' the researchers state.