Because to really know, you would have to take two groups of people and give some of them a placebo so they thought they were getting vaccinated, and some of them the vaccine, then challenge them with lethal doses of the anthrax and there would have to be enough lethal doses that all of the placebo, all of the untreated would contract the disease.
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they thought,List([103, 115))
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getting would contract to take challenge to give thought were getting vaccinated
vaccinated
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two groups of people
them with lethal doses of the anthrax T:then
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