Head of the International Red Cross Federation's Influenza team, Robert Kaufman, says the impact of a novel virus on a community without immunity is not just about the number of illnesses and deaths.

VOA: standard.2009.09.04

And he was right; they got immunity and were protected from smallpox when it affected their community.

他是对的,当天花在周围流行时,他们具备了对天花的免疫力

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