BackgroundsThe infectious disease had once been one of the most deathful diseases to human being.

背景传染病曾经是人类的主要健康危害因素，在人类历史上引起过大量人群的死亡。

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BackgroundsThe infectious disease had once been one of the most deathful diseases to human being.

背景传染病曾经是人类的主要健康危害因素，在人类历史上引起过大量人群的死亡。

youdao