translation.en: In the last century -- that's the one that was seven years ago -- half a billion people died from smallpox: more than all the wars in history, more than any other infectious disease in the history of the world.
translation.zh: 就在上个世纪--也就是7年前 有5亿人因为感染天花而死 这一数字比历史上所有因为战争死亡的人数还要多 也比任何其他感染性疾病带来的死亡个案更高