Travelers in the eighteenth century often carried certificates proving they had survived smallpox.

十八世紀的旅客常隨身攜帶證明自己曾熬過天花的文件。

Our museum tour guide explained how the smallpox vaccine changed global public health.

我們博物館的導覽員解說了天花疫苗如何改變全球公共衛生。

The pharmaceutical company's annual report highlighted its early research on smallpox treatments.

這家製藥公司的年度報告強調了其早期對天花療法的研究。