Cowpox was historically used to develop the smallpox vaccine.

牛痘在历史上被用来开发天花疫苗。

The scientist studied cowpox to understand its effects on humans.

科学家研究牛痘以了解其对人类的影响。

Farmers were once commonly infected with cowpox from their cattle.

农民曾经常常从他们的牛群中感染牛痘。

The doctor explained how cowpox can provide immunity against smallpox.

医生解释了牛痘如何能提供对天花的免疫力。

The outbreak of cowpox in the village caused concern among the residents.

村里牛痘的爆发引起了居民的担忧。

Smallpox and cowpox viruses are from the same family.

天花与牛痘是同源的。

A vaccine prepared from the cowpox virus and inoculated against smallpox.

牛痘苗从牛痘毒素提取的用来预防天花的疫苗。

Cowpox is a skin disease that resembles smallpox and infects cows.

牛痘是一种和天花很像，但感染在牛身上的皮肤病。

In nineteen century, Enligh doctor Pearson came to Macao to spread the cowpox vaccination.

到19世纪时, 英国医师皮尔逊到澳门推广牛痘术.

The discovery of the cowpox vaccination let the danger of vaccination more less, and cost lest.

牛痘术的发明使种痘的危险性更小, 花费也降到最低,故而很快在全世界推广开来.