I think the smallpox vaccine we made now would probably be better, more effective, and safer than the vaccines we made in the '50s.

我相信若我们现在制造天花疫苗,应该会比五十年代的更有效更安全

耶鲁公开课 - 生物医学工程探索课程节选

And so they're already very safe, very effective vaccines available for many infectious diseases.

所以这些疫苗非常安全有效,常备用来对付各种传染病

耶鲁公开课 - 生物医学工程探索课程节选

Then, they did preliminary studies of safety and effectiveness in people.

接着,研究人员对疫苗在人体中的,安全性和有效性进行初步研究

耶鲁公开课 - 生物医学工程探索课程节选