It was easy to tell if somebody had an infectious disease but you might not have known that they had cancer at that time and they just died.

如果有人患有感染性疾病,那很容易判断,但在那个时候医生可能不知道,病人得的就是癌症,病人就这么死去了

耶鲁公开课 - 生物医学工程探索课程节选