So,as the vaccine was passed from arm to arm, it became less potent, and the length of protection that it would give you varied.

所以当疫苗从一个人传给另一个人之后,它的防治效力会减弱,它带给人的免疫期限也会改变

耶鲁公开课 - 生物医学工程探索课程节选

So, if you were someone that was getting it after it had been passed through many people, you wouldn't have as strong or as lengthy a protection as the first individual did.

如果一个疫苗经过很多人的传递,再接种到你身上,你不会获得像第一个接受疫苗的人,那样强效持久的免疫效果

耶鲁公开课 - 生物医学工程探索课程节选

The other problem is that as it was passed from me to another individual, to another individual, then the vaccine could change in some ways that were hard to predict because what accumulates in the lesion in my arm is different in some way than what accumulates in the lesion on a cow.

另外一个问题是当疫苗从我这传到另一人,到另一个个体,疫苗可能会发生某些改变,这种改变很难预测,因为胳膊上积累的病变,与牛身上积累的病变是不太一样的

耶鲁公开课 - 生物医学工程探索课程节选