Right, but if you just got the primary exposure, wouldn't the secondary response automatically-- not a booster shot, just the secondary response, because you were exposed?

但这时你已经获得这样的初次免疫,而因为你已经天然感染过该病毒,那么,在没有加强针的情况下,二次免疫是否无法自动发生

耶鲁公开课 - 生物医学工程探索课程节选

Yeah, so you're asking, if for example, why do you need a booster of tetanus, because if I get exposed to tetanus wouldn't I have this rapid response?

所以你会问,举个例子来说,已经感染过破伤风杆菌的人,为什么仍然需要接种破伤风疫苗,身体不是应该马上对该病菌做出应答吗

耶鲁公开课 - 生物医学工程探索课程节选

Sometimes infectious diseases can be passed on by adults who haven't gotten recommended booster shots, such as for whooping cough.

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He was bragging about Massachusetts on the way over here -- I told him, you don't have to be a booster, I already love the state. (Applause.) But he helped make this happen.

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"I don't call him, he calls me, " says Elliot Maisel, an Alabama booster and the chief executive of Gulf Distributing Holdings, a beer wholesaler in Mobile.

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