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

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