You would first get exposed in children-- in childhood and then at a point when you're susceptible to the disease.

在儿童期这个较容易受病毒感染时期,第一次接触该病毒,就会引起发病

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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

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