不知小剂量接触病毒是不是能起到免疫作用，比如隔着口罩接受一点点病毒。

来源: 数与形于 2020-07-05 12:19:10 [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.

Change Ad Consent