It spreads quickly once tiny beads of fluid enter your body, often from a sneeze, cough, or kiss. There are hundreds of viruses that can cause a cold; you can never build up immunity to all of them.

一旦侵入身体一丁点含病毒的液体，病毒就会快速蔓延开来，常常一个喷嚏、一个咳嗽或一个亲吻就足以致病，因为导致感冒的病毒有成百上千种，所以身体无法对所有病毒都产生免疫。

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