The virus is not killed so It's a live virus, which is actually going to infect your intestinal system and reproduce.

病毒没有被杀死,那么它就是活性病毒,也就意味着它将会,侵入你的肠道系统并且会繁殖

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So, you couldn't introduce the live virus in because that would cause the disease not just immunity.

所以 不可以直接接种活体病毒,因为这会使人致病而不仅是引起免疫应答

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So, it's more effective because it's a live virus but it's a little bit more concerning because it's a live virus as well, in that you trust that it's attenuated but could it convert back to a virulent form or a form that caused a disease.

因此,口服疫苗更加有效,因为它是活性病毒,但又是因为这一点,人们也存有更多顾虑,当它处于减毒状态时你会信任它,但是它会不会转变回,强毒壮态或者致病状态呢

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