Think for a minute about what happens if you get infected with a virus.

想一想,如果你被病毒感染了会怎么样

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So if you got infected with smallpox, you got the disease.

如果你感染了天花病毒,就会得这种病

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Now, normally that's a good thing because if you're out in the world and you get infected with adenoviruses you recover from it, your immune system can get rid of it.

通常情况下这是好事,这可以让暴露在户外的你,免于腺病毒的侵害,你的免疫系统可以清除病毒

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So, if you look in the blood of patients that are infected with Hepatitis B you find a lot of Hepatitis B surface subunits, proteins without the nucleic acid circulating in their blood.

因此,如果你观察一下,已经感染乙肝病毒患者的血液,你会发现许多乙肝病毒的表面亚基,以及血液循环中存在没有核酸的蛋白质

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There weren't people that got infected, like you can get infected with hepatitis B or tuberculosis, and not even know you're infected.

这不像人们感染了,像B型肝炎或者肺结核这类病时,都有可能不知道自己被感染了

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