其目标是，提供一种能抑制所有季节性和流行性流感病毒的疫苗，像接种麻疹疫苗和小儿麻痹症疫苗那样为人们接种流感疫苗。即使不能保证终生免疫，也要保证在几年内为人类提供保护。

The goal is to provide protection for years, if not a whole lifetime, against all seasonal flu strains and pandemic strains, making flu inoculation much more like that for measles and polio.

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2010年的大多数病例都是出现在一些无小儿麻痹症的国家，这些国家由于对于疫苗注射麻痹结果导致病毒从边境传入。

The majority of cases in 2010 were in countries that had been polio-free until the virus travelled back across borders and caused outbreaks in areas where people had gotten lax about vaccination.

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同时，抵抗小儿麻痹症病毒的疫苗的功效没有像天花疫苗那么有效，天花疫苗非常有效，以至于它只需要打一针就可以保护一个人不受侵害。

Also, the vaccines against polio are not as effective as the smallpox vaccine, which was so powerful that a single vaccination protected almost everyone.

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As those doses were given you look at the prevalence of polio within the United States.

随着疫苗的使用,你可以看到全美小儿麻痹症

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In the Sabin vaccine, or the oral polio vaccine, now you have a non-virulent virus.

在沙宾疫苗,即口服小儿麻痹症疫苗中,存在非致病性病毒

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This was of great concern because the number of polio cases shouldn't go up as the vaccine is being even more actively distributed through the country, so what happened?

这个现象让人担心,因为小儿麻痹症的发生数量,不应该在疫苗全国范围内普及后,反而有所上升,那么到底发生了什么

耶鲁公开课 - 生物医学工程探索课程节选