You have to inject it multiple times because the first blip that you get in immune response is not very high, you have to boost and often you have to boost again in order to get a high enough response to be protected.

你必须得进行多次注射,因为第一次注射,无法使免疫系统产生强烈反应,你得要增强免疫,通常还得再增强一次,以使反应足够强烈,从而起到保护作用

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It's the one where you have to get three shots over a period of six months, and so you have to remember to go back, you get a first ba--you get a first shot, you have to remember to go back after a month and get a second shot, you have to go back after six months and get a third shot.

这种疫苗需要在六个月里注射三次,所以你要记得再去,你第一次,你第一次注射后,你要记得一个月后再去注射第二次,六个月后,你还得再去注射第三次

耶鲁公开课 - 生物医学工程探索课程节选