He realized that this "teach-in" method would be a useful way for the public to express concern about the environment to federal and state officials.

VOA: special.2010.04.21

We did not yet have good methods for screening blood to look for HIV, we didn't have the ELISA technique that I--we talked about in section a few weeks ago and so there was a great concern that there might be other diseases that you'd be passing on from-- unknowingly from this subset of patients that you're isolating the vaccine from.

那时我们还没有一种好的方式,来从血液中筛查出HIV,也还没有ELISA技术,该技术我们在几周前的一个章节中谈到过,因此,那时仍存有,很大的担心,那就是你有可能,在不知情的情况下,被那些病人,感染上其它疾病,因为疫苗就是从他们身上提取出来的

耶鲁公开课 - 生物医学工程探索课程节选