Scientists say an experimental vaccine reduced the risk of infection in human beings by thirty-one percent and was safe.

VOA: special.2009.10.13

There's a lot of engineering that we've already talked about in terms of producing quantities of the vaccine, producing it reliably, producing it safe, distributing it, and keeping track requires a level of sophistication that maybe you wouldn't have thought about initially.

我们已经讲过很多工程方面的内容,比如大批量制造疫苗,制造可靠的疫苗,制造安全的疫苗,分派发放疫苗,以及一个完善的随访监测系统,你们最早可能没有想过这些冬夜

耶鲁公开课 - 生物医学工程探索课程节选

Scientists say an experimental vaccine reduced the risk of infection in humans by thirty-one percent and was safe.

VOA: special.2009.09.30

Experts say the vaccine is safe and very effective.

VOA: special.2009.05.26

The vaccine proved safe and a close match with circulating virus.

VOA: standard.2010.01.18