疫苗效力生疑 英衛生大臣：很擔心南非變種病毒

<img src="https://static.rti.org.tw/assets/thumbnails/2020/08/03/ecaad257e75fde6a85a2ab3717c93731.jpg" width="360" alt="英國衛生大臣韓考克(Matt Hancock) (AFP)"...