16:06BBC OS2021/01/29 16:06 GMT: Covid vaccine: Single dose vaccine 66% effectiveBBC World Service Duration: 53 minutes Fri 29th Jan 2021, 16:06 on BBC World Service Americas and the CaribbeanBelgian company Janssen says its Covid-19 vaccine is 66% effective Show more GenresNewsFormatsDiscussion & TalkBrandBBC OS Source: BBC Online