Detailed text transcripts for TV channel - BBCNEWS - 20210621:22:10:00
Meanwhile planning is under way for a possible autumn booster campaign. but that will depend on the answer to some key questions. first, how long will vaccine protection last? immunity will wane at some point but it is unclear when. antibody levels in trial volunteers, some of whom got their first covid jab over a year ago, will give vital clues. third booster doses might be needed only by certain groups such as the over 65s, as immunity levels often decline faster as people age. second, which booster vaccines will be used? a uk trial is comparing seven different covid vaccines and examining w...