The Oxford-AstraZeneca vaccine could lead to a "substantial" fall in the spread of the virus, say scientists. The impact of Covid vaccines on transmission has been a crucial unknown that will dramatically shape the future of the pandemic. The study, which has not been formally published, also showed the vaccine remained effective while people waited for a second dose. It was 76% effective during the three months after the first shot...................................This study - on 17,000 people in the UK, South Africa and Brazil - showed protection remained at 76% during the three months after the first dose. This rose to 82% after people were given the second dose.. ......................................The report does not tackle the impact of the new variants on how well the vaccines work.
bbc.co.uk/news/health-55910964
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