Speaking at a Downing Street press conference, Professor Wei Shen Lim, chairman of the Joint Committee on Vaccination and Immunisation, explained that vaccine recipients should not expect to have immunity until day 22.

He was speaking alongside Dr June Raine, the CEO of the MHRA, and Professor Sir Munir Pirmohamed, the Chairman of the CHM's Expert Working Group, following the approval of the Oxford University and AstraZeneca vaccine.

He added that the first dose is 70 per cent effective between day 22 and the second dose.

Vaccine recipients should get a second dose of the vaccine four-12 weeks later.

Read more about the vaccine: https://www.telegraph.co.uk/global-health/science-and-disease/coronavirus-news-tier-4-announcement-covid-restrictions-oxford/

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