Covid: Boris Johnson leads coronavirus press conference following 'encouraging' vaccine study

Boris Johnson is leading a coronavirus press conference Wednesday evening, with a focus expected to be on "encouraging" results from a vaccine study which showed the Oxford jab may reduce transmission of Covid by 67%.

The prime minister is joined at the press conference by Chief Medical Officer Chris Whitty.

An update will be provided on the study, looking at the Oxford/AstraZeneca vaccine, which showed single dose of the jab may reduce transmission of coronavirus by two thirds.

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The finding serves as a major boost to the UK’s policy of delaying the second jab for up to 12 weeks.

Before these results, little was known about how effective the Covid-19 vaccines were at preventing transmission of the disease.

Mr Johnson said data from the study was “really encouraging”.

On Twitter, he said the "new study today shows the Oxford/AZ vaccine provides significant protection against the virus".

"I’m incredibly grateful to all our scientists, NHS staff and volunteers working on our vaccination programme."

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