Covid: Matt Hancock to lead coronavirus press conference amid fears over vaccine effectiveness

Health Secretary Matt Hancock will lead a coronavirus press conference this evening, with a focus expected to be on Covid-19 vaccines.

A time has not yet been set for the national address but it's likely it will be held at 5pm, as is usually the case.

The health secretary will be joined at Downing Street by Deputy Chief Medical Officer Jonathan Van-Tam and Medical Director of NHS England Nikki Kanani.

It is likely Mr Hancock will provide an update on the effectiveness of the Oxford/AstraZeneca Covid-19 vaccine after a study showed it may not protect against mild illness caused by the South African variant of the virus.

Ministers and scientists have been keen to point out the vaccine is still effective against severe disease caused by the South African strain, but the study has sparked concerns that a top-up third dose of the vaccine may be required in the future.

Some 147 cases of the South African variant have so far been identified in the UK, with experts warning these are likely to be the "tip of the iceberg" due to the fact they are the result of random checks on 5% to 10% of all positive tests.

• Covid vaccine: How many people have been vaccinated in the UK and when will I get it?

• Study shows Oxford/AstraZeneca jab less effective against South African variant

• Fears over South Africa variant raise prospect of autumn booster jab

Next week the government will introduce mandatory quarantine in hotels for arrivals from "red list" countries where variants of concerned have been identified, but critics of the policy are calling for it to apply to everyone travelling to the UK.

It comes as the number of people in the UK who have received a first dose of a vaccine passed the 12 million mark, with jabs administered at a rate of almost 1,000 per minute during a one hour period over the weekend.

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