More than 700,000 vaccine appointments were booked on the day that jabs became available to people aged 18 to 20 in England.
A total of 721,469 slots were reserved through the national booking service on Friday – the equivalent of 30,000 an hour or more than eight a second.
As the NHS enters the final push to protect the country against COVID-19, everyone aged 18 and over is being urged to make a booking if they are yet to receive a vaccine.
Public Health England says there has been a 79% rise in cases of the Delta variant, first identified in India, in just one week – and the increase in infections has mainly been concentrated in younger age groups.
To cope with demand, an “Olympic effort” to roll out jabs has commenced, with stadiums and football grounds across London transformed into giant vaccination centres.
At the home of West Ham United in east London, 15,000 vaccinations were available yesterday – with “hundreds and hundreds” of people lining up to receive their first dose.
Chelsea’s ground at Stamford Bridge, Tottenham Hotspur FC, Charlton Athletic FC, Selhurst Park and Crystal Palace Athletics Centre were also being used to administer vaccines.
London Mayor Sadiq Khan has stressed that Britons don’t need to be registered with a GP in order to get vaccinated.
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The bookings surge came at the end of a week which had already seen almost 1.8 million appointments made in just three days after the NHS vaccination programme opened up to people in their early 20s.
NHS chief executive Sir Simon Stevens said: “This pandemic has been a challenge for everyone but the various restrictions have hit young people particularly hard.
“That’s why it’s good news that COVID vaccinations are now open to all adults across the country, and already well over three million people in their 20s have now had their first jab.”
Sir Simon added: “The more of us who are vaccinated, the safer we all are, and the sooner freedom can return.”
Health Secretary Matt Hancock added: “It’s incredible to see the enthusiasm young people are showing for vaccination across the country, and it is a testament to the fantastic work of the team in keeping as many people safe from COVID-19 as possible.”
As of 18 June, 73,766,593 jabs have been administered in the UK. Of those, 42,679,268 were first doses and 31,087,325 were second doses.
The Sunday Telegraph has claimed that Mr Hancock failed to tell the prime minister about a major study that showed the effectiveness of vaccines against the Delta variant during a key meeting called to decide whether plans to ease lockdown on 21 June.
According to the newspaper, the health secretary “sat on positive data for three days” – and its report suggests that, if the figures had been disclosed, ministers may have decided to press ahead with lifting restrictions tomorrow.
The Department of Health and Social Care has said the article is incorrect, adding that the information in question “was shared across government before the decision to delay step four was taken”.