Ahead of the winter months, when cases and transmission are expected to rise again, people will be revaccinated “based on clinical need” in a bid to further raise their immunity levels.
The booster programme is also being implemented to provide protection against new and emerging coronavirus variants, some of which are capable of blunting the effectiveness of the current generation of vaccines.
“Our vaccination programme is bringing back our freedom, but the biggest risk to that progress is the risk posed by a new variant,” health secretary Matt Hancock said.
The additional 60 million doses, which bring Britain’s Pfizer stockpile to 100 million shots, will be used alongside other approved Covid vaccines for the booster programme, the government said.
“We’re working on our plans for booster shots, which are the best way to keep us safe and free while we get this disease under control across the whole world,” Mr Hancock added.
Further details on the autumn programme will be published in due course, the government said.
The final policy is to be informed by advice from the Joint Committee on Vaccination and Immunisation (JCVI) and the results of clinical trials studying whether different vaccine doses can be ‘mixed and matched’.
Known as a heterologous prime-boost, this type of immunisation can only be administered with licensed jabs and, in the context of the UK, would see people inoculated with a third dose which is different to the first two jabs they received.
Due to possible future supply constraints, such an approach may need to be adopted by the UK – but only if the ongoing study, run by scientists at Oxford University, proves to be safe and effective.
Research is also ongoing to establish whether the Covid-19 jabs can be co-administered alongside the flu vaccine, which is rolled out to millions of people each winter.
Overall, the UK has now secured 517 million doses, to be provided by eight different vaccine manufacturers.
The latest data show that a total of 47,540,984 million shots were administered between 8 December and 27 April. Just over a quarter of all adults in Britain have received both doses.
“We are doing everything we can to make sure the most vulnerable are protected from Covid-19 now and in the future,” said vaccines minister Nadhim Zahawi.
Vaccines manufactured by Pfizer, AstraZeneca and Moderna are already in use within the UK, though rolling reviews are underway by Britain’s medicines regulator to assess the Johnson & Johnson and Novavax jabs.
The impact of these vaccines was laid bare in new research published by Public Health England earlier on Wednesday, which showed that a single dose can cut transmission of the virus by up to half.
According to the PHE study, people who became infected with coronavirus three weeks after receiving one dose of the Pfizer or AstraZeneca vaccine were between 38 per cent to 49 per cent less likely to pass it on to household contacts, compared to those who were unvaccinated.
“We know that indoor settings have the highest risk of transmission so these results are really encouraging in terms of the impact of the vaccine on reducing transmission,” said Mr Hancock.
“What it means is the evidence is stacking up that the vaccine protects you, your loved ones and it is the way out of this pandemic.”
Separate research from the Office for National Statistics suggests that more than half of all adults in the UK now have antibodies against Covid-19.
The estimates range from 57.8 per cent of adults in Scotland and 68.3 per cent in England, to 61.0 per cent in Wales and 62.5 per cent in Northern Ireland.
The latest data from the Department of Health and Social Care meanwhile show a total of 2,166 positive tests were recorded in the past 24 hours – down 9.6 per cent from a week ago. A further 29 fatalities were reported, bringing Britain’s death toll from Covid-19 to 127, 480.
Professor Jonathan Van-Tam, deputy chief medical officer for England, said the UK was close to the “bottom level” of coronavirus.
Speaking at a Downing Street press briefing on Wednesday, he said: “We are really in very low levels that are comparable to where we were in September last year.
“We are running as a typical seven-day average at just over 2,000 people testing positive per day.
“My sense is that probably we are at or close to the bottom at the moment in terms of this level of disease in the UK.”
He warned that there are still “some twists and turns ahead,” explaining that the lifting of restrictions on 17 May and then 21 June will place “bad pressures” on the reproduction (R) rate, and acknowledged the continuing risk posed by the coronavirus variants.
However, he said that the success of the UK’s vaccine rollout and the clear impact of the jabs amount to “good pressures on R”.
“I am personally hopeful that if the vaccine programme continues at pace, and continues to be as successful as it’s been, the third wave so to speak, might just be a third upsurge and much less significant, because of the delinking of cases to hospitalisations and deaths.”