Boris Johnson has warned that the easing of lockdown restrictions will “inevitably” lead to more infections and deaths as the NHS moved to the next stage of vaccine rollout by inviting people aged between 45 and 50 to book an appointment.

The Prime Minister urged people to continue to “exercise restraint” as beer gardens were packed and shoppers flocked to high streets after the latest round of the Government’s coronavirus restrictions were lifted in England on Monday.

Mr Johnson said that although vaccines had helped, lockdown restrictions had done “the bulk of the work” in reducing Covid-19 infections.

The start of “Phase 2” of the vaccination programme, which involves offering vaccines to healthy adults aged under 50, came after the Government met its target of offering the vaccine to all those in the highest risk groups.

Meanwhile, the Department of Health and Social Care (DHSC) insisted Johnson & Johnson’s decision to delay the rollout of its vaccine in Europe would not derail the UK’s programme to offer a jab to all adults by the end of July.

The UK has 30 million doses of the Johnson & Johnson product on order, but it has yet to be authorised for use by the independent Medicines and Healthcare Products Regulatory Agency (MHRA).

Speaking in Downing Street, Mr Johnson said: “It’s great that we have managed to achieve the target of getting everyone in the one to nine (priority) groups vaccinated by the deadline, by the timetable – a little bit ahead actually, 32 million people now have got their first dose, which is terrific.

Coronavirus graphic
(PA Graphics)

“We are going now to the 45-49 group, they are being asked to come forward.”

But he added: “Of course the vaccination programme has helped, but the bulk of the work in reducing the disease has been done by the lockdown.

“So, as we unlock, the result will inevitably be that we will see more infection, sadly we will see more hospitalisation and deaths.

“People have just got to understand that.”

Vaccine priority graphic
(PA Graphics)

Mr Johnson said there were no plans at present to change the road map out of lockdown. The next “waymarks” on England’s plan to ease restrictions are due on May 17 and June 21.

“But it is very, very important that, if we are to get there in the way that we all want, people continue to be cautious and they continue to exercise restraint and just do the basic things to stop the spread of the virus – washing your hands, giving people plenty of space, doing things in fresh air,” he added.

Mr Johnson urged the eligible people to come forward and get their jab when offered, adding that he remains “very confident” about vaccine supplies despite previous concerns over constraints.

When The NHS’s online booking system opened up to include people over the age of 45 on Tuesday, the website crashed for many.

There are an estimated 3.7 million people in England aged 45 to 49.

The NHS in England said 19 out of 20 of those most at risk of the virus have now received their first dose of a Covid-19 vaccine.

An estimated 27 million people in England are in the top nine priority groups, so it is likely around 25.7 million have received their first Covid-19 jab.

But this suggests around 1.3 million have not had the jab.

(PA Graphics)
(PA Graphics)

One vaccination expert said that it was “vitally important” to vaccinate “the last few per cent”, or they could get infected and end up in hospital.

Professor Jeremy Brown, from University College London Hospitals and a member of the Joint Committee of Vaccination and Immunisation (JCVI), told the Today programme: “The problem here is that 5-10% have not been vaccinated.

“When the virus re-circulates through the community they could get infected and end up in hospital.

“So it’s vitally important that we get that last few per cent.”

Nicola Sturgeon said the people aged over 45 in Scotland would start to get invites “in the next few days”.

In Northern Ireland, people aged over 40 are eligible to get a Covid-19 vaccine, while appointments for 40-49 year-olds began in Wales last week.

Elsewhere:

– People in England have begun to receive the Moderna Covid-19 vaccine.

– The number of registered deaths involving coronavirus in England and Wales has fallen to the lowest level in six months. There were 400 deaths registered in the week ending April 2 where Covid-19 was mentioned on the death certificate – the lowest since October 2, according to the Office for National Statistics(ONS).

-A total of 151,313 deaths have now occurred in the UK where Covid-19 was mentioned on the death certificate, the ONS said.

-The Joint Committee on Vaccination on Immunisation has published its final ‘Phase 2’ advice which is reiterates its interim guidance – that the second phase of the vaccination programme should continue to offer jabs from the oldest to the youngest. The guidance recognises that there are some people that are at higher risk but an age-based rollout is “operationally simple and easy-to-deliver”.

– Surge testing has begun in the boroughs of Lambeth and Wandsworth in south London following the identification of a number of cases of a variant of the virus first found in South Africa.

(PA Graphics)
(PA Graphics)

– Nicola Sturgeon announced that coronavirus travel restrictions in Scotland are to be eased from Friday, and six adults from up to six households will be able to meet up outside.

It comes as it emerged that the US is proposing a “pause” in administering the Johnson & Johnson Covid-19 vaccine to investigate reports of potentially dangerous blood clots.

Johnson & Johnson has since confirmed it will delay rollout of its single-dose vaccine across Europe following the review.

But a DHSC spokesman said: “Our vaccination programme continues to make phenomenal progress, with over 40 million vaccines administered so far.

“We have hit our target to offer a vaccine to everyone in phase one of the vaccination programme and we are on track to offer a jab to all adults by the end of July.”

(PA Graphics)
(PA Graphics)

The 30 million doses are expected to arrive in the second half of 2021 if approved by the MHRA.

The regulator’s director of licensing Dr Siu Ping Lam said: “No vaccine would be authorised for use in the UK unless the expected high standards of safety, quality and effectiveness have been met.

“Vaccine safety is of paramount importance and we will monitor and evaluate any safety reports received promptly and robustly before a decision is made, working and sharing safety data with international regulators as necessary.”

In all, the Government said almost 40 million doses of the Pfizer and AstraZeneca vaccines have been delivered since the rollout began in the UK in December, including 32 million first jabs and more than seven million second doses.

Throughout the current month, the health service has prioritised second doses of the Pfizer and AstraZeneca vaccines with a record 475,230 people receiving their second jab on Saturday.