MASS vaccination appears to be increasing people’s protection against Covid-19 in the whole of the UK but with “substantial” variations across the nations and regions, the latest data on antibodies suggests.

It comes as Nadhim Zahawi, the UK Government’s Vaccines Minister, said the early data on whether mass vaccination did indeed have a direct effect on reducing Covid transmission was “really encouraging” but stressed more information was needed before any firm decisions could be made on reopening society.

Having antibodies in the blood indicates that people have either previously been infected with the virus or have had a Covid-19 vaccine.

The Office for National Statistics[ONS] said that in England an estimated one in five adults would have tested positive for antibodies against the virus on a blood test in the 28 days up to February 1. This compared to one in seven in Wales and Northern Ireland and an estimated one in nine in Scotland.

While older people were more likely to have antibodies in England, in Scotland, Wales and Northern Ireland the highest rates were seen among younger adults.

The ONS suggested that the increasing number of people with antibodies reflected the effect of the vaccine programme as well as the high levels of infection seen in recent months.

Esther Sutherland, principal statistician for its Covid-19 Infection Survey, said: “Antibody positivity rates have increased across all four nations and the effects of the vaccination programmes have begun to appear, especially in the older age groups.

“In England, those aged 80 and over currently have the highest percentage of antibody positivity, most likely due to the high vaccination rate in this group.

“In Wales and Scotland those aged 16 to 24 years old have the highest percentage and in Northern Ireland it’s in 25 to 34-year-olds.

“We would expect younger groups to have high levels of antibody positivity after the period of high infection rates we have seen in the last few months.

“We will continue to closely monitor antibodies as the UK vaccination programmes continue to be rolled out.”

The ONS pointed out how there was “substantial variation” in antibody positivity between the regions in England.

In London, for example, almost one in four people were estimated to have antibodies, 24.8%, compared to almost one in eight in south west England, 11.6%.

There also appeared to be varying rates of antibody positivity in the elderly across the four nations although the researchers cautioned that the figures only related to those living in private households so would not reflect those in care homes.

The ONS analysis said: "The percentage of people testing positive for antibodies in the oldest age groups varies considerably between nations. This could be explained by the varying approaches to vaccine distribution in different nations." 

In England, there were 40.9% of people aged 80 years and over testing positive for antibodies. In Wales and Scotland, the respective figures were 12.7% and 11.6%.

The data for Northern Ireland includes those over the age of 70 and 9.1% of this group were estimated to have antibodies for the virus.

The data shows that for all age groups over 16 it is estimated that in England, 18.5% of the population have antibodies - 8.3m people, in Wales, the respective numbers are 14.4% and 365,000 people, in Northern Ireland, 13.6% or 201,000 and in Scotland, 11.7% or 521,000.

With pressure building for the beginning of the easing of restrictions to occur across the country, Mr Zahawi continued to adopt a cautious approach, saying: “We’re beginning to see more and more data but at the moment it’s far too early to begin to speculate on the quality of the data.”

Referring to two large-scale studies, he went on: “We’ve got to make sure that you bring down the infection rates, hence why we’re waiting to see the data on transmission. The Oxford team had some early data which is really encouraging on transmission, which has to be peer-reviewed.

“Ultimately, what we want to do is make sure the vaccines are delivering that bridge; you break the link between infection rates and hospitalisation and serious illness and deaths.”

Pointing to a timescale that could run to Easter, the minister noted: “We should be able to see really good data in the next few weeks from those studies.”

On Monday, Boris Johnson said he wanted the current lockdown to be the last one – and for the unlocking to be “irreversible” – ahead of the publication of his “road map” for England on Monday.

The Prime Minister will analyse data this week on coronavirus case numbers, hospital admissions, deaths and the impact of the vaccine rollout as he prepares his plan to reduce restrictions south of the border.

The decision by Nicola Sturgeon to reopen from Monday schools for the youngest children and those secondary school pupils needing to complete assignments will pile pressure on Mr Johnson to follow suit. He has already pointed to the prospect of some schools reopening south of the border from March 8.