More than one in two people (54.7 per cent) in England had coronavirus antibodies as of March 14, a new study by the UK’s Office for National Statistics found.
Data suggested a clear pattern between vaccination and testing positive for Covid antibodies, the ONS said, more good news after England lifted some lockdown restrictions on Monday.
The results showed similar levels of protection existed across much of the UK, with half of Wales (50.5 per cent) and Northern Ireland (49.3 per cent) having some immunity against the virus.
The outlier was Scotland, where the level of protection dropped to two in five people, or 42.6 per cent of the population.
The presence of antibodies in the blood indicates that someone has either had the virus or been immunised.
The ONS was able to adduce a link between the vaccine and Covid-19 antibodies by including modelled estimates of the number of people who have received at least one dose of a vaccine, across all four countries of the UK.
The data showed a reduction in antibody positivity rates among older people during the most recent days in the period analysed.
This was probably down to prioritised age groups having received their first vaccine dose but not their second, the ONS said.
As of March 28, a total of 30,444,829 people had received their first dose of a Covid vaccine, while 3,674,266 had received their second.
This equates to more than half the population, so this newly confirmed relationship between vaccination and immunity augurs well.
However, ONS data on Monday showed vaccination rates were lower in ethnic minority groups and that fewer Muslims in England were vaccinated than any other religious group between December 8, 2020 and March 11, 2021.
In a bid to address reluctance in the black British community, veteran comedian Lenny Henry on Tuesday wrote an open letter encouraging take-up,
ONS data also showed that those in the most deprived areas of England were less likely to be vaccinated than those in the least deprived.
Vaccine hesitancy seemed to be evident in Wales too, where more than a quarter of people across Swansea Bay on Monday didn't attend their scheduled inoculation appointment.
"Out of 1,750 appointments, 492 were classed as DNA (did not attend)," the Swansea Bay University Health Board said.
"We urge everyone invited to attend their appointment. If you can’t make it or don’t want the vaccine, please let us know."
If vaccination no-shows continue to increase as the campaign works its way down through the age groups, there are fears early progress could stall with younger people believing they are safe from the virus without being inoculated.