About one in seven people in private households in England had contracted coronavirus by mid-January, according to Office for National Statistics (ONS) estimates.
The figure is equivalent to 6.9 million people – 15.3% of the population.
The estimate is up from one in nine people in December, last year, and one in 11 people in November.
The numbers are the proportion of the population who are likely to have tested positive for antibodies to COVID-19, based on blood test results from a sample group aged 16 and over.
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Some 21% of people in London are estimated to have tested positive for antibodies in January.
In Wales, the latest figures show one in nine people had coronavirus in mid-January (up from one in 14 in December), and one in 10 in Scotland (up from one in 13), while the data for Northern Ireland is one in 11 (up from one in 14).
The figures are the proportion of the population who are likely to have tested positive for antibodies to COVID-19, based on blood test results from a sample of people aged 16 and over.
The age group with the highest percentage of antibodies varies across the UK, as does the positivity rate for antibodies across the English regions.
It comes as new research from UK Biobank found that 8.8% of the UK population had been infected by December 2020, rising as high as 12.4% in London and as low as 5.5% in Scotland.
The study found that coronavirus antibodies last for at least six months after infection for the majority of people who have had the virus, with 99% of participants retaining antibodies for three months after being infected, and 88% for the full six months.