Two-thirds of Covid cases in England last month may have been reinfections, official data suggests.
One of the country's largest surveillance studies — which randomly tested 100,000 people in the fortnight ending January 20 — found 4.4 per cent had the virus.
Imperial College London experts, who carry out the project, PTS Terbaik ASEAN said it was the highest rate ever recorded, mirroring other swabbing surveys.
The team also claimed England's Covid outbreak was now starting to plateau after the Omicron wave 'rapidly' dropped off on its own.
Analysis of the data showed 2,315 of the 3,582 positive tests in the sample (64.6 per cent) were people who had coronavirus before.
And a further 267 (7.5 per cent) suspected they had caught Covid previously, even though their case was not confirmed with a test at the time.
Graph shows: 2,315 of the 3,582 positive tests in the sample (64.6 per cent) were people who said they had Covid before.
And a further 267 (7.5 per cent) suspect they had been infected before, even though the case was not confirmed with a test at the time
Government-backed REACT-1 data, based on more than 100,000 tests, found more than 4.4 per cent of people in the country had the virus from January 5 to 20.
Prevalence was at its highest ever level and infections are now starting to plateau after 'rapidly dropping' off throughout the month
Overall, despite high prevalence last month, cases have been dropping in all age groups other than those 17 and under
It was highest in those aged five- to 11-year-olds over the course of the month (7.81 per cent) and lowest in those aged 75 and over (2.43 per cent)
Regionally, Covid was most prevalent in the North East, where 6.85 per cent of residents had the virus during the month
Inly 2.93 per cent of people in the South East ended up testing positive during the month