THE number of people testing positive for Covid is at the highest level in more than a month.
A further 53,945 cases have been reported today as Brits brace for more Omicron infections.
Health chiefs have also recorded 141 more deaths in the past 24 hours as the country heads into the dark winter months.
The last time cases were over 50,000 was on October 21, when there were 51,484.
Case numbers are also up by almost 15 per cent on this time last week, when 47,240 new infections were recorded.
Scientists are already estimating that one in every 300 new cases are caused by the mutant super-strain Omicron, which emerged just last month in South Africa.
There have been 32 confirmed cases of the new variant so far – with 22 in England and 10 in Scotland.
But experts say the true number is likely to be significantly higher.
Medics fear vaccines will be less effective against the strain, sparking a race to offer booster jabs to all Brit adults by the end of January.
And restrictions have been tightened, with masks back in shops and on public transport.
Meanwhile, all travellers to the UK must now quarantine at home until they get the results of a day 2 PCR test.
The new rules fall short of “Plan B” - which includes vaccine passports and working from home guidance.
But Government scientists warn more may yet be needed.
Sage experts say "very stringent" measures may be taken to tackle the variant in the future.
The organisation warned on Monday that the mutation's impact is "highly uncertain" but it could rapidly evolve.
Leaked minutes seen by the BBC say: "The situation could develop quickly over the coming weeks and decision makers may need to act while there is a high level of uncertainty, including the potential need for stringent response measures.
"Any significant reduction in protection against infection could still result in a very large wave of infections.
“This would in turn lead to a potentially high number of hospitalisations even with protection against severe disease being less affected.”
It will be at least three weeks before the picture becomes clearer, at which point ministers are set to review current restrictions.
In brighter news, a brand new Covid drug that cuts the risk of death by nearly 80 per cent has been approved in the UK.
Xevudy (Sotrovimab) was given the green light as it's been deemed safe and effective at reducing the risk of hospitalisation and death in virus patients.
And Britain has secured an extra 114million doses of coronavirus jabs, with fresh deals for both Pfizer and Moderna shots announced.
It raises the possibility of a fourth jab after it was announced this week that every adult will be able to get a booster by the end of January.