Ministers need to act “sooner rather than later” if they are to prevent a new surge in coronavirus cases leading to more deaths, a scientist has warned.
Professor Neil Ferguson – whose modelling led the Government to order the lockdown in March – said the UK is facing a “perfect storm” following the easing of controls over the summer.
Ministers are thought to be looking at a temporary two-week “circuit break” in an attempt to break the chain of transmission.
The move could see pubs and restaurants ordered to close or face a 10pm curfew, while socialising between households could be banned.
Prof Ferguson said the Government needs to move swiftly rather than wait until the October half-term break, as some reports have suggested it is considering.
“Right now we are at about the levels of infection we were seeing in this country in late February,” he told the BBC Radio 4 Today programme.
“If we leave it another two to four weeks we will be back at levels we were seeing more like mid-March. That’s clearly going to cause deaths because people will be hospitalised.
“We have in some sense a perfect storm right now of people, as they have been told to, getting back to normal, schools reopening, a surge in cases, so therefore the testing system is under strain.
“So unfortunately we do have to roll the relaxation of measures back a little bit and get contacts down in the population.”
His comments came as new confirmed daily cases of coronavirus hit 4,422 – topping 4,000 for two consecutive days for the first time since early May.
Cases of the virus and hospital admissions for Covid-19 are doubling every seven to eight days in the UK, according to data from the Office for National Statistics.
Meanwhile, Labour has joined the Scottish and Welsh governments in calling on the Prime Minister to summon a meeting of the Government’s Cobra civil contingencies committee – which has not met since May – to consider the worsening situation.
“It has been absolutely shocking to see how monumentally they have failed at the testing, tracing, tracking system that they put in place.”
The Prime Minister remains desperate to avoid another full national lockdown which would hit the economy hard just as activity is beginning to pick up again.
It is just days since the new “rule of six” – banning social gatherings of more than six people – came into force.
The organisation said, as it currently stands, the rule makes it possible for members of six households to meet indoors, potentially several times over the course of one day, with doctors suggesting the number of households is reduced.
It is also urging the Government to reverse its stance on getting workers back to the office by encouraging the public to work from home, in order to reduce contact between people including on public transport.
The Government has also imposed tough new restrictions in large parts of England’s North West, West Yorkshire and the Midlands.
It means by Tuesday, when the measures come into force, around 13.5 million people in the UK will be living under some form of coronavirus controls.
Speaking to reporters during a visit to Oxford on Friday, Mr Johnson said it is clear the long-feared second wave of the pandemic has reached the UK and some additional measures are likely to be necessary.
“We are now seeing a second wave coming in. We are seeing it in France, in Spain, across Europe – it has been absolutely, I’m afraid, inevitable we were going to see it in this country,” he said.
The Government’s Scientific Advisory Group for Emergencies (Sage) said the R number – representing the number of people an infected person will pass the virus to – has risen to between 1.1 and 1.4, meaning cases could rise very quickly.
Last week, the R number was said to be between 1.0 and 1.2.
Overall, an average of 6,000 people in England per day were estimated to be newly infected with Covid-19 between September 4 and 10, almost double the 3,200 people per day from August 30 to September 5.
The figures do not include people staying in hospitals or care homes.