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       Tube riders enter Notting Hill Gate station, in London, on July 13. The government will end England's pandemic-era social restrictions, such as rules on mask-wearing, distancing and venue capacity, on July 19, even though it is experiencing a wave of new COVID-19 infections.

       Dan Kitwood/Getty Images

       The number of daily COVID-19 infections in Britain has topped 50,000 for the first time since the peak of the pandemic in January, raising concerns about the government’s plans to ease all remaining restrictions in England on Monday.

       On Friday, the government reported 51,870 new cases of the disease, close to the highest daily totals reported last January, when the country was in a near total lockdown. The peak came on Jan. 8 when there were 68,053 new cases.

       Hospitalizations have not risen as quickly as last winter, but the total reached 717 on Friday, up 43 per cent from the previous week; there were also 49 deaths. In January, daily admissions were above 3,000 and some days saw 1,000 deaths recorded.

       The government remains on course to ease virtually all remaining pandemic restrictions across England on July 19. That means nightclubs can reopen, pubs will no longer be restricted to table service and limits on public gatherings will be lifted. Face masks will also no longer be mandatory in most places, although London and some other cities will require face coverings on public transport. Scotland, Wales and Northern Ireland, which manage their own health care services, are also easing most restrictions.

       Prime Minister Boris Johnson has urged people to be careful once the measures are removed. “It is absolutely vital that we proceed now with caution,” he said earlier this week. “And I cannot say this powerfully or emphatically enough. This pandemic is not over. This disease continues to carry risks for you and your family.”

       Health Secretary Sajid Javid has warned that daily case numbers could reach 100,000 this summer before the current surge of infections peaks. He has also insisted that if the government waited to lift the restrictions, it would only delay the coming wave until autumn, when the health service will be coping with flu and other seasonal illnesses.

       The government is banking on the country’s mass vaccination program to keep hospital numbers down so that the National Health Service doesn’t become overwhelmed. Slightly more than two-thirds of adults have been fully vaccinated so far and the NHS is trying to ramp up immunizations.

       However, health care officials say vaccines have weakened but not broken the link between cases and hospital admissions. They note that the rate of hospitalizations has been doubling every three weeks due entirely to the highly transmissible Delta variant, which now accounts for 98 per cent of all COVID-19 cases in the U.K.

       “I don’t think we should underestimate the fact that we could get into trouble again surprisingly fast,” Chris Whitty, England’s Chief Medical Officer, told a science conference on Thursday. “I think saying the numbers in hospital are low now, that does not mean the numbers will be low in hospital in five, six, seven, eight weeks’ time. They could actually be really quite serious.”

       A separate, more detailed survey of infections released Friday by the Office for National Statistics found that the disease was spreading across nearly all of the U.K. The weekly survey showed that as of July 10, one out of every 95 people in England has the virus. That was up from one in 160 in the previous week’s survey. In Scotland one in every 90 was infected, compared with one in 290 in Northern Ireland and one in 360 in Wales.

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       “We are doubling cases every 12 to 18 days,” said James Naismith, a professor of structural biology at the University of Oxford. “This is the last ONS update we will get before the [end] of restrictions on Monday. It is a reasonable assumption that the wave has continued to grow this week and will accelerate after Monday.”

       Julian Tang, a virologist at the University of Leicester, said this week that “even though there will be fewer hospitalizations and deaths, the health care burden across both community and hospitals will increase from COVID-19.” He added that “to this, we may have to include flu and other winter respiratory viruses, if they appear again once all restrictions are lifted – along with the usual winter exacerbations of chronic diseases – and all of this on top of the backlog of other non-COVID diseases that the NHS is catching up with now.”

       More than 1,200 scientists and health care experts have signed a letter to the Lancet medical journal calling on the government to abandon its plans to lift restrictions. “We believe the government is embarking on a dangerous and unethical experiment, and we call on it to pause plans to abandon mitigations on July 19,” the letter said. “Instead, the government should delay complete reopening until everyone, including adolescents, have been offered vaccination and uptake is high.”

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