Hospitals are looking after their highest level of Covid-19 patients for more than seven months.
There were 8,693 people in hospitals with coronavirus on Monday, the most since March 9.
Figures show this was an increase of 11% on the previous week.
Daily cases topped 50,000 for the first time since lockdown ended in one day last week.
It piled the pressure on the government to introduce stricter curbs on freedoms.
Yet the number of patients in hospital are well below those seen at the peak of last winter’s second wave.
At the high point of the pandemic, on January 18, hospitals had four times the current level of Covid patients (39,254 people).
Patient numbers have been on a slow upwards trend since the third wave of the virus began at the end of May.
The figure had dipped as low as 872 on May 27.
Professor Sir Andrew Pollard, who helped create the Oxford/AstraZeneca vaccine, warned the NHS was ‘incredibly fragile’.
But he added: ‘That fragility is only contributed a small amount by Covid and so vaccinating is not going to suddenly make the NHS not be on its knees, where it is at the moment.’
He said hospital admissions now were ‘quite a different story from last year’, with the vast majority of patients having shorter hospital stays and much milder disease.
Many of these people also have underlying health conditions ‘which are destabilised by having a relatively mild Covid infection’, he said.
The government has said high uptake of booster jabs is needed to avoid further restrictions this winter.
Around 22 million Brits will be ready to receive their third jab by the end of January.
But modelling by the London School of Hygiene and Tropical Medicine has suggested infections will peak soon before nosediving over winter, even without ‘Plan B’ restrictions.
Get in touch with our news team by emailing us at [email protected]
For more stories like this, check our news page.