The head of NHS England says the NHS 'is running hot,' and urged people to book their Covid booster jabs.
As the government attempts to vaccinate as many people as possible ahead of winter, Amanda Pritchard said the health service has measured a record number of A&E attendances and 999 calls.
Warning the next few months could be difficult, Ms Pritchard appealed to anyone who has not yet had a Covid-19 jab to do so, saying it was an "evergreen" offer.
There have been 141,805 deaths within 28 days of a positive tests reported by the Department of Health and Social Care since the pandemic began in early 2020.
The latest government statistics show that 579,709 people have been admitted to hospital with coronavirus over the course of the crisis, with 1,034 patients in ventilation beds.
"There is no doubt that the NHS is running hot and there are some very real pressures on health and social care," Ms Pritchard said.
Earlier Pritchard said Covid cases were 14 times higher than this time last year. NHS England later clarified she was referring to the most recently published statistics in August.
The NHS chief executive went on to suggest flu and other respiratory conditions can also pose a heightened threat as we head into winter - which will see people socialising indoors more often where viruses can easily spread.
"So, it is going to be really important that people absolutely do take the steps they can to protect themselves," Ms Pritchard added.
The comments come as the NHS renews its drive to increase Covid-19 booster uptake, with people allowed from Monday to book their appointments a month before they are eligible.
On Sunday, the government announced it had administered 10 million booster shots, which are available to people over 50 and those deemed most at risk from the virus.
The NHS, however, says there are still 4.5 million people who haven't had a first dose.
Around 30% of over-80s and 40% of over-50s in England are yet to receive a booster shot of vaccine, the Department of Health and Social Care said.
The latest government figures indicate that 79.7% of people aged 12 and over have had two doses of the coronavirus vaccine.
Health Secretary Sajid Javid has said those eligible for their Covid-19 booster vaccine or third dose should get one to help avoid a return to coronavirus restrictions over Christmas.
He said if “we all come together and play our part” then the country can “avoid a return to restrictions and enjoy Christmas... “We know immunity begins to wane after six months, especially for the elderly and the vulnerable, and booster vaccines will top-up their protection to keep people safe over the winter."
Listen to our coronavirus podcast for the latest analysis
Meanwhile, tens of thousands of care home staff in England have not been fully vaccinated against coronavirus and are set to lose their jobs next week, latest figures suggest. Around 89.4% of staff working in older age care homes had received two vaccine doses as of October 31, according to data from NHS England. The remaining 49,040 staff – around one in 10 of the total – had not been recorded as having received two doses at this point.
The equivalent figure for staff in care homes for under-65s is 13.6% – 11,924 staff.
The government has made it mandatory for staff in registered care homes in England to have both jabs as a condition of deployment, unless they are exempt for valid medical reasons. From Thursday, it will be a legal requirement for staff who are not exempt to be doubly vaccinated if they are to continue in their roles.