The NHS in England is busier than it has ever been heading into winter, the country’s medical director is warning.
Prof Sir Stephen Powis said rising rates of flu and the vomiting bug norovirus were putting hospitals under huge strain.
Around 95% of beds are already occupied at the start of December – rates normally only seen in the depths of winter.
The warning comes as the prime minister has identified hitting the 18-week target for non-urgent hospital care as one of his six long-term priorities for government.
That prompted senior doctors to accuse the government of avoiding the immediate "crisis" facing the emergency system.
Last week two-thirds of ambulance faced delays when they dropped patients at A&E.
They are meant to be able to handover patients to hospital staff within 15 minutes of arriving, but last week 67% of arrivals took longer than that.
The average handover time was just over 44 minutes.
Dr Tim Cooksley, of the Society for Acute Medicine, said patients needing emergency care were facing "appalling conditions and prolonged waits".
"It's an ongoing crisis which remains far from being resolved effectively.
"The extra cases of winter viruses, such as Covid, flu and RSV, mean many hospitals will fall into critical incidents given the relentless challenges we have faced all year round.
"Despite the positive rhetoric around tackling waiting lists, our concern is that the government continues to avoid acknowledging overtly that there will be no elective recovery without emergency care recovery.
"The two are dependent and need a coherent, co-ordinated approach."
The winter data - the first of the season - also showed the numbers in hospital with flu had reached nearly 1,100, four times higher than at this stage last year.
Nearly 1,400 beds were occupied by Covid patients and 750 by norovirus. Another 142 children were in hospital with RSV each day on average.
This is out of a total of 100,000 beds, but with 95,000 occupied there is very little wriggle room if these numbers continue to climb.
The figures prompted Sir Stephen, the most senior doctor in England, to warn the next few months would be difficult.
“The NHS is busier than it has ever been before heading into winter, with flu and norovirus numbers in hospital rising sharply - and we are still only at the start of December, so we expect pressure to increase and there is a long winter ahead of us.
“For a while there have been warnings of a ‘tripledemic’ of Covid, flu and RSV this winter, but with rising cases of norovirus this could fast become a ‘quad-demic’.”
Rory Deighton, of the NHS Confederation, which represents hospitals, said: “These figures are deeply worrying as they provide yet more evidence the NHS is already under considerable strain before the pressures of winter have peaked.
“We knew that the health service was running hot, with A&Es, ambulances and general practice having their busiest October on record.
"But it is clear that the impact from seasonal viruses is being felt much earlier than in previous years."
Health Secretary Wes Streeting said the problems were not being ignored, saying Labour had inherited a "broken" NHS.
He said the extra funding announced in the Budget and the resolution of strike action by doctors would help relieve the pressure this winter.
And the 10-year plan to be published in the spring would help improve care "all year round".