* 36 A&E units had to send ambulances away temporarily because they were too busy to deal with them;
* 36 hospital trusts reported experiencing 'severe pressures' over the past week.
Officials urged the public to take a "strong dose of common sense" if they felt unwell over the festive period.
Nick Phin, of Public Health England's infection service, said the ill should try to avoid meeting up with relatives.
"You probably won't want to see them and they won't thank you if they go down with flu or norovirus following a visit," he said. Professor Phin urged patients to 'self-isolate' if they had flu or stomach bug symptoms and avoid seeing a GP unless still ill after five days.
Updated advice from NHS England stated: "People should use common sense around whether to see people if they are obviously unwell.
"Be particularly careful around the vulnerable, babies, the elderly, pregnant women and those with chronic illnesses."
Professor Keith Willett, NHS England's acute care chief, urged the sick to stay away from casualty and go to a pharmacist or call 111 instead.
"The NHS is always here to help those who need us," he added. "However, as A&E departments are always exceptionally busy at this time of year, we want to make sure that people know where is the best place to go to receive help.
"We know for example that a high number of hospital admittances can be avoided if people go to their pharmacist for advice at the first sign of illness and so we are encouraging people to use their local pharmacies as well as other services such as NHS 111 and GPs."
Weekly NHS figures released yesterday revealed that hospitals are 94.9 per cent occupied, higher than the 94.5 per cent recorded last year.
This is well above the 85 per cent level considered safe - putting patients more at risk of infections or mistakes by staff.
The 374,268 patients who arrived in A&E in the week leading up to December 18 is a 10 per cent increase on last year. The figures are not comparable however because more hospitals supplied data.
Rates of norovirus are 15 per cent higher than the five-year average and hospitals have had to close 907 beds to contain the spread of the bug.
The crisis in casualty units has been blamed on the shortfall in social care funding provided by councils. Elderly patients cannot be discharged as care has not been set up at home so they languish on wards as 'bed blockers'.
Patients arriving in A&E have to wait on trolleys in corridors until space is found. Separate analysis yesterday showed an estimated 5,000 over-80s will spend Christmas Day in A&E.
Many casualty departments are installing GPs and nurses on their doors to turn away patients who are not judge to be seriously ill.
Taj Hassan of the Royal College of Emergency Medicine said: "Record numbers of patients are being turned away without treatment, elective operations are being cancelled, and bed occupancy is over 95 per cent. This cannot go on.
"Given the difficult situation, we ask the public for their help and patience over the festive season by only attending if it is an emergency."
Nigel Edwards, of the Nuffield Trust health think-tank, said: "These figures illustrate the very real pressures that NHS hospitals are under this winter."
