Hospitals in Britain are facing a "worst case scenario" from a wave of super flu as flu hospitalisations jumped 55 percent in a week.
NHS England said that an average of 2,660 patients per day were in a hospital bed with flu last week, the highest ever level for this time of year, up more than half in a week, in what it described as an "unprecedented wave of super flu".
There are enough flu patients each day to fill more than three whole hospital trusts, it added.
"The number of patients in hospital with flu is extremely high for this time of year," Professor Meghana Pandit, NHS National Medical Director, said in a statement.
"Even worse, it continues to rise and the peak is not in sight yet, so the NHS faces an extremely challenging few weeks ahead."
The NHS is urging people to get their flu vaccination to help prevent them getting seriously ill.
More than 17.4 million have been vaccinated so far this year - over 170,000 more than this time last year.
Health leaders have told people who feel ill to wear face masks when using public transport, while some hospitals are requiring masks be worn.
Health secretary Wes Streeting said, “There is a tidal wave of flu tearing through our hospitals."
A planned five-day strike by resident doctors - qualified physicians who make up nearly half of the medical workforce - is due to start on December 17, adding more pressure to an already stretched healthcare service.
To try to stop the strike, Streeting presented the union with a new package of working conditions on Wednesday, which they are currently considering.
He said, “The offer I have made to the BMA would help solve the jobs problem resident doctors are facing, and bring an end to strike action this Christmas, which is the most dangerous time of year.
"I urge resident doctors not to inflict further damage on the NHS, vote for this deal, and call off the Christmas strikes.”
