Flu hospitalisations are ten times higher than this time of year two years ago as Britain is braced for its worst flu season on record.

A new flu strain is causing more severe illness even in otherwise healthy people and doctors had warned H3N2 “can kill” because it has mutated to be particularly aggressive. The number of people in hospital in England with flu is more than 50% higher than the figure at this point in 2024, according to the first of this year's NHS winter “situation reports”.

An average of 1,717 flu patients were in beds in England each day last week, including 69 in critical care. This is the highest on record for the time of year.

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This is up 56% on the same week in 2024, when the total was 1,098 with 39 in critical care. But it is ten times higher than at this point in 2023, when there were an average of 243 flu patients, and in 2022, when the average was 772.

Professor Julian Redhead, NHS England's Medical Director for Urgent and Emergency Care, said: “Today’s numbers confirm our deepest concerns: the health service is bracing for an unprecedented flu wave this winter. Cases are incredibly high for this time of year and there is no peak in sight yet.

“The NHS has prepared earlier for winter than ever before, but despite that we know that ballooning flu cases coinciding with strikes may stretch our staff close to breaking point in the coming weeks.

“As always, use A&E & 999 for life threatening conditions and serious injuries, and with just a couple of weeks left to ensure maximum immunity from flu for Christmas day, I urge anyone eligible to come forward to get their jab."

The figures have been published by the NHS as part of its first weekly snapshot of the performance of hospitals in England this winter.

It comes amid warnings more NHS patients will spend Christmas away from their families on a busy hospital ward because doctors are on strike.

The British Medical Association called another five-day strike from 7am from December, in the week before Christmas when hospitals are busy trying to discharge patients where possible.

Health Secretary Wes Streeting said: “Winter is a hard time for the NHS, but because we acted earlier than ever we’re seeing progress - with faster ambulance response and handover times compared to this time last year.

"This progress is being put in real jeopardy by the BMA's leadership, whose reckless behaviour to time industrial action at the height of winter, will put more patients are risk and bear down hard on their NHS colleagues in the run up to Christmas.

"We will do all we can to weather this storm. I am determined that with the proper planning, record investment and modernisation this government is bringing in, we'll have a more resilient NHS for this winter and beyond."

UK Health Security Agency (UKHSA) estimates show that deaths from flu in England stood at 7,757 last winter compared to 3,555 the year before. Child deaths involving flu also increased from 34 to 53.

It comes after the head of the NHS warned Britain could face its worst flu season on record this winter. Data from Australia - which is six months ahead of the UK with its flu season - shows infections reached the highest levels since records began in 2001 while schools have closed in Japan due to a flu epidemic.

Australia and Japan have both been hit hard by flu because the main new strain, called H3N2, has mutated to better escape immunity from previous vaccines. This is because it has mutated to be particularly aggressive. Jabs still offer significant protection - and often prevent serious illness - but less so than previous years.

NHS England said it has already delivered almost 17m flu jabs this year - 350,000 more than this time last year.

Parents are being reminded to complete their child’s vaccination consent forms to schools, or to book an appointment for 2 to 3-year-olds, to ensure their child gets protected against flu ahead of the Christmas holidays.

Prof Redhead added: “There have never been more ways for people can get the care they need, so for non-life-threatening care, people should call NHS 111 or use 111 online, which can direct you to the most appropriate place."

As well as for higher pay, the BMA strike action is in protest at training "bottle necks" which can leave doctors unemployed because of a lack of training places.

BMA resident doctors committee chair Dr Jack Fletcher said: “What’s truly reckless is not the timing of this strike, but the Government’s refusal to fix the crisis staring them in the face. And what’s genuinely cruel is shutting the door on thousands of doctors who are desperate to serve the NHS and relieve those same winter pressures.

"At a time when waiting lists are at record highs, thousands more doctors could be on the front line, giving care, becoming our consultants of the future. That should outrage every member of the public. Patients deserve better. Doctors deserve better.

“The public want an NHS that actually works. This crisis may not have been originally created by this Government, but without a real plan they are on the verge of owning every inch of it.”