Three-quarters of healthcare staff in Portsmouth Hospitals Trust are not vaccinated against flu this year as cases in the trust rise, new figures show.

The NHS has urged people to take up the jab as hospitals are facing a "flood of flu cases".

Figures from the UK Health Security Agency show 27% of frontline healthcare workers in Portsmouth Hospitals NHS Trust had been vaccinated against flu as of the end of November, meaning 73% were not protected.

Across England, 68% of frontline healthcare workers have not been vaccinated for influenza so far this winter – a jump from 62% last year.

It comes as the national number of patients with flu in hospital beds jumped 41% in a week and continues to be more than four times the number at this point last year, with an average of 2,629 flu patients in beds last week.

In Portsmouth Hospitals NHS Trust, there was an average of three patients with flu in the week to December 15 – although none were in critical care.

It was a slight increase on two patients the week prior.

Professor Sir Stephen Powis, NHS national medical director, said: "The NHS has been hit hard with an early festive flu season, putting increased pressure on staff as they prepare for the long winter ahead of us.

He added the NHS has been making it "as easy as possible" for people to get the jab, with vaccination centres in supermarket car parks and football clubs.

He warned: "As children finish school and friends and families congregate over the Christmas period we expect viruses to continue to spread so if you haven’t got your flu jab and are eligible please come forward, and the public should think twice about seeing loved ones if they are seriously unwell."

Tim Gardner, assistant director of policy at think tank The Health Foundation, said the current winter crisis reflects a "lack of resilience" in the NHS after a decade of austerity.

Patricia Marquis, the Royal College of Nursing’s executive director for England, added: "As people prepare for the festivities, nursing staff are battling to hold the service together and are deeply concerned about what the coming weeks will deliver.

"Right across the NHS beds are full, A&E is facing increasing pressures, while the growing number of flu cases threatens to overwhelm an NHS and workforce already in crisis.

"Once again winter is exposing the true impact of failures to invest in our nursing workforce. As we head toward 2025, the Government must show it values the profession through action and not warm words."