Flu levels are soaring with one in five cases in hospital suffering from the deadly strain dubbed "Aussie flu", official figures show.

The statistics from Public Health England (PHE) show that across the country, rates of flu have close to doubled in one week, with a 51 per cent rise in cases hospitalised.

The reports show almost 2,000 patients hospitalised with confirmed flu so far this season - with more than a fifth infected with the deadly strain A(H3N2) - dubbed “Aussie flu” after it fuelled the country’s worst flu season for two decades.

The total death toll is now 85, up from 48 in previous reports this season.

Health officials have urged NHS staff to take up flu vaccinations, with the country's chief medical officer today backing calls to make it mandatory for frontline staff to have the jabs.

Prof Dame Sally Davies pleaded with doctors and nurses to have the jab for the sake of their patients, with less than one third of healthcare staff vaccinated in some hospitals.

“Healthcare workers owe a duty to protect their patients – go and get vaccinated,” she said.

Pensioners, adults with chronic health problems like diabetes and asthma, pregnant women and children under the age of nine are all eligible for free NHS vaccination.