CATCHING both flu and Covid together more than doubles the risk of death, research reveals.
Brits are now being urged to get their influenza jab, with a record 30 million on offer.
It comes as early Public Health England research shows picking up the winter bug at the same time as Covid spells bad news.
Patients with both illnesses were found to be 2.27 times more likely to die than those with coronavirus alone.
And they were also at greater risk of turning up in intensive care.
Health bosses have now launched the biggest ever flu jab drive in a bid to save lives and protect the NHS.
On an average year, 11,000 people are killed by the winter bug and more than 30,000 hospitalised.
Yvonne Doyle, medical director at Public Health England, warned: “If you get both, you are in some serious trouble.
“The people who are most likely to get both of these infections are the people who least likely can afford it.
“It is dangerous to dismiss influenza as ‘just’ the flu – it can be extremely serious and can lead to hospitalisation, permanent disability or even death.
“The flu vaccine is more important than ever, to help reduce transmission of flu and protect the nation from the double threat of flu and Covid.”
More than 19,000 people were tested for flu and Covid as part of the study.
In the 58 cases where experts found patients had both bugs, mortality was 43 per cent.
On the positive side, researchers discovered flu victims were 68 per cent less likely to catch Covid than the general population.
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Experts think both viruses compete to infect the same part of the body and so push each other out.
Another theory is the immune system becomes primed against all bugs once a person falls ill and is better at fighting off new ones.
Deputy Chief Medical Officer Professor Jonathan Van-Tam, said: “There is now some emerging evidence, which clearly suggests that infection at the same time with influenza and with Covid produces bad outcomes.
“The vaccine is the best way to protect yourself from becoming ill with the flu, especially if you are in a vulnerable group.”