Health chiefs are urging Britons to get jabbed as soon as possible amid warnings up to 60,000 people could die from flu this winter.
Experts fear a massive surge in cases because social distancing measures kept infections low last year, reducing population immunity.
The Government has launched the biggest flu programme in the history of the NHS, with more than 35 million people in England eligible for a free vaccine.
Covid booster jabs are also being rolled out, with around 1.7 million people given these third jabs so far and around 28 million people in England eligible.
Health Secretary Sajid Javid is calling on people to protect themselves against both viruses after experts predicted high infection rates could push the health service to breaking point.
It comes as colder weather and darker evenings lead to increased social contact indoors, making it easier for the viruses to spread.
The Covid booster must be given no earlier than six months after a second dose of any coronavirus vaccine, according to guidance from the Joint Committee on Vaccination and Immunisation (JCVI).
Health chiefs are urging Britons to get jabbed as soon as possible amid warnings up to 60,000 people could die from flu this winter [Stock image]
Professor Jonathan Van-Tam (pictured), England’s Deputy Chief Medical Officer, said: ‘Not many people got flu last year because of Covid-19 restrictions, so there isn’t as much natural immunity in our communities as usual [File photo]
Millions of people who are eligible for a Covid booster vaccine have not had their third dose yet
Millions of people who are eligible for a Covid booster vaccine have not yet had their third dose, official figures suggest.
Up to 5million people in England currently qualify for a booster jab but only around a third have come forward for one.
It comes after a top Government scientific advisor said he wanted Britain to be ‘more aggressive’ with the rollout to limit the damage of a winter wave of cases.
A total of 1.7million people in England have received a booster since the programme was signed off last month.
Invites are only being sent out to those who received their second dose at least six months ago because that is the ‘sweet spot’ for immunity.
For this reason, the rollout was always expected to be slower than the initial jab blitz, which at its peak saw 800,000 people vaccinated per day.
But official figures show 4.9m people finished their two-dose vaccination schedule six months ago, with the majority meeting the criteria making them eligible for a top-up now.
About 400,000 of the people jabbed half a year ago were immunocompromised and are receiving their third dose on a slightly different schedule. And many people who were vaccinated first originally were elderly and may have passed away in the past six months.
But even when these are discounted, it still leaves millions of eligible and vulnerable people with subpar immunity.
In some regions people may be offered the Covid jab in one arm and the flu vaccine in the other, although this will not be available everywhere.
Mr Javid said people should not delay having either jab when invited to get them – either on separate occasions or at the same time.
He added: ‘The Covid-19 vaccine programme is a fantastic example of how successful vaccination programmes can be – with around 130,000 lives saved.
‘It is vital we continue that incredible progress with all those eligible ensuring they get both their flu and Covid-19 booster injections as soon as they are invited.’
A report from the Academy of Medical Sciences, published earlier this year, assessed how the triple threat of coronavirus, flu and respiratory syncytial virus (RSV) might affect the NHS this winter.
It found that hospital admissions and deaths from flu and RSV could be more than double those seen in a normal year, leading to as many as 60,000 flu deaths and 40,000 children in hospital with RSV.
A recent survey of 3,000 people for ministers found that nearly one third (32 per cent) were unaware that flu and Covid-19 can circulate at the same time.
A quarter (26 per cent) did not know that flu can be fatal and over half (55 per cent) underestimated the number of people who die from flu in an average year in England, which is around 11,000.
Almost one in ten (9 per cent) thought the Covid jab would protect them against flu.
Professor Jonathan Van-Tam, England’s Deputy Chief Medical Officer, said: ‘Not many people got flu last year because of Covid-19 restrictions, so there isn’t as much natural immunity in our communities as usual.
‘We will see flu circulate this winter; it might be higher than usual and that makes it a significant public health concern.
‘Covid-19 will still be circulating and with more people mixing indoors, sadly some increases are possible.
‘For the first time we will have Covid-19 and flu co-circulating.
‘We need to take this seriously and defend ourselves and the NHS by getting the annual flu jab and the Covid-19 booster when called.’
Just a third of people eligible for a Covid booster vaccine in England have had their third dose, official figures suggest. NHS bosses revealed on Thursday that 1.7million people in England have been given a booster since the programme was signed off last month
Government Covid dashboard data shows that by this time six months ago, 4.93m people in England had been double-dosed, which should make them eligible for a booster now
Experts fear a massive surge in cases because social distancing measures kept infections low last year, reducing population immunity [Stock image]
More than 80 per cent of people aged 65 and over had their flu jab last year – exceeding a global target of 75 per cent. The NHS has set an ambition to reach at least 85 per cent of this group this flu season.
It also hopes to reach at least 75 per cent of people with underlying health conditions, such as asthma and heart disease, at least 75 per cent of pregnant women and at least 70 per cent of eligible children.
All frontline health and social care workers will also be offered a flu jab, with an ambition that at least 85 per cent will accept.