We have now entered the cold autumn months and things are only going to get chillier in the lead-up to Christmas.

This has since prompted fears among health officials that millions of Brits are yet to have their flu of Covid jab.

So far 11.7 million have had the flu vaccine and 8.6 million eligible people have taken up the offer of a Covid-19 booster jab.

However, figures from the UK Health Security Agency (UKHSA) show that about 30 million people are eligible for the flu jab and approximately 21.5 million can get the Covid vaccine.

That means less than half have had their jab.

UKHSA said that flu and Covid-19 cases are expected to peak during the festive period as it launched its new Get Winter Strong campaign.

It is hoped the campaign could boost vaccination numbers among people who do not typically come forward when called, including people with health conditions, pregnant women and children aged two and three.

Dr Mary Ramsay, director of immunisation at UKHSA, said: “As the weather turns colder, respiratory viruses spread more easily and usually reach their peak over the festive and new year period.

“For those most vulnerable both flu and Covid-19 can cause severe illness, often hospitalisation.

“Nobody wants to miss out on the festive celebrations with their friends and family this winter and the vaccines provide the best possible protection.

“I urge all those eligible to join the millions of others who have taken up their free vaccine offer to get winter strong – don’t put it off, book your appointment today and arm yourself against the risk of severe illness.”

Steve Russell, national director for vaccinations at NHS England, said: “Getting the flu and Covid-19 vaccines are two of the most important things you can do to protect yourself from serious illness this winter.

“There are thousands of sites open across the country and eligible adults can book both vaccines online or through the NHS App in just a few minutes – if you’re eligible, we’d urge you to get both vaccinations as soon as you can, to help protect yourself and your loved ones and get winter strong.”