The country-wide vaccination drive kicks off this weekend with those eligible for their free flu jab being urged to get vaccinated now to get protected before the festive period – with the vaccine usually taking two weeks to be fully effective.

In addition, local teams will be hosting pop-up clinics across shopping centres, high streets, football clubs and soft play areas over the next week.

There has been 15.4 million flu vaccines delivered since this season's rollout kicked off, with 2.4 million appointments running across the next week.

Duncan Burton, chief nursing officer for England, said: ‘Flu has hit us early this year and we've just faced the first cold snap of the season which can be dangerous for those over the age of 65 or with pre-existing health conditions.

‘NHS staff across the country are working flat out to protect as many people as possible from flu ahead of winter – hosting pop-up clinics closer to home and on the high street – so it is vital the public come forward for one of the 2.4 million appointments running next week, as getting your jab remains the best way to shield yourself from getting seriously ill.

‘Catch a bargain not a bug this winter - and find your nearest pop-up clinic via your NHS regional webpage for when you're out and about, or as usual you can check your local pharmacy for their drop-in service, book an appointment online or by calling 119, or speak to your GP practice today about your winter flu vaccine.'

Those eligible include people aged 65 and over, those in clinical risk groups and close contacts of those who are immunosuppressed, pregnant women and children, care home residents and carers, frontline social care workers, and health and social care staff.

Secretary of state for health and social care, Wes Streeting, said: ‘This is just one of the steps we've taken to prepare the health system for the colder months – including stress testing winter plans, making sure community teams have the vaccines they need, and identifying patients most vulnerable in winter.

‘Getting vaccinated now protects you, your loved ones, and helps our NHS through the challenging winter months ahead.'

Meanwhile, UKHSA's first Cold-Health Alert of the season has reminded the public that cold weather can have a serious impact on health.