Millions of people aged 50 and over will be able to book a Covid-19 autumn booster jab and flu vaccination from tomorrow - as fears grow about the impact of a 'twindemic' on health services this winter.

The NHS says online and phone bookings will open on Friday for around 12 million people, aged between 50 and 64, to allow them to book a coronavirus jab.

And for the first time the service will allow those eligible for a flu vaccination to also book an appointment through a new pilot scheme - with injections being made available at more than 200 sites across the country.

With Covid-19 cases and hospitalisations rocketing there are fears the UK is already seeing signs of a fresh winter wave of the virus.

Health experts also believe the country is in for a difficult flu season with data from the southern hemisphere, and in particular Australia, pointing to increased case rates and less natural immunity within communities caused by two years of social distancing as a result of the pandemic.

With NHS services already struggling, there are concerns that staffing levels and bed availability could be pushed to breaking point if rising coronavirus admissions coincide with large numbers of people coming into hospital needing treatment for severe flu.

As a result those patients entitled to either a Covid-19 jab or flu injection - or both - are being encouraged to come forward and book their appointments.

More than 7 million people have already had their autumn booster in just over a month, says the NHS, following a bumper week last week when almost two million jabs were given to people aged 65 and over and those most at risk from Covid-19.

Those entitled to a free flu jab on the NHS, who may not yet be eligible for a Covid-19 booster, can still book their flu immunisation either through their GP or by visiting a participating pharmacy. Anyone who is unsure of the procedure should call 119 for help.

NHS Chief Executive Amanda Pritchard said: “Thanks to the incredible work of our frontline staff across the country, our Covid autumn vaccination programme continues to go from strength to strength as we open up eligibility to around 12 million more people from tomorrow.

"The rollout is off to a flying start – we have invited twice as many people as we did last autumn and we have jabbed twice as many people as we did last autumn.

"As we approach what could be an extremely challenging winter for the NHS, it is vital to get your protection against both Covid and flu so please come forward and book in when you can."

In total, around 33 million people in England will be offered a free flu vaccine this year.

Alongside people over 50, pregnant women, patients with underlying health conditions, those in care homes and health care workers, millions of pupils in both primary and secondary school will also be offered the nasal spray via community health teams visiting classrooms.

While sites are co-administering the flu and Covid vaccines for adults where possible, people may be required to book two separate appointments for the different vaccines in some instances.

Chief Medical Advisor at the UK Health Security Agency Dr Susan Hopkins said: "The double threat of widely circulating flu and Covid-19 this year is a real concern, so it’s crucial that you take up the free flu vaccine as soon as possible if you are offered it. It will help protect you from severe flu this winter, and even save your life.

"All those over 50 are now eligible for the jab, many of which will have low natural immunity due to Covid-19 restrictions over the last two years."