Millions of people entitled to flu or Covid-19 vaccines are being encouraged to get their jab as soon as possible amid fears that a 'twindemic' is going to strike the UK this winter.

Health officials are concerned the colder months will encourage a resurgence of Covid-19 just as the country's flu season takes off, potentially wreaking havoc in the NHS which is still attempting to get services back on track after previous waves of coronavirus.

People's natural immunity and resilience to flu, particularly among the young, is thought to have been severely dented in the last two years as a result of long periods of social distancing and lockdown that has meant fewer cases of the virus have consequently been in circulation.

Data from Australia, which experiences it's flu season during the UK's summer and can prove a helpful indicator in predicting UK case rates, also suggests strains of the flu virus will circulate more widely this year, with particular concern about the H3N2 strain known to cause more severe illness.

The country has seen around 220,00 laboratory-confirmed cases of flu so far this year - a figure which health chiefs have said is significantly higher than normal.

Dr Susan Hopkins, chief medical advisor for the UK Health Security Agency, explained: "There are strong indications we could be facing the threat of widely circulating flu, lower levels of natural immunity due to less exposure over the last three winters, and an increase in Covid-19 circulating with lots of variants that can evade the immune response."

Around 26 million people are entitled to a Covid-19 booster jab this autumn, including people who are over 65 and those with underlying health conditions.

Aware that the NHS could be faced with both rising flu and Covid cases simultaneously, vaccination hubs are also attempting to deliver flu jabs to those who are entitled at the same time.

NHS director of vaccinations and screening Steve Russell said those who are able to claim an additional Covid-19 jab ahead of the winter should do so.

He said: "There is no room for complacency in keeping Covid-19 on the backfoot, and this autumn booster will help protect those most at risk. Those aged 65 and over, pregnant women and carers are now able to get their jab. If you are one of those eligible, it is as important as ever to get your next dose, so please do come forward as soon as possible."

Just last week a Kent health boss warned that remote working, social distancing and testing hubs may have to be brought back if a 'twindemic' were to hit.

Kent County Council's public health director, Dr Anjan Ghosh said a worse than usual flu season was now on the cards while the risk of another Covid wave was a distinct possibility.

Dr Ghosh said: "The coronavirus outlook is further complicated, potentially, by the twindemic.

"What is happening in Australia is a good predictor for what could happen in England."