Health officials are ramping up efforts to ensure everyone who needs a flu vaccine has one.
The UK’s largest flu-immunisation programme so far will see 30 million people in England offered the vaccine.
The idea is to prepare for a winter that could see the annual flu season coincide with a surge in coronavirus.
But how will it work? And will things be worse this year?
How bad is flu?
The flu – or influenza – is a very common, highly infectious disease, caused by a virus.
It can be dangerous – particularly for older adults, very young children, and people with underlying health conditions.
The average number of estimated deaths in England for the past five annual flu seasons is more than 11,000.
This ranges from almost 4,000 deaths in the season spanning 2018-19 to more than 22,000 in 2017-18.
The problem is certain groups of people, such as older people, pregnant women and people with long-term conditions are at high risk of becoming seriously ill from both coronavirus and flu.
And while many healthy people can fight off the flu, sometimes things are more complicated.
The most common complication is a bacterial chest infection, which can develop into pneumonia.
Other life-threatening complications include meningitis and septic shock.
How bad are flu and coronavirus together?
There is some evidence a double infection with coronavirus and flu is more deadly than either alone.
But others believe being infected with one virus could potentially help prevent another virus from making someone ill at the same time.
What is clear is a big flu season combined with coronavirus could overwhelm hospitals
For example, if lots of NHS or care-home staff are sick with flu, it may not be possible to respond to Covid-19 in the same way as during the peak in spring.
But social distancing, masks and other hygiene measures in place to stop coronavirus should, in theory, also have an impact on the amount of flu going around.
How do you know if you have flu or coronavirus?
Both flu and coronavirus can cause a fever, cough, tiredness, muscle aches and headaches.
Some people – mostly children – have other symptoms such as diarrhoea and vomiting.
Some of these symptoms are also seen when people are ill with other common winter viruses.
And both flu and coronavirus can be spread before people have any symptoms or by people who do not get symptoms at all.
This could make things difficult this winter.
And that is why the flu vaccine is being offered more widely and testing and tracing facilities for coronavirus are increasing.
Who will be offered the flu vaccine?
In England, it will be offered free to:
- people who were required to shield from coronavirus – and anyone they live with
- people with some medical conditions, including diabetes, heart failure and asthma
- pregnant women
- pre-school children over the age of two
- all primary school children, as last year, and, for the first time, Year 7 pupils
- initially, all people over 65, before the programme is extended to the over-50s
- healthcare and social care staff
Health officials in Scotland, Northern Ireland and Wales are planning to expand their vaccination programmes to cover similar groups.
The NHS wants to ensure the highest-risk patients are at the front of the queue when the immunisation programme starts, in September.
The aim is for people aged 50-64 to be offered the jab later, in November or December, if there are enough supplies.
Officials also say it is essential to increase vaccination levels among people in the most deprived areas and for people belonging to ethnic minorities at high risk of both Covid-19 and flu .
The vaccine will also be available privately in pharmacies and some supermarkets to adults ineligible for an NHS jab.
It usually costs about £20.
Will it be harder to get the vaccine this year?
Doctors and nurses are being asked to put new measures in place to allow the vaccine to be given safely during the pandemic.
This will include careful appointment times to minimise waiting.
Extra staff may be brought in to help.
Some GP surgeries may ask people to use their cars as waiting rooms.
Others will consider drive-through clinics.
For the most vulnerable, there are suggestions nurses could visit them at home.
And some pregnant women may be offered jabs during antenatal appointments.
Meanwhile, people isolating because they or someone they have been in contact with have coronavirus will be asked to postpone their vaccinations until they are better.
Are there enough supplies?
The Department of Health and Social Care says it has additional national supply of the adult vaccine to ensure demand does not outstrip supply.
Is it the right vaccine?
Every year, the World Health Organization studies circulating flu strains to make recommendations for the next season’s vaccines.
This can only ever be a prediction, as vaccines have to be made in advance – often six months before the virus starts circulating in a country.
While experts agree this is not always 100% accurate, they say it is better to be vaccinated against some strains of flu than none at all – particularly during a pandemic.