NHS Choices

The flu vaccine

Flu vaccination is available every year on the NHS to people at risk of becoming very ill with flu to protect against flu and its complications.

Flu can be unpleasant, but if you are otherwise healthy it will usually clear up on its own within a week. However, flu can be serious, and every year flu kills.

Flu is likely to be more severe in certain people, such as:

  • anyone aged 65 and over
  • pregnant women
  • children and adults with an underlying health condition (particularly long-term heart, liver, kidney or respiratory disease)
  • children and adults with weakened immune systems
  • anyone who has had stroke or a mini stroke

Anyone in these risk groups is more likely to develop potentially serious complications of flu, such as pneumonia (a lung infection), so it's recommended that they have a flu vaccine every year to protect them.

The annual flu vaccine is given free on the NHS as an injection to:

  • adults aged 18 and over at risk of complications from flu (including everyone aged 65 and over)
  • children aged six months to two years at risk of complications from flu

Find out more about who should have the flu vaccine.

The annual nasal flu spray vaccination is routinely given this flu season to:

  • children aged two and three years old (age on 31 August 2017)
  • children in reception class and school years 1, 2, 3 and 4 in primary school.
  • children aged two to under 18 years at a particular risk of flu and its complications due to a long term health condition

How effective is the flu vaccine?

Every year the World Health Organization (WHO) predict what strains of flu will be circulating the following winter. Most years it is well matched and there is good protection. Flu vaccine is the best way to protect against flu.

Protection against this unpredictable virus is important as it can cause unpleasant illness in children and sometimes severe illness and even death, this is most likely among at-risk groups, including older people, pregnant women and those with an underlying health condition.

Studies have shown that the flu vaccine is still the best way to protect against flu . It won't stop all flu viruses and the level of protection may vary between years, and between people, so it's not a 100% guarantee that you'll be flu-free, but if you do get flu after vaccination it's likely to be milder and shorter-lived than it would otherwise have been.

It’s important to have the vaccine every year as over time, the protection from flu you get form your flu vaccine decreases and flu strains often change. So new flu vaccines are produced each year which is why people advised to have the flu vaccine need it every year.

Flu vaccine side effects

Serious side effects from flu vaccines are very rare. You may have a slight temperature and aching muscles for a couple of days after having the vaccine, and your arm may be a bit sore where you were injected.

Read more about the side effects of the flu jab.

When to have a flu vaccine

The best time to have a flu vaccine is before flu starts to circulate. Ideally this is in the autumn, from the beginning of October, but don't worry if you've missed it, you can still have the vaccine later in winter if there are stocks left. Ask at your GP surgery or community pharmacy.

The flu vaccine for 2017/18

Flu vaccines contain 3 or 4 strains. Each year, the viruses that are most likely to cause flu are identified in advance and vaccines are made to match them as closely as possible. The vaccines are recommended by the World Health Organization (WHO).

The WHO has announced that the 2016/17 flu vaccines will protect against:

  • an A/Michigan/45/2015 (H1N1)pdm09-like virus;
  • an A/Hong Kong/4801/2014 (H3N2)-like virus; and
  • a B/Brisbane/60/2008-like virus.

The vaccines that  protect against four strains also contain

  • a B/Phuket/3073/2013-like virus.

Is there anyone who shouldn't have a flu vaccine?

Most adults can have a flu vaccine, read more about who shouldn't have the flu vaccine.

You can find out more by reading the answers to the most common questions that people have about the flu vaccine.



Click here to see all vaccination leaflets.

Last Updated: 01/04/2017 09:00:00