The flu jab

Flu vaccination by injection, commonly known as the "flu jab" is available every year on the NHS to protect adults (and some children) at risk of 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 more severe in certain people such as:

  • anyone over the age of 65 
  • pregnant women
  • children and adults with an underlying health condition (particularly long-term heart or respiratory disease)
  • children and adults with weakened immune systems

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

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

Find out more about who should have the flu jab.

Flu nasal spray vaccination

The flu vaccine is given as an annual nasal spray to:

  • children aged two to 18 years at risk of flu
  • healthy children aged two, three and four years years old 

Read more about the flu nasal spray for children.

How the flu jab helps

Studies have shown that the flu jab definitely works and will help prevent you getting the flu. It won't stop all flu viruses and the level of protection may vary 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.

There is also evidence to suggest that the flu jab can reduce your risk of having a stroke.

Over time, protection from the injected flu vaccine gradually decreases and flu strains often change. So, new flu vaccines are produced each year which is why people advised to have the flu jab need it every year too.

Read more about how the flu jab works.

Flu jab side effects

Serious side effects of the injected flu vaccine are very rare. You may have a slight temperature and aching muscles for a couple of days after having the jab, 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 jab

The best time to have a flu vaccine is in the autumn, from the beginning of October to early November, but don't worry if you've missed it, you can have the vaccine later in winter if there are stocks left.

The flu jab for 2013/14

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 2013/14 vaccine protects against three types of flu virus. This year’s flu jab protects against:

  • H1N1 – the strain of flu that caused the swine flu pandemic in 2009
  • H3N2 – a strain of flu that can infect birds and mammals and was active in 2011
  • B/Massachusetts/2 – a strain of flu that was active in 2012

Is there anyone who shouldn't have the flu jab?

Most adults can have the injected flu vaccine, but you should avoid it if you have had a serious allergic reaction to a flu jab in the past.

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.

      The Tokkels: flu jabs

      Flu is a highly infectious illness caused by the flu virus. It spreads rapidly through small droplets coughed or sneezed into the air by an infected person. Some people are at greater risk of developing serious complications of flu, such as bronchitis and pneumonia. The flu vaccination is offered to people in at-risk groups.

      Media last reviewed: 14/11/2013

      Next review due: 14/11/2015

      Page last reviewed: 12/04/2014

      Next review due: 12/04/2016


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      The 9 comments posted are personal views. Any information they give has not been checked and may not be accurate.

      Kathryn at NHS Choices said on 06 January 2014

      Dear ellie590,

      The flu virus changes with time so it's important you keep having the flu vaccine each year. It won't make things worse. There's no evidence that having the jab in any way weakens your protection in subsequent years.

      The flu jab does not provide complete protection so you may still be unlucky enough to get flu, but most likely in a milder form than you would have had without the vaccine.

      Bear in mind, too, that many illnesses that are called “flu” are in fact due to other infections and cannot be prevented, so it may be that in some years you have had an illness like flu but due to a different infection.

      Hope that helps,
      Kathryn, NHS Choices editor

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      ellie590 said on 22 December 2013

      I have the flu jab every year. I have no side effects from the jab, but I also get flu every year, often badly and always leaving me with a bad cough. Is there any point in me keep having the jab and could it actually make things worse? I am 63 years old.

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      fracrecep said on 15 December 2013

      I had the flu jab three weeks ago and my body has not stopped aching, From the bottom of my back right down the backs of my legs, I struggle to move freely, I didn't have this before my flu jab, Now I have just read that this is happening to someone else, I had,nt heard of this being a side effect,
      This is the first time I have had a flu jab,

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      Kevish24 said on 03 December 2013

      I regret not having looked at my injection, Don't be shy to ask or see what is going inside you. The lable on it, the size & type of immunisation it is etc.. We tend not to look at it because we fear the needle.

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      fluent said on 23 October 2013

      I had flu jab on Saturday. Almost immediately the underside of my tongue swelled up and there were lumps at the bottom of my mouth and mouth ulcers developed.
      Since then I have had fever, aching limbs, bad cough and cold, these symptoms continue and it is now Wednesday.

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      Kathryn at NHS Choices said on 11 October 2013

      Dear Spyker,

      It is perfectly ok to have the flu jab while taking antibiotics. I've added to our articles to make this clear.

      Kathryn Bingham (NHS Choices editor)

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      Spyker said on 10 October 2013

      It is very unfortunate indeed that no mention is made in public leaflets or on the health or GP websites that patients who are currently taking antibiotics cannot have the flu vaccination until at least a week after they have their last tablet. I just wasted a solid hour waiting at my GP practice for the reasons stated above. It's high time the NHS is a bit more transparent with its patients and give out factual information in the media as to who can have the flu vaccination and who can't.

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      Tommy57 said on 30 September 2013

      I have had long term asthma which is controlled by a salbutomol inhaler, I have had the flu jab for years and have to attend an asthma clinic for a yearly check up. When I contacted my local practice for my seasonal jab I was informed that it was only people with asthma which is controlled by steroids who are eligible for the flu vaccination. This is not made clear in the public leaflets or information on the web, seemingly a committee are pruning the people who get the injection and information is made available to GPs via the green book? Very strange.

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      crabbsnest43 said on 21 September 2013

      again this year it is the same story when i tried to book our flu jab "to late i was told that is the next day to the day one could phone to book ,told all appointments gone !!!! now i started having flu jabs when in my 50 because i had sarcodoisis so was having the jab well before retiring , when we first moved to Snettisham March the 1st 2001 it was a system of turning up and it was done alphabetically very smooth (it tokk longer to get through the raffle ticket buying ) on exit so i am not a happy bunny at all !! (nor is my husband ) he has chest trouble also so there we are perhaps it might be a good idea to camp outside the surgery for the next release dates !!!

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