Important information about swine flu

Read the latest official advice to help protect yourself, your family and others.

Last updated 12:44 PM Friday 06 November 2009

Swine flu

Information on the swine flu vaccine 

The swine flu vaccination programme began on 21 October 2009, with the highest-risk groups being offered the vaccine first.

If you have any questions about the swine flu vaccine or about receiving the vaccination, please read this page carefully.

This page explains who will get the swine flu vaccine and why, the vaccination programme, effectiveness of the vaccine, and safety issues.

Who will get the vaccine?

The groups of people who are most vulnerable to serious illness from swine flu will be offered the vaccine first. In order of priority, these are:

  • People aged between six months and 65 years in the seasonal flu vaccine at-risk groups (listed below).
  • All pregnant women.
  • People who live with someone whose immune system is compromised (for example, people with cancer or HIV/AIDS).
  • People aged 65 and over in the seasonal flu vaccine at-risk groups.

Frontline health and social care workers will also be offered the vaccine at the same time as the first clinical at-risk groups. Health and social care workers both have an increased risk of catching swine flu and of spreading it to other at-risk patients.

The seasonal flu vaccine at-risk groups are people with:

  • Chronic lung disease, such as chronic obstructive pulmonary disease (COPD), chronic bronchitis and cystic fibrosis. Also included are people with severe asthma who need to continuously or repeatedly use their inhaler or take steroid medication, or who have been admitted to hospital because of their asthma.
  • Chronic heart disease, including heart failure, congenital heart disease, and heart disease caused by high blood pressure.
  • Chronic kidney disease, such as kidney failure and people who have had a kidney transplant.
  • Chronic liver disease, such as cirrhosis and chronic hepatitis.
  • Chronic neurological disease, such as stroke, Parkinson's disease, cerebral palsy, motor neurone disease or multiple sclerosis.
  • Diabetes.
  • Immunosuppression (a suppressed immune system), due to disease or treatment. This includes people who have a damaged or no spleen, people having chemotherapy or other immunosuppressant treatment, and those on high doses of steroid medication.

Healthy people aged over 65 are not a swine flu priority group as they appear to have some natural immunity to the swine flu virus. Surveillance has shown fewer swine flu cases in people over 65 than in younger people.

While children are disproportionately affected by swine flu, the majority make a full recovery. Therefore the experts do not advise that children (other than those in at-risk groups) should be vaccinated initially.

Babies under six months cannot be vaccinated because the flu vaccines do not produce enough of an immune response in them to provide protection.

Pregnant women, however, are a priority group as they are more vulnerable to complications following swine flu infection (see Advice for pregnant women).

If you are in a priority group for the swine flu vaccine, you will be contacted by your local NHS.

What about the rest of the population?

The Joint Committee on Vaccination and Immunisation (JCVI) has advised that the use of the vaccine in the wider healthy population should depend on how the pandemic evolves and on emerging clinical data on the use of the vaccine.

Enough vaccine has been ordered for the whole population, and its use will be kept under review.

The vaccination programme

The swine flu vaccination programme began on 21 October 2009. 

The vaccine is being delivered in phases as stocks become available, with high-priority groups getting the vaccine first.

The government hopes that most of the priority groups will be offered the vaccine by December.

Approximately 50 million double doses of the vaccine are expected by December, with more following after that.

Enough needles and syringes to mix and administer the vaccine will be provided to primary care trusts free of charge. Stocks will be delivered to PCTs, for onward distribution to GPs, before the vaccine arrives.

Vaccination is not compulsory. As with any vaccination, everyone has a right to refuse it.

The swine flu vaccine can be given at the same time as other vaccines, including the seasonal flu jab. If you are normally advised to have the seasonal flu vaccine each winter, you need to continue to receive this every year to ensure that you are protected against most of the flu strains in circulation.


The following vaccination schedule is recommended in the UK:


  • For children aged from six months to nine years:
    - two half doses (0.25ml each) given with a
      minimum of three weeks between doses.
  • For individuals aged 10-59:
    - one dose (0.5ml) given.
  • For individuals aged 60 years and over:
    - one dose given (this advice will be reviewed
      when more data become available).
  • For individuals aged 10 years and over with weakened immune systems:
    - two doses (0.5ml each) given
      with a minimum of three weeks between


  • For children aged from six months and adults:
    - two doses (0.5ml each) given with a 
     minimum of three weeks between doses. 

This dosage schedule is based on advice given by the Joint Committee on Vaccination and Immunisation, following consideration of clinical data available on the vaccines. The dosage and recommendations will be kept under review as more clinical data become available.

Effectiveness of the vaccine

Seasonal flu vaccines give around 70-80% protection against infection with flu virus strains. Because the swine flu vaccines are an exact match to the swine flu strain that is currently circulating, they should give at least this amount of protection.

The government will be able to to measure the effectiveness of the swine flu vaccines once they are in use against swine flu.

The swine flu prototype vaccines have been clinically tested and shown to produce good immune system responses, and have an acceptable safety profile. The insertion of the H1N1 strain into the vaccine should not substantially affect the safety of the vaccine in the same way that annual modifications to the seasonal flu vaccine do not (see About the seasonal flu vaccine).

The swine flu vaccine should provide protection against the pandemic strain of swine flu for several years following vaccination. As well as offering protection against the serious effects of swine flu, it may also help to reduce the spread of the infection.

Safety issues

The government takes decisions about introducing a new vaccine very seriously. Vaccines would not be licensed if they were considered unsafe.

Similar flu vaccines containing a different flu virus strain (H5N1) have been clinically tested and the trials showed that these vaccines are safe and produce enough antibodies to provide protection.

Experience with seasonal flu vaccines has shown that changing the strain of virus in a vaccine does not substantially affect the safety profile of the vaccines.

But, as with any new vaccine, some very rare side effects cannot be identified or excluded until the swine flu vaccines are used in much larger numbers of people in the general population.

Outcomes of trials to date suggest that pandemic vaccines are as safe as seasonal flu vaccines.

Pregnant women

There is no evidence that inactivated vaccines, such as the swine flu vaccine, will cause any harm to pregnant women or their unborn baby. Every year, the seasonal flu vaccine is given to pregnant women who are at risk of seasonal flu.

The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency has given a clear recommendation that the GlaxoSmithKline vaccine Pandemrix can be given safely to all pregnant women.

The Department of Health have recently published an information briefing on vaccination and pregnancy.

For more information and advice see 'Vaccination and pregnancy'.

More on the vaccine:

Why are pregnant women in one of the priority at-risk groups for vaccination?

Is the vaccine safe for people with an egg allergy?

What are the ingredients in the vaccine?

Will the vaccine still provide people with protection if the virus mutates?

How will private practices get the vaccine to immunise their private patients?

Is there a link between Guillain-Barre syndrome and swine flu vaccines?

Last reviewed: 09/11/2009

Next review due:

What are these?

vinopalumbo said on 07 November 2009

My 4-year-old asthmatic son had the Pandemrix vaccine nearly two weeks ago. I was expecting some kind of reaction, so was not surprised by his temperature and vomiting in the couple of days that followed. However, in the last 4-5 days he has been quite hyperactive and out of control. I can't be completely sure that it's a result of the vaccine, but has anyone else had a similar experience?

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vinopalumbo said on 07 November 2009

My 4 year old asthmatic son had the vaccine nearly 2 weeks ago. The immediate reactions were a slight temperature and vomiting. This didn't cause great concern and passed within a couple of days. However, he has been hyperactive and quite out of control for the last 4-5 days. Could this be a side effect of the vaccine? Has anyone else had similar problems?

Report this content as offensive or unsuitable

Swine flu vaccines

The swine flu vaccine manufactured by GlaxoSmithKline is called Pandemrix. The vaccine manufactured by Baxter is called Celvapan.

Vaccination leaflet

For a downloadable leaflet summarising information on the swine flu vaccination, go to Swine flu: what you need to know