The group, comprising of member companies: Abbvie, AstraZeneca, GlaxoSmithKline, Mylan, Pfizer Vaccines, and Takeda aims to work in partnership with the public health community throughout the four nations of the UK to encourage the continued and further success of the national immunisation programmes.

Our strategic priorities are to maintain and build on the success of the immunisation programme in England Advocate for a policy to review, recommend and procure vaccines that are based on sound principles of health technology assessment and recognise the particular characteristics of vaccines and the vaccine environment.

We also wish to maintain partnerships with the public health community to increase the uptake of vaccinations in each of the four nations amongst those who would most benefit, as set out in relevant national and international guidelines

If you would like to contact the ABPI Vaccines Group, please email

For all media enquiries, please email or telephone +44 (0) 20 7747 1410 or +44 (0) 20 7747 1441.

Find out more about our advocate work around seasonal flu vaccinations:



What is seasonal flu?

  • Influenza is an acute viral infection of the respiratory tract.1
  • Symptoms begin with an abrupt on-set of fever (over 38 degrees C) followed by a dry cough, aching joints and muscles, chills and exhaustion. Individuals with flu often have to go to bed because they feel so ill 1,2,3
  • For most people flu is an unpleasant illness lasting around a week, although in severe cases flu can lead to bronchitis, pneumonia and even death.1,2
  • For pregnant women, those with certain chronic illnesses and the elderly flu can be serious 1,3
  • Numbers of deaths from flu are difficult to determine as death is often attributed to another cause such as pneumonia. On average about 600 people a year die from flu in the UK.3
  • Though the virus is present throughout the year, infection peaks annually during the winter months (December to March) in the UK.1,3

How is flu spread?

  • Flu is mainly spread by coughing and sneezing 1,2,3
  • Droplets of saliva and mucus containing the virus are expelled into the air where they are breathed in by other individuals or land on surfaces.1,2,3
  • Flu viruses can live on hard surfaces like desks, telephones, computer keyboards or door handles for several hours 2,3
  • The virus can be transmitted by touching an infected surface and then touching the mouth or eyes 2,3
  • Regular hand washing is an effective way of reducing the transmission of the virus 3

What are the different types of virus?

  • There are three different types of flu virus, types A, B and C 1,2
  • Types A and B are important in human disease, although type A tends to be more serious.2,4
  • Influenza A and B are responsible for most clinical illness. Most common strains of flu causing disease in humans are type B and two strains of type A called H1N1 and H3N2 1,2

How does the virus cause disease?

  • The flu virus penetrates the cells lining the nose and throat and starts to multiply 2,5
  • As the virus replicates, the cells burst, releasing new virus 2,5
  • The dead cells break away, a little like dead skin cells, leaving an inflamed spot which causes tickling and soreness in the nose and throat5
  • If the virus penetrates deep into the lungs it can damage the cells leading to a dry cough and allow access to the lungs by other micro-organisms which can cause bronchitis and pneumonia 1,2,5


  1. Department of Health. Immunisation against Infectious Disease. Chapter 19 (accessed October 2013)
  2. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. Atkinson W, Wolfe S, Hamborsky J, eds. 12th ed., second printing. Washington DC: Public Health Foundation, 2012.
  3. NHS Choices (accessed August 2012)
  4. Health Protection Agency. Seasonal Influenza (accessed September 2012)
  5. University of South Carolina lecture notes (no longer available online)

Adverse Events should be reported. Reporting forms and information can be found here. Adverse events should also be reported to the appropriate pharmaceutical company.


Vaccine manufacture and supply

Flu vaccine manufacture and supply process for inactivated vaccines

The National Influenza Centres are able to analyse and review all of the virus strains that are coming in from around the globe, and can advise the World Health Organization about which ones are most common and which are causing disease.

Flu vaccine

Each year the seasonal flu vaccine contains three different strains of the flu virus1A vaccine containing four different strains became available for the first time for the 2013-14 season 2.

The flu virus for inactivated vaccines is grown in hen’s eggs. After incubation the virus is harvested from the eggs, and then purified to get the live virus. Hundreds of millions of eggs are needed to produce enough flu vaccine for the season2. This can cause a delay depending on the availability of eggs for production.

The next step is to kill the virus, or inactivate it. After this the virus particle is split up and then the three strains are added together, and a buffer solution is added to make the final formulation of the vaccine.

The three strains need to be added together there can be a risk of delay, because the slowest growing strain will dictate how much vaccine you can make.2

Once there is an inactivated vaccine, it is tested in around a hundred healthy individuals. These tests ensure that the vaccine has a good safety profile, and that when vaccinated people produce enough antibodies to fight off the flu should infection occur. Vaccine production involves very rigorous quality assurance and quality control testing. These tests are carried out both by the manufacturer and external agencies.2 All of this means that 70% of the entire vaccine development time is spent on testing.3

The entire process of manufacturing an inactivated vaccine includes reviewing existing production capacity; ordering sufficient pathogen-free eggs to meet production needs; filling, packaging and labelling, prior to supply of vaccine.2

Manufacturing a new vaccine usually takes around two years but for flu vaccines the entire process is compressed into eight months. With such complex and time consuming steps in the process any delay is likely to have a knock on effect, which ultimately impacts on the timing of vaccine availability.123


  1. Department of Health. Immunisation against Infectious Disease. Chapter 19 (accessed October 2013)
  2. Department of Health, Seasonal Flu Plan 2012/13 (accessed August 2013)


Information about the flu virus, symptoms, complications and disease patterns can be found at the following sites.

  • The Department of Health Green Book influenza chapter contains top-line disease information about flu including an explanation of the virus, disease patterns and death rates.
  • NHS Choices provides patients with easy to read, bite-sized chunks of information on the cause, symptoms and treatment of flu.
  • The Department of Health’s Winter Watch campaign brings you regular updates about how the NHS is coping with the increased demands of the cold winter months, levels of flu-like illness and uptake of flu vaccination.
  • Each year, the World Health Organization recommends the flu virus strains that should be used in the vaccine, based on those which are circulating and causing disease around the globe. The WHO recommendations are made in February for the Northern hemisphere and September for the Southern hemisphere.
  • In the UK, Public Health England monitors the level of flu in the population throughout the winter, providing weekly reports on cases, hospitalisation and death rates.
  • In the USA, the Centers for Disease control publish the Pink Book with detailed disease and epidemiology information.

Up-to-date guidelines & advice are available from the Department of Health.

  • The Green Book chapters are updated regularly on-line to reflect current immunisation recommendations.
  • Joint Committee on Vaccination & Immunisation (JCVI) advises National immunisation policy. There is an influenza sub-committee which advises the main committee on matters relating to the monitoring and control of influenza in the UK. The minutes of meetings held by the main and sub-committees can be accessed on the Department of Health website
  • Practical advice for frontline staff delivering the annual flu vaccination campaign is offered via the Chief Medical Officers letters and the Department of Health Seasonal Flu Plan

Product information for flu vaccines & antivirals licensed for use in the UK can be accessed via the electronic Medicines Compendium (eMC).

Adverse Events should be reported. Reporting forms and information can be found here. Adverse events should also be reported to the appropriate pharmaceutical company.


Uptake rates of seasonal flu vaccine 2012/13

Every year the Department of Health (DH) monitors how many people in the recommended groups accept flu vaccination. These groups are 1:

  • Everyone 65 years and over
  • Children over 6 months of age and adults under 65 years in the at-risk groups including people with a weakened immune system or an underlying medical condition such as diabetes or chronic lung, heart, liver, kidney or neurological disease
  • Pregnant women, a new risk group introduced in 2010
  • Healthcare workers who have direct patient contact
  • Children aged two to three years (introduced in 2013)

Overall uptake at the end of the 2012/13 flu season 3:

Group 2012/13 uptake rate
65 years and over 73.4%
At-risk groups under 65 51.3%
Pregnant women 40.3%
Healthcare workers2 45.6%


  1. Public Health England, Influenza Vaccine Uptake amongst GP patient groups in England 2012/13
  2. Public Health England, Seasonal Influenza Vaccine Uptake HCWs 2012/13
  3. Department of Health flu immunisation programme 2013/14 p.17

2013/14 Flu vaccine strains

The trivalent seasonal flu vaccine contains three different strains of the flu virus, two type A viruses and a type B virus. The quadrivalent seasonal flu vaccine contains four different strains of the flu virus, two type A and two type B virus. These vaccine strains change most years depending on which are the common wild virus strains that are circulating and causing disease globally in the preceding months.

The strains selected for the trivalent 2013/14 flu vaccines are:1

  • A/California/7/2009 (H1N1)pdm09-like virus;
  • A(H3N2) virus antigenically like the cell-propagated prototype virus A/Victoria/361/2011b*;
  • B/Massachusetts/2/2012-like virus.

The strains selected for the quadrivalent 2013/14 flu vaccines are:1

  • A/California/7/2009 (H1N1)pdm09-like virus
  • A/Victoria/361/2011 (H3N2) like strain used (NYMC X-223A) derived from A/Texas/50/2012
  • B/Massachusetts/2/2012-like virus
  • B/Brisbane/33/2008 is a B/Brisbane/60/2008-like virus.

*It is recommended that A/Texas/50/2012 is used as the A(H3N2) vaccine component because of antigenic changes in earlier A/Victoria/361/2011-like vaccine viruses (such as IVR-165) resulting from adaptation to propagation in eggs.


How are the flu strains identified each year?

The World Health Organization (WHO) monitors circulating flu virus strains through the Global Influenza Surveillance and Response System. The system involves the collection of samples from throats of individuals presenting at their GP surgery with influenza-like illness. These samples are sent to one of four National Influenza Centres in the UK where they are analysed and identified. 1

The centres pass on the information to the WHO. Information on which strains are most common and which are causing disease is collated by the six global WHO Collaborating Centres for influenza, allowing the WHO to recommend the vaccine strains for the upcoming season.1 The vaccine strains should then be a close match to the circulating virus strains, offering the best chance of protection from infection.


  1. World Health Organisation. Influenza (last accessed July 2013)

Adverse Events should be reported. Reporting forms and information can be found here. Adverse events should also be reported to the appropriate pharmaceutical company.

Date of preparation July 2013



Can the flu vaccine give someone flu?

No, flu vaccines cannot give you flu. Vaccines given by injection contain killed (inactivated) viruses and therefore cannot cause flu.1 Vaccine given by nasal spray contains live virus that has been weakened (attenuated) so that it provokes a full immune response in the body but does not cause flu to develop1.

Common undesirable effects of vaccination such as aching muscles, a fever and headache1 can feel like flu, which is why some people believe the vaccine has made them ill. Importantly these unwanted effects are usually short-lived.1 Also it can take up to two weeks following vaccination for an adequate antibody response to occur.1

It is possible to become infected with a virus that is currently circulating either just before or during the first couple of weeks following vaccination, giving the appearance that the vaccine has caused the infection.

Does the flu vaccine work?

Yes. Every year scientists develop vaccines based on the strain of flu in circulation. The vast majority of times the match is successful and the jab will protect you from the type of flu strain that is circulating. Current flu vaccines give around 59% protection in adults against infection with influenza virus strains 1, with higher protection when the strains are well matched with those in the vaccine, and according to the age and clinical conditions of individuals.2 Reassuringly, vaccination has been shown to be 50% to 60% effective in preventing hospitalisation and 80% effective in preventing death amongst elderly people.1,3

Aren't the side effects of the vaccine worse than the disease?

No. Unlike the common cold, flu can be debilitating even in young, fit and healthy people. The infection causes a range of unpleasant symptoms including a high fever (over 38°C),4 aching muscles, chills, headache, sore throat and extreme tiredness.1,3,4 Most people are unable to carry out basic daily tasks and will probably have to go to bed. These symptoms can last for a few days and some people may have a lingering weak feeling or even depression for several weeks.3

In rare cases people with flu can develop bronchitis4 as the flu virus damages their windpipe and lungs.3,5 Flu can also lead to pneumonia, usually due to bacteria which take advantage of the weakened state of the lungs during a flu infection.1 Both pneumonia and bronchitis can be serious and life-threatening, these individuals may require hospitalisation.

In contrast the most common undesirable effects of vaccination are reactions such as swelling or redness at the injection site.3,4 Some people (between 1% and 10%)6 may complain of low grade fever (37°C to 38°C), tiredness, aching joints & muscles and generally feeling unwell.3,4,6 These symptoms usually disappear within one to two days without any need for treatment 4,6 and are unlikely to interfere with routine daily activities.

Do younger, healthy people get flu or is it only the sick or elderly?

Yes, younger, healthy people do get flu; in fact most cases of flu occur in adults aged 15-64 years.7 For most people it is an unpleasant illness lasting around a week. However, for those with certain chronic illnesses, those who are elderly or those who are pregnant, flu can be serious.

Also many younger people in the risk groups, for example those with well-controlled diabetes or asthma, do not consider themselves to be at unhealthy. However they are at a higher risk of complications from flu than someone the same age without the risk factor.

Is it dangerous to have the flu jab whilst you are pregnant?

No. The Department of Health advises that pregnant women at any stage of pregnancy should be offered inactivated flu vaccine.1 This is standard medical practice in many industrialised countries.8

There is no evidence that the flu vaccine will harm a pregnant women or her unborn baby if she is vaccinated at any stage of pregnancy.2,8 Vaccinating during pregnancy also passes on some protection against flu to the new-born baby in the first few months of their life.1

However catching flu when pregnant increases a woman’s risk of becoming very ill as well as the risk of premature birth and miscarriage.8

Can antiviral drugs be used instead of vaccination to prevent flu?

No. Antivirals are used to treat the symptoms of flu once an individual has been infected.9 They are not designed to prevent infection and therefore cannot replace vaccination. The best way to protect yourself from flu is through vaccination.


  1. Department of Health. Immunisation against infectious diseases – The Green Book. Chapter 19 Influenza (last accessed September 2013)
  2. CMO Letter. The Flu Immunisation Programme 2012/13 (last accessed August 2012)
  3. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. Atkinson W, Wolfe S, Hamborsky J, eds. 12th ed., second printing. Washington DC: Public Health Foundation, 2012.
  4. NHS Choices (last accessed August 2012)
  5. University of South Carolina lecture notes (last accessed August 2012)
  6. Trivalent Inactivated Influenza Vaccine Summary of Product Characteristics.
  7. Meier, CR et al. Population-Based Study on Incidence, Risk Factors, Clinical Complications and Drug Utilisation Associated with Influenza in the United Kingdom. Eur J Clin Microbiol Infect Dis 2000;19:834-842
  8. Health Protection Agency. H1N1 (2009) flu vaccination for pregnant women: frequently asked questions (last accessed August 2012)
  9. World Health Organization. Influenza Fact Sheet (last accessed August 2012)

Adverse Events should be reported. Reporting forms and information can be found here. Adverse events should also be reported to the appropriate pharmaceutical company.