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					                   Swine flu vaccination
                   Standard Note:    SN/SC/5164
                   Last updated:     3 February 2010
                   Author:           Dr Gavin Colthart
                   Section           Science and Environment Section

This note is supplementary to the Standard Note, Pandemic influenza and swine flu


1    Vaccine development and regulatory approval                                             2

2    Vaccine safety concerns                                                                 3

3    Liability for harm caused by vaccines                                                   3

4    Powers to impose compulsory vaccination                                                 4

5    UK swine flu vaccination programme                                                      5

This information is provided to Members of Parliament in support of their parliamentary duties
and is not intended to address the specific circumstances of any particular individual. It should
not be relied upon as being up to date; the law or policies may have changed since it was last
updated; and it should not be relied upon as legal or professional advice or as a substitute for
it. A suitably qualified professional should be consulted if specific advice or information is

This information is provided subject to our general terms and conditions which are available
online or may be provided on request in hard copy. Authors are available to discuss the
content of this briefing with Members and their staff, but not with the general public.
1       Vaccine development and regulatory approval
Since the avian flu outbreaks from 1997 onwards, vaccine production capacity has increased
but the technology remains relatively slow. The virus responsible for the current swine flu
outbreak was isolated and prepared for the first stages of vaccine production on 19 May
2009, a process in which the HPA’s National Institute for Biological Standards and Control
(NIBSC) played a key role.

In recognition of the possible future need to secure supplies of new vaccines during a
pandemic, the DH had entered into ‘sleeping contracts’ with two manufacturers (Baxter and
GlaxoSmithKline, GSK). The contracts reserved 132 million doses of any vaccine developed
against a pandemic flu strain and took effect once WHO declared a phase 6 pandemic. Due
to concerns about the rising number of cases in the UK, the DH also entered into preliminary
contracts with GSK and Baxter on 15 May 2009 to deliver 90 million doses of swine flu
vaccine. Further background information on vaccine development can be found in the POST
Note, H1N1 ‘Swine Flu’ Vaccine and in a briefing for the HPA Board. 1

Any medicines derived from biotechnology or other advanced technologies require approval
by the European Medicines Agency (EMEA). Normally, approval requires extensive
documentation of product characteristics, manufacturing processes and clinical safety and
effectiveness. This process can take years from the time of development of a new medicine.

In response to the risk of a flu pandemic, a procedure was established to speed up EMEA
regulatory approval of any new vaccine. This allowed manufacturers to submit dossiers
based on available similar flu vaccines, substituting the swine flu component once it was
available. This in turn allowed the EMEA to start its assessment process as soon as possible
but also allowed for the later inclusion of data from clinical trials. According to the EMEA:

        Four ‘mock-up’ vaccines developed by Baxter, GlaxoSmithKline and Novartis have
        already been approved in the European Union based on earlier data generated with
        the H5N1 virus strain, which is similar to H1N1. These vaccines were developed in the
        knowledge that the virus strain would be changed in the event of a declared pandemic,
        to include the strain causing the pandemic. Altogether, they have been tested in more
        than 8,000 subjects. Decades of experience with seasonal influenza vaccines indicate
        that insertion of a new strain in a vaccine, as will apply with the change from H5N1 to
        H1N1 in the mock-up vaccines, should not substantially affect the safety or level of
        protection offered. 2

The two vaccines being used in the UK, Pandemrix (GlaxoSmithKline, GSK) and Celvapan
(Baxter), were approved on this basis. Both new vaccines were the subject of further
research by the manufacturers but by the time of approval these had only been able to
assess their early safety and effectiveness in provoking a useful immune response. 3 4

Studies have also appeared in the academic literature. During September 2009 two studies
in adults were published in the New England Journal of Medicine (NEJM), using subjects in
the UK and Australia. Both suggested the vaccine was effective and produced only the

    HPA, Health Protection Agency Board Meeting 24 June 2009
    EMEA, European Medicines Agency review of pandemic vaccines underway, 24 July 2009
    GSK, H1N1 Press releases [at 10 November 2009]
    EMEA, European Medicines Agency recommends authorisation of additional vaccine for influenza pandemic
    (H1N1) 2009, 2 October 2009

expected level of immediate reactions, with one study showing good levels of immunity after
only one dose. 5

In the UK, the Medicines and Healthcare Products Regulatory Agency (MHRA) has
established a system of enhanced surveillance as the vaccine programme proceeds and
studies are planned of the first 9000 people to be vaccinated with each brand of vaccine. 6

Further information on testing and approval of the vaccines can be found on the EMEA and
MHRA websites.

2        Vaccine safety concerns
Anti-vaccine activists and others have opposed widespread use of any new vaccine, arguing
that the accelerated clinical testing of the new vaccines makes it difficult to ensure safety and
that the generally mild course of novel H1N1 flu infection does not justify exposing the
population to vaccine-related risks. 7

Particular concern has been raised regarding Guillain-Barré syndrome, a nerve disease
causing reversible paralysis, which has been associated with flu vaccinations. A rise in cases
of Guillain-Barré syndrome resulted in the cessation of a 1976 national flu vaccination
programme in the USA. Analysis of the data from that time, and several subsequent studies,
suggest that there is a small rise in the incidence of the syndrome (between 1:100,000 and
1:1,000,000). 8

However, there is also evidence that flu infection itself may be a trigger for Guillain-Barré
syndrome and that this risk may be greater than the risk from vaccination. 9

In the absence of clear evidence on the balance of risks and benefits relating to adverse
events such as Guillain-Barré syndrome, WHO have advised intensive surveillance for any
side effects during and after any vaccine programme. In the UK the HPA announced an
enhanced surveillance programme specifically for Guillain-Barré syndrome. 10 11

At the time of writing, the levels of adverse effects relating to the swine flu vaccines were felt
to be no higher than expected and there did not appear to be any evidence of an increased
incidence of Guillain-Barre syndrome. At 21 January 2010 approximately 4 million people
had been vaccinated in the UK and 38 Million vaccins doses had been given across
Europe. 12

3        Liability for harm caused by vaccines
Government has taken on liability for any potential vaccine-related harm as part of the
original advance purchase agreements with manufacturers. This is explained in a reply by

     NEJM, Online First September 10, 2009, from the New England Journal of Medicine [at 10 November 2009]
     Department of Health, Clinical Professionals Brief on Swine Flu Vaccination, 28 October 2009, p 12
     Halvorsen R, Comment: Mass flu vaccination would be madness, Times, 22 July 2009
     CDC, General Questions and Answers on Guillain-Barré syndrome (GBS) [at 17 September 2009]
     Price L, Should I have an H1N1 flu vaccination after Guillain-Barré syndrome?, BMJ, 12 September 2009,
     Volume 339, p 635
     WHO, Safety of pandemic vaccines [at 17 September 2009]
     HPA, Enhanced Surveillance of Guillain-Barré syndrome during the swine influenza pandemic [at 17
     September 2009]
     HPA, UK Suspected Adverse Reaction Analysis - Swine Flu (H1N1) Vaccines – Celvapan and Pandemrix, 21
     January 2010

the Scottish Government Chief Medical Officer of Health Public Health Division to a Scottish
Freedom of Information request (FoI/09/01147):

         The UK Government, on behalf of the four administrations, signed advance purchase
         agreements in June 2007 and accepted liability for the safety of any vaccines that
         would be produced as a contingency. All governments signing up to an advance
         purchase agreement were expected to provide an indemnity for the vaccine and
         neither manufacturer would sign the contracts without it. The Government's decision
         was based on the best procurement and legal advice. Accepting liability in this way is
         in line with Government accounting rules and was cleared by the Public Accounts
         Committee at the time. The A (H1N1) vaccines that will be used in Scotland and the
         UK will be subject to the licensing and regulation requirements for any new vaccines.
         We will only use influenza A (H1N1) vaccines if we have confidence in their safety. 13

From 10 October 2009, the H1N1 swine flu vaccine was added to the list of vaccinations
covered by the Government’s Vaccination Damages Payment Scheme, which provides
payments of £120,000 tax free in cases of proven vaccine damage. 14

4        Powers to impose compulsory vaccination
Most legal powers needed to manage a pandemic are provided under the Public Health Acts
covering England, Wales, Scotland and Northern Ireland, which empower local authorities to
require examination, hospitalisation, or isolation of infected persons, create a criminal
offence relating to exposing others to risk of infection, and allow some controls over school
attendance and playgrounds. 15

In other words, although local authorities cannot force people to be vaccinated under those
powers, they can for example refuse to admit children to school unless they have been

However, the Government has extremely broad powers for tackling an emergency, in the
Civil Contingencies Act 2004. This includes a special procedure for making regulations in an
emergency, if existing legislation could not relied upon without the risk of serious delay, and
various other conditions are met.

In particular:

         22 Scope of emergency regulations

         (1)     Emergency regulations may make any provision which the person making the
         regulations is satisfied is appropriate for the purpose of preventing, controlling or
         mitigating an aspect or effect of the emergency in respect of which the regulations are

         (2)   In particular, emergency regulations may make any provision which the person
         making the regulations is satisfied is appropriate for the purpose of—

         (a)    protecting human life, health or safety,

         (b)    treating human illness or injury,

     Scottish Government Chief Medical Officer and Public Health Directorate, H1N1 Vaccine Immunity from
     Prosecution, 11 September 2009
     Department of Health, The H1N1 swine flu vaccination programme 2009-2010, 30 September 2009
     Department of Health, Pandemic Flu: A national framework for responding to an influenza pandemic, p 12

Thus, if the situation became serious enough for compulsory vaccination to be considered
necessary, regulations could be introduced under the Civil Contingencies Act 2004 and these
could include penalties for non-compliance.

5        UK swine flu vaccination programme
Details of the UK swine flu vaccination programme were announced on 13 August 2009,
based on recommendations from the Joint Committee on Vaccination and Immunisation
(JCVI) and the Scientific Advisory Group for Emergencies (SAGE). This outlined the priority
groups for early vaccination:

         The following groups will be prioritised in this order (numbers given are approximate
         and are for England only):

              1. People aged over six months and under 65 years in current seasonal flu
                 vaccine clinical at-risk groups (about 5 million people).

              2. All pregnant women, subject to licensing conditions on trimesters (about 0.5
                 million people).

              3. Household contacts of people with compromised immune systems e.g. people
                 in regular close contact with patients on treatment for cancer (about 0.5 million

              4. People aged 65 and over in the current seasonal flu vaccine clinical at-risk
                 groups (about 3.5 million people). This does not include otherwise healthy over
                 65s, since they appear to have some natural immunity to the virus.

         Vaccination of frontline health and social care workers (approximately 2 million people)
         will begin at the same time as the first at-risk group, and will continue for as long as
         necessary. This group is at increased risk of infection and of transmitting that infection
         to susceptible patients. Protecting these people will help the NHS workforce to remain
         resilient and able to treat sick patients.

         Preparations continue to be made to extend the programme beyond these initial
         priority groups, and the Joint Committee on Vaccination and Immunisation will consider
         this matter further and report back in due course. 16

The vaccination programme was started on 21 October 2009, initially confined to the priority
groups above, including front line health workers. GP practices are the main route for
identifying those at risk and administering the vaccine. The programme was subsequently
extended on 8 December 2009 to include all children between 6 months and five years of
age. 17

Most patients receive a single dose of Pandemrix, the vaccine developed by
GlaxoSmithKline. Two doses were initially recommended in children and for those with poorly
functioning immune systems. The advice for children was later modified on the basis of new
research showing that a single dose was adequate to produce immunity. 18

     DH, Pandemic vaccine priority for most at risk [at 17 September 2009]
     DH, Swine Flu Vaccinations for under fives to start before Christmas , 8 December 2009
     DH, A (H1N1) swine flu influenza: phase two of the vaccination programme; children over 6 months and under
     5 years: dosage schedule update, 15 December 2009

Some patients may receive Celvapan, manufactured by Baxter, which is given as two
doses. 19

The number of swine flu cases, hospitalisations and deaths fell after the first wave of the
pandemic (April to September 2009) and the statistics over the early winter (November 2009
to January 2010) showed levels of influenza similar to the expected seasonal flu rise.
Although this suggests that a marked second wave in winter is unlikely, the Chief Medical
Officer stressed the need to continue vaccination of at risk groups, despite a drop in take up
of vaccination offers by GPs and increasing media comment suggesting the Government had
over-reacted to the swine flu threat:

         It is extremely important that we do not allow the current low levels of influenza like
         illness and the stand down of the NPFS [National Pandemic Flu Service] to lead to a
         sense of complacency.

         There is still considerable uncertainty about how the virus will behave over the coming
         months and years. Experts advise us that it is likely that pandemic H1N1 (2009) will be
         the predominant ‘flu virus in the 2010 influenza season. The 2010 season may come
         earlier than usual and there may be outbreaks sparked by returning travellers from
         countries affected by the Southern Hemisphere ‘flu season which starts quite soon.

         There is also a risk that the genetic composition of the pandemic H1N1 (2009) virus
         will “drift” during its passage through the world and return to the United Kingdom to
         cause a more severe illness.

         Currently, many people have felt reassured by the fall in disease incidence, and the
         relatively mild self-limiting illness that has characterised most people’s infections.
         However, when the virus does return, even without any genetic “drift”, deaths and
         hospitalisations cannot be taken lightly since the illness is now vaccine-preventable.

         Deaths, however small relative to previous pandemics, are tragedies for families and
         could, with vaccination, be avoided. 20

Further updated information on the vaccination programme can be found on the DH website.

     DH, Swine Flu vaccines start today, 21 October 2009
     Chief Medical Officer, Pandemic H1N1 (2009) Influenza, 27 January 2010


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