It's Just a Coincidence That People
Die After The Swine Flu Vaccine
Six people in Britain can be expected to die suddenly after having
the swine flu vaccine but it will just be coincidence, researchers
have said.
With millions of people being vaccinated against the virus there
is a real risk that coincidental events will be seen as reactions
to the jab, a paper in The Lancet said.
Experts at Cincinnati Children's Hospital in America calculated
the background rate of conditions that may be mistaken for vaccine
reactions and warned that there is a risk people will shun the
jab needlessly.
Only if these background rates are exceeded will it point to
a potential problem with the vaccine.
Medical experts have been told to watch for any cases of Guillain-Barré
syndrome during the flu pandemic as some research suggested there
was a link between a flu vaccine used in America in 1976 and the
condition, in which the body’s immune system mistakenly attacks
part of the nervous system and can be fatal in rare cases.
However flu itself it also linked to the condition and about
one in every 100,000 people a year.
Dr Steven Black and colleagues calculated that if 10 million
people in Britain were vaccinated there would be around 22 cases
of Guillain-Barré syndrome and six cases of sudden death
would be expected to occur within six weeks of vaccination as
coincident background cases.
Just over nine million people in priority groups, such as pregnant
women and those with long-term illnesses, and another two million
front line health and social care workers will be offered the
vaccine in Britain over the next two months.
Decisions will be taken soon over whether to offer the vaccine
more widely.
The research also suggested that 397 per one million vaccinated
pregnant women would be predicted to have a spontaneous abortion
within one day of vaccination.
But this is the rate of spontaneous abortion that would occur
on any given day out of a group of one million pregnant women
during a vaccination campaign or not.
Dr Black wrote: “Misinterpretation of adverse health outcomes
that are only temporally related to vaccination will not only
threaten the success of the pandemic H1N1 influenza vaccine programme,
but also potentially hinder the development of newer vaccines.
"Therefore, careful interpretation of vaccine safety signals
is crucial to detect real reactions to vaccine and to ensure that
temporally related events not caused by vaccination do not unjustly
affect public opinion of the vaccine.
"Development and availability of data banks that can provide
locally relevant background rates of disease incidence are important
to aid assessment of vaccine safety concerns.”
The researchers said although scientists know that events connected
only be time does not prove cause and effect, the cases 'nonetheless
raise public concern'.
Prof David Spiegelhalter, Winton Professor of the Public Understanding
of Risk, University of Cambridge and Co-Director of Straight Statistics,
said: "What a fine paper. If millions of people are vaccinated
then just by chance we can expect bad things to happen to some
of them, whether it's a diagnosis of autism or a miscarriage.
"By being ready with the expected numbers of chance cases,
perhaps we can avoid overreaction to sad, but coincidental, events.
And why don't we ever see a headline 'Man wins lottery after flu
jab'?"
Professor Robert Dingwall, University of Nottingham, said: "The
difference between cause and coincidence is difficult enough for
specialists to grasp, let alone the wider public.
"However, this paper is very important in spelling out the
fact that just because two events happen at the same time, they
are not necessarily related. There is a background rate of death,
disease and accidents that happen all the time regardless of what
medical interventions are going on.
"Confusing cause and coincidence may lead to serious policy
mistakes that put people unnecessarily at risk.
"I am sure that some coincidences will emerge from a high-profile
vaccination campaign and we must be careful not to be misled by
them."
Meanwhile the World Health Organisation said that pregnant women
could be immunised with any of the vaccines licensed for use against
swine flu.
Dr Marie-Paule Keiny, from the WHO, said: “ Sage (the Strategic
Advisory Group of Experts) has concluded that the safety profiles
are good and recommend that pregnant women can be immunised with
any of the licensed vaccines.”
* A
full list of h1n1 vaccine ingredients, alerts and warnings.
Reference
Sources 172
November 1, 2009
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