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MMR: Will we ever be sure it's safe?
With
the medical establishment bitterly divided over the triple vaccine's link
to autism, we can only be certain of one thing: we still don't know enough
about it. Health Editor Sarah-Kate Templeton investigates
When Dr Andrew Wakefield was approached by
parents claiming their children developed autism after receiving the MMR
vaccine he was sceptical. When the vaccine was introduced in 1988 it was
hailed as the key to eradicating the three childhood diseases measles,
mumps and rubella in this country. The suggestion that such an important
government policy could actually be damaging to the public was a shocking
prospect and one Andrew Wakefield and his colleagues considered unlikely.
But
the numbers of parents attending the consultant gastroenterologist's clinic
at the Royal Free Hospital in London, presenting similar accounts of how their
child regressed and developed bowel problems, persuaded Wakefield to
investigate.
Wakefield's
research showed that these children suffered from a new type of bowel
disease, which might cause autism, and which, he suggested, could be
triggered by the MMR vaccine. The work was published in the prestigious
Lancet medical journal, peer reviewed by respected scientists, and a press
conference was arranged to discuss the highly controversial and worrying
findings.
The
atmosphere of the press conference was tense. The Department of Health
announced that the Chief Medical Officer had called for a meeting with the
researchers. And, as Wakefield approached the platform to discuss his
findings, senior members of the medical school to which he belonged
insisted that it was 'absolutely essential' that confidence in the MMR
vaccine was not damaged.
But
what Wakefield said at this meeting was to damage confidence in the vaccine
for years to come. By announcing his belief that the vaccines should be
given out at one-year intervals he sparked a call for the measles, mumps
and rubella vaccine to be offered in single doses, a call which is now
being debated by an Expert Group set up by the Scottish Executive and
reportedly considered by Prime Minister Tony Blair.
The
suggestion that the MMR vaccine was unsafe infuriated the medical
establishment and divided the profession. Nowhere was the row more bitter
than in the corridors of the Royal Free Hospital in London. While Wakefield
and his team pursued their research into the theory that the MMR vaccine
caused autism and bowel disease in children his colleague and most
outspoken critic, Professor Brent Taylor, consultant paediatrician at the
same hospital, embarked on a series of studies which insist the
controversial vaccine is safe.
Last
week each of the two camps published further evidence to back up their
views. A paper by Wakefield and Professor John O'Leary, molecular
pathologist at Coombe Women's Hospital in Dublin, provided fresh evidence
linking the measles virus to autism and bowel inflammation. The study, to
appear in the journal Molecular Pathology, but published early online,
showed that genetic testing detected the presence of the measles virus in
75 out of 91 children with both bowel disease and autism. Traces of the
virus were found in only five out of 70 controls of healthy children.
Days
later, a paper by Taylor, published in the British Medical Journal,
attempted, again to demolish Wakefield's theory. Taylor and colleagues
studied children born before and after the introduction of the MMR and
concluded that there was no evidence the jab caused autism or bowel
problems. They looked at the medical records of 473 autistic children born
between 1979 and 1998 so that they could compare youngsters born before and
after the introduction of the MMR, in 1988. They found no change in the
proportion of children with bowel disorders and regression across the
20-year period.
Taylor
declared his paper must draw a line under the debate. He said: 'This must
be close to the endgame for the belief, which has not been based on proper
science, that MMR is the cause of autism or a sub-group of autism.'
But
at the same time, Wakefield promised that his scientific work would
continue. He said: 'The body of evidence that we are accumulating is based
on rigorous peer-reviewed science, and it keeps coming. We are just warming
to this task, we have five further papers coming out. Step by step, piece
by piece the jigsaw is taking shape and a picture is beginning to emerge.
'We
believe, we trust, in the parents' story, and our trust in the parents'
story has been vindicated in paper after paper. Not in this sort of
quasi-epidemiological study that looks retrospectively at records but
actually looking at patients and the tissues from those patients and those
have endorsed the parents' concerns thus far.'
But
as papers compete to either prove or demolish the alleged link between the
MMR, autism and bowel disease the public debate has moved away from the
scientific evidence to finding a practical solution to ending the decline
in immunisation rates and preventing further measles outbreaks. At the same
time the government is coming under intense pressure to give parents a
choice about the vaccines their children receive.
The
Conservative Party has called for single vaccines to be made available in
addition to the MMR as a pragmatic step to increase the level of
immunisation and increasing numbers of medical experts are arguing that
this is now the only sensible way forward.
Tricia
Murphy-Black, professor of midwifery at Stirling University, has studied
much of the literature on the MMR vaccine and is convinced it is safe. She
does, however, believe that single vaccines should be made available for
the children of parents who are not.
She
said: 'I do not think the government can reassure parents. It is not going
to be done by the Chief Medical Officer or Alan Milburn standing up and
saying 'this vaccine is safe'.
'I
think the government should back off and, very quietly, allow single
vaccines. The risk is that more people will refuse, the percentage of
vaccinated children will fall and there will be an increased risk of
measles outbreak.'
Last
year the Department of Health launched a £3 million advertising campaign to
persuade parents of the safety of the combined jab shortly after a paper
published in the journal Adverse Drug Reaction argued that the MMR was not
adequately tested. But falling immunisation rates suggest parents are not
listening to government reassurances. The image of John Gummer making
similar promises on BSE as he fed his daughter hamburgers in front of a
barrage of photo graphers has remained with us.
Some
clumsy attempts at spin to persuade parents to have their child immunised
with the MMR have backfired. Parents were infuriated when they received an
information leaflet on the vaccine from one health board which accused
parents who refuse the MMR for their child of behaving like drink-drivers.
Their confidence in the information provided by Greater Glasgow Health
Board was further eroded when they discovered that it was compiled by
vaccine manufacturer, Aventis Pasteur. Their doubts were further fuelled by
Tony Blair's refusal to say whether his son Leo was given the MMR.
Dr
John Sinclair, consultant urological surgeon at the Southern General
Hospital in Glasgow, and a concerned grandfather, insists doctors and
parents are antagonised by this approach.
He
said: 'As a doctor with a grandson due the MMR vaccine and a family history
of autistic spectrum disorders I am determined that he will receive single
vaccines.
'I
think a lot of us feel that there are too many senior doctors throwing
their weight around. They do not like being challenged.'
As
demand for single vaccines increases, private clinics are opening across the
country to give choice to parents who can afford to pay. In Health
Secretary Alan Milburn's constituency the Direct Health clinic is so
oversubscribed that it is laying on extra sessions to cope with the demand.
And Dr Peter Copp, who has administered thousands of single vaccines at his
private Edinburgh clinic, GP Plus, is planning to open another surgery in
Glasgow.
Dr
Peter Fletcher, a senior medical officer for the Department of Health in
the early 1980s, and author of a paper arguing that the licensing of the
MMR was premature, believes the government will now be obliged to offer
single vaccines in addition to the combined jab.
'I
think in the end they are going to have to give the single vaccine in
parallel with the MMR. I don't see how they are going to get out of that.
My personal view has always been that we should make single vaccines
available.
'I
have always thought, right from the beginning, we are in a free country and
it would be right for ordinary people to have the choice. It seems to me
that the single vaccines should never have been withdrawn. They were
withdrawn for purely financial reasons.'
The
Expert Group on MMR set up by the Scottish Executive is due to report its
findings within the next month. Part of its remit is to 'describe the
consequences of pursuing an alternative vaccination policy to MMR,' and is
widely expected to make a recommendation on whether single vaccines should
be made available.
While
some campaigners insisted they had little faith in the Expert Group because
the majority of those who sit on it are known to be supporters of the MMR
one member believes they may be forced to recommend single vaccines as a
purely practical measure.
The
expert, who did not wish to be named as all members have been warned
against speaking to the media, said: 'The question now is whether we can
maintain the level of coverage. The issue has to be one of public safety
and getting a higher level of protection against measles.
'If
there are at risk groups, the Expert Group has got to consider what the
options should be. These vaccines are available privately and there is a
question of 'should there be more availability?'
'There
is growing concern about vaccination rates and children dying from measles.
There has been a lot of discussion about whether the MMR should be the only
option especially when there is a two-tier system with the single vaccines
available to those who can afford it. This raises an ethical question.'
As
the debate shifts from the scientific evidence to the practical moves
necessary to push up vaccination rates and meet the demands of increasing
numbers of parents Andrew Wakefield is taking his research to America.
After years of tension, Wakefield said he was eventually forced out of his
post as an academic at the Royal Free Medical School because the results of
his work were unpopular. But, as the heat moves away from the Royal Free,
parents are determined to continue Wakefield's work by ensuring single
vaccines are reintroduced in this country.
David
Thrower, who believes his son's autism is a result of receiving the triple
vaccine, said: 'There are people on the Labour back benches who think there
is a problem. We see a rallying round of the authorities but the public is
confused and unconvinced.
'The
number of children affected is growing rapidly. I think the huge numbers of
autistic children are going to force a change on this issue.'
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