http://www.bmj.com/cgi/content/full/323/7317/838
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Primary care
Ethical debate
Vaccination
against mumps, measles, and rubella: is there a case for deepening the debate?
How
safe is MMR vaccine?
Validity
of the evidence
Dealing
with uncertainty
GP's
response
Vaccination against mumps, measles, and rubella: is there a case for
deepening the debate?
How safe is MMR vaccine?
Tom Heller
School of Health and Social Welfare at the
Open University, Milton Keynes, MK7 6AA
My duties as a general practitioner include immunising babies and small
children against a range of common diseases. Recently, I have been
increasingly uncomfortable when giving the combined mumps, measles,
and rubella (MMR) vaccine. I find myself wondering if I would submit
my own children for this immunisation if they were currently at that
age.
I find it difficult to be certain that the vaccine is as safe as the
authorities say that it is. Somehow, the more strident the experts
become, the less believable I seem to find them. The Department of
Health website (http://193.32.28.83/mmrvac.htm)
gives many references and internet links to the published studies that
support its views, but it gives only one reference that raises the
issue of a link between MMR vaccine and potential adverse reactions.
The partial use of evidence that is apparent within official pronouncements
is echoed by other experts. For example, Elliman and Bedford focus
on possible problems with the research methods of people concerned
about possible adverse effects of the MMR vaccine.1 They
do not mention potential problems with the research that concludes
that the vaccines are safe. In addition, what are we to make of
these and other researchers2 who
declare funding from drug manufacturers involved in manufacturing
vaccines?
Listening
to people and parents
The NHS Plan emphasises the need to give people in receipt of treatment and
services a greater part in the decisions that affect them and the
NHS in general.3
However, for some reason, the choices seem restricted when it comes
to discussing MMR vaccine. But parents remain anxious. Those with
autistic children have become sensitised to the possibility that the
condition may have been caused by an intervention such as
vaccination.4
Other parents are convinced of the link between the MMR vaccine and their
child's subsequent development of autism and have formed support
groups and lobbying organisations. In the United Kingdom the main
organisation is JABS (Justice, Awareness, and Basic Support, www.jabs.org.uk). When does a series of
individual observations from families with affected children count
as evidence if each one is dismissed as an isolated incident?
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Professional issues
In the United Kingdom, general practitioners receive a fee for each child
immunised and other payments are triggered for meeting targets.
Missing these targets would have serious consequences for the
financial stability of the practice, and there is considerable pressure
on members of the team to ensure that children are immunised with
every recommended vaccine.
I am not alone in my concern, and possible confusion, about administering
the MMR vaccine. A recent survey of health workers in north Wales
sought to elicit the knowledge, attitudes, and practices relating to
MMR vaccine, particularly the second dose.5
Only 45% of the professionals (54% of the general practitioners) agreed
completely with the policy of giving the second dose of the MMR
vaccine. These professional concerns do not seem to have greatly
affected the numbers of children receiving the vaccine, and national
MMR coverage has only fallen from 91% in 1994-5 to 88% in
1998-9, although in some districts the uptake is below 75%.6
It is not easy to question authority these days.7
Andrew Wakefield, the author of some of the studies that have questioned the
development and subsequent use of MMR vaccine, has been subjected to
personal as well as professional abuse (www.autism-spectrum.com/vaccine.htm).
Perhaps keeping my head down and not even talking about these issues
would be the easiest option.
Footnotes
Competing interests: None declared.
References
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1. |
Elliman D, Bedford H. MMR vaccine: the continuing saga. BMJ
2001; 322: 183-184 |
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2. |
Kaye J, Melero-Montes M, Jick H. Mumps, measles, and
rubella vaccine and the incidence of autism recorded by general
practitioners: a time trend analysis. BMJ 2001; 322: 460-463 |
|
3. |
Department of Health. The NHS Plan. London:
Stationery Office, 2000. (CM 4818-I.) |
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4. |
Goldberg D. MMR, autism, and Adam. BMJ 2000; 320:
389 |
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5. |
Petrovic M, Roberts R, Ramsay M. Second dose of measles,
mumps and rubella vaccine: questionnaire survey of health professionals. BMJ
2001; 322: 82-85 |
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6. |
Public Health Laboratory Service facts and figures. www.phls.co.uk/facts/vaccination/cover.htm
(accessed 18 Sep 2001). |
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7. |
Hunt G, ed. Whistleblowing in the health service.
London: Edward Arnold, 1995. |
Validity of the evidence
Dick Heller
Evidence for Population Health Unit, School
of Epidemiology and Health Sciences, Medical School, University of Manchester,
Manchester M13 9PT
The basic question is, "what is the real evidence about the dangers of
MMR vaccine?" The evidence for a link between MMR vaccine and
the development of autism is based on a hypothesis derived from an
observation that the parents of eight out of 12 children investigated
for gastrointestinal symptoms and autism associated the onset of
autism with the MMR vaccine.1
There has been no evidence to support the hypothesis.
Several studies have been reported as negating the hypothesis, although
there are doubts about each of these. Some of the studies are
ecological in design; they examine trends in the development of
autism with the trends in use of MMR vaccine. Recently reported studies
2 3 show
that the rise in reported autism over the past decade or so bears no
relation to any changes in rates of MMR vaccination, and this is
consistent with other data showing no epidemiological evidence for a
causal association. 4
5
Most people who have reviewed the evidence have rejected the notion that
MMR might be associated with autism.6-8 A
recent review from the US Institute of Medicine concludes that
"the evidence favours rejection of a causal relationship."9
Listening
to people and parents
Unfortunately, patients are often not precise at identifying the cause of
their illness, and personal anecdote can do no more than suggest a
hypothesis that needs formal scientific testing: "Hypotheses
can become `facts' long before the critical data are in."10
The concern in the community comes from the difficulty in
understanding and expressing evidence. All we have at the moment is
a hypothesis based on anecdote, without supporting evidence. Any
evidence that does exist, however weak it might be perceived to be,
fails to support the hypothesis.
Comparing
risk of autism with risk of vaccine preventable diseases
It is difficult to measure, express, and understand risk. The prevalence of
autistic spectrum disorders is 91/100 000 children.11
If as many as 15% of these children had autism as a result of the
MMR vaccine, 7326 children would have to be vaccinated to "produce"
one child with autism. How many cases of mumps, measles, or rubella
would the lack of vaccination of this number of children produce?
What would their complication rates be? Unfortunately, we have not
established good intelligence systems to explore the public health
effects of changes in immunisation.12 We
do know that for measles alone, death rates are 1-2 per
1000 infected people in the United States and that 1 in
1000 will get encephalitis (and some of these will have
permanent brain damage).13 If
most children who were not vaccinated developed measles, the
complication rates suggest that discontinuing vaccination would do
considerable harm and that this harm would far outweigh any possible
benefit from possibly reducing the incidence of autism.
These common communicable diseases cannot be eliminated if the levels of
immunisation in the community fall below a critical value. It is a
legitimate concern of those with responsibility for public health to
seek to maintain high vaccination rates.
In summary, I feel that there is no evidence that MMR vaccine causes autism
and considerable evidence to say that it does not. I believe that
the dangers of reducing vaccination on the basis of an
unsubstantiated hypothesis are considerable.
Footnotes
Competing interests: None declared.
References
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1. |
Wakefield A, Murch S, Anthony A, Linnell J, Casson D,
Malik M, et al. Ileal-lymphoid nodular hyperplasia, non-specific colitis, and
pervasive developmental disorder in children. Lancet 1998; 351:
1327-1328 |
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2. |
Kaye J, Melero-Montes M, Jick H. Mumps, measles, and
rubella vaccine and the incidence of autism recorded by general
practitioners: a time trend analysis. BMJ 2001; 322: 460-463 |
|
3. |
Dales L, Hammer SJ, Smith NJ. Time trends in autism and in
MMR immunisation coverage in California. JAMA 2001; 285: 1183-1185 |
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4. |
Taylor B, Miller E, Farrington C, Petropoulos M-C,
Favot-Mayaud I, Li J, et al. Autism and measles, mumps, and rubella vaccine:
no epidemiological evidence for a causal association. Lancet 1999;
353: 2026-2029 |
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5. |
Patja A, Davidkin I, Kurki T, Kallio MJ, Valle M, Peltola
H. Serious adverse events after measles-mumps-rubella vaccination during a
fourteen year prospective follow-up. Pediatr Infect Dis J 2000; 19:
1127-1134 |
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6. |
Nicoll A, Elliman D, Ross E. MMR vaccination and autism. BMJ
1998; 316: 715-716 |
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7. |
Wise J. Finnish study confirms safety of MMR vaccine. BMJ
2001; 322: 130 |
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8. |
Roberts R. MMR vaccination and autism. BMJ 1998;
316: 1824 |
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9. |
Institute of Medicine. Immunisation safety review:
measles-mumps-rubella vaccine and autism. http://books.nap.edu/books/0309074479/html/index.html
(accessed 5 Sep 2001). |
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10. |
Gellin BG, Schaffner W. The risk of vaccination |
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11. |
Roberts R. MMR vaccination and autism. BMJ 1998;
316: 1824 |
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12. |
Heller RC, Page J. A population perspective to
evidence based medicine |
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13. |
Watson JC, Hadler SC, Dykewicz CA, Reef S, Phillips L.
Measles, mumps, and rubella |
Dealing with uncertainty
Stephen Pattison
Department of Religious and Theological
Studies, Cardiff University, Cardiff CF10 3EU
Some moral theorists would say that Tom Heller is just having an emotional
reaction, but I would say that this kind of discomfort is part of
moral judgment.1
He applies one of the best known tests for assaying the rightness or
wrongness of acts called the golden rule,2
expressing this as, "would I submit my own children for this
immunisation if they were currently at that age?" He also
discusses the voice of authority that says it is safe to administer
MMR vaccine and how his doubts are amplified in inverse proportion
to the experts' certainty. The question is, then, how might his
colleagues and members of the public be helped to live with reality
and limits of knowledge without necessarily abandoning useful public
health practices that may be in their long term interests?
Although the scientists may be deemed to be working on one paradigm of
rationality and correlative enlightenment, ordinary people,
including doctors, have a more complex view of reality. This kind of
composite knowledge is often seen, from a rational point of view, as
superstition and irrationality which needs to be dispelled and destroyed.
You cannot discount another's knowledge even if you may doubt its scientific
value. Making a decision to have a child immunised is a moral
dilemma for parents and this must be respected. Not acknowledging
others' moral dilemmas does not make them go away. There is a crisis
of expert authority and trust in scientific judgment surrounding MMR
vaccine and a crisis of mutual respect. A decision needs to be made
about what kind of evidence counts and how this is weighed and
related to lay views of reality. In doing so, scientists must take
care not to treat fear and reservation as ignorance and then try to
destroy it with a blunt "rational" instrument.
I wonder if people know that general practitioners are given financial incentives
to deliver a certain proportion of vaccinations. This again raises
the issue of whether doctors are acting in the best interests of the
individuals or whether they are dancing to a financial tune. We need
to ask whose interests do and should clinicians serve
do
they focus on individuals, or is their job to deliver centrally
determined, scientifically informed, health policy?
Risk and power are unequally distributed in this situation. The government
determines the risk management strategy to deal with the diseases
mumps, measles, and rubella. However, it is individual clinicians
and parents who have to implement this strategy and may have to live
with its consequences. The MMR vaccine issue focuses many of our
concerns about ethical and responsive public health in the clinical
context in a helpful way. We are trying to work out what
individually respectful and sensitive, publicly accountable,
evidence based clinical practice might look like.
Footnotes
Competing interests: None declared.
References
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1. |
Oakley J. Morality and the emotions. London:
Routledge, 1992. |
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2. |
Singer P, ed. A companion to ethics. Oxford:
Blackwell, 1991. |
GP's response
Tom Heller
I feel as though I have been through a process which is rather similar to
the explorations that many parents go through at the time of taking
important vaccine related decisions on behalf of their children. My
search for understanding will have to continue. Of course, I respect
that the full weight of the most powerful authority figures in modern
medicine have concluded that MMR vaccine is safe (box), but
lingering doubts remain for me and for many others.
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Groups that have
endorsed safety record of MMR vaccine1
Committee on Safety of Medicines Committee on Safety of Medicines and Medicines Control Agency Joint
Committee on Vaccination and Immunisation Working group of the Medical Research Council Public Health Laboratory Service Communicable Disease Surveillance Centre Royal College of Paediatrics and Child Health World Health Organization |
My final thoughts are summed up in the following quotation:
"Informed refusal must remain an acceptable choice in a free democracy,
and the culture of informed consent, with both religious and
philosophical exemption, must be maintained. The difficult balancing
act will be in determining the right of the state to control an
infectious disease and the right of the individual to chose."2
References
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1. |
Committee on Safety of Medicines. MMR vaccine: the facts. Current
Problems in Pharmacovigilance 2001; 27: 3 |
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2. |
Poland G, Jacobson R. Vaccine safety: injecting a dose of
common sense. Mayo Clinic Proceedings 2000; 75: 135-139 |
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ALL
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AS PROVIDING MEDICAL OR LEGAL ADVICE. THE DECISION WHETHER OR NOT TO
VACCINATE IS AN IMPORTANT AND COMPLEX ISSUE AND SHOULD BE MADE BY YOU, AND YOU
ALONE, IN CONSULTATION WITH YOUR HEALTH CARE PROVIDER.