Friday, 25 June 2010

To vaccinate or not - that is the question

On 24 May 2010, Dr. Andrew Wakefield, the surgeon at the centre of the MMR controversy was struck off the UK medical register by the General Medical Council (GMC) for serious professional misconduct after a two and a half year investigation.
To understand the controversy, one has to understand the story...
In a nutshell, Dr Wakefield & colleagues co-authored a paper that was published in 1998 in the esteemed Lancet, a highly respected, peer-reviewed medical journal. The paper was a write up into a study involving 12 children who were self-selected into his clinic due to gastric complications sometimes associated with autistic spectrum disorders. They were selected primarily due to parents' concerns over the link with the MMR triple vaccine reporting that symptoms had only begun following immunisation with the vaccine.
Wakefield's findings concluded that the associated gastric disease and symptoms of autistic spectrum disorder (developmental regression) in the group of children who were previously 'normal' was generally associated in time with 'possible environmental triggers'. These possible triggers were reported to be MMR in eight cases and measles infection in one.
Although no causal connection was proven in his study between the MMR vaccine and the symptoms, Wakefield called for a suspension of the triple vaccine combination until more research could be done. He also recommended that parents should opt for single jabs separated by at least a year.
The publication of the paper and the subsequent media coverage were linked to a steep decline in the vaccination rates in the UK and a sharp rise in confirmed cases of measles, with 2 child fatalities as well as others seriously ill on ventilators. What precipitated the crisis was a removal of the single vaccines altogether and therefore the removal of choice so that parents were left with an emotional and difficult decision as to take the unproven 'risks' allegedly associated with the MMR vaccine or the face the risk of their child contracting measles, mumps and/or rubella due to a lack of immunisation.
What further added to the debate was that Tony Blair, the prime minsiter at the time of the controversy famously refused to comment whether his child Leo was vaccinated with the MMR.
On 2 February 2010, the Lancet formally retracted Wakefield's 1998 paper with 10 of the 12 co-authors later publishing a retraction of the interpretation made in that paper.

About MMR

  1. The MMR is a live measles, mumps and rubella triple vaccine containing attenuated (less potent than the actual disease-causing) viruses.
  2. Two doses are required - one at pre-entry to primary school (around 13 months) and the second at around 3-5 years. The second dose is not a booster dose and is given to those who do not develop measles from the first dose.
  3. It is sold by Merck as MMRII and by GSK Biologicals as Priorix.
  4. Side Effects/Adverse Reactions (may occur from each component of the MMR) can include:
  • fever
  • malaise
  • rash
  • temporary joint pain
  • acute or chronic arthritis (in older women)
  • anaphylaxis (rare)
  • neurological disorders (eg. temporary paralysis of the legs)
  • aseptic meningitis (rare and not in the UK where the urabe mumps strain is not used in the MMR)
  • upper respiratory tract infections
  • irritability

Claims against Wakefield

  • data fixing
  • conflicts of interest (previously not declared)
  • unethical obtaining of biopsy samples (often without parents' consent)
  • paid to conduct the study by solicitors representing parents who believed their children had been harmed by MMR & failing to disclose this
The argument for MMR/ The safety of MMR
  • no study to date has been able to reproduce the results from Wakefield's 1998 study
  • numbers in his study were very small (12) to make any significant scientific conclusions
  • since 1998, the MMR vaccine could have been improved to limit the adverse effects and side effects of the previous formulations
  • historically, the introduction of mass vaccination programmes of governments across the world have benefitted from herd immunity resulting in the eradication of some of the most virulent and life-threatening global diseases. By and large, this is an example of a successful implementation programme
Defending the 1998 study (evidence, findings, interpretation)
  • increased incidence of autism in line with the introduction of the MMR though correlation has not yet been proved
  • decreased incidence of autism since a reduction in the uptake of MMR though correlation has not yet been proved
  • Wakefield was never against vaccination per se - just the MMR triple vaccine combination stating that the risk of interactions from 3 live viruses were increased and that more research into MMR was required whilst offering single jabs
  • the design and reporting of safety outcomes in MMR vaccine studies, both pre- and post-marketing is largely inadequate
  • increased incidence of measles thought to be linked to the reduced uptake of the MMR could easily be attributed to parents not being offered the single jab alternatives

The campaign against Wakefield was spear-headed by The Sunday Times journalist Brian Deer who in February 2009 published his 2 year 'investigation' and a front page spin-off story alleging that Wakefield "changed and misreported results in his research, creating the appearance of a possible link with autism..." amidst various other lurid charges. Deer claimed that his 'investigation' was confirmed by evidence presented to the GMC.

However, what the newspaper did NOT report was that the GMC investigation (into Wakefield) was triggered by a complaint from... Brian Deer who used information in his report arising from a disciplinary hearing which he himself instigated by making allegations himself to the GMC. This is extraordinary! It is very difficult to interpret this other than a witch-hunt.

Conclusions

The clinical jury is still out on the risks of MMR. The claims that MMR has been conclusively proved to be safe is based on epidemiological research which at best remains methodologically inadequate and worst has been misleadingly spun. However, to date there is overwhelming scientific evidence that there is no causal link between the MMR triple vaccine and autism; Wakefield's data has not been reproducible. There is no proven correlation with an increase in autism since the introduction of the MMR vaccine and there is no proven correlation with a decrease in autism since the Wakefield controversy led to a decrease in its uptake. However, there IS an increase in the incidence of measles since the fall in MMR vaccine uptake rates. We have lost herd immunity for this disease and measles is again endemic in the UK.

Far from being disproved, Wakefield's Lancet findings of a new clinical syndrome have been replicated and his concern that a small proportion of children may be at risk through the impact of a MMR vaccine on some kind of pre-existing vulnerability looks ever more plausible and clearly, more research is desperately needed.

This problem would never have arisen if single vaccines were made available, thus ensuring the safety of public health by providing choice and a contingency. More importantly, it would have reassured anxious parents and would have prevented unnecessary alarm, concern and fear. But of course, this is far too costly and inconvenient for the Government, not to mention the fact that they were not prepared to concede any ground over the multiple vaccine (single vaccines cost more than the triple vaccine and would require a longer implementation time given that vaccinations need to be administered at timely intervals). To be fair, the spacing of single vaccines in 3 separate doses does not reduce the chance of adverse effects and may leave children exposed to risk of infection by the 2 diseases not immunised against first.

However, the media attempt to hang Wakefield now that the evidence is clearer on MMR is utterly reprehensible, thoroughly dishonest and grossly unfair. Wakefield's Press Releases were always cautious, but some media outlets were unnecessarily alarmist and together with Government agencies treated the public like moronic masses (justified in some quarters admittedly but in principle, incredibly insulting). They did their part in perpetuating the myth that MMR is linked to autism and now they want a scapegoat.

If one really examines any research scientist and scrutinises the funding mechanism for important medical research with the level of determination, doggedness, detail and diligence as much as the case against Dr. Andrew Wakefield, one will invariably find some link to a drugs company, pharmaceutical giant or indeed a Government edict. It is highly probable that one can dig up suitable 'dirt' like this on anyone in this field of research if they delve deep enough. Understandably so given the reality of funding scientific research and its purpose and place within clinical medicine.

I would not want to be part of a culture that discourages scientists from reporting their findings and honest conclusions, or indeed whistle-blowing as the case may be especially if this relates to public health. They may be wrong, but they may just be right.

The story is not yet over.....

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