2 Background to the controversy
In February 1998, Andrew Wakefield and twelve co-authors published a study in The Lancet – a respected peer-reviewed medical journal. The paper was published with the highly technical, but seemingly innocuous, title: ‘Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children’. It was based on a study of twelve children who had been referred to Wakefield's clinic with gastrointestinal disease. Most of the children had a regressive form of autism in which they appeared to develop normally as infants, before losing acquired skills including communication.
In medical examinations the lining of the children's intestines all showed patchy inflammation. According to the authors, the findings seemed to support the hypothesis that a damaged intestine may, in some cases, trigger behavioural changes in children. The mechanism suggested for this in the Lancet paper relies on the ‘opioid excess’ hypothesis for autism. When peptides from food such as barley, rye and oats, and casein from dairy products, are not fully digested in the gut, they are absorbed and bind with peptidase enzymes. These enzymes usually break down the naturally occurring peptide opioids that function in the central nervous system. The hypothesis suggests that the consequential disruption of the central nervous system adversely influences brain development.
Wakefield's paper relates that the parents or the physicians of eight of the study's twelve children reported that behavioural problems started within two weeks of the MMR triple vaccine being administered. This evidence was purely anecdotal. In the discussion part of the paper, the authors acknowledge as much: ‘We did not prove an association between measles, mumps, and rubella vaccine and the syndrome described,’ and ‘Published evidence is inadequate to show whether there is a change in incidence or a link with measles, mumps, and rubella vaccine’ (Wakefield et al., 1998).
However, at a press conference to mark the publication of the paper, Wakefield told reporters that he believed that the three vaccines in MMR should be given separately. Investigative journalist Brian Deer (2004) recalls the occasion:
At the centre of the speakers’ table sat the principal author of the study, Dr Andrew Wakefield. Cutting a dashing and charismatic figure, the young gastroenterologist had a very different message to impart. Yes, it was just one study and yes, there was no proof, but he personally believed that action was needed. ‘One more case of this is too many,’ he declared. ‘It's a moral issue for me and I can't support the continued use of these three vaccines given in combination until this issue has been resolved.’ He wanted single jabs.
(Deer, Sunday Times, 22 February 2004)
Although the suggestion of a link between the MMR vaccine and autism was made at a press conference and was not explicitly part of the research paper, the study itself came under fire for its methodology and data interpretation. The question is often asked how such a contentious paper came to be published in the first place. Click on the following link to download a PDF of the original paper published in The Lancet (1998), 351, pp. 637–41 – Reading 1 in detail. The chapter id entitled ‘The Lancet Paper’ from MMR and Autism: What Parents Need to Know by Dr Michael Fitzpatrick, which outlines the response of the scientific community to the controversy. The author, a general practitioner and himself a father of an autistic son, is a vociferous proponent of the MMR vaccine. As you read, keep a note of the categories of arguments that Fitzpatrick employs in his critique – for example, scientific,(accessed 6 September 2012). It will be useful to have this paper to hand as you now look at
What strikes me as particularly significant from Fitzpatrick's account is that the circumstances surrounding the Lancet paper's publication highlighted the subjectivity of the process of deciding not only what scientific research gets done, but also which results get published and why. It is often said in science that ‘the facts speak for themselves’. The circumstances of research approval, publication and reaction to scientific investigations which have political, economic and social consequences seem to me to exemplify what a fallacy this is. The reading also highlights how complex the process is of testing a seemingly straightforward hypothesis in the ‘real world’ as opposed to carefully controlled laboratory conditions.
Fitzpatrick chronicles the barrage of experts stepping forward to criticise Wakefield's study and issue reassurances about the safety of MMR. In spite of this, the effects were dramatic. The Health Protection Agency monitors vaccination uptake in the UK: from a peak of 92% uptake in 1995–96, this figure dropped to below 80% by 2003 and was as low as 60% in some areas. There was a concomitant rise in cases of measles. In 2003, 442 cases of measles were reported: a threefold increase in the numbers reported in 1996. It was clear that a significant number of parents had decided not to immunise their children with the MMR vaccine.