MMR vaccine and autism


Claims of a link between the measles, mumps, and rubella vaccine and autism have been extensively investigated and have been found to be false. The link was first suggested in the early 1990s and came to public notice largely as a result of the 1998 Lancet MMR autism fraud, characterised as "perhaps the most damaging medical hoax of the last 100 years". The fraudulent research paper, authored by Andrew Wakefield and published in The Lancet, falsely claimed the vaccine was linked to colitis and autism spectrum disorders. The paper was retracted in 2010 but is still cited by anti-vaccine activists.
The claims in the paper were widely reported, leading to a sharp drop in vaccination rates in the UK and Ireland. Promotion of the claimed link, which continues in anti-vaccination propaganda despite being refuted, has led to an increase in the incidence of measles and mumps, resulting in deaths and serious permanent injuries. Following the initial claims in 1998, multiple large epidemiological studies were undertaken. Reviews of the evidence by the Centers for Disease Control and Prevention, the American Academy of Pediatrics, the Institute of Medicine of the US National Academy of Sciences, the UK National Health Service, and the Cochrane Library all found no link between the MMR vaccine and autism. Physicians, medical journals, and editors have described Wakefield's actions as fraudulent and tied them to epidemics and deaths.
An investigation by journalist Brian Deer found that Wakefield, the author of the original research paper linking the vaccine to autism, had multiple undeclared conflicts of interest, had manipulated evidence, and had broken other ethical codes. The Lancet paper was partially retracted in 2004 and fully retracted in 2010, when Lancets editor-in-chief Richard Horton described it as "utterly false" and said that the journal had been deceived. Wakefield was found guilty by the General Medical Council of serious professional misconduct in May 2010 and was struck off the Medical Register, meaning he could no longer practise as a physician in the UK. In January 2011, Deer published a series of reports in the British Medical Journal, which in a signed editorial stated of the journalist, "It has taken the diligent scepticism of one man, standing outside medicine and science, to show that the paper was in fact an elaborate fraud." The scientific consensus is that there is no link between the MMR vaccine and autism and that the vaccine's benefits greatly outweigh its potential risks.

Background

Revaccination campaign

In the wake of the measles outbreaks, which occurred in England in 1992, and on the basis of analyses of seroepidemiological data combined with mathematical modeling, British Health authorities predicted a major resurgence of measles in school-age children. Two strategies were then examined: either to target vaccination at all children without a history of prior measles vaccination or to immunize all children irrespective of vaccination history. In November 1994, the latter option was chosen and a national measles and rubella vaccination campaign, described as "one of the most ambitious vaccination initiatives that Britain has undertaken" was commenced: within one month, 92% of the 7.1 million schoolchildren in England aged 5–16 years received measles and rubella vaccine.

MMR litigation starts

In April 1994, Richard Barr, a solicitor, succeeded in winning legal aid for the pursuit of a class action lawsuit against the manufacturers of MMR vaccines under the UK Consumer Protection Act 1987. The class action case was aimed at Aventis Pasteur, SmithKline Beecham, and Merck, manufacturers respectively of Immravax, Pluserix-MMR and MMR II. This suit, based on a claim that MMR is a defective product and should not have been used, was the first big class action lawsuit funded by the Legal Aid Board after its formation in 1988. Noticing two publications from Andrew Wakefield that explored the role of measles virus in Crohn's disease and inflammatory bowel disease, Barr contacted Wakefield for his expertise. According to Wakefield supporters, the two men first met on 6 January 1996. The Legal Services Commission halted proceedings in September 2003, citing a high probability of failure based on the medical evidence, bringing an end to the first case of research funding by the LSC.

1998 ''The Lancet'' paper

Wakefield's paper "Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children" was published in The Lancet on 28 February 1998. An investigation by journalist Brian Deer found that Wakefield had multiple undeclared conflicts of interest, had manipulated evidence, and had broken other ethical codes. Based on Deer's findings, Peter N. Steinmetz summarizes six fabrications and falsifications in the paper itself and in Wakefield's response in the areas of findings of non-specific colitis; behavioral symptoms; findings of regressive autism; ethics consent statement; conflict of interest statement; and methods of patient referral. The Lancet paper was partially retracted in 2004 and fully retracted in 2010, when The Lancets editor-in-chief Richard Horton described it as "utterly false" and said that the journal had been deceived. Wakefield was found guilty of serious professional misconduct by the General Medical Council in May 2010 and was struck off the Medical Register, barring him from practicing medicine in the UK. In 2011, Deer provided further information on Wakefield's improper research practices to the British Medical Journal, which in a signed editorial described the original paper as fraudulent.
The scientific consensus is that there is no link between the MMR vaccine and autism and that the vaccine's benefits greatly outweigh its risks. However, by the time that scientists had shown the narrative to be false, it had become part of the lay understanding of autism. The narrative was easy to understand and apparently consistent with anecdotal evidence of children receiving autism diagnoses shortly after having been vaccinated.
By the time it was retracted, all authors other than Wakefield had requested their names be removed from the publication.
Fiona Godlee, editor of The BMJ, said in January 2011:

Media role

Observers have criticized the involvement of mass media in the controversy, what is known as 'science by press conference', alleging that the media provided Wakefield's study with more credibility than it deserved. A March 2007 paper in BMC Public Health by Shona Hilton, Mark Petticrew, and Kate Hunt postulated that media reports on Wakefield's study had "created the misleading impression that the evidence for the link with autism was as substantial as the evidence against" through an attempt to create "balanced reporting". Earlier papers in Communication in Medicine and British Medical Journal concluded that media reports provided a misleading picture of the level of support for Wakefield's hypothesis.
A 2007 editorial in Australian Doctor complained that some journalists had continued to defend Wakefield's study even after The Lancet had published the retraction by 10 of the study's 12 original authors, but noted that it was an investigative journalist, Brian Deer, who had played a leading role in exposing weaknesses in the study. PRWeek noted that after Wakefield was removed from the general medical register for misconduct in May 2010, 62% of respondents to a poll regarding the MMR controversy stated they did not feel that the media conducted responsible reporting on health issues.
A New England Journal of Medicine article examining the history of anti-vaccine activists said that opposition to vaccines has existed since the 19th century, but "now the antivaccinationists' media of choice are typically television and the Internet, including its social media outlets, which are used to sway public opinion and distract attention from scientific evidence". The editorial characterized anti-vaccine activists as people who "tend toward complete mistrust of government and manufacturers, conspiratorial thinking, denialism, low cognitive complexity in thinking patterns, reasoning flaws, and a habit of substituting emotional anecdotes for data", including people who range from those "unable to understand and incorporate concepts of risk and probability into science-grounded decision making" and those "who use deliberate mistruths, intimidation, falsified data, and threats of violence".
In a January 2011 editorial in The American Spectator, Robert M. Goldberg contended that evidence from the scientific community of issues with Wakefield's research "were undermined because the media allowed Wakefield and his followers to discredit the findings just by saying so".
Seth Mnookin, author of The Panic Virus, also partly blames the media for presenting a false balance between scientific evidence and people's personal experiences: "Reporting fell into this 'on the one hand, on the other hand' fallacy, this notion that if you have two sides that are disagreeing, that means that you should present both of them with equal weight."
Concerns have also been raised over the journal peer review system, which largely relies on trust among researchers, and the role of journalists reporting on scientific theories that they "are hardly in a position to question and comprehend". Neil Cameron, a historian who specializes in the history of science, writing for the Montreal Gazette, labeled the controversy a "failure of journalism" that resulted in unnecessary deaths, saying that: 1) The Lancet should not have published a study based on "statistically meaningless results" from only 12 cases; 2) the anti-vaccination crusade was continued by the satirical Private Eye magazine; and 3) a grapevine of worried parents and "nincompoop" celebrities fueled the widespread fears. The Gazette also reported that: