Wakefield Attributes Autism Development to the MMR Vaccine
In a paper published in The Lancet in 1998, Andrew Wakefield et al suggest the MMR (measles, mumps, and rubella) is causing autism in children. Despite several scientific faults and conflict of interest, Wakefield’s paper is largely accredited with kick starting the global anti-vaccination movement. An article titled The MMR vaccine and autism: Sensation, refutation, retraction, and fraud by T. S. Sathyanarayana Rao and Chittaranjan Andrade on the NCBI database discusses the faults of the 1998 Wakefield paper that has since been retracted.
Sample Size and Characteristics
This article first mentions how the Wakefield study only included a sample size of 12. This is a very small sample size for a medical study and is not sufficient to test whether a vaccine is causative of a developmental disorder. In addition, Rao and Andrade mention that “a temporal link between the two [MMR vaccine and autism development] is almost predestined” as both events take place in very early childhood. It is almost like testing whether entering the 7th grade induces puberty; both events take place around the same time but are certainly not causative of one another. Perhaps Wakefield could have stengthened his study if he had not only had a much larger sample size, but also included older individuals who had recently received the MMR vaccine and/or had not received the vaccine but still developed autism. Shockingly, Rao and Andrade reveal that Wakefield falsely reported his method of sampling. After investigation, Wakefield’s study was found to have used selective sampling to obtain its cohort. This means that Wakefield and his colleagues picked subjects on their own, discriminating as they saw fit. This is already a no-no in medical study, worsened by the fact that Wakefield lied about it.
Financial Motives and Further Misconduct
At this point, readers may ask themselves “Why would Wakefield risk his scientific credibility to attack vaccines?”. This is also something that Rao and Andrade discuss in their article. It turns out that Wakefield was funded by lawyers who were engaged in lawsuits against vaccine-producing companies. This was not revealed to The Lancet before publication. Furthermore, Wakefield and colleagues were found guilty of improper “invasive investigations” on the children subjects as they had not obtained the necessary clearance to do so, according to Rao and Andrade. Finally, Wakefield even blatantly lied about the diagnosies of many subjects, quite loosely and freely using the word “colitis” despite non-abnormal findings.
Implications
Vaccination with the MMR vaccine has declined since the publication of Wakefield’s paper in 1998, according to a PBS article titled The Autism-Vaccine Myth. More and more people are refusing to vaccinate their children, which puts both individuals who are too young to be vaccinated and the immunocompromised at risk. The goal of vaccination is to create herd immunity with the ultimate result of eradicating human-resivoir diseases. If most people are immune to a disease, then that disease will have a very difficult time spreading and replicated in multiple hosts. When people do not vaccinate their children, they are increasing the number of susceptible hosts a disease has and thus increasing the chance the disease will infect others. This is especially unfair to the too-young-to-be-vaccinated and the immunocompromised. Vaccination involves injecting a weakened form of a disease in order to mount an immune response and the consequent production of antibodies against that disease. While not 100% effective, vaccines are highly effective and generally result in lifetime immunity to a disease. However, because vaccines require a functioning immune system, they sometimes cannot be given to immunocompromised individuals as well as the very young (infants do not have a fully functioning immune system). Thus, these are the very groups that would have the most severe complications to a disease like measles, which generally is not. Unfortunately, vaccination rates have greatly declined since the 1998 publication of Wakefield’s paper, despite its retraction and the overwhelming evidence of fraud against it. According to the above mentioned PBS article, measles vaccination rates fell to only 80% in 2003-2004 in the UK, with similar trends in other previously high vaccination rate countries. While 80% may seem high to those not familiar with epidemiology, according to an article in Stanford Medicine, a 5% drop in MMR vaccination among children would cause a tripling in the number of measles cases for that group.
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