Vaccinations

Due to the current outbreaks of measles, I thought it pertinant to address the science of vaccinations.

First discovered in 1796 by Edward Jenner, Vaccinations have led to the erradication of some of the worst diseases such as Smallpox, and are on the way to placing even more in the history books. Jenner found that milkmaids who had suffered with Cowpox, were not suceptible to Smallpox. He inoculated a boy with the Cowpox virus, let him recover, then exposed him to Smallpox. Amazingly the boy did not develop Smallpox symptoms at all! This was the first vaccine. Since then vaccinations have evolved massively, and now offer no risk to patients, despite widespread myths.

One of the major cases leading to the Anti-vaccine movement was when Andrew Wakefield et al. published a document claiming that the MMR vaccination causes Autism. The paper, published first in The Lancet on the 28th February 1998, used a case study of 8 children, out of 12 studied, who all showed symptoms of Autism within 1 month of receiving the MMR vaccine. The connection claimed was that the vaccine caused intestinal inflammation which allowed the diffusion of normally non digested protein molecules from the intestines into the bloodstream. Wakefield inferred that these travelled to the brain where the affected development and caused autism. The 8 children all had this intestinal inflammation.
There were several issues with the study they conducted. The first being that there was no control variable, this meant that there was no way of scientifically establishing whether a link, between the MMR vaccine and Autism, was a cause and effect relationship or a coincidence. The probability that it was a coincidence is quite high, as in 1998, 1 in 2000 children were diagnosed with Autism. This meant that statistically the number of children developing autism after have the vaccine was 25 children per month. Therefore the exclusion of a control group shows that the results could be purely coincidental.
Other issues within the study and its conclusions include; a lack of complete or systematic data collected from the children, meaning the data cannot be fully represented. Giving young infants unnecessary invasive testing which the team did not have the correct permissions to conduct, making the study ethically unsound. The publication bias that occurred when choosing which children’s data to include in the published study was the largest proof of data mishandling. The study tested more than 12 children, as explained by Brian Deer in the British Medical Journal’s published analysis of the case.
“When I broke the news to the father of child 11, at first he did not believe me. “Wakefield told us my son was the 13th child they saw,” he said, gazing for the first time at the now infamous research paper which linked a purported new syndrome with the measles, mumps, and rubella (MMR) vaccine. “There’s only 12 in this.””
The statement from the parent shows that Wakefield had chosen which children to include in order to present the view of the data that he needed. This is an unarguable case of bias showing the negative effect the mishandling causes, both in public opinion and the vaccine crisis it stimulated. “Immunization rates in Britain dropped from 92 percent to 73 percent, and were as low as 50 percent in some parts of London”.
Public opinions led to this crisis of anti-vaccination, and even now years later, public opinion still regards the case as infamous.