academic environmental studies   macalester college

Environmental Studies

Losing faith in science: the rhetoric of denialism in the autism/vaccines debate

Introduction

Background

Controversy

Present day

Conclusion
References & Links


   Comments & questions to:
   guytona@gmail.com


Losing faith in science: the rhetoric of denialism in the autism/vaccines debate

History of the MMR vaccine

Childhood vaccinations have long been a part of American and European history.  Starting with the widespread use of Edward Jenner's smallpox vaccine in 1796, and continuing with vaccines for polio, typhoid, tetanus, and other such diseases, common medical knowledge dictates that inoculating children as early as possible leads to a lower infant mortality rate (IMR), increased life expectancy, and better general well-being.  And it has worked.  Smallpox was completely eradicated in 1977, polio will cease to exist outside carefully-controlled laboratories in the very near future, and measles is likely next on the list, judging from its rapidly declining rate of infection following the 1963 introduction of its first vaccine.

Over time, medical experts have found ways to combine some individual vaccines into one single injection, both reducing the amount of time and pain necessary for the vaccine's administration, but also making such vaccines far easier to distribute, transport, and use in less developed areas of the world.  Without this breakthrough in vaccine consolidation, worldwide storage, production, and administration costs could be any number of times greater than what they are today. 

One such example is the measles, mumps, and rubella vaccine, better known by the acronym "MMR".  First introduced in 1971, the MMR vaccine is exactly what it claims to be: a single-shot vaccine containing a mixture of three live attenuated viruses.  However, a small number of patients do not develop measles immunity after receiving the first dose, so a second is routinely administered to ensure the vaccine's total efficacy.

The net medical effects of the MMR vaccine cannot be understated.  "The health and resource benefits due to vaccination against measles during the first 20 years of vaccine licensure," according to a 1985 study in Pediatrics, "have been enormous.  In this period [in the United States] it is estimated that vaccination against measles has prevented 52 million cases, 5,200 deaths, and 17,400 cases of mental retardation, achieving a net savings of $5.1 billion."  Worldwide, though there are not any widely-accepted statistics on the subject, the vaccine has likely produced the same effect.  Measles, once as common of a disease as chicken pox is today, is now almost nonexistent among developed populations, and mumps and rubella are not far behind.  A decreased incidence in mumps infections has likely maintained the male fertility rate among populations with significant exposure to the vaccine, as one of the disease's main side effects among males past the age of puberty is a specific condition that, in some cases, causes sterility.  Rubella, or German measles, was long known to increase the chances of congenital fetal defects if contracted by pregnant women, so its inclusion in this widespread vaccination has likely reduced the number of infants born with congenital birth defects. 

In short, the introduction of the MMR vaccine has improved the lives of countless people across the globe.  As all three diseases are highly contagious, a widespread reduction in incidence across all populations means an exponentially smaller risk of infection.

"Discovery" of vaccine/autism link

In 1998, Dr. Andrew Wakefield, a British surgeon and medical researcher, was the lead author on a study linking the MMR vaccine to a heightened risk of autism in the vaccine’s recipients.  The study focused on twelve children with chronic intestinal disorders, all with a history of normal mental development, who, after receiving MMR vaccines, suddenly began to show signs of mental regression and who were eventually diagnosed with autism spectrum disorders (ASD).  In this study, Dr. Wakefield theorized that the MMR vaccine somehow caused the intestinal infections, which subsequently spread to the brain and caused the onset of autistic behaviors.  To guard against this, he proposed that a set of three vaccines be administered instead, one each for measles, mumps, and rubella.  If administered at different times, the three diseases would not have a chance to interact, thereby eliminating the chance that they would cause the autism-inducing intestinal infections.

However, several key pieces of information did not come to light until years after the study had been published.  In 1997, one year prior to the study’s publication, Dr. Wakefield had filed for a patent on a stand-alone measles vaccine, one he asserted would avoid the problems of the existing MMR vaccine.  This patent, if granted, could have made him immense sums of money following the significant public response to his autism link study.  In addition, a 2007 hearing with the General Medical Council produced evidence that Wakefield had been paid to conduct the autism study by representatives of parents who thought MMR vaccines were inducing autism in their children, had performed spinal taps, colonoscopies, and other invasive procedures on his research subjects without proper approval or official medical reasons to do so, and had even purchased blood samples from children attending his son’s birthday party.  And, finally, an investigation by The Sunday Times later resulted in a published story claiming that Wakefield “changed and misreported results in his research, creating the appearance of a possible link with autism”.

But news soon spread of this apparent discovery.  As this information came from an ostensibly trustworthy source, parents and caregivers all across Britain started avoiding vaccines in droves.  According to an article in Psychiatric Times, the inoculation rate for the MMR vaccine fell from 92% in 1998 to below 80% following publication, while the number of measles cases in the UK jumped from 56 in 1998 to 1348 in 2008, including two confirmed deaths.  To the group of Britons (and later, Americans) who saw this as a reason to stop immunizing their children, the centuries-strong global history of successful vaccinations meant nothing in the face of one lone journal article.

Interestingly, one country has fully embraced an anti-MMR platform.  In 1988, Japan began phasing out all MMR vaccinations, reducing usage to zero by 1993.  While it is unclear exactly why Japan chose to take this course of action (considering that Dr. Wakefield's famous claim became public in 1998, a full decade later), they have since replaced the MMR vaccine with separate vaccinations for each disease.  In a study published in a 2005 issue of the Journal of Child Psychology and Psychiatry, three researchers examined the incidence rates of ASD in one section of the city of Yokohama.  Their findings indicated that for children with birth years of 1988 onward, the incidence of ASD "increased significantly", with an even more dramatic increase found in children with birth years of 1993 or later.  So, according to these data, not only did the elimination of the MMR vaccine not result in less childhood ASD, but the patterns of how much ASD increased seem directly proportional to the rate at which Japan phased out the vaccine.  In other words, switching from the MMR vaccine to three separate immunizations might actually increase the chances of contracting ASD, if this study is taken to be accurate.  Granted, correlation does not necessarily signify causation, but in this case, the correlation goes against everything anti-vaccine activists seem to believe.



"Fear Needle", by Rubén Díaz Alonso


Last updated:  5/3/2010

 


Macalester College · 1600 Grand Avenue, St. Paul, MN 55105  USA · 651-696-6000
Comments and questions to guytona@gmail.com