Friday, June 12, 2009

Autism

Do not expect to arrive at certainty in every subject which you pursue. There are a hundred things wherein we mortals. . . must be content with probability, where our best light and reasoning will reach no farther. — Isacc Watts, English poet, theologian, hymn writer.


The February 21, 2009 issue of Newsweek had an article about the big autism "controversy." Perhaps you know someone who has an autistic child. If so, you may be aware of the grassroots movement that is trying to prove to us that autism is caused by childhood vaccines. These folks are convinced that a preservative in vaccines, called thimerosal, "has been implicated in autism" (Google "autism" and you will get over 18 million hits; you will get just under a million hits for "thimerosal").

There are three reasons for keeping this non-issue alive.
  1. Parents who are convinced that thimerosal made their child autistic.
  2. Lawyers who are bringing class action suits against pharmaceutical companies.
  3. Physicians who have joined the anti-vaccine parade.
When you read the plaintive cry of pain from parents of autistic children, you can understand their emotional discomfort and readiness to accept any idea that can help explain their plight. Unfortunately, most of these parents are absolutely certain they have an autistic child because they agreed to have the child vaccinated against childhood disease. Explanations for what goes wrong in this world can be soothing even if the explanations are bogus.

It is sad to notice how certain these parents are in their assumptions of the relationship between vaccinations and autism. Their certainty does not allow them to accept the possibility they could be wrong. This degree of certainty can be dangerous. It is dangerous because vaccinations have saved the lives of millions of children on this planet. They do not accept the fact that without vaccinations we would unnecessarily be missing millions of children because they would have died unnecessary deaths.

Certainty is understandable — it is the curse of being alive. The demand for certainty is natural to humans. This is where we need to be thoughtful. Insisting on certainty may be folly because life is based on probabilities not guarantees. Granted some probabilities are extremely high while others are unbelievably low. One of the important lessons science has taught us is that we need to withhold judgment on what we don't know until good evidence has been found. As Jacob Bronowski reminded us, "knowledge is an unending adventure at the edge of uncertainty."

The problem is that few people can sort out good evidence from bad evidence. Doing so is not a matter of willpower or an intensity of feelings. For millennia, people have found many avenues for poor evidence: personal experience, authority figures, majority opinion, strong beliefs. These types of evidence are highly error prone. Since the time of Galileo, we have found that information separated from our personal biases and desires is much more reliable. The venue for finding this type of information is called the scientific method.

Science is poorly understood by the public. Good sources of evidence demand patience, objectivity, intelligence (because science is hard to do), and skepticism. Skepticism is the difficult stance that one takes by being willing to be proven wrong. Good scientists are never certain because they know that all knowledge is tentative and subject to change. This is what is so difficult for non-scientists to understand. They often think that scientific findings are eternal and unchangeable. Just the opposite is true.

Using the legal to discover the truth of a claim constitutes the vast hole in the idea that vaccines cause autism. By using the legal system to "prove" their case, anti-vaccination supporters are bypassing the highest standards of knowledge given to us by science. This is why the court system has become so skittish about "junk science." To illustrate this, you only need to look at the evidence put forth by the pro-thimerosal advocates. One example is the website entitled The great thimerosal cover-up. The end of the article has a section in which twenty-two expert opinions are quoted supporting the dangers of thimerosal. At first glance, this would seem highly credible and convincing to many of us.

However, of the experts listed, only six had advanced degrees: two with a Ph.D. and four with an M.D. One of these experts was quoted six times. All of these quotes were taken from books rather than peer-reviewed journals. Peer-reviewed journals that emphasize empirical knowledge are the gold standard for finding what is true and what is not. These journals are important because submitted articles are read by the top experts in the particular field who try to find what is wrong with the article. The tougher the critics, the more credence can be given to scientific articles.

Much of the world languished for a thousand years in the Middle Ages because the major source of evidence was power and authority. Not until Galileo dared defy the authorities did the ability to see more clearly begin to take shape. Since then we have learned more about humans and the world around us than all of the millennia prior to his bravery and courage. The tools of science have rid us of devastating diseases, put a person on the moon, invented radio, TV, computers and the smart phone and given us cognitive behavior therapy. The use of power and authority could have lasted forever and these discovers would have never taken place without the tools of science.

In the web site referred to above, the rest of the citations came from popular magazines and books such as Alternative Medicine and Building Wellness. These sources are not not known to utilize the highest standards for honest and helpful information gathering. One of the experts has since taken himself outside the self-correcting arena of science. Russell Blaylock is a retired neurosurgeon whose bio states, "During his 26 years of treating patients in his medical, nutritional, and neurosurgery practice, he became disgusted with the state of medicine in the U.S. and recently retired to devote his full attention to nutritional studies and research."

This bit of information about Dr. Blaylock makes him sound like a pioneer who is not afraid of bucking the medical establishment so that he alone can find the real truth about autism. In reality, the time of the renegade genius is long past and is now the stuff of fictional movies and novels. The science of medicine has become too complicated for any lone wolf researcher to independently overturn the combined work of tens of thousands of competent scientists.

What do the hundreds of scientists who specialize in this area have to say? Although the original link between autism was seen as a possibility in the 1990s and early 2000s, recent medical opinion has begun to change as more and new evidence has become available (remember — this is how science works).
  • 2003: The medical journal, Pediatrics, published an article titled, "Safety of Thimerosal-Containing Vaccines: A Two-Phased Study of Computerized Health Maintenance Organization Databases." this study found no consistent significant associations between vaccines with thimerosal and "neurodevelopmental outcomes."
  • 2004: An organization known by the lengthy name of The Immunization Safety Review Committee at the Institute of Medicine published a report that examined scientific studies from around the world. This review found no convincing evidence that vaccines cause autism.
  • 2004: One of the premier medical journals in the world, Lancet, published an article concluding that thimerosal based vaccines are "not associated with an increased risk of pervasive developmental disorders."
  • 2007: Another prominent medical journal, the New England Journal of Medicine, published a study that did not support the notion that thimerosal caused autism.
  • 2008: The medical journal, Archives of General Psychiatry, put another take on the research. They noted that, because of the public outcry about thimerosal, drug companies have stopped using it as a vaccine additive. Nevertheless, the frequency of autism keeps increasing "at a steady rate."
These articles in the peer-reviews journals above are only a fraction of the evidence that vaccines are not responsible for autism. The trend is now well established. The matter should be settled except for the certainty of the anti-vaccine crowd. As these folks continue their quixotic campaign they are verifying Voltaire when he said, "Doubt is uncomfortable, certainty is ridiculous."

As a side note, it was discovered in 2004 that the doctor who began this thimerosal scare, Dr. Andrew Wakefield of England, had a severe conflict of interest. He was paid over half a million dollars for helping lawyers try to prove the case against thimerosal. This vast amount of money certainly brings Dr. Wakefield's integrity into question regarding his stance against thimerosal.

We all know that we humans scare easily. What is more difficult is the task of getting us to calm down after the scare has taken place. Emotions can easily override intelligence. Yet, it is our reason that can save us as a race, not our emotions running rampantly out of control.

The big tragedy in keeping kids from getting vaccinated is that they might well die from measles or other deadly childhood diseases. In England a large number of parents, a few years ago, stopped having their children vaccinated with the MMR vaccine. Consequently, England now has more children developing measles than at any other time in the last twenty years. This is unfortunate because medical science has had the opportunity to almost eradicate measles in children.

For the first time in history, fewer children all over the world are dying from disease. In the 1980s only twenty percent of children were vaccinated against deadly illness. Today, eighty percent of children in the world have been saved from death by having been vaccinated. We know that childhood immunizations have saved the lives of about nine million children. Vaccinating young children around the world has shown a seventy-four percent drop in children who used to die from measles.

Because media stars such as Oprah have supported the anti-vaccination program, public attention has been drawn away from finding the real causes of autism. Millions of dollars have been wasted in futile legal wrangling that could have been used for more research to help families with autistic children. Fighting the power of science because of inadequate information and public hysteria is wasted effort because the human race needs all the intellectual resources available to make this planet a better place to live.

For more information on the actual science of vaccines, see...

Science Based Medicine
Timeline of the Autism Scare

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