Let me start this by saying that I am 100% in favor of vaccinations for all kids. I am also completely convinced that climate change is happening and is the biggest public health problem we will face in the next 50 years. And I take evolution as far and away the best explanation for differentiation and change in species.
I say these things first because I am about to argue that a certain amount of skepticism about the opinions of scientists and technologists is a very good thing, and that public policy based, in part, upon science but also based upon what is good for corporate interests should always be viewed with a healthy bit of cynicism. And that we, who want to use science to educate our policy making, should always apply a dose of humility to the conclusions about tomorrow that can be drawn from what we know today.
Having said that, let me now state some sympathy for the parents who fear that current vaccinations and current vaccination schedules might be dangerous to their kids. They are told, repeatedly, that the scientific consensus is that there is no proved relationship, and yet they are skeptical. And, while I disagree with the conclusions they have drawn, a certain amount of skepticism is completely warranted.
Skepticism in the past
Let me tell you about Gwen Molinar. She was a middle-aged woman living in the small town of Wilsonville, Illinois, in the 1970's. When a company decided to buy an abandoned coal mine in the community and turn it into a hazardous waste landfill, this made no sense to Gwen and her neighbors. Abandoned coal mines are notoriously “leaky.” How could liquid hazardous wastes be safely put into one? Besides, she saw, day in and day out, the lackadaisical behavior of the people employed at the site.
The scientists and technologists at the company, and at the Illinois Environmental Protection Agency and at the US Environmental Protection Agency all told the people of Wilsonville not to worry, that this was going to be a “state of the art” landfill, with the best technology available. “There was nothing to worry about,” she was told by the scientists and technologists. “We have completely studied this. We know best.”
Gwen and her friends fought the landfill, in the legislature and in permitting processes and in the press. But she was repeatedly told “don’t worry, we know best.” The landfill went in. And, sure enough, two months later it was leaking! Ultimately, a judge ordered the wastes to be removed, and down the road, the citizens of Wilsonville got a settlement from the corporate interests who wanted the landfill sited. To my knowledge, the never got an apology from the scientists and technologists who were so wrong.
In the early days of my career as a professional environmental advocate, I saw this dynamic happen repeatedly. Scientists for the tobacco companies and the asbestos companies told us that there was no evidence that their products caused cancer. Joanna Hoelscher, the environmental chair of the Illinois League of Women Voters, was scoffed at by the scientists when, in 1975, she testified at a Pollution Control Board hearing about the dangers of something called “acid rain.” Many years later, the US and other countries invested hundreds of millions of dollars in controlling this problem.
In 1976, there was a coordinated effort by scientists and technologists (mostly paid by chemical companies) to ridicule the notion that the earth’s ozone layer might be threatened by spray cans. Decades later, after the discovery of a hole in the ozone layer, those materials are now gone from the cans and from our air conditioners.
In 1978, environmentalists were accused of being doomsday predictors when we talked about “the greenhouse effect,” a name changed much later to “global climate change,” an issue where the science skeptics have changed sides.
Also in 1978, environmentalists cautioned US EPA from loosening its health protection standard for “photochemical oxidants” (smog), that the standard in place had a minuscule margin of safety. (I still have a copy somewhere of the testimony I gave at the hearings.) But the scientists and the technologists said that this was unsupported by the science at hand, and EPA raised the limits. Then, 20 years later, they lowered the limits below what it was in 1978, and today, the best available science is that it is still too high.
In the same year, when public health advocates warned about “second hand smoke,” we were told that we were over-reacting, that there was no good evidence linking side-stream smoke to health problems in non-smokers. Only two years later, US EPA issued the first of many reports on the extraordinary health impacts of second hand smoke. And the cultural attitudes towards smoking in the US have changed completely in the intervening decades.
When I was just starting as a professor, it was common knowledge that stomach ulcers were caused by too much acid in the gut, and that this was directly related to too much stress. When, in 1982, Marshall and Warren proposed that ulcers were, in fact, caused by a bacterium, they were condemned as quacks by “serious” doctors and scientists. They shared the Nobel Prize in Medicine for this discovery 23 years later.
In 1984, some people were worried about the possible serious side effects of the pertussis (whooping cough) vaccine. The scientists and most of the doctors said that this was a terrible over-reaction, and that vaccination rates had to be maintained in order to control this disease. Many years later, the same scientists were now promoting a “safer” DTP shot, quietly ignoring the inconsistency with their earlier position.
The pediatric profession, a group I have the utmost respect and admiration for, are frustrated by today’s “anti-vaxxers.” Don’t they understand that there are no scientific studies supporting a link between vaccines and autism? In all of the studies, no link has been found. Public health advocates and the media call the parents “irresponsible,” “ignoramuses,” “flat-earthers,” “selfish,” “loony,” “crazy,” etc.
But that same profession, back in the 1950's, offered the scientifically supported conclusion that autism was caused by “refrigerator moms,” the notion that some mothers, at a critical moment in their child’s development, turned their attention and affections away, causing the child to turn inward. My god, if it weren’t enough for the mother to cope with the difficulties of having an autistic child, to have the scientists blame her for the disease!
Humility is called for
How awkward, for pediatricians with some memory of their past mistakes, to be so horribly demeaning to the parents of autistic children today. Even worse, if they have no memory of this past. Some humility is clearly called for.
The best scientific studies that exist today have failed to find any relationship between vaccines and autism, and this has been the result of many studies. That is, I believe, a true statement. But it is usually presented in a slightly different syntax: “Science shows that there is no relationship between vaccines and autism.” That is not a true statement. Failing to find the relationship casts doubt on the existence of the relationship, but it is not conclusive evidence that the relationship does not exist. This is a common fallacy, where failure to find a positive association is offered as success in finding a negative relationship.
Or another statement that is dubious. “We have to rely upon science, which means scientific experiments. We can’t base policy on anecdote.”
As if anecdote were never a part of science. On the contrary, lived experience is the beginning of all science. Before the prospective epidemiological studies and the randomized clinical trials are done, someone has to have noticed something in their lived experience that allows them to get the grants to do the studies.
It is also true that, too often, people worry about things based upon another common fallacy, post hoc ergo propter hoc. “After this, therefore because of this.” If A follows B, then B caused A.” If my child develops autism after getting vaccinated, then the vaccination caused the autism.
We ought not ignore the many controlled studies that we have, repeatedly failing to find any association between vaccines and autism. But we ought not deride those whose lived experience suggests otherwise, particularly given the long history of careful science and technology lagging behind the anecdote. Calling the parents “crazy” and “loony” and “selfish” is uncalled for.
Then, on top of this, it is also true that many of the studies that we rely upon are financially supported by or conducted by those with a financial stake in their outcome. And there is plenty of evidence that private interests are quite capable of shaping governmental decisions. When the tobacco companies told us in the past not to worry about smoking, public health advocates scoffed. Ought we not apply some of the same cynicism to the influence of the pharmaceutical companies in this era?
In the face of this history of the limits of science and technology, and the potential for bias, isn’t a certain amount of science skepticism warranted? Not so much that we don’t vaccinate our kids, but enough to show some respect for parents struggling with this decision?
A respectful message
Here is how I think that would affect our message. First, we are committed to finding the causes of autism. If it isn’t vaccinations, then we need to know what it is. Second, we acknowledge the role of anecdote, lived experience, in the development of scientific understanding, and we acknowledge the experiences of the parents who have lived these experiences. And, third, we know we are not perfect, and that there are both heuristic and financial biases in the study of medical efficacy.
But, fourth, science is more than anecdote, and we have done many, many studies, and we keep finding no relationship. That doesn’t mean “we are right and you are wrong,” particularly given the financial biases at work. No study will ever say “your are absolutely wrong.” But we find nothing to support the argument that the parents are right. If their interpretation were accurate, we would expect to find some research evidence for their position, but we don’t. The best evidence we have is that the anecdotal information is outweighed by the clinical trials. At some point, we have to act to protect millions of kids, and as the problem of vaccination skepticism goes global, billions of kids.
Therefore, fifth, we will continue to be on the look-out for signs that we are wrong, because we can never know “for sure.” In the meantime, we have to resolve the uncertainty in favor of protecting hundreds of millions of children, worldwide. We will vaccinate aggressively, as this is absolutely proven to be successful in preventing death, disease and misery, and will continue to be one of the most important public health measures available.
And we will continue to be skeptical. Not so much to paralyze us in responding to overwhelming risks, such as global warming. Enough to “temper our assertions with doubt,” but also to temper our doubts with assertion.
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