Measles, Vaccines and Autism
The current controversy over whether
parents should be forced to have their children vaccinated for measles is one
of the painful signs of our times. Measles was virtually wiped out in the
United States, years ago. Why the resurgence of this disease now?
The short answer is that false
claims, based on other false claims, led many parents to stop getting their
children vaccinated against measles.
The key false claim was that the
vaccine for measles caused an increase in autism. This claim was made in 1998
by a doctor writing in a distinguished British medical journal, so it is
understandable that many parents took it seriously, and did not want to run the
risk of having their child become autistic.
Fortunately, others took the claim
seriously in a very different sense. They did massive studies involving half a
million children in Denmark and two million children in Sweden. These studies
showed that there was no higher incidence of autism among children who had been
vaccinated than among children who had not been vaccinated.
Incidentally, the
"evidence" on which the original claim that vaccines caused autism
was based was just 12 children. But the campaign to convince the public was a
masterpiece of propaganda.
The story line was that
pharmaceutical companies who produced the vaccine were callously risking and
sacrificing helpless children in pursuit of profit. This is the kind of
dramatic stuff the media love. It never seemed to occur to the media that
lawyers who were suing pharmaceutical companies had a vested interest in this
story line that the media fed on to the public.
Unfortunately, it takes time to run
careful scientific studies, involving vast numbers of children in different
countries. That allowed the propaganda against vaccines to go on for years.
Eventually, however, the results of the studies so completely discredited the
claim that the measles vaccine caused autism that the medical journal which had
published the article publicly repudiated it. The doctor who wrote the article
had his license revoked.
By this time, however, there was a
whole anti-vaccine movement, and crusading movements are seldom stopped by
facts.
This was not the only false claim
involved. What made that claim seem plausible was a highly publicized increase
in the number of children diagnosed as being autistic or being "on the
autism spectrum."
What was not so widely publicized
was that the definition of "autism" had expanded over the years to
include children who would never have been called autistic by the standards set
up when autism was defined by its discoverer, Professor Leo Kanner of the Johns
Hopkins medical school, back in 1943.
Professor Kanner fought against the
expansion of the definition of autism but, after his death, the definition
continued to expand -- and the number of children who met the expanded
definition greatly increased.
There were financial incentives for
this expansion. Late-talking children, for example, could get government
programs to pay for their treatment if they were designated as autistic or on
the autism spectrum.
Despite headlines and hysteria about
skyrocketing numbers of children diagnosed as autistic, the number of children
who meet the original definition of autism has been relatively stable in recent
years, at about one quarter of one percent of all children, according to
Professor Stephen Camarata of the Vanderbilt University Medical Center, in his
recent book, "Late-Talking Children."
It may be significant that the
number of children regarded as mentally retarded has fallen by numbers similar
to the rise in the number of children regarded as autistic. According to
Professor Camarata, "This too suggests that changes in definitions and in diagnostic
practices are contributing to the perceived 'epidemic' of autism."
Does this mean that vaccines are
safe? In a categorical sense, nothing on the face of the earth is 100 percent
safe -- including going unvaccinated. But the claim that vaccines cause autism
has been discredited by evidence.
Some say the decision to vaccinate
or not should be the parents' choice. That would be fine if their child would
live isolated from other children. But that is impossible.
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