WASHINGTON, June 28 (UPI) -- Where are the unvaccinated homeschooled children with autism? Nowhere to be found, says a doctor who treats autistic children and is knowledgeable about the homeschooled world.
"It's largely nonexistent," Dr. Jeff Bradstreet told UPI's Age of Autism. "It's an extremely rare event."
Bradstreet treats autistic children at his medical practice in Palm Bay, Fla. He has a son whose autism he attributes to a vaccine reaction at 15 months. His daughter has been homeschooled, he describes himself as a "Christian family physician," and he knows many of the leaders in the homeschool movement.
"There was this whole subculture of folks who went into homeschooling so they would never have to vaccinate their kids," he said. "There's this whole cadre who were never vaccinated for religious reasons."
In that subset, he said, "unless they were massively exposed to mercury through lots of amalgams (mercury dental fillings in the mother) and/or big-time fish eating, I've not had a single case."
Bradstreet said his views do not constitute a persuasive argument that low vaccination rates are associated with low rates of autism, but it is worth studying.
"That's not yet science," he said. "It doesn't rise to the level of a powerful observation. It's a place to say, OK, well that's interesting, what does that tell us?"
About 2 million children are being homeschooled in the United States. The number of those unvaccinated is unclear, but judging by the school opt-out rates in some parts of the country where there is more concern about vaccinations, it could be 3 percent or more. For example, in Oregon's Lane County roughly 2,000 students out of a total of 51,000 have exemptions, about 4 percent.
Applying that ratio to the U.S. homeschooled population would equal 80,000 children. At the current autism rate of one in 166 children, several hundred would be expected to have autism.
Bradstreet said he has tried to persuade epidemiologists to study that subset of the homeschooled population, but they expressed doubts the results would apply to broader groups.
"I said I know I can tap into this community and find you large numbers of unvaccinated homeschooled, and we can do simple prevalence and incidence studies in them, and my gut reaction is that you're going to see no autism in this group."
He said every researcher he contacted refused to investigate, "because it would not have any power to change people's opinion -- you could never apply it to the next population." He said critics could assert that homeschoolers are a unique group and that parents might choose to homeschool a child "because they knew he was different," although neither would explain the lower autism prevalence.
He also said he thinks homeschoolers would be a better population to examine than a genetically and culturally isolated community such as the Amish.
"The purists would say that's too odd of a group," Bradstreet said, and added that he agrees. "You can't draw conclusions from that kind of population."
His comments referred to the series of reports in The Age of Autism on an apparent low prevalence of the condition among the Amish, most of whom are unvaccinated.
Monday, this column reported that a top official of the U.S. Department of Health and Human Services told parents he will consider whether to launch a study of autism rates among the Amish or other unvaccinated populations. Such a study apparently has never been done.
Bradstreet said he thinks that no matter what unvaccinated population researchers study, "it would be a rare event" to find autism. His views fall into the distinct minority among scientists and medical experts, who say a link between vaccines and autism has been discredited. A panel of the prestigious Institute of Medicine -- part of the National Academy of Sciences -- said last year that research should now go to "promising" areas.
The vaccine theory centers on the hypothesis that a mercury-based preservative called thimerosal, used in an increasing number of childhood vaccinations in the 1990s, triggered a huge spike in diagnoses.
Bradstreet's linking of autism to mercury in fish and maternal dental fillings is also rejected by mainstream medical experts. The comments do, however, echo one aspect of UPI's reporting on the Amish.
A doctor in Virginia said he was treating six unvaccinated Amish children, four of whom had high levels of mercury in their bodies that he thinks triggered their autism. He suspects the exposure came from coal-fired power plants, which emit mercury as a byproduct.
Bradstreet said he realizes his views on vaccines, and his own son's autism, expose him to charges he is seeing what he wishes to see, but he argues that government researchers harbor a bigger conflict of interest because the government mandates vaccinations and vouches for their safety.
"The problem for them is even more than the problem for us," he said. "Many of us who are concerned about vaccines and the role they're playing in the immune system and autism are traditionally trained physicians who vaccinated our kids and are only reluctantly being forced, when it was thrown in our face, to say there's got to be something wrong with vaccines if it did this to my kid.
"So in that situation, even though we would be accused of being more biased, we are probably more objective because we were believers."
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