Sunday, April 17, 2011

Why the Debate Continues...

 The Autism-Vaccine Debate: Why It Won't Go Away
David Kirby-Author/Journalist
 
I have been speaking to young parents in my neighborhood of Park Slope, Brooklyn lately about vaccines and autism, which science and the media have once again pronounced as completely debunked for what I believe is now the sixth or seventh time.
These are highly educated, affluent and politically progressive people -- doctors, lawyers, entrepreneurs, writers and other successful professionals. And like half of the American population in one poll, many of my neighbors (though certainly not all) say that there is, or may be, an association between autism and the current U.S. vaccine schedule.
Although some Park Slope parents refuse to vaccinate their children at all - an unwise and dangerous choice in my opinion -- the vast majority makes sure their kids get immunized; although many do so on a schedule worked out with their pediatrician.
In general, it is the most highly educated parents who are now eschewing the CDC schedule and vaccinating their children at a different pace. In one recent presentation of data, for example, mothers with masters degrees were significantly more likely to forego the Hepatitis B vaccine birth dose than mothers with an 8th grade education.

Why do so many educated, successful parents still believe that the current vaccine schedule can hurt a small percentage of susceptible kids, and that some of those injuries might result in an autism spectrum disorder (ASD)? Despite all of the population studies showing no link, high-profile court cases that went against parents, insistence of omniscience by health officials and the public mauling of Andrew Wakefield, I don't think that many people around here have changed their minds.
That's because evidence of a vaccine-autism link did not come to them via a 12-year-old study published in a British medical journal, nor from Hollywood celebrities: Not very many had heard of Wakefield until recently.
Some of these parents actually keep up with the science, including a new review of autism studies in the Journal of Immunotoxicology which concludes: "Documented causes of autism include genetic mutations and/or deletions, viral infections, and encephalitis following vaccination."
Some of their evidence also comes from life -- from friends, family and business associates whose children had an adverse vaccine reaction, got sick, stopped talking and never recovered.
It's a fact that many children with ASD regressed following normal development just as they were receiving multiple vaccines at regular doctor visits. Health officials say the timing is entirely coincidental.

Regression usually occurs between 12 and 24 months, though one study found that some children show signs of autism as early as six months, but never before that age.
By six months of age, most U.S. children have received about 18 inoculations containing 24 vaccines against nine diseases. Over the next two years or so, they will receive another nine shots containing 14 vaccines against 12 diseases.
So whether a child regresses at six months, or 18 months, the tragedy happens during a period of intensive vaccination. In many cases, parents report that the child had an abnormal reaction after being vaccinated (seizures, spiking-fevers, diarrhea, lethargy, high-pitched screaming and/or other symptoms).
The temporal association might be coincidental, but for many autism parents, now tens of thousands in number (but certainly not all parents), there is nothing to dissuade them: they are certain that vaccines harmed their kids. I have spoken with thousands of them personally. Their stories of regression are hauntingly similar, describing a childhood catastrophe that was virtually unheard of when I was growing up.
These parents, and grandparents, naturally share their stories with brothers, sisters, friends, coworkers and the media, and before long half the population is questioning authorities who insist that there is zero chance of any association whatsoever.
Every year, thousands of new parents go through the same ordeal, which is why belief in a link is probably going up, not down. Sadly, this will continue for years to come as more and more parents join the ranks of the devastated but convinced. There is nothing that anyone can do or say -- not you, not me, not any scientist on earth -- until definitive proof of all the true causes of autism is found. But that appears to be years, or decades away.
Parents who say the vaccine-autism link has not been debunked are, like me, hardly "anti-vaccine." Why on earth would anyone not want to protect children from dangerous diseases? That is the epithet hurled upon most of them anyway. And it's what people will say about me as well, even though, as I said, I think parents should vaccinate their kids.
What's curious is the selective use of the "anti-vaccine" accusation. Few people call Dr. Bernadine Healy, former head of the NIH, "anti-vaccine" for not ruling out a possible link, and calling for the study of the children who actually got sick.
I have never heard it used against Temple Grandin, who said there should be "a closer evaluation" of vaccines and autism and echoed Dr. Healy by adding that, "These children should be carefully studied to determine when and why they lost language, and if factors such as vaccines and genetic predisposition may be causes."
And I've never heard it used against the many Somali parents of children with autism living in Minneapolis who said they are convinced that vaccines played a role, and will be telling that to CDC and NIH researchers who are trying to find out why the rate among Somali children is reportedly about 1-in-28 in that city.
Most parents in Park Slope are pro-vaccine, which is why they vaccinate their kids. They know the answer to the question, "Could vaccines be involved in some autism cases?" is not "Stop vaccinating all children now."
Instead, like me, they believe that more children today are more susceptible to vaccine injury and other environmental triggers, thanks to toxins such as heavy metals, air pollution, pesticides and a universe of endocrine disruptors unleashed into the environment. Other risk factors might be at play, such as vitamin D deficiency, parental age, closely-spaced births, caesarian births or even the stress of everyday life.
Such factors, both pre- and post-natal, might harm mitochondria, damage DNA and potentially result in immune and autoimmune disorders. These problems could then, in turn, increase the risk in some genetically susceptible children for early life problems like complex febrile seizures, myelin damage, and what has been called "mitochondrial meltdown." All three have been identified in medical journals and/or the U.S. federal Vaccine Court as plausible triggers of regressive autism. And all three can occur with, or without, vaccines.
They should be studied more, in my opinion.
The answer is not to stop vaccinating -- that would lead to widespread disease and suffering. The answer is to find out which children might be particularly susceptible to which vaccines, vaccine combinations or vaccine ingredients, and devise a schedule that is individually tuned to their specific conditions. This will build parental trust and strengthen, not weaken, the national vaccine program.
Even the CDC states:
Although some may call it a "one size fits all" approach, the recommended vaccine schedule is flexible, and it does account for instances when a child should not receive a recommended vaccine or when a recommended vaccine should be delayed. Those decisions, however, are best made in consultation with the child's doctor, and parents shouldn't be reluctant to have such discussions.
Until science can tell parents which children are most genetically vulnerable to neuroimmune injuries, more people around the country will probably "go Park Slope," if you will, and devise their own selection of vaccines at their own chosen schedule.
One hopes they proceed with great caution. For example, spreading out vaccines within the same series might confer less immunity, though we don't know because this has not been thoroughly studied.
Some parents might also skip the triple live-virus MMR vaccine altogether, because the manufacturer refuses to offer separate measels, mumps and rubella shots. Offering this simple choice alone might boost immunization rates by a couple of percentage points, so why not do it?
I have never agreed with the "anti-vaccine" movement, whose size and influence has been somewhat overblown by the media. Vaccination rates remain high. A recent wave of whooping cough in California occurred largely among vaccinated individuals. In fact, unvaccinated adults may have played a role: Only 1-in-10 adults in San Diego are believed to have received a pertussis booster shot, for example. Nobody is calling the other 90 percent dangerous "anti-vaxers," even if they may have helped create an outbreak that killed several children.

Why So Much Autism?
There is clearly no single cause of autism, and we are not going to find answers looking only at genes, or for that matter, only at thimerosal or MMR. But there remain many reasons why some parents, doctors, scientists and people with autism say a vaccine connection cannot be ruled out, at least in some cases.
My motive has never been to "blame vaccines." I have no personal reason whatsoever to oppose them, and little to gain -- believe me. What I have been trying to do is find out why so many more kids today are so sick.
I do not belive that better diagnosis and wider awareness can explain away a tidal wave of suffering. Such dinosaur mentality never helped a single child, and most credible scientists are abandoning it.
"It's time to start looking for the environmental culprits responsible for the remarkable increase in the rate of autism in California," Dr. Irva Hertz-Picciotto, an epidemiology professor at the University of California, Davis MIND Institute, has said. Those culprits, she said, might lie "in the microbial world and in the chemical world."
Another good example is Francis S. Collins, M.D., Ph.D, current Director of the NIH. "Recent increases in chronic diseases (like) autism cannot be due to major shifts in the human gene pool. They must be due to changes in the environment" and other factors, he told Congress in 2006. Collins called for more research into "environmental toxins, dietary intake and physical activity," in order to "determine an individual's biological response to those influences."
Dr. Thomas Insel, Director of the National Institute of Mental Health and Chair of the Interagency Autism Coordinating Committee, concurred with his boss, Dr. Collins, when he told me, "There is no question that there has got to be an environmental component here," because "this is not something that can be explained away by methodology, by diagnosis."
In my opinion, many children with autism are toxic. Some thing or things happened to make them sick. Unfortunately, our world has become a hazardous juggernaut through which increasingly fewer infants seem to emerge unscathed. We need to identify what is blocking their way, and fix it.
I know that many people will say the vaccine issue has been thoroughly investigated and debunked. I honestly wish that were the case, but it simply is not true. All of the "vaccine-autism" studies you hear about investigated just one childhood vaccine out of 14 (MMR), or one vaccine ingredient out of dozens (thimerosal). That is like announcing that air pollution does not cause lung cancer because you looked at carbon monoxide, alone, and hydrogen sulfide, alone, and found no link.
Moreover, many of the large epidemiological studies that purport to show no association between MMR or thimerosal and autism were conducted by people with vested interests -- financial or professional -- in defending vaccines and vaccine programs. Much worse than that, the vast majority of these studies were marked by methodological flaws that limit their usefulness and legitimacy. A thorough point-by-point rebuttal of the epidemiology will soon be published by the advocacy group SafeMinds.
What we do know is that reported autism rates began to explode right around the 1987-88 birth cohorts in the United States and a few other western countries, according to an EPA study.
"The greatest increase in ASD prevalence occurred in cohorts born between 1987 and 1992 across the United States," the EPA study concluded. Rates did not begin to increase in developing countries until a number of years later.
U.S. special education data found the exact same thing: ASD among students nearly tripled between the 1988 cohort (5-per-10,000) and the 1990 cohort (14.3-per-10,000) and then tripled again by the 1992 cohort (42.1-per-10,000). After that, the rate of increase slowed down significantly. Some of this increase is clearly due to an expansion of the ASD definition, but not all of it.

That should give scientists a lot to work with. If we believe the head of the NIH, then autism might be the result of "environmental toxins" interacting with individual genes. If we believe EPA scientists and Department of Education data, ASD rates boomed between the 1988 and 1992 birth cohorts, and increased at a much slower pace after that.
It seems reasonable to suspect, then, that average U.S. exposures to the environmental toxin(s) in question increased around 1988 (though they certainly were introduced before that) and continued to rise rapidly until at least 1992, when they began to level off. These exposures would have to have increased in developing countries several years later.
That seems like it would narrow the list down considerably. Because there is no one cause of autism, we need to look at all possible exposures and other environmental factors that might have increased dramatically during those years, including plastics, flame retardants, jet fuel, pesticides, viruses and retroviruses, parental age and, yes, the vaccine program.
For example, the HiB vaccine series was introduced in 1988, a fourth vaccine was added to the DTaP series around 1990, and the HepB series was introduced in 1991, with several years of increased uptake after that before it reached its current high levels. These vaccines have not been studied in direct relation to an ASD risk, except for one HepB paper that found an association (see below).
We also know that autism rates are different in different populations. The latest CDC figures available (from the 1998 birth cohort) show an overall U.S. rate of 91-per-10,000 children (1-in-110), and nearly 2 percent of all boys. Among U.S. military families, however, the rate is reportedly 25 percent higher, at 114-per-10,000 (1-in-88) and among Somali immigrants in Minnesota, it could be as high as 357-per-10,000).
Up in Canada, things are different altogether. In Alberta, the reported rate is, at the very most, 52-per-10,000, which is on par with the rest of Canada, except for Montreal, where the reported rate is 25 percent higher, at 65-per-10,000. The only exception is among Aboriginal (Native American) children in Alberta, whose reported rate was a very low 23-per-10,000. The rate among Aboriginal children in other Canadian provinces is also reportedly low.
Inadequate access to health care and diagnosis, a rural lifestyle and/or genetic differences might explain the apparent lower risk, the authors said, noting a somewhat similar trend among Aboriginal children in Australia, "and pointing to apparent differences in risk of ASD among Aboriginal people living in industrialized countries compared to the rest of the population."
Meanwhile, children of immigrant parents in Montreal seem to have a much higher ASD rate than average.
Exposure to environmental factors most likely not only increased between 1988 and 1992, it may have been most impactful among children of Somali immigrants, followed by U.S. children of military personnel, followed by other U.S. children, followed by children of immigrants to Canada, followed by non-Indian Canadian-born children and (possibly) followed by Aboriginal children in Canada.
Of course, these exposures would have to be studied in the context of genetic make-up, which might vary significantly among some of these populations and thus affect their response to environmental triggers. There are probably differences in the way children are diagnosed and documented in different regions, as well, due to cultutral and other factors.
On the other hand, if you look at vaccination rates, you find that Canadian Aboriginal children lag behind other Canadians by about 20 percent, and "suffered from higher rates of vaccine-preventable diseases," as a result, according to Health Canada.
Meanwhile, unlike U.S. children, most Canadian kids do not receive the three-dose Hepatitis B vaccine beginning at birth, except for children of immigrants, who are concentrated in large cities like Montreal. One paper in the Journal of Toxicology and Environmental Health suggested that boys who received the HepB vaccine beginning at birth were three times more likely to develop an ASD than boys who did not.
In the second half of this two-part series, I will look at some of the exciting new autism science that has been developed lately, especially around seizure disorders, mitochondrial dysfunction and the destruction of myelin -- the fatty acid coating that insulates and protects the brain and the rest of the central nervous system.
As I mentioned above, complex seizures, demyelinating disorders and mitochondrial "meltdowns" have all been implicated in autistic regression. All three can happen in nature without vaccines being involved. In fact, all three can be triggered by childhood illnesses that are prevented by vaccines.
In that sense, it's likely that some children have avoided autistic regression precisely because of their immunizations. On the other hand, if vaccines generally prevented ASD, rates would have gone way down since 1988, and not in the opposite direction.
A good example is ADEM, or acute disseminated encephalomyelitis, in which the brain's myelin sheath is severely damaged, usually only temporarily. The U.S. Vaccine Injury Compensation Program (VICP), better known as "Vaccine Court," has ruled that HepB, MMR and other vaccines can result in ADEM and other demyelinating disorders. In one case, Bailey Banks, the VICP found that MMR-induced ADEM resulted in Pervasive Developmental Disorder-Not Otherwise Specified, which is an ASD.
In another successful VICP case, the special master found that the MMR vaccine had contributed to ADEM, as well as GI distress. It was a ruling that eloquently described the paradox of vaccines that can cause the same disorders as the viral infections they were designed to prevent.
"What is striking to the court is that the most common cause of ADEM is the measles virus, and the vaccine at issue is a live (though attenuated) measles virus vaccine," the judge wrote. "That the virus is attenuated in the vaccine does not make it less likely than the natural or wild virus to be the cause of ADEM."
ADEM cases have fallen to one-third of their prior number because of measles vaccination, the ruling noted. But even the government's expert witness defending the MMR "admitted it is biologically plausible that measles vaccine causes ADEM."
Wild measles virus can cause ADEM in 1-in-1,000 children, a very powerful argument for immunization. On the other hand, a small fraction of children might be at risk for ADEM from the MMR vaccine itself, (the special master said the fact that the vaccine measels virus was attenuated made this no less likely, though I am unaware of any MMR-ADEM studies), and that particular vaccine injury might lead to an ASD.
In other cases, such as children with mitochondrial dysfunction, we may want to give some vaccines as early as possible in order to prevent the type of fever that can send these children into autistic regression (hardly the rant of a dangerous anti-vaxer). On the other hand, in one study, 12 out of 17 children with ASD and mitochondrial disease regressed after a fever greater than 101 degrees Fahrenheit. In 4 of those 12 cases (33 percent), the fever occurred after routine vaccination.
The answer in such cases may be to vaccinate earlier, but less intensively. Douglas C. Wallace, Ph.D, head of the Center of Mitochondrial and Epigenomic Medicine at Children's Hospital of Philadelphia, told the National Vaccine Advisory Committee that, when it comes to mitochondrial disorders, "We advocate spreading vaccines out as much as possible. Each time you vaccinate, you're creating a challenge for the system, and if a child has an impaired system, that could in fact trigger further clinical problems."

Finally, we are going to be hearing a good deal more about vaccines, seizure disorders, and autism as a "residual sequela" of the injury. Maybe vaccines can't cause autism, as the government says, but they can cause complex seizures.
And complex seizures, "during early postnatal development may alter synaptic plasticity and contribute to learning and behavioral disorders" in certain types of children, said one recent study. "Early life seizures may produce a variety of cellular and molecular changes in hippocampus that may contribute to the enhanced risk of IDDs and ASDs in patients with early life seizures and epilepsy."
That study did not link vaccine-induced complex seizures to residual sequelae. But the federal Vaccine Injury Compensation Program has many cases of normally developing children who developed seizure disorders and "encephalopathy" (brain disease) following vaccination.
"This pattern is seen frequently in vaccine cases. An otherwise healthy petitioner receives a vaccination, the vaccine causes a fever, which in turn causes or triggers a complex febrile seizure," one VICP special master wrote in ruling that the DTaP vaccine "was the legal cause of (the child's) seizure disorder and developmental delay."
Some children who suffer from vaccine-induced complex seizures go on to suffer from "developmental delay," "behavioral problems," "affective disorders," "mild mental retardation" and other residual sequelae, VICP records show. Some of them also develop an ASD, and some now get government funds to pay for things such as applied behavioral analysis (ABA), a treatment used mostly for ASD.
Either way, the difference between a child with a seizure disorder, encephalopathy, developmental delay and behavioral problems, and a child with autism spectrum disorder, is hardly vast. Given that vaccines can sometimes cause injuries that lead to the former, why is it so outrageous -- why is it so "anti-vaccine" -- to ask if they can lead to the latter?
As one special master wrote: "It is exceedingly reasonable to conclude that where the vaccine is associated with fever and seizure and the seizure is of a complex nature, in the absence of proof of an alternative cause, it is the vaccine that is responsible for a subsequent epilepsy and residual sequelae" (Italics added).
Developmental delays including ASD are residual sequelae of some vaccine-induced adverse events, the VICP has determined. What proportion of ASD cases resulted from a vaccine injury? We may never know.
The CDC estimates that there are about 760,000 Americans under 21 with an ASD. Even if just 1 percent of those cases was linked to vaccines (though I believe it is higher), that would mean 7,600 young Americans with a vaccine-associated ASD.
In that case, their parents would be neither anti-vaccine nor lunatic fringe. They would be right.
This is part one of a two-part series.

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