VACCINES AND AUTISM

VACCINES AND AUTISM

For many years there has been a lot of discussion of the possible causative effects of the childhood vaccines. Much of the focus of past years has been on the issue of thimerosal, a preservative agent used in the vaccines. I think one of the main confusions at this point is the apparent inability of those viewing the argument, from either side, to separate the issues of thimerosal and the 'vaccines' themselves.
For example; recently reviewing the web site, http://fourteenstudies.org/ in the 'quick history' link, it presents 8 quotes, 6 of which specifically address only thimerosal as not being causative; and mockingly concludes with "That's an exhaustive and compelling "who's who" of our medical establishment and they are all saying the same thing in no uncertain terms: vaccines do not cause autism. Why in the world would any doctor, parent, or scientist try to argue otherwise?
My review of the evidence has convinced me that thimerosal is not the issue. And that is strongly supported by the fact that thimerosal in the vaccines was reduced to only trace amounts following a directive in 2001; yet the incidence of autism continued to increase. But, that said, I think it is not conclusive that vaccines are not causative.
So the 'nonscientific' on the manufacturer's side use the elimination of thimerosal to argue 'vaccines' are not the cause; and the nonscientific on the affected side continue to rant about thimerosal. Clear, unbiased thinking does not prevail – at least not in what is 'published'. As one of scientific background, I suggest that it is an argument to be won by presenting the necessary scientifically determined data.
My arguments are based my own literature search to review results of clinical studies to see what the data suggested. In particular, I focused on the issue of thimerosal (a compound containing mercury), which had been used as a preservative in vaccines; and which has been highlighted as a believed cause of autism. In the course of that review, I also came across many studies looking at vaccines in general, and also possible genetic factors. I further pursued the genetic factors issue in discussions with a couple of Ph.D. geneticists.

Regarding thimerosal, with rare exception, the clinical data does not show a correlation between thimerosal and the incidence of autism. My findings were supported further by thorough reviews done by government health agencies in this country as well as two European countries in their efforts to determine the need for further restriction on the use of thimerosal.

I understand the point that the major pharmaceutical companies could find ways to suppress data, or studies, that could be damaging to them from the standpoint of legal liability. While I accept that could happen in some cases, I find it unlikely that it could change the overall body of evidence, including the reviews by the FDA. But perhaps that argument need not be pursued in light of history - and the removal of anything more than trace amounts of thimerosal in vaccines in recent years.

Back in the 90's (don't recall the date, but believe in about 1992) the FDA reviewed the issue, and set limits on the use of thimerosal at levels believed to be "safe". In subsequent years there was considerable controversy over what was safe, and there was considerable pressure brought to eliminate thimerosal in childhood vaccines because of the belief that it could cause autism. In 1999 and 2000 the Public Health Services (including the FDA, NIH, CDC, HRSA) issued two Joint Statements, urging vaccine manufacturers to reduce, or eliminate, thimerosal in vaccines as soon as possible. As a result, and with pressure from the FDA, the levels used in childhood vaccines was significantly reduced, and in recent years has been only at 'trace' levels.

The important point here is that there is now significant history of essentially zero thimerosal exposure, yet the incidence of childhood autism has increased - not decreased. I think that is strong support for the conclusion that thimerosal was not a significant causative factor in autism. (http://www.fda.gov/CBER/vaccine/thimerosal.htm#act is a good summary)

Are there other possible factors associated with vaccines? Yes there are; one being the combination of live viruses that are the key ingredient of MMR vaccine. But as of now, clinical studies have not shown a correlation between the vaccines and autism. That doesn't mean it doesn't exist; just that there is no proof. There are only 'testimonials' and testimonials do not constitute scientific data. One only need review testimonials about a myriad of false "miracle cures" to be aware of that.

Perhaps with removal of thimerosal from the discussion, the focus on vaccines can provide evidence one way or the other.

Another point is that the focus on vaccines should detract from studies of other potential causative factors

What about genetic factors? As can be found in the literature, and clarified for me directly; there can be shown to be a genetic influence on the occurrence of practically every human malady. Whereas generally not causative, there are very definite genetic influences on susceptibility. Effectiveness of treatment is also affected by genetics; and the age is coming where the treatment of diseases will be tailored to the individual by reference to genetic mapping.

The data clearly shows that siblings are at a much higher risk than those not genetically related. In the case of twins, the risk is roughly 30 times that of the average child. It remains to be shown the degree to which this is attributed to genetic correlations, verus environmental correlations, since siblings are likely to share common environment as well as more common immunological schedules.

There are also studies that show much higher incidence of autism in certain geographical locations that have certain environmental contamination.

The point of all this is that, at this point in time, it is clear that THE cause of autism is not known. It is most quite likely a combination of factors. Research findings indicate there are genetic, environmental (including immunological), and metabolic components that influence the development of the disorder.

I believe it is not prudent to emphasize one causative factor over another, and certainly not to promote an anti-vaccine position which could promote negative consequences beyond what we can realize.