I was privileged to be able to attend a workshop at Cold Spring Harbor labs on Autism last month and I thought I would share some new pieces of information I learned relevant to the autism/vaccine debate.
First, I should say that in all areas of science that I have encountered you will find evidence on both sides, so if you want to show that Autism is caused by vaccines you will cite one side of the literature, but if you want to show that it isn't you will find equal amounts of data on the other side. That being said, one needs to appreciate the person that is doing the study and the methodology. So, just because there is data out there to support both sides doesn't mean that they are equal in quality.
Prior to this meeting, when asked (and I do get asked very frequently) what I think about the autism/vaccine debate, I would always say "there is no evidence that vaccines cause autism, but that for some children, it may be that vaccines either make their disorder worse or initiate a process that they were already at risk for."
But now I have a slightly different perspective. At this meeting Dr. Eric Fombonne spoke about the numerous (and I mean numerous) epidemiological studies that have been done that show that children who have vaccines and those that don't, have the same risk of developing ASD.
Then you say, well what about the mercury preservative, isn't that bad? Well, a couple responses to this, 1. The mercury preservative that has been suggested (Thimerosal) is ethyl mercury, quite different from methyl mercury that is responsible for mercury poisoning. If you say well what's the difference, imagine the difference between ethyl alcohol (that is in alcoholic beverages) and methyl alcohol (that is in antifreeze). Methyl alcohol is toxic and causes blindness in small doses and death in large doses. Thus, the type of mercury in Thimerosal cannot be compared to the effects of methyl mercury. 2. Thimerosal was removed from almost all childhood vaccines in the late 90's and early 2000's, but the number of ASD is certainly not going down.
Then you say, well what about the MMR vaccine and it's relation to autism. And you might even site Andrew Wakefield. If you believe any of that data (which I do not) I urge you to read "Autism's False Profits" by Paul Offit. As it relates to the MMR, I have a few points, 1. don't confuse this with the Thimerosal argument as MMR has never contained Thimerosal, because the MMR is a live virus, so it never had the need for a mercury preservative, in fact the addition of Thimerosal would kill the vaccine and make it useless. The argument (as far as I understand it) for the MMR causing autism goes something like this, that the measles virus is taken up by the gut and somehow gets into the blood and then into the brain. There is no evidence that this happens or theoretical mechanism that could lead to this happening.
So why do people think that vaccines cause autism? This is based on how our brains work. We are always looking for causal relationships. So, if you eat something and then get sick you will assume that it was the food that made you sick. Which may be true, but may just be a coincidence. There are in fact many coincidences that happen all the time and it doesn't mean that one thing caused the other. Children get most of their vaccines around the time that the symptoms of autism are expected to emerge. This is a temporal correlation and cannot be assumed to be causal. Also, because people who are paid big money (and I mean hundreds of thousands or even millions of dollars) say so. Or they are swayed by these people's statements to believe in data that is of extremely poor quality. And now we have come full circle. Though it is true that you will find support for both sides of the vaccine debate, you need to look at the credentials of the people on both sides and realize that fame and number of times these people have been on TV does not make them experts in the field.
A couple extra points that I didn't know previous regarding vaccines that I thought I would pass along...
1. I said in my earlier post that you can ask your pediatrician to space out the vaccines so the child's immune system doesn't have to deal with all of them at once. I was actually corrected by a immunologist who said that actually the immune system can better develop resistance when the shots are all given together. So, actually you are not helping your child by spreading them out.
2. Though the number of shots have increased over the years people born and vaccinated in the 1970's and earlier actually were getting greater amounts of vaccines because they were not as purified as they are now. So our immune system was actually more taxed than the children now.
3. The one child that won the case in court that is often cited. I previously noted that the judge determined that the vaccine aggravated a metabolic disorder that then lead to the ASD, but interestingly, if you talk to doctors who specialize in metabolic disorders none of them recommend that the children not be vaccinated, so even for these children, it seems that the benefits of the vaccine outweigh any potential risk.
4. A website was also brought to my attention, which I do not support, but thought was interesting called jennymccarthybodycount.com where it lists the number of vaccine preventable deaths and illnesses in the U.S.
It is everyone's responsibility to be educated, we just need to make sure that our education is coming from reliable and knowledgeable sources.