Sunday, October 28, 2007

Talking points v reality

The fact that mercury poisoning presents differently than autism does not prevent fantastic claims that they are one and the same. To make the case, some individuals rely on conspiracy theories, urban legends, and bad science. Here's a typical sample of their talking points, with related reality checks:

Mercury causes mercury poisoning and should not be injected into any form of life.

Dose makes the poison, and just about any substance has a potential for harm. Fluorine is dangerous in some forms, yet safe enough for toothpaste in another. Chlorine is a deadly gas, yet when combined with sodium, another poison, forms common table salt.

Mercury is a naturally occurring element - the average human body contains about 6 millgrams. A typical flu shot contains 25 micrograms. It would take 240 flu shots to deliver the amount of mercury that we carry already. There is no proof that the miniscule amounts of mercury, once contained in scheduled childhood vaccines in the form of thimerosal, is harmful. What's more, there is no credible mechanism by which thimerosal, at such low doses, could cause autism. Since thimerosal was removed from scheduled childhood vaccines in 2002, there has been no noticeable decline in autism diagnoses. These inconvenient truths have yet to be honestly addressed by vaccine conspiracy buffs.

The medical community caused autism, and wants to hide the truth from the rest of us.

Raise your hand if you believe that 700,000 US physicians could successfully conspire to keep the greatest public health fiasco in history from becoming public. Not to mention government health officials from the past six administrations, including Democrats and Republicans whose code of silence prevents them from ratting the other side out for political gain. Talk about preposterous.

The debate could be ended tomorrow if the mercury defenders would agree to study the vaccinated vs. unvaccinated children.

Wrong again. As Prometheus as Photon in the Darkness explains:
If you want to be able to use the data to find possible causes of autism, it works better to match cases of autism with controls who are the same age and sex. This way, you can look at more than one possible association. On the other hand, if you compare a group of unvaccinated children to a group of vaccinated children, all you can find are conditions that are associated with vaccination.

The only way to end the debate is if both sides agree to accept the scientific consensus. One side already does, so in a sense we're half way there.

The Amish don't vaccinate and they don't have autism.

This canard is based solely on a poorly reported story by Dan Olmsted of the Associated Press. He claims to have trudged the length and breadth of Pennsylvania Amish country looking for autistic kids. Olmsted, who lacks the medical training necessary to identify autism, missed the cryptically-named Clinic for Special Children in Lancaster County, whose patients include Amish children with autism.

Autism exploded in the 90’s with the addition of the thimerosal containing Hepatitis B and the HIB and the expansion of RhoGAM to pregnant mothers.

Children have been exposed to less thimerosal since 2002 than they were 20 years ago, yet the number of diagnoses has not declined. What does that tell us about the association between thimerosal and autism?

No comments: