An examination of scientific studies worldwide has found no convincing evidence that vaccines cause autism, according to a committee of experts appointed by the Institute of Medicine.
In particular, no link was found between autism and the measles-mumps-rubella vaccine or vaccines that contain a mercury preservative called thimerosal. The committee released its eighth and final report yesterday in Washington. . . .
As for the measles-mumps-rubella vaccine, 14 epidemiological studies have shown no evidence of a link. The committee dismissed two studies that did show a link as flawed. The committee examined a number of possible biological mechanisms to explain how vaccines might cause autism, but said that all were theoretical and that there was not sufficient proof.
Fewer children today receive vaccines that contain mercury, Mr. Blaxill of SafeMinds said, so if the mercury hypothesis holds true, rates of autism should fall in the next couple of years. The number of cases in California, where autistic children are carefully tracked, declined slightly in the last six months, he said, but it is too soon to know if the drop is a trend.
Stay tuned, though the case for a connection is looking pretty weak.