One of the heated debates, of the many, that arise in discussion of autism related matters is whether the rates of autism increase is real, in whole or in part, or whether the rates are increasing solely because of 1994 diagnostic definition changes in the DSM and increased social awareness. The United States Center for Disease Control however, in arguing that thimerosal, the mercury contained in some vaccines, does not cause autism disorders, has taken the clear and unambiguous position that increasing numbers of autism diagnoses reflect a real increase in autism disorders:
"Does thimerosal cause autism?
Research does not show any link between thimerosal in vaccines and autism, a neurodevelopmental disorder. Although thimerosal was taken out of childhood vaccines in 2001, autism rates have gone up, which is the opposite of what would be expected if thimerosal caused autism."
Obviously if the increases in autism diagnoses did not reflect real increases in autism there would be no merit to the CDC position that increased autism rates confirm that thimerosal does not cause autism. The increases in autism diagnoses are real, autism IS rising, the CDC says so.