Did CDC hide proof that MMR causes autism?

An anti-vaccine account tweeted a photo of a small portion of an email between two CDC scientists discussing changing the criteria for inclusion in the study. In her caption, the anti-vaccine activist claims that studies in 1999 and 2002 found links between vaccines and autism or learning disorders, but researchers allegedly manipulated the data to invalidate these findings and protect the vaccine industry rather than public health.

The claims from the tweet rely on a small snippet from a larger email chain from CDC staff. The email chain discusses a study on the potential link between vaccines containing thimerosal and developmental disorders like autism.

They focus on refining data analysis methods, adjusting for variables like gender and birth year, and reviewing the accuracy of diagnoses. Concerns are raised about the reliability of initial findings, which suggest a possible increased risk for some developmental issues. The team emphasizes the need for careful verification and further analysis before making public statements, highlighting the complexities involved in ensuring accurate and reliable research outcomes in vaccine safety studies.

None of this points to proof of collusion within CDC to hide information. Rather, it is a discussion about how to deal with confounding factors that might lead to incorrect conclusions.

Most importantly, we know that vaccines do not cause autism.

And we know a lot now about thimerosal. Thimerosal has been used safely in vaccines, drugs, and contact solutions since the 1930s. Nowadays, most vaccines use thimerosal-free single-use vials, and thimerosal-free flu vaccines are available for those still concerned. The vast, vast majority of studies show that thimerosal does not increase the risk of autism. In addition, thimerosal has not even been used in childhood vaccines since 2001.