2000 Simpsonwood CDC Conference - in The Anti- Vaccination Movement

In The Anti- Vaccination Movement

The June 20, 2005 issue of Rolling Stone contained an article written by Robert F. Kennedy, Jr. entitled "Deadly Immunity". The article, which was also published on Salon.com, focused on the Simpsonwood conference and alleged that government and private industry had colluded to "thwart the Freedom of Information Act" and "withhold" vaccine-safety findings from the public. Kennedy claimed that the Simpsonwood data linked thiomersal in vaccines to the rise in autism, but that the lead researcher later "reworked his data to bury the link between thimerosal and autism." However, Kennedy's article contained numerous significant errors of fact. The article overstated the amount of ethylmercury in vaccines by several orders of magnitude, erroneously claimed that a researcher held a patent on one of the discussed vaccines, and erroneously claimed that the rotavirus vaccine contained thiomersal, among other errors.

Although Salon.com later admitted that these errors "went far in undermining Kennedy’s exposé", at the time they chose not to retract the piece in the interest of transparency. Instead, the magazine corrected Kennedy's article five times due factual errors, ultimately retracting it in January 2011 because the editors felt that criticisms of the article and clear flaws in the science connecting autism and vaccines undermined the value of the article.

By the time the final study results discussed at Simpsonwood were published in 2003, the lead researcher, Thomas Verstraeten, had gone to work for GlaxoSmithKline. Kennedy contended that the delay in publication gave Verstraeten sufficient time to fix the data around the CDC's alleged objective of obscuring a link between thimerosal and autism. Verstraeten denied the allegations, and published an account of the matter in the journal Pediatrics.

In September 2007, the U.S. Senate Committee on Health, Education, Labor and Pensions rejected allegations of impropriety against Verstraeten and the CDC. Addressing the conspiracy alleged by Kennedy and members of the anti-vaccination movement, the Committee found that: "Instead of hiding the data or restricting access to it, CDC distributed it, often to individuals who had never seen it before, and solicited outside opinion regarding how to interpret it. The transcript of these discussions was made available to the public."