Skip to content

Children's Vaccines Health Center

Did CDC Conspire to Hide Vaccine Risk?

'Simpsonwood Conspiracy' Claims Debunked; Concerns Remain
Font Size
WebMD Health News
Reviewed by Laura J. Martin, MD

Did the CDC conspire with vaccine advocates to hide evidence that children get autism from mercury in vaccines?

The claim was made most forcefully by Robert F. Kennedy Jr. in a 2005 article published in print by Rolling Stone and online by Salon, and in what Kennedy called an "original research paper" on his web site.

It's a terrific story: A cabal of scientists corrupted by pharmaceutical company cash meets secretly at a wooded enclave outside Atlanta called Simpsonwood to hide convincing evidence that autism is caused by a mercury-based vaccine preservative called thimerosal.

Kennedy, after obtaining a verbatim transcript of the conference, reveals the CDC plot. "If, as the evidence suggests, our public health authorities knowingly allowed the pharmaceutical industry to poison an entire generation of American children, their actions arguably constitute one of the biggest scandals in the annals of American medicine," Kennedy concluded.

It's such a good story, it's still frightening parents seeking information on vaccine safety -- even though by January 2011 the article had been withdrawn by both publishers and removed from their web sites.

Salon published five corrections to the story that "went far in undermining Kennedy's expose," according to Salon's editors. Critics of the Kennedy piece, including a devastating critique by Seth Mnookin in The Panic Virus, "further eroded any faith we had in the story," they wrote.

Kennedy's allegations spurred an 18-month investigation by a U.S. Senate committee. That report found allegations of CDC misconduct to be "unsubstantiated," and concluded that there was no cover-up.

So why does Kennedy's story still frighten parents? What really happened? Is mercury in vaccines still a concern? Why does Simpsonwood continue to vex people on all sides of the vaccine debate? 

Early Concerns About Mercury

The FDA Modernization Act of 1997 called for the FDA to assess the risk of all foods and drugs that contained mercury. In late 1998, the FDA asked vaccine manufacturers to detail the use of mercury in vaccines.

A CDC and FDA review quickly found that in the first six months of life, children were getting a cumulative dose of mercury from vaccines that exceeded the EPA's maximum safe exposure level. All of the mercury from vaccines comes from a compound called thimerosal.

1 | 2 | 3 | 4 | 5

Today on WebMD

Baby getting vaccinated
Is there a link? Get the facts.
syringes and graph illustration
Get a customized vaccine schedule.
baby getting a vaccine
Know the benefits and the risk
nurse holding syringe in front of girl
Should your child have it?

What To Know About The HPV Vaccine
24 Kid Illnesses Parents Should Know
Nausea and Vomiting Remedies Slideshow
Managing Immunization Schedules For Kids

Doctor administering vaccine to toddler
gloved hand holding syringe
infant receiving injection

WebMD Special Sections