U.S. News

Health officials cleared of vaccine misconduct

WASHINGTON (Reuters) - Federal health officials did not interfere with key reviews of vaccine safety or cover up an alleged link between a mercury-based vaccine preservative and autism, a congressional report issued on Friday concluded.

The report, the product of an 18-month investigation by the staff of Wyoming Republican Sen. Mike Enzi, was prompted by allegations by activists and experts who think thimerosal, the preservative, can raise the risk of autism in children.

“Our investigation shows that public health officials conducted thorough, science-based studies on autism and vaccines,” Enzi, the top Republican on the Senate Committee on Health, Education, Labor and Pensions, said in a statement.

The report said the U.S. Centers for Disease Control and Prevention did not interfere with reviews of vaccine safety by the Institute of Medicine, which provides advice to U.S. policymakers, and did not cover up alleged findings linking thimerosal to autism.

The investigators said they found shortcomings in the way the institute screened potential members of a panel looking at the issue for conflicts of interest, but said there was no evidence the panel’s work was compromised by this.

An Institute of Medicine report in May 2004 said a thorough review of clinical and epidemiological studies found that neither thimerosal nor the widely used measles-mumps-rubella vaccine were associated with autism.

Enzi said that the investigation does not offer an opinion one way or the other on the safety of thimerosal.


“With up to 1 in 166 children being diagnosed with autism in the United States, it is vital that we improve our understanding of the causes, symptoms, interventions, and supports and services available for individuals with autism spectrum disorder,” Enzi added.

“But for the most part, the allegations brought to the HELP Committee’s attention cannot be confirmed,” Enzi said.

Thimerosal has been used as a preservative in vaccines for decades. The CDC has maintained that thimerosal is safe, but convinced manufacturers to take it out of all childhood vaccines except for flu shots.

Some autism activists have linked cases of autism to vaccines, citing thimerosal as a potential cause of the condition, which can cause symptoms ranging from poor social skills to profound disability and retardation.

The report faulted the U.S. Food and Drug Administration for inappropriately using Environmental Protection Agency mercury guidelines in evaluating the safety of mercury in vaccines. And it found that thimerosal remains in childhood vaccines shipped to developing countries.

“CDC places highest priority on vaccine safety and the integrity and credibility of its vaccine safety research,” CDC spokesman Curtis Allen said by e-mail.

“This report is the result of an exhaustive, careful and independent review of CDC’s actions. We are gratified this report reaffirms CDC’s efforts have been scientifically based and in the best interest of children.”

The activist group SafeMinds, which voices concern about thimerosal and autism, said the investigation left several key questions unanswered, adding, “The report supported our concern that FDA failed in its statutory obligation to demonstrate that mercury used in vaccines was safe.”