Pediatrics > Vaccines
Pay and Practice: Kennedy Stirs Thimerosal Debate
by Joyce Frieden, News Editor, MedPage Today July 24, 2014
Robert F. Kennedy Jr. is putting out a book on the dangers of thimerosal in vaccines, raising an issue that many in the medical and scientific communities hoped was long settled.
The book, "Thimerosal: Let the Science Speak: The Evidence Supporting the Immediate Removal of Mercury -- a Known Neurotoxin -- from Vaccines," is scheduled to be available on Aug. 4.
"Over a decade ago, following a sharp rise in developmental disorders such as autism and [attention-deficit hyperactivity disorder], the mercury-containing preservative Thimerosal was widely believed to have been eliminated from vaccine supplies in the United States and abroad," reads a description of the book on the website Amazon. "However, dangerous quantities of Thimerosal continue to be used, posing a significant threat to public health and leading to a crisis of faith in vaccine safety."
The description ends by saying that removing thimerosal "should increase vaccination rates by restoring the trust of concerned parents in the vaccine program -- a program that is so vitally important to public health."
The anti-thimerosal crusade of Kennedy -- the son of the late U.S. Attorney General Robert F. Kennedy and nephew of President John F. Kennedy -- has gotten its share of press coverage. The Washington Post Magazine profiled Kennedy in a story published on July 18, noting that the thimerosal issue "has consumed him for a decade, even as friends and associates have told him repeatedly that it's a lost cause."
The article portrays Kennedy, who is also known as an environmental activist, as someone well-meaning who is using everything he can -- including his political connections -- to get his message out.
The Post article noted that in a meeting with Sen. Bernie Sanders (I-Vermont), Kennedy pointed out that he is in favor of vaccination and is only publishing the book to put pressure on government officials to remove the thimerosal. "'We don't want to publish this book,' Kennedy told [Sanders], holding up a copy of his manuscript. 'We are very pro-vaccine ... Vaccines save lives.'"
After the Post story came out, a rebuttal of sorts appeared in the website Slate, entitled "Don't Feel Sorry for Robert F. Kennedy, Jr." In it, the author writes, "Even if some senators know enough to nod politely, thank him for stopping by, and then ignore him, Kennedy still commands large and rapturous audiences. He is publishing a book about the supposed dangers of thimerosal, which will bring him another burst of publicity and potentially cause even more parents to refuse to vaccinate their children.
"The number of measles cases in the United States tripled last year -- an entirely preventable disease whose resurgence has been made possible in part by Kennedy's tireless efforts. There are a lot of people who deserve your sympathy as they work tirelessly and thanklessly to improve the world. Robert F. Kennedy Jr. is not one of them."
Vaccine advocates were quick to dismiss Kennedy's claim that thimerosal can cause neurodevelopmental problems. "This hypothesis ... about thimerosal was raised 15 years ago and answered 5 years ago -- it's done," Paul Offit, MD, director of the Vaccine Education Center at the University of Pennsylvania in Philadelphia, said in a phone interview.
"It doesn't matter what Bobby Kennedy, Jr. does -- the only thing is what the data show," he continued. "The question is, are the levels [of mercury] contained in vaccines shown to be harmful? And the answer is no. Thimerosal is ethyl mercury, not environmental mercury, and it's excreted from the body far more quickly ... Breast milk contains far higher [mercury] levels than you would ever get from vaccines."
Vaccines are a victim of their own success, Offit noted. "People don't fear [vaccine-preventable] diseases because they don't see them."
He also said he understands why parents push back against vaccination. "We ask parents to get their children vaccines to prevent 14 different diseases; they can get as many as five [shots] at one time. I understand the pushback." But now that there have been more outbreaks of vaccine-preventable diseases, "we're starting to see parents push back [the other way]. You don't hear the anti-vaccine people so much any more."
William Schaffner, MD, professor of preventive medicine and infectious diseases at Vanderbilt University in Nashville, Tenn., told MedPage Today that it's very difficult to change the minds of "true believers" like Kennedy.
Psychological data show that "if people have very firm beliefs on a subject -- a subject close to their heart in which they have emotional involvement -- when they're presented data contrary to that belief, they double down," said Schaffner, who is also past president of the National Foundation for Infectious Diseases. "They become even more firmly convinced their original concept is correct."
So rather than try to change the minds of "true believers," which isn't going to happen, Schaffner said he's "decided to influence the general population that they're trying to influence -- the parents. I try to be science-based, I try to be coherent, supportive, and empathetic, and I listen very carefully in order to respond to their concerns. It works very well in a general way."
Schaffner said he'd like to see more information about the benefits of vaccines worked into health classes in middle schools and high schools, "because those in a few years are going to become the young parents ... At least, when they encounter a pediatrician or family doctor, [that information will] have a 'booster' effect."
Pay and Practice is a blog for readers with an interest in health policy.