Perspectives on vaccine safety, exemptions, and autism links

Tuesday's Washington Post included a story about religious and other non-medical exemptions to state vaccine requirements. The article, "Faith lets some kids skip shots," examines the increase in personal belief exemptions by parents to forgo vaccination and its implications on disease rates as seen by the medical community. Interviewed for the story were Paul Offit, Saad Omer, and Barbara Loe Fisher.

This piece appears a few weeks after the cover story of Time magazine titled "The Truth about Vaccines." The story detailed the ongoing worries about alleged links between MMR or other vaccines with increases in autism rates and the response of the medical community to these concerns. Of particular note is the reporter's discussion of research using genetics and genomics to understand individual responses to vaccination. The story included a useful diagram (.pdf) tracing the recent increase in measles cases in the U.S., an increase suspected of being linked to trends in exemptions.

The Time cover story was likely motivated -- at least in part -- by the case of Hannah Poling which received significant attention this spring. In March, CDC acknowledged that vaccines Poling had received had exacerbated an underlying genetic condition related to mitochondria (a cellular component) leading to symptoms resembling those of autism. The case has been viewed by proponents of the vaccine-autism link as a 'smoking gun,' but CDC officials and others have noted that Poling's diagnosis and condition are exceptional and do not speak to a more general connection between vaccines and autism. The case was the subject of a commentary in the New England Journal of Medicine last month by Paul Offit that focused on the confusion surrounding many aspects of the decision.

Finally, returning to exemptions and their consequences, the New York Times' Ethicist column -- an often light-hearted Q&A on ethical dilemmas -- featured this question last weekend:

"My daughter’s play group consists of children ranging in age from infancy to 4 years old. One mother revealed that she does not vaccinate her son. After much frank but cordial discussion and opinions from pediatricians — some thought she endangered our vaccinated kids; others did not — she felt pressured to leave the group. Did the group behave ethically?"

Based on pediatricians' opinions that the unvaccinated child did not pose a significant threat to her vaccinated playmates (a view that is not held by all in the medical community), 'The Ethicist' concludes that the other parents were wrong to exclude the unvaccinated child.

N.Y. Times public editor examines coverage of vaccine-autism link

In today's New York Times, Public Editor Clark Hoyt takes a look at questions surrounding reporters' handling of contested topics (at least by some) in science and medicine, including allegations of the link between vaccines and autism.

As we wrote last month, the New York Times broke the story about the content of the premiere episode of ABC drama "Eli Stone", triggering a flurry of protest by the American Academy of Pediatrics and others. In his stories, Times reporter Edward Wyatt wrote that the issue was all but settled within the scientific and medical communities, with the possible link between vaccines and autism largely rejected. (A Times editorial published after the episode aired offered a similar point-of-view.)

In his piece today, Hoyt writes:

"Wyatt’s article made clear that there is a debate but did not give equal weight to the two sides. The Times has not since 2005, when two reporters investigated every scientific study and thousands of documents from parents convinced of a link between autism and vaccines, and came down pretty clearly on the side of the scientists.

Wyatt said he relied on that report and read extensively about autism when he got the first hint of what the “Eli Stone” episode would say. "The show seems to portray it as, ‘No one knows,’" he said. “My conclusion was that that is not the case."

Proponents of a possible link were not pleased with Wyatt's portrayal of the scientific debate last month and are likely to be similarly displeased with the concurrence of the Times' public editor today.

ABC drama with mercury-autism plot creates controversy

ABC, the same network that brought us 'Fatal Impact' -- the 2006 TV movie presenting a much-criticized dramatization of an avian flu pandemic -- is drawing fire from medical groups regarding the plot of the premiere episode of 'Eli Stone', a legal drama scheduled to debut on January 31.

As this New York Times story first reported last week, the plot of the first episode involves a 'ripped-from-the-headlines' case about a mercury-based vaccine preservative (called 'mercuritol' in the show) alleged to have caused autism in Eli Stone's client. At the end of the show, the jury apparently agrees that a link exists, deciding against the pharmaceutical industry and awarding the plaintiff $5.2 million.

News of the episode's plot has generated a remarkable amount of criticism from the medical community, including campaigns demanding ABC not air the episode. Here's a follow-up by the Times, "ABC Show Will Go On, Over Protests By Doctors." Leading the opposition has been the American Academy of Pediatrics -- here's a press release demanding the episode's cancellation and a letter to ABC from AAP President Renee Jenkins. Here is more coverage from the Associated Press, Reuters, and USA Today.

While all accounts suggest that 'Eli Stone' is a light-hearted series rather than a serious courtroom drama (commercials for the show prominently feature a singing-and-dancing George Michael, the 1980s pop singer who appears in 'visions' of the lead character), the medical community is still concerned that the show's plot will impact parents' decisions regarding vaccination. Today, the Immunization Action Coalition -- among the nation's most prominent advocates of vaccination -- encouraged readers of its e-mail newsletter to contact ABC and request that they cancel the episode.

Recent papers on vaccine-autism history, mandates, vaccine law, and YouTube

There have been an exceptional number of papers published in medical journals over the past several weeks that are worth mentioning...

• "Mercury, Vaccines, And Autism: One Controversy, Three Histories" -- American Journal of Public Health (subscription required for full text; published online ahead-of-print). From Jeffrey Baker, a physician and historian of medicine at Duke, an examination of the multiple histories that have contributed to the nature of current arguments linking vaccines to autism. Baker traces the parallel histories of thimerosal as a vaccine preservative, mercury as a health risk, autism as a diagnosis, and the relatively recent intersection of these stories.

• "Mandating Vaccination: What Counts as a "Mandate" in Public Health and When Should They Be Used?" -- American Journal of Bioethics (subscription required for full text). By Matthew Wynia of the American Medical Association, a commentary on the imprecise usage of the term 'mandate' (with respect to both vaccination and other public health activities) and the implications thereof. A nice introduction to a topic that deserves more attention from scholars.

• "Vaccine Law 101" -- Journal of Law, Medicine, and Ethics (subscription required for full text). Exactly what the title suggests, a high-altitude overview of the many laws, regulations, and types of litigation related to vaccines. A summary of a conference panel session of the same name. Short on insights and argument, but a very useful starting point for those interested in legal aspects of vaccination.

• "YouTube as a Source of Information on Immunization: A Content Analysis" -- JAMA (subscription required for full text). From a research team at the University of Toronto, a review of vaccine-related content posted on YouTube, examining claims made about vaccines and vaccination as well as the general attitude expressed toward vaccines. Slightly more than half of all videos were not expressly positive about vaccination, and those critical of vaccination tended to receive higher ratings from YouTube visitors. Here's a press release about the paper.
  

More evidence against thimerosal-autism link; critics disagree

This paper in the Archives of General Psychiatry, part of the JAMA family of journals, reports that data "do(es) not show any recent decrease in autism in California despite the exclusion of more than trace levels of thimerosal from nearly all childhood vaccines. The DDS data do not support the hypothesis that exposure to thimerosal during childhood is a primary cause of autism."

Seemingly yet another piece of evidence refuting the thimerosal-vaccines-autism hypothesis, the paper led to coverage from ABC News, the Associated Press, the San Francisco Chronicle, and elsewhere.

Advocates of the link between thimerosal and autism were not swayed, as this Baltimore Sun story explains. SafeMinds, perhaps the most prominent organization focusing on mercury-related vaccine risks, published its own analysis of the paper arguing that the imprecision of the data in the study prevented any variable (including thimerosal) from being ruled out as a cause of increasing autism rates.

Study reports no link between thimerosal and neuropsychological outcomes

In what is sure to mark a new round in the debate regarding the impact of thimerosal in vaccines, a paper published in the latest issue of the New England Journal of Medicine reaches the following conclusion:

"Our study does not support a causal association between early exposure to mercury from thimerosal-containing vaccines and immune globulins and deficits in neuropsychological functioning at the age of 7 to 10 years."

The paper by CDC's William Thompson and (many) colleagues -- "Early Thimerosal Exposure and Neuropsychological Outcomes at 7 to 10 Years" -- is available for free at the NEJM website. The study compared children's performance on a battery of neuropsychological tests to their total exposures to thimerosal during vaccination as infants. The paper repeatedly states that autism was not a focus of this study, but there's little doubt that the findings here will find their way into the vaccines and autism debate, even despite efforts from CDC officials at today's teleconference to emphasize this distinction.

Tomorrow, we'll link to some of the media coverage that this news will surely receive -- it was already prominently featured on several of the national evening news broadcasts tonight. For now, here's coverage from the Associated Press, US News & World Report, and Reuters.

The New England Journal also published two related perspectives on thimerosal and vaccines. Paul Offit writes in "Thimerosal and Vaccines -- A Cautionary Tale" (free full text),

"The thimerosal controversy should stand as a cautionary tale of how not to communicate theoretical risks to the public; otherwise, the lesson inherent in the collateral damage caused by its precipitous removal will remain unlearned."

Stephen Sugarman also contributes a piece titled "Cases in Vaccine Court -- Legal Battles over Vaccines and Autism."

Autism advocates and proponents of a link between thimerosal and autism are already raising questions about the researchers, the study and its conclusions (despite the standards required for publication in the world's premier medical journal). For examples, here are statements from Autism Speaks and SafeMinds (which calls the study 'wrong').

More to come...

Federal hearing rekindles thimerosal-autism debate

As has been widely covered in the media, a significant hearing is underway in Washington, DC, this month, as three Special Masters hear claims from a group of 5,000 plaintiffs alleging a link between thimerosal-containing vaccines (prior to the preservative's removal in 1999) and autism. Directly at stake is whether autism should be included among diagnoses for which compensation can be awarded through the federal government's Vaccine Injury Compensation Program. Advocates of vaccination warn that a ruling in favor of the plaintiffs could bankrupt the compensation program, resulting in dire consequences for U.S. vaccination efforts.

The overwhelming consensus among the medical community remains that no link can be found between thimerosal and autism. (Here's the CDC site on mercury and vaccines.) Critics of this view -- many of whom have close links to children or families affected by autism -- respond that these conclusions are based on flawed or inadequate research, or worse, are the product of a medical and vaccination community with unacceptably close ties to the pharmaceutical industry.

Official information along with audio and transcripts of the proceedings can be found here.

An excellent preview of the proceedings appeared in this story by Shankar Vedantam in last Sunday's Washington Post.

Gardiner Harris of the New York Times reported here on the first day of testimony last Monday, as did this AP story. Over at Slate, Arthur Allen previewed the hearing, and the New Scientist reports on it as well. Both focus on the widely criticized research of Dr. Mark Geier -- undoubtedly the most controversial proponent of a thimerosal-autism link.

Sharyl Atkinson of CBS News offered some very provocative opinions in a web column titled, "Autism: Why The Debate Rages." In the Boston Globe, Paul Offit weighed in via an op-ed titled, "At risk: vaccines -- How a legal case could cripple one of modern medicine's greatest achievements". Offit's op-ed generated a number of critical letters which the Globe printed here.

An interesting sidebar to these proceedings is the reported rift among the autism advocacy community regarding the merits of thimerosal-based explanations for the rise in autism rates vs. other potential explanations. Both the New York Times ("Autism debate strains a family and its charity") and ABC News ("Emotions run high over autism's causes") highlighted the disagreement between members of the Wright family, founders of Autism Speaks, perhaps the most prominent and well-connected autism organization. At The Huffington Post, Robert F. Kennedy, Jr., takes issue with these portrayals of Katie Wright, who believes strongly in a thimerosal-autism link.

The hearing in Washington is scheduled to continue for another week and a half; a decision may take a year.

Caplan on autism and vaccines

Our own Art Caplan weighs in on the increasingly hard to discount evidence rejecting a link between thimerosal (once included in vaccines) and the increasing prevalence of autism in children. (The short explanation: autism rates continue to rise years after thimerosal's removal from vaccines, suggesting very strongly -- if not proving -- that other factors are responsible.)

In today's Philadelphia Inquirer, Caplan writes in an op-ed titled "Fact: No link of vaccine, autism":

"This nation's future, its national security, the safety of its health-care institutions, and the safety of its citizens depends upon vaccination. It is way past time that message got heard by parents, teachers, nurses, doctors, hospital administrators, the media and politicians. If there has been a more harmful urban legend circulating in our society than the vaccine-autism link, it is hard to know what it might be. At a time when vaccines may be our last best hope in facing some of the greatest challenges we and our children face, this legend needs to be put to rest. Vaccination, not vaccine-bashing, is what this nation needs."

The continued focus on a vaccine link to autism (at the expense of other research directions) has long been a source of tension among many in the autism advocacy community. Even with this news, however, signs point to critics of U.S. vaccination policy continuing to argue that vaccines are still somehow linked to autism, via as an-yet-unknown alternate mechanism now that thimerosal is no longer a likely candidate. For more on this shift in strategy, see this post by Barbara Loe Fisher.

"Autism controversy eats at credibility of CDC"

Thursday's Atlanta Journal-Constitution (registration required) has a very good story detailing some of the recent developments in the continuing vaccines and autism controversy. As to the validity of such a link, there's no news and still no evidence to support it, according to the American Academy of Pediatrics and the CDC, among many others. But renewed interest and support from members have Congress have redirected attention to the topic, which by itself has an impact on vaccination, as the story explains...

"As the debate and controversy increasingly finds its way into pediatricians' offices, average parents of healthy children are questioning whether vaccines are safe, sometimes even refusing inoculations.

The CDC and other public health officials insist such questions lack a basis in fact or science. Their greatest concern is that the broadening debate holds the potential to put a new generation of children at certain risk of deadly diseases if confidence in the safety of vaccines is lost and they don't receive recommended shots.

'I think it's huge,' said Dr. Julia McMillan, a member of the American Academy of Pediatrics committee that makes vaccine recommendations. 'There's no pediatrician in practice that doesn't confront this on a weekly basis: families who are questioning the need for – and in some cases refusing — vaccines for their children.'"

Yesterday's USA Today featured a full page ad paid for by several autism advocacy groups which cites Robert F. Kennedy's comments on the CDC last month (which we wrote about here) and links to the website www.putchildrenfirst.org. That site, which includes links to numerous CDC documents, memoranda, and e-mails, describes its mission as follows...

"In our efforts to share the truth with other parents, we have been frustrated by the amount of misinformation in the press stating that the connection between mercury and autism has been disproven. This website was constructed to share the truth about what 'proof' actually means.

The National Immunization program (sic) is at risk. The CDC through the choices made, has eroded public trust. Autism is a national emergency and a national shame. We need independent journalists and members of Congress to take action now and put our children first."

In the AJC, the CDC responds... "CDC spokesman Glen Nowak said many of the documents on the site have been in the public domain for years, and are presented out of context and in ways that may 'look quite ominous' – when they're not." Regarding the USA Today advertisement, the CDC released this response, expressing 'disappointment' at how their (and others') efforts were characterized.

Finally, the Vaccine Education Center at the Children's Hospital of Philadelphia recently updated its page on "Thimerosal and Autism."

More on thimerosal...

With a headline sure to amaze those who don't read the full story, the MetroWest Daily News (part of the Boston Herald family) proclaims, "Study links autism, vaccine." If this were even the least bit true, one suspects the MetroWest Daily News wouldn't be the only media outlet covering the story.

Rather, the story here is in reference to a paper published in the Journal of American Physicians and Surgeons titled "Early Downward Trends in Neurodevelopmental Disorders Following Removal of Thimerosal-Containing Vaccines."

The story explains:

"Autism diagnoses have dropped nationwide since mercury was removed from most childhood vaccines, according to a new study that some say lends credence to charges that vaccinations were responsible for a huge increase in autism cases. "

The paper in questions uses state and federal databases that track autism prevalance as well as VAERS, the Vaccine Adverse Event Reporting System. All of these sources have significant data reliability concerns, which, to the newspaper's credit, are noted in the story.

For example, adverse events can be reported to VAERS by anyone and are not verified for accuracy. This paper in Pediatrics (subscription required) -- Goodman, M.J., and Nordin, J. "Vaccine Adverse Event Reporting Source: A Possible Source of Bias in Longitudinal Studies." Feb. 2006; 117: 387-390 -- finds that most thimerosal-related reports to VAERS were directly related to pending litigation. The authors specifically warn researchers attempting to use VAERS data for studies such as the one above about the serious questions regarding its reliability.

RFK Jr.'s latest on thimerosal

Over at The Huffington Post, Robert F. Kennedy Jr. declares that it's "Time for the CDC to Come Clean" about the events leading to the decision in 1999-2000 to remove thimerosal from childhood vaccines. An excerpt:

"But newly released documents show that behind the scenes CDC was quietly discouraging Thimerosal's removal. In a July 1999 letter, vaccine producer SmithKline Beecham tells CDC that it is ready to produce non-Thimerosal DTP (Diptheria/Tetanus/Pertussis) vaccines immediately and has sufficient inventories to supply the entire U.S. market during the remainder of 1999 and the first half of 2000, by which time other vaccine manufacturers would have their Thimerosal-free DTP vaccines on line.

Thimerosal-laden DTP vaccines containing 25 micrograms of mercury apiece were then being administered to American infants at two months, four months and six months -- far exceeding EPA's recommended safe level for mercury. Had CDC accepted SmithKline's offer, it could have immediately reduced the mercury exposures to vaccinated six-month-old children by 40%.

However, in November, CDC mysteriously sent a letter back rejecting SmithKline's offer. Then, on July 14, 2000 CDC published a deceptive press release promising to require that all vaccines be Thimerosal-free as soon as "adequate supplies are available." This was a full 12 months after the agency had denied SmithKline's proposal.

"If CDC were basing its decision on safety alone, it would have taken SmithKline up on its offer. That's a no-brainer," said a federal health official who requested anonymity. "So there were other considerations beside safety that were guiding their decision making."

Among these "other considerations" were CDC's important concerns for the preservation of the vaccine program, a bureaucratic impulse for self-preservation, and protecting the economic interests of its vaccine industry friends."

While the thimerosal/autism stories have generally faded from the media spotlight (except for a few places, such as Imus, etc.), RFK Jr.'s post and many of the comments that follow it illustrate how strong the passions remain among those certain that a link exists and that the government and vaccine industry covered it up for financial gain.

There's little use reviewing here the arguments of both sides in this debate. What all could probably agree on is that the CDC decision to remove thimerosal in 2000 sent a mixed signal, since the evidence then (and now) cited by the medical community continues to show zero evidence of a link to autism. 'If the evidence is so clear, why call for its removal?' is a reasonable question to ask. What seemingly was an attempt to end the controversy by removing a non-essential ingredient has actually had the reverse effect, increasing skepticism and thoughts of conspiracy among those inclined to think in such a way. Years later, the controversy continues to simmer in many, as RFK Jr.'s comments illustrate.