In a piece published October 13 on Salon, pediatrician Rahul Parikh takes on Robert Sears, fellow pediatrician and author of The Vaccine Book (2007). Parikh’s piece received a cursory nod from a few science bloggers (hat-tip to Kevin Pho over at MedPage’s KevinMD.com) and generated a flurry of comments (101 as of November 10) over at Salon, but otherwise received little attention. Yet Parikh’s piece is one of the most important articles to show up in the discussion childhood immunizations. Parikh confronts “Dr. Bob” directly in an e-mail exchange, revealing huge gaps in the logic that underlies Sears’ criticism of conventional vaccine schedules — and huge gaps in the scientific literacy of those who believe him.
In The Vaccine Book, Sears taps into the fears mongered by a vocal anti-vaccine community, whose members for years have been trying to prove that vaccines are harmful. The spread of one of the most damaging myths – that vaccines lead to autism – began with a bogus study by Dr. Andrew Wakefield published in The Lancet in 1998. Wakefield’s study was fully retracted in February 2010, after it was revealed that Wakefield had fabricated data. In study after study, in study-of-studies after study-of-studies, no causal effect has been found, yet anti-vaccine proponents continue to hang onto the idea. Without Wakefield’s study to cite, they’re now turning to other purported concerns – for instance, that infants are being overloaded with too much aluminum, or that infant immune systems are overwhelmed by the antigens contained in vaccines.
The medical community’s reaction to Sears’ schedules has been, bluntly, “Hogwash!” But that hasn’t stopped the book from becoming extremely popular among parents. It has sold more than 160,000 copies since its publication in 2007, and more than one pediatrician – Parikh among them – has been faced with vaccine-shy parents holding a copy of the book.
The Sears Schedules: Risky Business
Sears offers two vaccination scenarios for parents, both of which differ radically from the tried-and-tested Centers for Disease Control (CDC) schedule, developed by the Advisory Committee on Immunization Practices (ACIP). Both schedules are problematic and put kids at risk.
“Dr. Bob’s Selective Vaccine Schedule” is designed for parents who want to either skip some vaccines altogether or delay them. Parents who follow this schedule may choose not to immunize their children for a host of vaccine-preventable diseases, including measles, mumps, rubella, varicella, hepatitis A, polio, influenza, and a booster dose to protect against pertussis (“whooping cough”).
“Dr. Bob’s Alternative Vaccine Schedule” is designed for parents who worry that their children are getting too many vaccines at too early an age. Children are never given more than two vaccines at any one doctor’s visit – playing into the myth of the overloaded immune system. Parents who follow this schedule will be making a lot of visits to the doctor’s office: nearly once a month for the first year, once every six months until age four, then at ages 5 and 6. This schedule extends childhood vaccines over 21 visits, instead of the the 13 called for by the ACIP. The increase in number of office visits alone will likely decrease immunization rates. In addition, children will be susceptible to vaccine-preventable diseases for longer periods of times – often during the times when the disease may prove most damaging or deadly to them.
Flawed Logic
Sears “alternative” and “selective” vaccine schedules seem to provide a middle-ground compromise between vaccine proponents and opponents. His answer? “Parents, you have a choice.” It’s a message that resonates with parents, making them feel as if they’re in control. And he seems to offer a well-thought out, moderate, and expert approach to questions about vaccines. He promises to inform parents.
Sears has a gift — and a gift he chooses to use dangerously. As John Snyder wrote in 2009 in his review of the book on the Science Based Medicine blog: “Dr. Sears is a genius. No, not in an Albert Einstein or Pablo Picasso kind of way. He’s more of an Oprah or a Madonna kind of genius. He’s a genius because he has written a book that capitalizes on the vaccine-fearing, anti-establishment mood of the zeitgeist. The book tells parents what they desperately want to hear, and that has made it an overnight success.”
But as a vaccine expert, Sears falls way short of the mark, and Parikh exposes that lack of expertise. Parikh sums up the the impetus for his project – and his findings – thus:
I initially dismissed the book after reading Offit (and others’) criticism, but I wanted to understand its appeal. And I wanted to hear from the author himself, who agreed to answer questions via email. In his book and his responses, I found a physician who is articulate and persuasive — but whose understanding of vaccines is deeply flawed.
In other words, “America’s most trusted physician” doesn’t know much about science or vaccines? Darn right. The truth of Parikh’s assertion becomes more and more evident as the interview progresses. Parikh pops the bubble for all those parents who have been patting themselves on the back for their critical thinking, proudly making ” informed choices” about delaying or selecting vaccines for their kids, based on Sears’ “expert” advice: “It’s hard to point out just how many times Sears uses the same tactics: soft science, circular logic, reporting rumors and outright falsehoods.”
As Offit and others have pointed out, Sears’ grasp of the scientific method is weak, at best. The most blatant example occurs in Sears’ discussion of research seeking a possible link between vaccines and autism. Sears writes, “Some studies have been published in recent years that have failed to show statistical proof of a relationship between vaccines and autism…. However, by the same token, it is also difficult to prove that there is not a connection.”
That latter statement should make any scientist – or seventh-grader – pause. Epidemiological studies can’t prove that a link does not exist between two things – they can only show that the probability of that link is either high or low. And the parents who buy it… well, it’s time for a review of seventh-grade science. Worst of all, Sears has convinced himself that he’s an expert on vaccines.
Parikh isn’t the first to point out the flaws in Sears’ logic. The Vaccine Book has been deconstructed, analyzed, and refuted by many a true vaccine expert. For instance, noted vaccine developer and expert Paul Offit provides a marvelous, step-by-step refutation of Sears’ argumentshere. As Offit notes, Sears’ argument against vaccines is a “misrepresentation of vaccine science” that “misinforms parents trying to make the right decision for their children” and radically misrepresents vaccine science.
Logic, however, doesn’t deter the scientifically illiterate anti-vaccine community, who simply skewer Offit, often calling him “Dr. Proffit.” And Offit reached a limited audience in the Journal of Pediatrics(which deserves kudos for making it freely available). How many non-physician parents read medical journals? When Parikh’s e-mail interview and critique appeared in Salon last month, it reached a mainstream audience (although shame on Salon for classifying this broad-ranging and thoughtful article only under “Autism.” It’s about so much more – public health, health-care costs, access to health care…). Let’s hope that mainstream audience will take notice.