Immune to Reason?

Sharon Jaeger and her partners at Central Pediatrics in St. Paul offer a class every month to address the anxieties of expectant parents. Frequently asked questions have included what to expect at the hospital, how to care for an umbilical cord, and what “ferberizing” really means. In recent months, however, another worry has dominated the discussions—and indeed nearly every appointment with the parents of a newborn about to start routine immunizations: “Are vaccines really safe?”

The question confounds Jaeger, who still shudders when recalling the single measles case she encountered when she was a pediatric intern at Yale University and who considers vaccines that prevent childhood diseases among medicine’s greatest accomplishments. For Jaeger and her colleagues, there is no debate. With childhood immunizations, she says, “we pediatricians are actively trying to put ourselves out of business.”

Yet from parents’ point of view, whether to vaccinate or not may seem to be the greatest debate in public health, one they’ve likely heard argued everywhere from parenting blogs and classes to Oprah’s TV show to the pages of celebrity magazines, which have lately pitted two points of view against each other as though they’re competing teams on Dancing with the Stars. On one side, we have Charlie Sheen, Jim Carrey, and Jenny McCarthy, the former Playboy playmate who contends that the so-called MMR vaccine—a three-in-one shot against measles, mumps, and rubella—caused her six-year-old son Evan’s autism. On the other side are Salma Hayek, Kerri Russell, and Jennifer Garner, who have campaigned for shots to wipe out tetanus, pertussis, and influenza, respectively. Joining their ranks is Amanda Peet, representing Every Child By Two, an immunization advocacy campaign. She recently used the word parasite to describe those parents who reject vaccines for their own children while benefiting from the so-called “community immunity” created by the vast majority of families who follow a recommended immunization schedule. Her apology for that unfortunate choice of words was printed in gossip columns everywhere.

Normally, physicians would probably not feel the need to know the public health stances taken by the celebrities appearing in their waiting-room magazines, but these are unusual times. Scientific evidence is increasingly dismissed as mere opinion (see also global warming and evolution), while intuition is conflated with intelligence. In fact, when Oprah asked McCarthy—who concedes she researched autism at the “University of Google”—what to make of the fact that scientists have found no credible evidence that vaccines cause autism, McCarthy replied, “My science is Evan, and he’s at home.” The audience cheered in support.

It’s against this drumbeat of doubt that pediatricians and public health officials now find themselves making the case for immunizations. “We used to be able to point to the science and just rest on our laurels,” Jaeger says, pointing to vaccines’ success in eradicating polio in the Americas, nearly erasing measles, and making chicken pox seem sooo last century. “Unfortunately, that message isn’t working the way it used to.”

When I had my first child in 2002, I was one of those parents waving my hand with questions about vaccines. What worried me most was a 1998 study in The Lancet, a British medical journal, suggesting a link between the measles component of the MMR vaccine and autism. The media frenzy surrounding that report led to a drop in immunization rates across the UK and was soon followed by a movement to remove the mercury-containing preservative thimerosal from vaccines as a precaution (even though the MMR vaccine in question did not contain thimerosal).

When thimerosal was removed from most shots (it is still found in some forms of inactivated influenza vaccine), the autism rate did not decline. What’s more, in 2004 The Lancet’s editors retracted the study’s findings after learning that its lead author, Andrew Wakefield, had allowed lawyers hoping to sue vaccine manufacturers to recruit some of his test subjects. (In other celebrity news, Wakefield, who’s still under investigation by British medical authorities, has opened an autism clinic in Texas, where two of the Dixie Chicks serve on his board.) Meanwhile, no subsequent research has duplicated his findings or found a link between vaccines and autism, the cause of which is still unknown.

In the absence of a reliable explanation, many people have held tight to the notion that vaccines are to blame. Last fall, a survey by the Florida Institute of Technology of 1,000 adults found that one in four believed that “because vaccines may cause autism, it’s safer not to have a child vaccinated at all.” Even parents who understand the research are not entirely reassured. “As each concern is ruled out, they move on to a new concern,” says Jaeger. For instance, parents now ask about the presence of aluminum salts (used in vaccines since the 1920s) or express concern about whether their child’s immune system is ready for multiple shots, raising the “too many, too soon” argument favored by McCarthy and her allies.

“The Internet has a critical role in this,” says Patsy Stinchfield, director of infectious disease immunology and infection prevention at Children’s Hospitals and Clinics of Minnesota, who says many parents are coming to appointments with articles they’ve found online. “The information is at everyone’s fingertips, but, unfortunately, it’s not always accurate.”

Among the most widely respected resources on the topic is immunize.org, a website run by the St. Paul–based nonprofit Immunization Action Coalition and recognized with awards from the Encyclopaedia Britannica, the National Science Teachers Association, and other groups. “We work very hard to make sure our site shows up near the top of any search,” says associate director Diane Peterson, who acknowledges that the IAC’s collection of dry-eyed epidemiological studies and peer-reviewed medical reports may be no match for the more emotional claims found elsewhere on the Internet. After all, the answers you find online often depend on where everyone else is searching.