To provide context to the ongoing outbreak of measles linked to visits to Disneyland and the influence of the anti-vaccination movement, science writer Seth Mnookin revisits the saga of one of the most celebrated anti-vaxxers, starlet Jenny McCarthy.

Mnookin’s reporting on McCarthy comes from his indispensable 2012 book “The Panic Virus,” which examines the myth of a link between the measles-mumps-rubella (MMR) vaccine and autism, its origin in a bogus study by notorious British fraud Andrew Wakefield, and its spread by credulous news and entertainment figures. He posted the chapter on McCarthy on the PLoS blog’s website in 2013, when ABC gave her a fresh new platform by naming her to the cast of the talk show “The View.”

The measles outbreak is now up to 87 cases, of which 50 are linked to Disneyland visits. Of the 42 patients whose vaccination status is known, 37 were unvaccinated or only partially vaccinated. Second-order infections are now turning up--patients who were exposed to infected Disneyland visitors but hadn’t been to the park itself.

The outbreak is raising questions about how best to combat some parents’ doubts about the safety of the MMR vaccine, which has been amply documented by science, and about the role of medical regulators in quashing bad advice from pediatricians. More on that in a moment.


Mnookin’s reporting depicts McCarthy, a former Playboy playmate and MTV star, as an easy mark for charlatans. After dabbling in New Age crystal spirituality, she fell in with an anti-vaccination group once her son was diagnosed with autism. She soon became a ubiquitous spokeswoman for a dizzying variety of autism nostrums--special diets, supplements, detox, chelation, hyperbaric chambers, etc., none of which has been shown to have any scientific validity--and for doubts about the MMR vaccine.

Most disturbingly, Mnookin documents how the news and entertainment industry abetted McCarthy’s dangerous campaign. One of the chief offenders is Oprah Winfrey, who exposed her huge television audience to McCarthy, treating her as an expert on autism because she had “mommy instinct.... She knows what she’s talking about,” Oprah advised her fans. But CNN’s Larry King and Time Inc.'s People Magazine also gave McCarthy star treatment. In our celebrity-obsessed culture in which TV actors are often called to testify before Congress on subjects of concern to their fictional characters, this was powerful stuff.

A footnote: Last year, McCarthy claimed that she had been wrongly painted as “anti-vaccine.” Her claim was promptly debunked.

What’s the best way to fight the spread of media-spread misinformation? Dartmouth political scientist Brendan Nyhan says it’s a mistake to demonize vaccine-doubting parents as “selfish” or “dumb.” (As we’ve done.)


In an exchange with the veteran science and environmental journalist Keith Kloor, Nyhan maintains: “We need to maintain and strengthen the consensus around vaccination, but the most effective way to do so isn’t by polarizing and dividing people. The vast majority of parents who don’t vaccinate are intelligent and well-meaning people who are trying to do what’s best for their children. We need to help them make better choices, not ridicule them.”

Yet Nyhan’s own research suggests that the root of anti-vaccine behavior by parents is an unreasoning conviction bordering on fanaticism. His 2013 study showed that anti-vaccine parents remained unswayed by scientific evidence that vaccines were safe--in fact, it sometimes made them more anti-vaccine.

That implies that the best approach may be to step up peer pressure in favor of vaccination, perhaps by making it socially unacceptable. That could have a real impact in affluent, educated communities--such as Marin and Orange counties--that have had declining vaccination rates. Parents there often think they know better than experts, and their views are reinforced by neighbors and popular but irresponsible local pediatricians. The counter-trend may already be surfacing, as the real consequences of nonvaccination and the real perils of measles become apparent, but vaccination rates are so low in some neighborhoods that it may have a long way to go.

What about regulators? It’s proper to ask whether the Medical Board of California, which licenses physicians in the state, has been properly attentive to the issue of whether physicians advising parents to delay or skip childhood vaccinations are upholding their professional responsibilities. The board did not even post an alert about the measles outbreak on its website until Jan. 22, when I asked board officials why none had been issued.


There are no indications that the board has investigated doctors identified in news reports as puveyors of vaccine skepticism, despite news reports from their practices--though its investigations remain confidential until and unless they result in an action against the doctor’s license. Still, as the state’s leading regulator of physicians, the Medical Board should be in the forefront of the battle against anti-vaccination behavior by its licensees. So far, it isn’t. By its inaction, it has ceded the stage to people like Jenny McCarthy.

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FULL COVERAGE: Measles outbreak tied to Disneyland


STORY SO FAR: What you need to know about the outbreak

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